linux/net/core/dev.c

7286 lines
181 KiB

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 17:04:11 +09:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
hlist: drop the node parameter from iterators I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 17:06:00 -08:00
hlist: drop the node parameter from iterators I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 17:06:00 -08:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
hlist: drop the node parameter from iterators I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 17:06:00 -08:00
hlist: drop the node parameter from iterators I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 17:06:00 -08:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
net: fix rtnl notification in atomic context commit 991fb3f74c "dev: always advertise rx_flags changes via netlink" introduced rtnl notification from __dev_set_promiscuity(), which can be called in atomic context. Steps to reproduce: ip tuntap add dev tap1 mode tap ifconfig tap1 up tcpdump -nei tap1 & ip tuntap del dev tap1 mode tap [ 271.627994] device tap1 left promiscuous mode [ 271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940 [ 271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip [ 271.677525] INFO: lockdep is turned off. [ 271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G W 3.12.0-rc3+ #73 [ 271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 271.731254] ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428 [ 271.760261] ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8 [ 271.790683] 0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8 [ 271.822332] Call Trace: [ 271.838234] [<ffffffff817544e5>] dump_stack+0x55/0x76 [ 271.854446] [<ffffffff8108bad1>] __might_sleep+0x181/0x240 [ 271.870836] [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0 [ 271.887076] [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0 [ 271.903368] [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0 [ 271.919716] [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0 [ 271.936088] [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0 [ 271.952504] [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0 [ 271.968902] [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100 [ 271.985302] [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0 [ 272.001642] [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0 [ 272.017917] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.033961] [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50 [ 272.049855] [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0 [ 272.065494] [<ffffffff81732052>] packet_notifier+0x1b2/0x380 [ 272.080915] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.096009] [<ffffffff81761c66>] notifier_call_chain+0x66/0x150 [ 272.110803] [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10 [ 272.125468] [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20 [ 272.139984] [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70 [ 272.154523] [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20 [ 272.168552] [<ffffffff816224c5>] rollback_registered_many+0x145/0x240 [ 272.182263] [<ffffffff81622641>] rollback_registered+0x31/0x40 [ 272.195369] [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90 [ 272.208230] [<ffffffff81547ca0>] __tun_detach+0x140/0x340 [ 272.220686] [<ffffffff81547ed6>] tun_chr_close+0x36/0x60 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:02:42 -07:00
netpoll: protect napi_poll and poll_controller during dev_[open|close] Ivan Vercera was recently backporting commit 9c13cb8bb477a83b9a3c9e5a5478a4e21294a760 to a RHEL kernel, and I noticed that, while this patch protects the tg3 driver from having its ndo_poll_controller routine called during device initalization, it does nothing for the driver during shutdown. I.e. it would be entirely possible to have the ndo_poll_controller method (or subsequently the ndo_poll) routine called for a driver in the netpoll path on CPU A while in parallel on CPU B, the ndo_close or ndo_open routine could be called. Given that the two latter routines tend to initizlize and free many data structures that the former two rely on, the result can easily be data corruption or various other crashes. Furthermore, it seems that this is potentially a problem with all net drivers that support netpoll, and so this should ideally be fixed in a common path. As Ben H Pointed out to me, we can't preform dev_open/dev_close in atomic context, so I've come up with this solution. We can use a mutex to sleep in open/close paths and just do a mutex_trylock in the napi poll path and abandon the poll attempt if we're locked, as we'll just retry the poll on the next send anyway. I've tested this here by flooding netconsole with messages on a system whos nic driver I modfied to periodically return NETDEV_TX_BUSY, so that the netpoll tx workqueue would be forced to send frames and poll the device. While this was going on I rapidly ifdown/up'ed the interface and watched for any problems. I've not found any. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Ivan Vecera <ivecera@redhat.com> CC: "David S. Miller" <davem@davemloft.net> CC: Ben Hutchings <bhutchings@solarflare.com> CC: Francois Romieu <romieu@fr.zoreil.com> CC: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-05 08:05:43 +00:00
netpoll: protect napi_poll and poll_controller during dev_[open|close] Ivan Vercera was recently backporting commit 9c13cb8bb477a83b9a3c9e5a5478a4e21294a760 to a RHEL kernel, and I noticed that, while this patch protects the tg3 driver from having its ndo_poll_controller routine called during device initalization, it does nothing for the driver during shutdown. I.e. it would be entirely possible to have the ndo_poll_controller method (or subsequently the ndo_poll) routine called for a driver in the netpoll path on CPU A while in parallel on CPU B, the ndo_close or ndo_open routine could be called. Given that the two latter routines tend to initizlize and free many data structures that the former two rely on, the result can easily be data corruption or various other crashes. Furthermore, it seems that this is potentially a problem with all net drivers that support netpoll, and so this should ideally be fixed in a common path. As Ben H Pointed out to me, we can't preform dev_open/dev_close in atomic context, so I've come up with this solution. We can use a mutex to sleep in open/close paths and just do a mutex_trylock in the napi poll path and abandon the poll attempt if we're locked, as we'll just retry the poll on the next send anyway. I've tested this here by flooding netconsole with messages on a system whos nic driver I modfied to periodically return NETDEV_TX_BUSY, so that the netpoll tx workqueue would be forced to send frames and poll the device. While this was going on I rapidly ifdown/up'ed the interface and watched for any problems. I've not found any. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Ivan Vecera <ivecera@redhat.com> CC: "David S. Miller" <davem@davemloft.net> CC: Ben Hutchings <bhutchings@solarflare.com> CC: Francois Romieu <romieu@fr.zoreil.com> CC: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-05 08:05:43 +00:00
netpoll: protect napi_poll and poll_controller during dev_[open|close] Ivan Vercera was recently backporting commit 9c13cb8bb477a83b9a3c9e5a5478a4e21294a760 to a RHEL kernel, and I noticed that, while this patch protects the tg3 driver from having its ndo_poll_controller routine called during device initalization, it does nothing for the driver during shutdown. I.e. it would be entirely possible to have the ndo_poll_controller method (or subsequently the ndo_poll) routine called for a driver in the netpoll path on CPU A while in parallel on CPU B, the ndo_close or ndo_open routine could be called. Given that the two latter routines tend to initizlize and free many data structures that the former two rely on, the result can easily be data corruption or various other crashes. Furthermore, it seems that this is potentially a problem with all net drivers that support netpoll, and so this should ideally be fixed in a common path. As Ben H Pointed out to me, we can't preform dev_open/dev_close in atomic context, so I've come up with this solution. We can use a mutex to sleep in open/close paths and just do a mutex_trylock in the napi poll path and abandon the poll attempt if we're locked, as we'll just retry the poll on the next send anyway. I've tested this here by flooding netconsole with messages on a system whos nic driver I modfied to periodically return NETDEV_TX_BUSY, so that the netpoll tx workqueue would be forced to send frames and poll the device. While this was going on I rapidly ifdown/up'ed the interface and watched for any problems. I've not found any. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Ivan Vecera <ivecera@redhat.com> CC: "David S. Miller" <davem@davemloft.net> CC: Ben Hutchings <bhutchings@solarflare.com> CC: Francois Romieu <romieu@fr.zoreil.com> CC: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-05 08:05:43 +00:00
net: fix rtnl notification in atomic context commit 991fb3f74c "dev: always advertise rx_flags changes via netlink" introduced rtnl notification from __dev_set_promiscuity(), which can be called in atomic context. Steps to reproduce: ip tuntap add dev tap1 mode tap ifconfig tap1 up tcpdump -nei tap1 & ip tuntap del dev tap1 mode tap [ 271.627994] device tap1 left promiscuous mode [ 271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940 [ 271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip [ 271.677525] INFO: lockdep is turned off. [ 271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G W 3.12.0-rc3+ #73 [ 271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 271.731254] ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428 [ 271.760261] ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8 [ 271.790683] 0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8 [ 271.822332] Call Trace: [ 271.838234] [<ffffffff817544e5>] dump_stack+0x55/0x76 [ 271.854446] [<ffffffff8108bad1>] __might_sleep+0x181/0x240 [ 271.870836] [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0 [ 271.887076] [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0 [ 271.903368] [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0 [ 271.919716] [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0 [ 271.936088] [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0 [ 271.952504] [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0 [ 271.968902] [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100 [ 271.985302] [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0 [ 272.001642] [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0 [ 272.017917] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.033961] [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50 [ 272.049855] [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0 [ 272.065494] [<ffffffff81732052>] packet_notifier+0x1b2/0x380 [ 272.080915] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.096009] [<ffffffff81761c66>] notifier_call_chain+0x66/0x150 [ 272.110803] [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10 [ 272.125468] [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20 [ 272.139984] [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70 [ 272.154523] [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20 [ 272.168552] [<ffffffff816224c5>] rollback_registered_many+0x145/0x240 [ 272.182263] [<ffffffff81622641>] rollback_registered+0x31/0x40 [ 272.195369] [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90 [ 272.208230] [<ffffffff81547ca0>] __tun_detach+0x140/0x340 [ 272.220686] [<ffffffff81547ed6>] tun_chr_close+0x36/0x60 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:02:42 -07:00
netpoll: protect napi_poll and poll_controller during dev_[open|close] Ivan Vercera was recently backporting commit 9c13cb8bb477a83b9a3c9e5a5478a4e21294a760 to a RHEL kernel, and I noticed that, while this patch protects the tg3 driver from having its ndo_poll_controller routine called during device initalization, it does nothing for the driver during shutdown. I.e. it would be entirely possible to have the ndo_poll_controller method (or subsequently the ndo_poll) routine called for a driver in the netpoll path on CPU A while in parallel on CPU B, the ndo_close or ndo_open routine could be called. Given that the two latter routines tend to initizlize and free many data structures that the former two rely on, the result can easily be data corruption or various other crashes. Furthermore, it seems that this is potentially a problem with all net drivers that support netpoll, and so this should ideally be fixed in a common path. As Ben H Pointed out to me, we can't preform dev_open/dev_close in atomic context, so I've come up with this solution. We can use a mutex to sleep in open/close paths and just do a mutex_trylock in the napi poll path and abandon the poll attempt if we're locked, as we'll just retry the poll on the next send anyway. I've tested this here by flooding netconsole with messages on a system whos nic driver I modfied to periodically return NETDEV_TX_BUSY, so that the netpoll tx workqueue would be forced to send frames and poll the device. While this was going on I rapidly ifdown/up'ed the interface and watched for any problems. I've not found any. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Ivan Vecera <ivecera@redhat.com> CC: "David S. Miller" <davem@davemloft.net> CC: Ben Hutchings <bhutchings@solarflare.com> CC: Francois Romieu <romieu@fr.zoreil.com> CC: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-05 08:05:43 +00:00
net: fix rtnl notification in atomic context commit 991fb3f74c "dev: always advertise rx_flags changes via netlink" introduced rtnl notification from __dev_set_promiscuity(), which can be called in atomic context. Steps to reproduce: ip tuntap add dev tap1 mode tap ifconfig tap1 up tcpdump -nei tap1 & ip tuntap del dev tap1 mode tap [ 271.627994] device tap1 left promiscuous mode [ 271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940 [ 271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip [ 271.677525] INFO: lockdep is turned off. [ 271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G W 3.12.0-rc3+ #73 [ 271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 271.731254] ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428 [ 271.760261] ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8 [ 271.790683] 0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8 [ 271.822332] Call Trace: [ 271.838234] [<ffffffff817544e5>] dump_stack+0x55/0x76 [ 271.854446] [<ffffffff8108bad1>] __might_sleep+0x181/0x240 [ 271.870836] [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0 [ 271.887076] [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0 [ 271.903368] [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0 [ 271.919716] [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0 [ 271.936088] [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0 [ 271.952504] [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0 [ 271.968902] [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100 [ 271.985302] [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0 [ 272.001642] [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0 [ 272.017917] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.033961] [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50 [ 272.049855] [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0 [ 272.065494] [<ffffffff81732052>] packet_notifier+0x1b2/0x380 [ 272.080915] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.096009] [<ffffffff81761c66>] notifier_call_chain+0x66/0x150 [ 272.110803] [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10 [ 272.125468] [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20 [ 272.139984] [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70 [ 272.154523] [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20 [ 272.168552] [<ffffffff816224c5>] rollback_registered_many+0x145/0x240 [ 272.182263] [<ffffffff81622641>] rollback_registered+0x31/0x40 [ 272.195369] [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90 [ 272.208230] [<ffffffff81547ca0>] __tun_detach+0x140/0x340 [ 272.220686] [<ffffffff81547ed6>] tun_chr_close+0x36/0x60 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:02:42 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
net: dont call jump_label_dec from irq context Igor Maravic reported an error caused by jump_label_dec() being called from IRQ context : BUG: sleeping function called from invalid context at kernel/mutex.c:271 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper 1 lock held by swapper/0: #0: (&n->timer){+.-...}, at: [<ffffffff8107ce90>] call_timer_fn+0x0/0x340 Pid: 0, comm: swapper Not tainted 3.2.0-rc2-net-next-mpls+ #1 Call Trace: <IRQ> [<ffffffff8104f417>] __might_sleep+0x137/0x1f0 [<ffffffff816b9a2f>] mutex_lock_nested+0x2f/0x370 [<ffffffff810a89fd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff8109a37f>] ? local_clock+0x6f/0x80 [<ffffffff810a90a5>] ? lock_release_holdtime.part.22+0x15/0x1a0 [<ffffffff81557929>] ? sock_def_write_space+0x59/0x160 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff810969cd>] atomic_dec_and_mutex_lock+0x5d/0x80 [<ffffffff8112fc1d>] jump_label_dec+0x1d/0x50 [<ffffffff81566525>] net_disable_timestamp+0x15/0x20 [<ffffffff81557a75>] sock_disable_timestamp+0x45/0x50 [<ffffffff81557b00>] __sk_free+0x80/0x200 [<ffffffff815578d0>] ? sk_send_sigurg+0x70/0x70 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff81557cba>] sock_wfree+0x3a/0x70 [<ffffffff8155c2b0>] skb_release_head_state+0x70/0x120 [<ffffffff8155c0b6>] __kfree_skb+0x16/0x30 [<ffffffff8155c119>] kfree_skb+0x49/0x170 [<ffffffff815e936e>] arp_error_report+0x3e/0x90 [<ffffffff81575bd9>] neigh_invalidate+0x89/0xc0 [<ffffffff81578dbe>] neigh_timer_handler+0x9e/0x2a0 [<ffffffff81578d20>] ? neigh_update+0x640/0x640 [<ffffffff81073558>] __do_softirq+0xc8/0x3a0 Since jump_label_{inc|dec} must be called from process context only, we must defer jump_label_dec() if net_disable_timestamp() is called from interrupt context. Reported-by: Igor Maravic <igorm@etf.rs> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28 11:16:50 +00:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
net: dont call jump_label_dec from irq context Igor Maravic reported an error caused by jump_label_dec() being called from IRQ context : BUG: sleeping function called from invalid context at kernel/mutex.c:271 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper 1 lock held by swapper/0: #0: (&n->timer){+.-...}, at: [<ffffffff8107ce90>] call_timer_fn+0x0/0x340 Pid: 0, comm: swapper Not tainted 3.2.0-rc2-net-next-mpls+ #1 Call Trace: <IRQ> [<ffffffff8104f417>] __might_sleep+0x137/0x1f0 [<ffffffff816b9a2f>] mutex_lock_nested+0x2f/0x370 [<ffffffff810a89fd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff8109a37f>] ? local_clock+0x6f/0x80 [<ffffffff810a90a5>] ? lock_release_holdtime.part.22+0x15/0x1a0 [<ffffffff81557929>] ? sock_def_write_space+0x59/0x160 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff810969cd>] atomic_dec_and_mutex_lock+0x5d/0x80 [<ffffffff8112fc1d>] jump_label_dec+0x1d/0x50 [<ffffffff81566525>] net_disable_timestamp+0x15/0x20 [<ffffffff81557a75>] sock_disable_timestamp+0x45/0x50 [<ffffffff81557b00>] __sk_free+0x80/0x200 [<ffffffff815578d0>] ? sk_send_sigurg+0x70/0x70 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff81557cba>] sock_wfree+0x3a/0x70 [<ffffffff8155c2b0>] skb_release_head_state+0x70/0x120 [<ffffffff8155c0b6>] __kfree_skb+0x16/0x30 [<ffffffff8155c119>] kfree_skb+0x49/0x170 [<ffffffff815e936e>] arp_error_report+0x3e/0x90 [<ffffffff81575bd9>] neigh_invalidate+0x89/0xc0 [<ffffffff81578dbe>] neigh_timer_handler+0x9e/0x2a0 [<ffffffff81578d20>] ? neigh_update+0x640/0x640 [<ffffffff81073558>] __do_softirq+0xc8/0x3a0 Since jump_label_{inc|dec} must be called from process context only, we must defer jump_label_dec() if net_disable_timestamp() is called from interrupt context. Reported-by: Igor Maravic <igorm@etf.rs> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28 11:16:50 +00:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
net: dont call jump_label_dec from irq context Igor Maravic reported an error caused by jump_label_dec() being called from IRQ context : BUG: sleeping function called from invalid context at kernel/mutex.c:271 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper 1 lock held by swapper/0: #0: (&n->timer){+.-...}, at: [<ffffffff8107ce90>] call_timer_fn+0x0/0x340 Pid: 0, comm: swapper Not tainted 3.2.0-rc2-net-next-mpls+ #1 Call Trace: <IRQ> [<ffffffff8104f417>] __might_sleep+0x137/0x1f0 [<ffffffff816b9a2f>] mutex_lock_nested+0x2f/0x370 [<ffffffff810a89fd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff8109a37f>] ? local_clock+0x6f/0x80 [<ffffffff810a90a5>] ? lock_release_holdtime.part.22+0x15/0x1a0 [<ffffffff81557929>] ? sock_def_write_space+0x59/0x160 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff810969cd>] atomic_dec_and_mutex_lock+0x5d/0x80 [<ffffffff8112fc1d>] jump_label_dec+0x1d/0x50 [<ffffffff81566525>] net_disable_timestamp+0x15/0x20 [<ffffffff81557a75>] sock_disable_timestamp+0x45/0x50 [<ffffffff81557b00>] __sk_free+0x80/0x200 [<ffffffff815578d0>] ? sk_send_sigurg+0x70/0x70 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff81557cba>] sock_wfree+0x3a/0x70 [<ffffffff8155c2b0>] skb_release_head_state+0x70/0x120 [<ffffffff8155c0b6>] __kfree_skb+0x16/0x30 [<ffffffff8155c119>] kfree_skb+0x49/0x170 [<ffffffff815e936e>] arp_error_report+0x3e/0x90 [<ffffffff81575bd9>] neigh_invalidate+0x89/0xc0 [<ffffffff81578dbe>] neigh_timer_handler+0x9e/0x2a0 [<ffffffff81578d20>] ? neigh_update+0x640/0x640 [<ffffffff81073558>] __do_softirq+0xc8/0x3a0 Since jump_label_{inc|dec} must be called from process context only, we must defer jump_label_dec() if net_disable_timestamp() is called from interrupt context. Reported-by: Igor Maravic <igorm@etf.rs> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28 11:16:50 +00:00
net: dont call jump_label_dec from irq context Igor Maravic reported an error caused by jump_label_dec() being called from IRQ context : BUG: sleeping function called from invalid context at kernel/mutex.c:271 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper 1 lock held by swapper/0: #0: (&n->timer){+.-...}, at: [<ffffffff8107ce90>] call_timer_fn+0x0/0x340 Pid: 0, comm: swapper Not tainted 3.2.0-rc2-net-next-mpls+ #1 Call Trace: <IRQ> [<ffffffff8104f417>] __might_sleep+0x137/0x1f0 [<ffffffff816b9a2f>] mutex_lock_nested+0x2f/0x370 [<ffffffff810a89fd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff8109a37f>] ? local_clock+0x6f/0x80 [<ffffffff810a90a5>] ? lock_release_holdtime.part.22+0x15/0x1a0 [<ffffffff81557929>] ? sock_def_write_space+0x59/0x160 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff810969cd>] atomic_dec_and_mutex_lock+0x5d/0x80 [<ffffffff8112fc1d>] jump_label_dec+0x1d/0x50 [<ffffffff81566525>] net_disable_timestamp+0x15/0x20 [<ffffffff81557a75>] sock_disable_timestamp+0x45/0x50 [<ffffffff81557b00>] __sk_free+0x80/0x200 [<ffffffff815578d0>] ? sk_send_sigurg+0x70/0x70 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff81557cba>] sock_wfree+0x3a/0x70 [<ffffffff8155c2b0>] skb_release_head_state+0x70/0x120 [<ffffffff8155c0b6>] __kfree_skb+0x16/0x30 [<ffffffff8155c119>] kfree_skb+0x49/0x170 [<ffffffff815e936e>] arp_error_report+0x3e/0x90 [<ffffffff81575bd9>] neigh_invalidate+0x89/0xc0 [<ffffffff81578dbe>] neigh_timer_handler+0x9e/0x2a0 [<ffffffff81578d20>] ? neigh_update+0x640/0x640 [<ffffffff81073558>] __do_softirq+0xc8/0x3a0 Since jump_label_{inc|dec} must be called from process context only, we must defer jump_label_dec() if net_disable_timestamp() is called from interrupt context. Reported-by: Igor Maravic <igorm@etf.rs> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28 11:16:50 +00:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
net: dont call jump_label_dec from irq context Igor Maravic reported an error caused by jump_label_dec() being called from IRQ context : BUG: sleeping function called from invalid context at kernel/mutex.c:271 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper 1 lock held by swapper/0: #0: (&n->timer){+.-...}, at: [<ffffffff8107ce90>] call_timer_fn+0x0/0x340 Pid: 0, comm: swapper Not tainted 3.2.0-rc2-net-next-mpls+ #1 Call Trace: <IRQ> [<ffffffff8104f417>] __might_sleep+0x137/0x1f0 [<ffffffff816b9a2f>] mutex_lock_nested+0x2f/0x370 [<ffffffff810a89fd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff8109a37f>] ? local_clock+0x6f/0x80 [<ffffffff810a90a5>] ? lock_release_holdtime.part.22+0x15/0x1a0 [<ffffffff81557929>] ? sock_def_write_space+0x59/0x160 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff810969cd>] atomic_dec_and_mutex_lock+0x5d/0x80 [<ffffffff8112fc1d>] jump_label_dec+0x1d/0x50 [<ffffffff81566525>] net_disable_timestamp+0x15/0x20 [<ffffffff81557a75>] sock_disable_timestamp+0x45/0x50 [<ffffffff81557b00>] __sk_free+0x80/0x200 [<ffffffff815578d0>] ? sk_send_sigurg+0x70/0x70 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff81557cba>] sock_wfree+0x3a/0x70 [<ffffffff8155c2b0>] skb_release_head_state+0x70/0x120 [<ffffffff8155c0b6>] __kfree_skb+0x16/0x30 [<ffffffff8155c119>] kfree_skb+0x49/0x170 [<ffffffff815e936e>] arp_error_report+0x3e/0x90 [<ffffffff81575bd9>] neigh_invalidate+0x89/0xc0 [<ffffffff81578dbe>] neigh_timer_handler+0x9e/0x2a0 [<ffffffff81578d20>] ? neigh_update+0x640/0x640 [<ffffffff81073558>] __do_softirq+0xc8/0x3a0 Since jump_label_{inc|dec} must be called from process context only, we must defer jump_label_dec() if net_disable_timestamp() is called from interrupt context. Reported-by: Igor Maravic <igorm@etf.rs> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28 11:16:50 +00:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
net: dont call jump_label_dec from irq context Igor Maravic reported an error caused by jump_label_dec() being called from IRQ context : BUG: sleeping function called from invalid context at kernel/mutex.c:271 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper 1 lock held by swapper/0: #0: (&n->timer){+.-...}, at: [<ffffffff8107ce90>] call_timer_fn+0x0/0x340 Pid: 0, comm: swapper Not tainted 3.2.0-rc2-net-next-mpls+ #1 Call Trace: <IRQ> [<ffffffff8104f417>] __might_sleep+0x137/0x1f0 [<ffffffff816b9a2f>] mutex_lock_nested+0x2f/0x370 [<ffffffff810a89fd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff8109a37f>] ? local_clock+0x6f/0x80 [<ffffffff810a90a5>] ? lock_release_holdtime.part.22+0x15/0x1a0 [<ffffffff81557929>] ? sock_def_write_space+0x59/0x160 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff810969cd>] atomic_dec_and_mutex_lock+0x5d/0x80 [<ffffffff8112fc1d>] jump_label_dec+0x1d/0x50 [<ffffffff81566525>] net_disable_timestamp+0x15/0x20 [<ffffffff81557a75>] sock_disable_timestamp+0x45/0x50 [<ffffffff81557b00>] __sk_free+0x80/0x200 [<ffffffff815578d0>] ? sk_send_sigurg+0x70/0x70 [<ffffffff815e936e>] ? arp_error_report+0x3e/0x90 [<ffffffff81557cba>] sock_wfree+0x3a/0x70 [<ffffffff8155c2b0>] skb_release_head_state+0x70/0x120 [<ffffffff8155c0b6>] __kfree_skb+0x16/0x30 [<ffffffff8155c119>] kfree_skb+0x49/0x170 [<ffffffff815e936e>] arp_error_report+0x3e/0x90 [<ffffffff81575bd9>] neigh_invalidate+0x89/0xc0 [<ffffffff81578dbe>] neigh_timer_handler+0x9e/0x2a0 [<ffffffff81578d20>] ? neigh_update+0x640/0x640 [<ffffffff81073558>] __do_softirq+0xc8/0x3a0 Since jump_label_{inc|dec} must be called from process context only, we must defer jump_label_dec() if net_disable_timestamp() is called from interrupt context. Reported-by: Igor Maravic <igorm@etf.rs> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28 11:16:50 +00:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
net/core: Handle csum for CHECKSUM_COMPLETE VXLAN forwarding commit 2c26d34bbcc0b3f30385d5587aa232289e2eed8e upstream. When using VXLAN tunnels and a sky2 device, I have experienced checksum failures of the following type: [ 4297.761899] eth0: hw csum failure [...] [ 4297.765223] Call Trace: [ 4297.765224] <IRQ> [<ffffffff8172f026>] dump_stack+0x46/0x58 [ 4297.765235] [<ffffffff8162ba52>] netdev_rx_csum_fault+0x42/0x50 [ 4297.765238] [<ffffffff8161c1a0>] ? skb_push+0x40/0x40 [ 4297.765240] [<ffffffff8162325c>] __skb_checksum_complete+0xbc/0xd0 [ 4297.765243] [<ffffffff8168c602>] tcp_v4_rcv+0x2e2/0x950 [ 4297.765246] [<ffffffff81666ca0>] ? ip_rcv_finish+0x360/0x360 These are reliably reproduced in a network topology of: container:eth0 == host(OVS VXLAN on VLAN) == bond0 == eth0 (sky2) -> switch When VXLAN encapsulated traffic is received from a similarly configured peer, the above warning is generated in the receive processing of the encapsulated packet. Note that the warning is associated with the container eth0. The skbs from sky2 have ip_summed set to CHECKSUM_COMPLETE, and because the packet is an encapsulated Ethernet frame, the checksum generated by the hardware includes the inner protocol and Ethernet headers. The receive code is careful to update the skb->csum, except in __dev_forward_skb, as called by dev_forward_skb. __dev_forward_skb calls eth_type_trans, which in turn calls skb_pull_inline(skb, ETH_HLEN) to skip over the Ethernet header, but does not update skb->csum when doing so. This patch resolves the problem by adding a call to skb_postpull_rcsum to update the skb->csum after the call to eth_type_trans. Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-12-19 15:32:00 -08:00
net: implement mechanism for HW based QOS This patch provides a mechanism for lower layer devices to steer traffic using skb->priority to tx queues. This allows for hardware based QOS schemes to use the default qdisc without incurring the penalties related to global state and the qdisc lock. While reliably receiving skbs on the correct tx ring to avoid head of line blocking resulting from shuffling in the LLD. Finally, all the goodness from txq caching and xps/rps can still be leveraged. Many drivers and hardware exist with the ability to implement QOS schemes in the hardware but currently these drivers tend to rely on firmware to reroute specific traffic, a driver specific select_queue or the queue_mapping action in the qdisc. By using select_queue for this drivers need to be updated for each and every traffic type and we lose the goodness of much of the upstream work. Firmware solutions are inherently inflexible. And finally if admins are expected to build a qdisc and filter rules to steer traffic this requires knowledge of how the hardware is currently configured. The number of tx queues and the queue offsets may change depending on resources. Also this approach incurs all the overhead of a qdisc with filters. With the mechanism in this patch users can set skb priority using expected methods ie setsockopt() or the stack can set the priority directly. Then the skb will be steered to the correct tx queues aligned with hardware QOS traffic classes. In the normal case with single traffic class and all queues in this class everything works as is until the LLD enables multiple tcs. To steer the skb we mask out the lower 4 bits of the priority and allow the hardware to configure upto 15 distinct classes of traffic. This is expected to be sufficient for most applications at any rate it is more then the 8021Q spec designates and is equal to the number of prio bands currently implemented in the default qdisc. This in conjunction with a userspace application such as lldpad can be used to implement 8021Q transmission selection algorithms one of these algorithms being the extended transmission selection algorithm currently being used for DCB. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-17 08:06:04 +00:00
net: implement mechanism for HW based QOS This patch provides a mechanism for lower layer devices to steer traffic using skb->priority to tx queues. This allows for hardware based QOS schemes to use the default qdisc without incurring the penalties related to global state and the qdisc lock. While reliably receiving skbs on the correct tx ring to avoid head of line blocking resulting from shuffling in the LLD. Finally, all the goodness from txq caching and xps/rps can still be leveraged. Many drivers and hardware exist with the ability to implement QOS schemes in the hardware but currently these drivers tend to rely on firmware to reroute specific traffic, a driver specific select_queue or the queue_mapping action in the qdisc. By using select_queue for this drivers need to be updated for each and every traffic type and we lose the goodness of much of the upstream work. Firmware solutions are inherently inflexible. And finally if admins are expected to build a qdisc and filter rules to steer traffic this requires knowledge of how the hardware is currently configured. The number of tx queues and the queue offsets may change depending on resources. Also this approach incurs all the overhead of a qdisc with filters. With the mechanism in this patch users can set skb priority using expected methods ie setsockopt() or the stack can set the priority directly. Then the skb will be steered to the correct tx queues aligned with hardware QOS traffic classes. In the normal case with single traffic class and all queues in this class everything works as is until the LLD enables multiple tcs. To steer the skb we mask out the lower 4 bits of the priority and allow the hardware to configure upto 15 distinct classes of traffic. This is expected to be sufficient for most applications at any rate it is more then the 8021Q spec designates and is equal to the number of prio bands currently implemented in the default qdisc. This in conjunction with a userspace application such as lldpad can be used to implement 8021Q transmission selection algorithms one of these algorithms being the extended transmission selection algorithm currently being used for DCB. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-17 08:06:04 +00:00
net: implement mechanism for HW based QOS This patch provides a mechanism for lower layer devices to steer traffic using skb->priority to tx queues. This allows for hardware based QOS schemes to use the default qdisc without incurring the penalties related to global state and the qdisc lock. While reliably receiving skbs on the correct tx ring to avoid head of line blocking resulting from shuffling in the LLD. Finally, all the goodness from txq caching and xps/rps can still be leveraged. Many drivers and hardware exist with the ability to implement QOS schemes in the hardware but currently these drivers tend to rely on firmware to reroute specific traffic, a driver specific select_queue or the queue_mapping action in the qdisc. By using select_queue for this drivers need to be updated for each and every traffic type and we lose the goodness of much of the upstream work. Firmware solutions are inherently inflexible. And finally if admins are expected to build a qdisc and filter rules to steer traffic this requires knowledge of how the hardware is currently configured. The number of tx queues and the queue offsets may change depending on resources. Also this approach incurs all the overhead of a qdisc with filters. With the mechanism in this patch users can set skb priority using expected methods ie setsockopt() or the stack can set the priority directly. Then the skb will be steered to the correct tx queues aligned with hardware QOS traffic classes. In the normal case with single traffic class and all queues in this class everything works as is until the LLD enables multiple tcs. To steer the skb we mask out the lower 4 bits of the priority and allow the hardware to configure upto 15 distinct classes of traffic. This is expected to be sufficient for most applications at any rate it is more then the 8021Q spec designates and is equal to the number of prio bands currently implemented in the default qdisc. This in conjunction with a userspace application such as lldpad can be used to implement 8021Q transmission selection algorithms one of these algorithms being the extended transmission selection algorithm currently being used for DCB. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-17 08:06:04 +00:00
net: implement mechanism for HW based QOS This patch provides a mechanism for lower layer devices to steer traffic using skb->priority to tx queues. This allows for hardware based QOS schemes to use the default qdisc without incurring the penalties related to global state and the qdisc lock. While reliably receiving skbs on the correct tx ring to avoid head of line blocking resulting from shuffling in the LLD. Finally, all the goodness from txq caching and xps/rps can still be leveraged. Many drivers and hardware exist with the ability to implement QOS schemes in the hardware but currently these drivers tend to rely on firmware to reroute specific traffic, a driver specific select_queue or the queue_mapping action in the qdisc. By using select_queue for this drivers need to be updated for each and every traffic type and we lose the goodness of much of the upstream work. Firmware solutions are inherently inflexible. And finally if admins are expected to build a qdisc and filter rules to steer traffic this requires knowledge of how the hardware is currently configured. The number of tx queues and the queue offsets may change depending on resources. Also this approach incurs all the overhead of a qdisc with filters. With the mechanism in this patch users can set skb priority using expected methods ie setsockopt() or the stack can set the priority directly. Then the skb will be steered to the correct tx queues aligned with hardware QOS traffic classes. In the normal case with single traffic class and all queues in this class everything works as is until the LLD enables multiple tcs. To steer the skb we mask out the lower 4 bits of the priority and allow the hardware to configure upto 15 distinct classes of traffic. This is expected to be sufficient for most applications at any rate it is more then the 8021Q spec designates and is equal to the number of prio bands currently implemented in the default qdisc. This in conjunction with a userspace application such as lldpad can be used to implement 8021Q transmission selection algorithms one of these algorithms being the extended transmission selection algorithm currently being used for DCB. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-17 08:06:04 +00:00
xps: Transmit Packet Steering This patch implements transmit packet steering (XPS) for multiqueue devices. XPS selects a transmit queue during packet transmission based on configuration. This is done by mapping the CPU transmitting the packet to a queue. This is the transmit side analogue to RPS-- where RPS is selecting a CPU based on receive queue, XPS selects a queue based on the CPU (previously there was an XPS patch from Eric Dumazet, but that might more appropriately be called transmit completion steering). Each transmit queue can be associated with a number of CPUs which will use the queue to send packets. This is configured as a CPU mask on a per queue basis in: /sys/class/net/eth<n>/queues/tx-<n>/xps_cpus The mappings are stored per device in an inverted data structure that maps CPUs to queues. In the netdevice structure this is an array of num_possible_cpu structures where each structure holds and array of queue_indexes for queues which that CPU can use. The benefits of XPS are improved locality in the per queue data structures. Also, transmit completions are more likely to be done nearer to the sending thread, so this should promote locality back to the socket on free (e.g. UDP). The benefits of XPS are dependent on cache hierarchy, application load, and other factors. XPS would nominally be configured so that a queue would only be shared by CPUs which are sharing a cache, the degenerative configuration woud be that each CPU has it's own queue. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. bnx2x on 16 core AMD XPS (16 queues, 1 TX queue per CPU) 1234K at 100% CPU No XPS (16 queues) 996K at 100% CPU Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-21 13:17:27 +00:00
xps: Transmit Packet Steering This patch implements transmit packet steering (XPS) for multiqueue devices. XPS selects a transmit queue during packet transmission based on configuration. This is done by mapping the CPU transmitting the packet to a queue. This is the transmit side analogue to RPS-- where RPS is selecting a CPU based on receive queue, XPS selects a queue based on the CPU (previously there was an XPS patch from Eric Dumazet, but that might more appropriately be called transmit completion steering). Each transmit queue can be associated with a number of CPUs which will use the queue to send packets. This is configured as a CPU mask on a per queue basis in: /sys/class/net/eth<n>/queues/tx-<n>/xps_cpus The mappings are stored per device in an inverted data structure that maps CPUs to queues. In the netdevice structure this is an array of num_possible_cpu structures where each structure holds and array of queue_indexes for queues which that CPU can use. The benefits of XPS are improved locality in the per queue data structures. Also, transmit completions are more likely to be done nearer to the sending thread, so this should promote locality back to the socket on free (e.g. UDP). The benefits of XPS are dependent on cache hierarchy, application load, and other factors. XPS would nominally be configured so that a queue would only be shared by CPUs which are sharing a cache, the degenerative configuration woud be that each CPU has it's own queue. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. bnx2x on 16 core AMD XPS (16 queues, 1 TX queue per CPU) 1234K at 100% CPU No XPS (16 queues) 996K at 100% CPU Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-21 13:17:27 +00:00
net: implement mechanism for HW based QOS This patch provides a mechanism for lower layer devices to steer traffic using skb->priority to tx queues. This allows for hardware based QOS schemes to use the default qdisc without incurring the penalties related to global state and the qdisc lock. While reliably receiving skbs on the correct tx ring to avoid head of line blocking resulting from shuffling in the LLD. Finally, all the goodness from txq caching and xps/rps can still be leveraged. Many drivers and hardware exist with the ability to implement QOS schemes in the hardware but currently these drivers tend to rely on firmware to reroute specific traffic, a driver specific select_queue or the queue_mapping action in the qdisc. By using select_queue for this drivers need to be updated for each and every traffic type and we lose the goodness of much of the upstream work. Firmware solutions are inherently inflexible. And finally if admins are expected to build a qdisc and filter rules to steer traffic this requires knowledge of how the hardware is currently configured. The number of tx queues and the queue offsets may change depending on resources. Also this approach incurs all the overhead of a qdisc with filters. With the mechanism in this patch users can set skb priority using expected methods ie setsockopt() or the stack can set the priority directly. Then the skb will be steered to the correct tx queues aligned with hardware QOS traffic classes. In the normal case with single traffic class and all queues in this class everything works as is until the LLD enables multiple tcs. To steer the skb we mask out the lower 4 bits of the priority and allow the hardware to configure upto 15 distinct classes of traffic. This is expected to be sufficient for most applications at any rate it is more then the 8021Q spec designates and is equal to the number of prio bands currently implemented in the default qdisc. This in conjunction with a userspace application such as lldpad can be used to implement 8021Q transmission selection algorithms one of these algorithms being the extended transmission selection algorithm currently being used for DCB. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-17 08:06:04 +00:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
[NET]: Deinline some larger functions from netdevice.h On a allyesconfig'ured kernel: Size Uses Wasted Name and definition ===== ==== ====== ================================================ 95 162 12075 netif_wake_queue include/linux/netdevice.h 129 86 9265 dev_kfree_skb_any include/linux/netdevice.h 127 56 5885 netif_device_attach include/linux/netdevice.h 73 86 4505 dev_kfree_skb_irq include/linux/netdevice.h 46 60 1534 netif_device_detach include/linux/netdevice.h 119 16 1485 __netif_rx_schedule include/linux/netdevice.h 143 5 492 netif_rx_schedule include/linux/netdevice.h 81 7 366 netif_schedule include/linux/netdevice.h netif_wake_queue is big because __netif_schedule is a big inline: static inline void __netif_schedule(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { unsigned long flags; struct softnet_data *sd; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); dev->next_sched = sd->output_queue; sd->output_queue = dev; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } } static inline void netif_wake_queue(struct net_device *dev) { #ifdef CONFIG_NETPOLL_TRAP if (netpoll_trap()) return; #endif if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state)) __netif_schedule(dev); } By de-inlining __netif_schedule we are saving a lot of text at each callsite of netif_wake_queue and netif_schedule. __netif_rx_schedule is also big, and it makes more sense to keep both of them out of line. Patch also deinlines dev_kfree_skb_any. We can deinline dev_kfree_skb_irq instead... oh well. netif_device_attach/detach are not hot paths, we can deinline them too. Signed-off-by: Denis Vlasenko <vda@ilport.com.ua> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-29 15:57:29 -08:00
net: fix wrong mac_len calculation for vlans After 1e785f48d29a ("net: Start with correct mac_len in skb_network_protocol") skb->mac_len is used as a start of the calculation in skb_network_protocol() but that is not always correct. If skb->protocol == 8021Q/AD, usually the vlan header is already inserted in the skb (i.e. vlan reorder hdr == 0). Usually when the packet enters dev_hard_xmit it has mac_len == 0 so we take 2 bytes from the destination mac address (skb->data + VLAN_HLEN) as a type in skb_network_protocol() and return vlan_depth == 4. In the case where TSO is off, then the mac_len is set but it's == 18 (ETH_HLEN + VLAN_HLEN), so skb_network_protocol() returns a type from inside the packet and offset == 22. Also make vlan_depth unsigned as suggested before. As suggested by Eric Dumazet, move the while() loop in the if() so we can avoid additional testing in fast path. Here are few netperf tests + debug printk's to illustrate: cat netperf.tso-on.reorder-on.bugged - Vlan -> device (reorder on, default, this case is okay) MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.3.1 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 7111.54 [ 81.605435] skb->len 65226 skb->gso_size 1448 skb->proto 0x800 skb->mac_len 0 vlan_depth 0 type 0x800 - Vlan -> device (reorder off, bad) cat netperf.tso-on.reorder-off.bugged MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.3.1 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 241.35 [ 204.578332] skb->len 1518 skb->gso_size 0 skb->proto 0x8100 skb->mac_len 0 vlan_depth 4 type 0x5301 0x5301 are the last two bytes of the destination mac. And if we stop TSO, we may get even the following: [ 83.343156] skb->len 2966 skb->gso_size 1448 skb->proto 0x8100 skb->mac_len 18 vlan_depth 22 type 0xb84 Because mac_len already accounts for VLAN_HLEN. After the fix: cat netperf.tso-on.reorder-off.fixed MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.3.1 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.01 5001.46 [ 81.888489] skb->len 65230 skb->gso_size 1448 skb->proto 0x8100 skb->mac_len 0 vlan_depth 18 type 0x800 CC: Vlad Yasevich <vyasevic@redhat.com> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Daniel Borkman <dborkman@redhat.com> CC: David S. Miller <davem@davemloft.net> Fixes:1e785f48d29a ("net: Start with correct mac_len in skb_network_protocol") Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-28 18:03:48 +02:00
net: fix wrong mac_len calculation for vlans After 1e785f48d29a ("net: Start with correct mac_len in skb_network_protocol") skb->mac_len is used as a start of the calculation in skb_network_protocol() but that is not always correct. If skb->protocol == 8021Q/AD, usually the vlan header is already inserted in the skb (i.e. vlan reorder hdr == 0). Usually when the packet enters dev_hard_xmit it has mac_len == 0 so we take 2 bytes from the destination mac address (skb->data + VLAN_HLEN) as a type in skb_network_protocol() and return vlan_depth == 4. In the case where TSO is off, then the mac_len is set but it's == 18 (ETH_HLEN + VLAN_HLEN), so skb_network_protocol() returns a type from inside the packet and offset == 22. Also make vlan_depth unsigned as suggested before. As suggested by Eric Dumazet, move the while() loop in the if() so we can avoid additional testing in fast path. Here are few netperf tests + debug printk's to illustrate: cat netperf.tso-on.reorder-on.bugged - Vlan -> device (reorder on, default, this case is okay) MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.3.1 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 7111.54 [ 81.605435] skb->len 65226 skb->gso_size 1448 skb->proto 0x800 skb->mac_len 0 vlan_depth 0 type 0x800 - Vlan -> device (reorder off, bad) cat netperf.tso-on.reorder-off.bugged MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.3.1 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 241.35 [ 204.578332] skb->len 1518 skb->gso_size 0 skb->proto 0x8100 skb->mac_len 0 vlan_depth 4 type 0x5301 0x5301 are the last two bytes of the destination mac. And if we stop TSO, we may get even the following: [ 83.343156] skb->len 2966 skb->gso_size 1448 skb->proto 0x8100 skb->mac_len 18 vlan_depth 22 type 0xb84 Because mac_len already accounts for VLAN_HLEN. After the fix: cat netperf.tso-on.reorder-off.fixed MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.3.1 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.01 5001.46 [ 81.888489] skb->len 65230 skb->gso_size 1448 skb->proto 0x8100 skb->mac_len 0 vlan_depth 18 type 0x800 CC: Vlad Yasevich <vyasevic@redhat.com> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Daniel Borkman <dborkman@redhat.com> CC: David S. Miller <davem@davemloft.net> Fixes:1e785f48d29a ("net: Start with correct mac_len in skb_network_protocol") Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-28 18:03:48 +02:00
net: do not disable sg for packets requiring no checksum A change in a series of VLAN-related changes appears to have inadvertently disabled the use of the scatter gather feature of network cards for transmission of non-IP ethernet protocols like ATA over Ethernet (AoE). Below is a reference to the commit that introduces a "harmonize_features" function that turns off scatter gather when the NIC does not support hardware checksumming for the ethernet protocol of an sk buff. commit f01a5236bd4b140198fbcc550f085e8361fd73fa Author: Jesse Gross <jesse@nicira.com> Date: Sun Jan 9 06:23:31 2011 +0000 net offloading: Generalize netif_get_vlan_features(). The can_checksum_protocol function is not equipped to consider a protocol that does not require checksumming. Calling it for a protocol that requires no checksum is inappropriate. The patch below has harmonize_features call can_checksum_protocol when the protocol needs a checksum, so that the network layer is not forced to perform unnecessary skb linearization on the transmission of AoE packets. Unnecessary linearization results in decreased performance and increased memory pressure, as reported here: http://www.spinics.net/lists/linux-mm/msg15184.html The problem has probably not been widely experienced yet, because only recently has the kernel.org-distributed aoe driver acquired the ability to use payloads of over a page in size, with the patchset recently included in the mm tree: https://lkml.org/lkml/2012/8/28/140 The coraid.com-distributed aoe driver already could use payloads of greater than a page in size, but its users generally do not use the newest kernels. Signed-off-by: Ed Cashin <ecashin@coraid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-19 15:49:00 +00:00
gso: Update tunnel segmentation to support Tx checksum offload This change makes it so that the GRE and VXLAN tunnels can make use of Tx checksum offload support provided by some drivers via the hw_enc_features. Without this fix enabling GSO means sacrificing Tx checksum offload and this actually leads to a performance regression as shown below: Utilization Send Throughput local GSO 10^6bits/s % S state 6276.51 8.39 enabled 7123.52 8.42 disabled To resolve this it was necessary to address two items. First netif_skb_features needed to be updated so that it would correctly handle the Trans Ether Bridging protocol without impacting the need to check for Q-in-Q tagging. To do this it was necessary to update harmonize_features so that it used skb_network_protocol instead of just using the outer protocol. Second it was necessary to update the GRE and UDP tunnel segmentation offloads so that they would reset the encapsulation bit and inner header offsets after the offload was complete. As a result of this change I have seen the following results on a interface with Tx checksum enabled for encapsulated frames: Utilization Send Throughput local GSO 10^6bits/s % S state 7123.52 8.42 disabled 8321.75 5.43 enabled v2: Instead of replacing refrence to skb->protocol with skb_network_protocol just replace the protocol reference in harmonize_features to allow for double VLAN tag checks. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-10 17:05:06 -07:00
gso: Update tunnel segmentation to support Tx checksum offload This change makes it so that the GRE and VXLAN tunnels can make use of Tx checksum offload support provided by some drivers via the hw_enc_features. Without this fix enabling GSO means sacrificing Tx checksum offload and this actually leads to a performance regression as shown below: Utilization Send Throughput local GSO 10^6bits/s % S state 6276.51 8.39 enabled 7123.52 8.42 disabled To resolve this it was necessary to address two items. First netif_skb_features needed to be updated so that it would correctly handle the Trans Ether Bridging protocol without impacting the need to check for Q-in-Q tagging. To do this it was necessary to update harmonize_features so that it used skb_network_protocol instead of just using the outer protocol. Second it was necessary to update the GRE and UDP tunnel segmentation offloads so that they would reset the encapsulation bit and inner header offsets after the offload was complete. As a result of this change I have seen the following results on a interface with Tx checksum enabled for encapsulated frames: Utilization Send Throughput local GSO 10^6bits/s % S state 7123.52 8.42 disabled 8321.75 5.43 enabled v2: Instead of replacing refrence to skb->protocol with skb_network_protocol just replace the protocol reference in harmonize_features to allow for double VLAN tag checks. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-10 17:05:06 -07:00
net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 16:18:26 +08:00
net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 16:18:26 +08:00
net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 16:18:26 +08:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 16:18:26 +08:00
net: Avoid enqueuing skb for default qdiscs dev_queue_xmit enqueue's a skb and calls qdisc_run which dequeue's the skb and xmits it. In most cases, the skb that is enqueue'd is the same one that is dequeue'd (unless the queue gets stopped or multiple cpu's write to the same queue and ends in a race with qdisc_run). For default qdiscs, we can remove the redundant enqueue/dequeue and simply xmit the skb since the default qdisc is work-conserving. The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the default fast queue. The controversial part of the patch is incrementing qlen when a skb is requeued - this is to avoid checks like the second line below: + } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && >> !q->gso_skb && + !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { Results of a 2 hour testing for multiple netperf sessions (1, 2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are aggregate Mb/s across iterations tested with this version on System-X boxes with Chelsio 10gbps cards: ---------------------------------- Size | ORG BW NEW BW | ---------------------------------- 128K | 156964 159381 | 256K | 158650 162042 | ---------------------------------- Changes from ver1: 1. Move sch_direct_xmit declaration from sch_generic.h to pkt_sched.h 2. Update qdisc basic statistics for direct xmit path. 3. Set qlen to zero in qdisc_reset. 4. Changed some function names to more meaningful ones. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-06 01:44:21 +00:00
[NET]: Add netif_tx_lock Various drivers use xmit_lock internally to synchronise with their transmission routines. They do so without setting xmit_lock_owner. This is fine as long as netpoll is not in use. With netpoll it is possible for deadlocks to occur if xmit_lock_owner isn't set. This is because if a printk occurs while xmit_lock is held and xmit_lock_owner is not set can cause netpoll to attempt to take xmit_lock recursively. While it is possible to resolve this by getting netpoll to use trylock, it is suboptimal because netpoll's sole objective is to maximise the chance of getting the printk out on the wire. So delaying or dropping the message is to be avoided as much as possible. So the only alternative is to always set xmit_lock_owner. The following patch does this by introducing the netif_tx_lock family of functions that take care of setting/unsetting xmit_lock_owner. I renamed xmit_lock to _xmit_lock to indicate that it should not be used directly. I didn't provide irq versions of the netif_tx_lock functions since xmit_lock is meant to be a BH-disabling lock. This is pretty much a straight text substitution except for a small bug fix in winbond. It currently uses netif_stop_queue/spin_unlock_wait to stop transmission. This is unsafe as an IRQ can potentially wake up the queue. So it is safer to use netif_tx_disable. The hamradio bits used spin_lock_irq but it is unnecessary as xmit_lock must never be taken in an IRQ handler. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-09 12:20:56 -07:00
net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 16:18:26 +08:00
net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 16:18:26 +08:00
net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 16:18:26 +08:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
net: add a synchronize_net() in netdev_rx_handler_unregister() commit 35d48903e97819 (bonding: fix rx_handler locking) added a race in bonding driver, reported by Steven Rostedt who did a very good diagnosis : <quoting Steven> I'm currently debugging a crash in an old 3.0-rt kernel that one of our customers is seeing. The bug happens with a stress test that loads and unloads the bonding module in a loop (I don't know all the details as I'm not the one that is directly interacting with the customer). But the bug looks to be something that may still be present and possibly present in mainline too. It will just be much harder to trigger it in mainline. In -rt, interrupts are threads, and can schedule in and out just like any other thread. Note, mainline now supports interrupt threads so this may be easily reproducible in mainline as well. I don't have the ability to tell the customer to try mainline or other kernels, so my hands are somewhat tied to what I can do. But according to a core dump, I tracked down that the eth irq thread crashed in bond_handle_frame() here: slave = bond_slave_get_rcu(skb->dev); bond = slave->bond; <--- BUG the slave returned was NULL and accessing slave->bond caused a NULL pointer dereference. Looking at the code that unregisters the handler: void netdev_rx_handler_unregister(struct net_device *dev) { ASSERT_RTNL(); RCU_INIT_POINTER(dev->rx_handler, NULL); RCU_INIT_POINTER(dev->rx_handler_data, NULL); } Which is basically: dev->rx_handler = NULL; dev->rx_handler_data = NULL; And looking at __netif_receive_skb() we have: rx_handler = rcu_dereference(skb->dev->rx_handler); if (rx_handler) { if (pt_prev) { ret = deliver_skb(skb, pt_prev, orig_dev); pt_prev = NULL; } switch (rx_handler(&skb)) { My question to all of you is, what stops this interrupt from happening while the bonding module is unloading? What happens if the interrupt triggers and we have this: CPU0 CPU1 ---- ---- rx_handler = skb->dev->rx_handler netdev_rx_handler_unregister() { dev->rx_handler = NULL; dev->rx_handler_data = NULL; rx_handler() bond_handle_frame() { slave = skb->dev->rx_handler; bond = slave->bond; <-- NULL pointer dereference!!! What protection am I missing in the bond release handler that would prevent the above from happening? </quoting Steven> We can fix bug this in two ways. First is adding a test in bond_handle_frame() and others to check if rx_handler_data is NULL. A second way is adding a synchronize_net() in netdev_rx_handler_unregister() to make sure that a rcu protected reader has the guarantee to see a non NULL rx_handler_data. The second way is better as it avoids an extra test in fast path. Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Pirko <jpirko@redhat.com> Cc: Paul E. McKenney <paulmck@us.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-29 03:01:22 +00:00
net: add a synchronize_net() in netdev_rx_handler_unregister() commit 35d48903e97819 (bonding: fix rx_handler locking) added a race in bonding driver, reported by Steven Rostedt who did a very good diagnosis : <quoting Steven> I'm currently debugging a crash in an old 3.0-rt kernel that one of our customers is seeing. The bug happens with a stress test that loads and unloads the bonding module in a loop (I don't know all the details as I'm not the one that is directly interacting with the customer). But the bug looks to be something that may still be present and possibly present in mainline too. It will just be much harder to trigger it in mainline. In -rt, interrupts are threads, and can schedule in and out just like any other thread. Note, mainline now supports interrupt threads so this may be easily reproducible in mainline as well. I don't have the ability to tell the customer to try mainline or other kernels, so my hands are somewhat tied to what I can do. But according to a core dump, I tracked down that the eth irq thread crashed in bond_handle_frame() here: slave = bond_slave_get_rcu(skb->dev); bond = slave->bond; <--- BUG the slave returned was NULL and accessing slave->bond caused a NULL pointer dereference. Looking at the code that unregisters the handler: void netdev_rx_handler_unregister(struct net_device *dev) { ASSERT_RTNL(); RCU_INIT_POINTER(dev->rx_handler, NULL); RCU_INIT_POINTER(dev->rx_handler_data, NULL); } Which is basically: dev->rx_handler = NULL; dev->rx_handler_data = NULL; And looking at __netif_receive_skb() we have: rx_handler = rcu_dereference(skb->dev->rx_handler); if (rx_handler) { if (pt_prev) { ret = deliver_skb(skb, pt_prev, orig_dev); pt_prev = NULL; } switch (rx_handler(&skb)) { My question to all of you is, what stops this interrupt from happening while the bonding module is unloading? What happens if the interrupt triggers and we have this: CPU0 CPU1 ---- ---- rx_handler = skb->dev->rx_handler netdev_rx_handler_unregister() { dev->rx_handler = NULL; dev->rx_handler_data = NULL; rx_handler() bond_handle_frame() { slave = skb->dev->rx_handler; bond = slave->bond; <-- NULL pointer dereference!!! What protection am I missing in the bond release handler that would prevent the above from happening? </quoting Steven> We can fix bug this in two ways. First is adding a test in bond_handle_frame() and others to check if rx_handler_data is NULL. A second way is adding a synchronize_net() in netdev_rx_handler_unregister() to make sure that a rcu protected reader has the guarantee to see a non NULL rx_handler_data. The second way is better as it avoids an extra test in fast path. Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Pirko <jpirko@redhat.com> Cc: Paul E. McKenney <paulmck@us.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-29 03:01:22 +00:00
net: Always untag vlan-tagged traffic on input. [ Upstream commit 0d5501c1c828fb97d02af50aa9d2b1a5498b94e4 ] Currently the functionality to untag traffic on input resides as part of the vlan module and is build only when VLAN support is enabled in the kernel. When VLAN is disabled, the function vlan_untag() turns into a stub and doesn't really untag the packets. This seems to create an interesting interaction between VMs supporting checksum offloading and some network drivers. There are some drivers that do not allow the user to change tx-vlan-offload feature of the driver. These drivers also seem to assume that any VLAN-tagged traffic they transmit will have the vlan information in the vlan_tci and not in the vlan header already in the skb. When transmitting skbs that already have tagged data with partial checksum set, the checksum doesn't appear to be updated correctly by the card thus resulting in a failure to establish TCP connections. The following is a packet trace taken on the receiver where a sender is a VM with a VLAN configued. The host VM is running on doest not have VLAN support and the outging interface on the host is tg3: 10:12:43.503055 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q (0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27243, offset 0, flags [DF], proto TCP (6), length 60) 10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect -> 0x48d9), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val 4294837885 ecr 0,nop,wscale 7], length 0 10:12:44.505556 52:54:00:ae:42:3f > 28:d2:44:7d:c2:de, ethertype 802.1Q (0x8100), length 78: vlan 100, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 27244, offset 0, flags [DF], proto TCP (6), length 60) 10.0.100.1.58545 > 10.0.100.10.ircu-2: Flags [S], cksum 0xdc39 (incorrect -> 0x44ee), seq 1069378582, win 29200, options [mss 1460,sackOK,TS val 4294838888 ecr 0,nop,wscale 7], length 0 This connection finally times out. I've only access to the TG3 hardware in this configuration thus have only tested this with TG3 driver. There are a lot of other drivers that do not permit user changes to vlan acceleration features, and I don't know if they all suffere from a similar issue. The patch attempt to fix this another way. It moves the vlan header stipping code out of the vlan module and always builds it into the kernel network core. This way, even if vlan is not supported on a virtualizatoin host, the virtual machines running on top of such host will still work with VLANs enabled. CC: Patrick McHardy <kaber@trash.net> CC: Nithin Nayak Sujir <nsujir@broadcom.com> CC: Michael Chan <mchan@broadcom.com> CC: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-08 14:42:13 -04:00
net: allow vlan traffic to be received under bond The following configuration used to work as I expected. At least we could use the fcoe interfaces to do MPIO and the bond0 iface to do load balancing or failover. ---eth2.228-fcoe | eth2 -----| | |---- bond0 | eth3 -----| | ---eth3.228-fcoe This worked because of a change we added to allow inactive slaves to rx 'exact' matches. This functionality was kept intact with the rx_handler mechanism. However now the vlan interface attached to the active slave never receives traffic because the bonding rx_handler updates the skb->dev and goto's another_round. Previously, the vlan_do_receive() logic was called before the bonding rx_handler. Now by the time vlan_do_receive calls vlan_find_dev() the skb->dev is set to bond0 and it is clear no vlan is attached to this iface. The vlan lookup fails. This patch moves the VLAN check above the rx_handler. A VLAN tagged frame is now routed to the eth2.228-fcoe iface in the above schematic. Untagged frames continue to the bond0 as normal. This case also remains intact, eth2 --> bond0 --> vlan.228 Here the skb is VLAN tagged but the vlan lookup fails on eth2 causing the bonding rx_handler to be called. On the second pass the vlan lookup is on the bond0 iface and completes as expected. Putting a VLAN.228 on both the bond0 and eth2 device will result in eth2.228 receiving the skb. I don't think this is completely unexpected and was the result prior to the rx_handler result. Note, the same setup is also used for other storage traffic that MPIO is used with eg. iSCSI and similar setups can be contrived without storage protocols. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Jesse Gross <jesse@nicira.com> Reviewed-by: Jiri Pirko <jpirko@redhat.com> Tested-by: Hans Schillstrom <hams.schillstrom@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-10 09:16:41 +00:00
net: allow vlan traffic to be received under bond The following configuration used to work as I expected. At least we could use the fcoe interfaces to do MPIO and the bond0 iface to do load balancing or failover. ---eth2.228-fcoe | eth2 -----| | |---- bond0 | eth3 -----| | ---eth3.228-fcoe This worked because of a change we added to allow inactive slaves to rx 'exact' matches. This functionality was kept intact with the rx_handler mechanism. However now the vlan interface attached to the active slave never receives traffic because the bonding rx_handler updates the skb->dev and goto's another_round. Previously, the vlan_do_receive() logic was called before the bonding rx_handler. Now by the time vlan_do_receive calls vlan_find_dev() the skb->dev is set to bond0 and it is clear no vlan is attached to this iface. The vlan lookup fails. This patch moves the VLAN check above the rx_handler. A VLAN tagged frame is now routed to the eth2.228-fcoe iface in the above schematic. Untagged frames continue to the bond0 as normal. This case also remains intact, eth2 --> bond0 --> vlan.228 Here the skb is VLAN tagged but the vlan lookup fails on eth2 causing the bonding rx_handler to be called. On the second pass the vlan lookup is on the bond0 iface and completes as expected. Putting a VLAN.228 on both the bond0 and eth2 device will result in eth2.228 receiving the skb. I don't think this is completely unexpected and was the result prior to the rx_handler result. Note, the same setup is also used for other storage traffic that MPIO is used with eg. iSCSI and similar setups can be contrived without storage protocols. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Jesse Gross <jesse@nicira.com> Reviewed-by: Jiri Pirko <jpirko@redhat.com> Tested-by: Hans Schillstrom <hams.schillstrom@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-10 09:16:41 +00:00
net: allow vlan traffic to be received under bond The following configuration used to work as I expected. At least we could use the fcoe interfaces to do MPIO and the bond0 iface to do load balancing or failover. ---eth2.228-fcoe | eth2 -----| | |---- bond0 | eth3 -----| | ---eth3.228-fcoe This worked because of a change we added to allow inactive slaves to rx 'exact' matches. This functionality was kept intact with the rx_handler mechanism. However now the vlan interface attached to the active slave never receives traffic because the bonding rx_handler updates the skb->dev and goto's another_round. Previously, the vlan_do_receive() logic was called before the bonding rx_handler. Now by the time vlan_do_receive calls vlan_find_dev() the skb->dev is set to bond0 and it is clear no vlan is attached to this iface. The vlan lookup fails. This patch moves the VLAN check above the rx_handler. A VLAN tagged frame is now routed to the eth2.228-fcoe iface in the above schematic. Untagged frames continue to the bond0 as normal. This case also remains intact, eth2 --> bond0 --> vlan.228 Here the skb is VLAN tagged but the vlan lookup fails on eth2 causing the bonding rx_handler to be called. On the second pass the vlan lookup is on the bond0 iface and completes as expected. Putting a VLAN.228 on both the bond0 and eth2 device will result in eth2.228 receiving the skb. I don't think this is completely unexpected and was the result prior to the rx_handler result. Note, the same setup is also used for other storage traffic that MPIO is used with eg. iSCSI and similar setups can be contrived without storage protocols. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Jesse Gross <jesse@nicira.com> Reviewed-by: Jiri Pirko <jpirko@redhat.com> Tested-by: Hans Schillstrom <hams.schillstrom@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-10 09:16:41 +00:00
bonding: allow arp_ip_targets on separate vlans to use arp validation This allows a bond device to specify an arp_ip_target as a host that is not on the same vlan as the base bond device and still use arp validation. A configuration like this, now works: BONDING_OPTS="mode=active-backup arp_interval=1000 arp_ip_target=10.0.100.1 arp_validate=3" 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth1: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master bond0 qlen 1000 link/ether 00:13:21:be:33:e9 brd ff:ff:ff:ff:ff:ff 3: eth0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master bond0 qlen 1000 link/ether 00:13:21:be:33:e9 brd ff:ff:ff:ff:ff:ff 8: bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue link/ether 00:13:21:be:33:e9 brd ff:ff:ff:ff:ff:ff inet6 fe80::213:21ff:febe:33e9/64 scope link valid_lft forever preferred_lft forever 9: bond0.100@bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue link/ether 00:13:21:be:33:e9 brd ff:ff:ff:ff:ff:ff inet 10.0.100.2/24 brd 10.0.100.255 scope global bond0.100 inet6 fe80::213:21ff:febe:33e9/64 scope link valid_lft forever preferred_lft forever Ethernet Channel Bonding Driver: v3.6.0 (September 26, 2009) Bonding Mode: fault-tolerance (active-backup) Primary Slave: None Currently Active Slave: eth1 MII Status: up MII Polling Interval (ms): 0 Up Delay (ms): 0 Down Delay (ms): 0 ARP Polling Interval (ms): 1000 ARP IP target/s (n.n.n.n form): 10.0.100.1 Slave Interface: eth1 MII Status: up Link Failure Count: 1 Permanent HW addr: 00:40:05:30:ff:30 Slave Interface: eth0 MII Status: up Link Failure Count: 0 Permanent HW addr: 00:13:21:be:33:e9 Signed-off-by: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: Jay Vosburgh <fubar@us.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-14 10:48:58 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]() So here's a boot tested patch on top of Jason's series that does all the cleanups I talked about and turns jump labels into a more intuitive to use facility. It should also address the various misconceptions and confusions that surround jump labels. Typical usage scenarios: #include <linux/static_key.h> struct static_key key = STATIC_KEY_INIT_TRUE; if (static_key_false(&key)) do unlikely code else do likely code Or: if (static_key_true(&key)) do likely code else do unlikely code The static key is modified via: static_key_slow_inc(&key); ... static_key_slow_dec(&key); The 'slow' prefix makes it abundantly clear that this is an expensive operation. I've updated all in-kernel code to use this everywhere. Note that I (intentionally) have not pushed through the rename blindly through to the lowest levels: the actual jump-label patching arch facility should be named like that, so we want to decouple jump labels from the static-key facility a bit. On non-jump-label enabled architectures static keys default to likely()/unlikely() branches. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: a.p.zijlstra@chello.nl Cc: mathieu.desnoyers@efficios.com Cc: davem@davemloft.net Cc: ddaney.cavm@gmail.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 08:31:31 +01:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net-gre-gro: Add GRE support to the GRO stack This patch built on top of Commit 299603e8370a93dd5d8e8d800f0dff1ce2c53d36 ("net-gro: Prepare GRO stack for the upcoming tunneling support") to add the support of the standard GRE (RFC1701/RFC2784/RFC2890) to the GRO stack. It also serves as an example for supporting other encapsulation protocols in the GRO stack in the future. The patch supports version 0 and all the flags (key, csum, seq#) but will flush any pkt with the S (seq#) flag. This is because the S flag is not support by GSO, and a GRO pkt may end up in the forwarding path, thus requiring GSO support to break it up correctly. Currently the "packet_offload" structure only contains L3 (ETH_P_IP/ ETH_P_IPV6) GRO offload support so the encapped pkts are limited to IP pkts (i.e., w/o L2 hdr). But support for other protocol type can be easily added, so is the support for GRE variations like NVGRE. The patch also support csum offload. Specifically if the csum flag is on and the h/w is capable of checksumming the payload (CHECKSUM_COMPLETE), the code will take advantage of the csum computed by the h/w when validating the GRE csum. Note that commit 60769a5dcd8755715c7143b4571d5c44f01796f1 "ipv4: gre: add GRO capability" already introduces GRO capability to IPv4 GRE tunnels, using the gro_cells infrastructure. But GRO is done after GRE hdr has been removed (i.e., decapped). The following patch applies GRO when pkts first come in (before hitting the GRE tunnel code). There is some performance advantage for applying GRO as early as possible. Also this approach is transparent to other subsystem like Open vSwitch where GRE decap is handled outside of the IP stack hence making it harder for the gro_cells stuff to apply. On the other hand, some NICs are still not capable of hashing on the inner hdr of a GRE pkt (RSS). In that case the GRO processing of pkts from the same remote host will all happen on the same CPU and the performance may be suboptimal. I'm including some rough preliminary performance numbers below. Note that the performance will be highly dependent on traffic load, mix as usual. Moreover it also depends on NIC offload features hence the following is by no means a comprehesive study. Local testing and tuning will be needed to decide the best setting. All tests spawned 50 copies of netperf TCP_STREAM and ran for 30 secs. (super_netperf 50 -H 192.168.1.18 -l 30) An IP GRE tunnel with only the key flag on (e.g., ip tunnel add gre1 mode gre local 10.246.17.18 remote 10.246.17.17 ttl 255 key 123) is configured. The GRO support for pkts AFTER decap are controlled through the device feature of the GRE device (e.g., ethtool -K gre1 gro on/off). 1.1 ethtool -K gre1 gro off; ethtool -K eth0 gro off thruput: 9.16Gbps CPU utilization: 19% 1.2 ethtool -K gre1 gro on; ethtool -K eth0 gro off thruput: 5.9Gbps CPU utilization: 15% 1.3 ethtool -K gre1 gro off; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 12-13% 1.4 ethtool -K gre1 gro on; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 10% The following tests were performed on a different NIC that is capable of csum offload. I.e., the h/w is capable of computing IP payload csum (CHECKSUM_COMPLETE). 2.1 ethtool -K gre1 gro on (hence will use gro_cells) 2.1.1 ethtool -K eth0 gro off; csum offload disabled thruput: 8.53Gbps CPU utilization: 9% 2.1.2 ethtool -K eth0 gro off; csum offload enabled thruput: 8.97Gbps CPU utilization: 7-8% 2.1.3 ethtool -K eth0 gro on; csum offload disabled thruput: 8.83Gbps CPU utilization: 5-6% 2.1.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.98Gbps CPU utilization: 5% 2.2 ethtool -K gre1 gro off 2.2.1 ethtool -K eth0 gro off; csum offload disabled thruput: 5.93Gbps CPU utilization: 9% 2.2.2 ethtool -K eth0 gro off; csum offload enabled thruput: 5.62Gbps CPU utilization: 8% 2.2.3 ethtool -K eth0 gro on; csum offload disabled thruput: 7.69Gbps CPU utilization: 8% 2.2.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.96Gbps CPU utilization: 5-6% Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07 10:23:19 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net-gre-gro: Add GRE support to the GRO stack This patch built on top of Commit 299603e8370a93dd5d8e8d800f0dff1ce2c53d36 ("net-gro: Prepare GRO stack for the upcoming tunneling support") to add the support of the standard GRE (RFC1701/RFC2784/RFC2890) to the GRO stack. It also serves as an example for supporting other encapsulation protocols in the GRO stack in the future. The patch supports version 0 and all the flags (key, csum, seq#) but will flush any pkt with the S (seq#) flag. This is because the S flag is not support by GSO, and a GRO pkt may end up in the forwarding path, thus requiring GSO support to break it up correctly. Currently the "packet_offload" structure only contains L3 (ETH_P_IP/ ETH_P_IPV6) GRO offload support so the encapped pkts are limited to IP pkts (i.e., w/o L2 hdr). But support for other protocol type can be easily added, so is the support for GRE variations like NVGRE. The patch also support csum offload. Specifically if the csum flag is on and the h/w is capable of checksumming the payload (CHECKSUM_COMPLETE), the code will take advantage of the csum computed by the h/w when validating the GRE csum. Note that commit 60769a5dcd8755715c7143b4571d5c44f01796f1 "ipv4: gre: add GRO capability" already introduces GRO capability to IPv4 GRE tunnels, using the gro_cells infrastructure. But GRO is done after GRE hdr has been removed (i.e., decapped). The following patch applies GRO when pkts first come in (before hitting the GRE tunnel code). There is some performance advantage for applying GRO as early as possible. Also this approach is transparent to other subsystem like Open vSwitch where GRE decap is handled outside of the IP stack hence making it harder for the gro_cells stuff to apply. On the other hand, some NICs are still not capable of hashing on the inner hdr of a GRE pkt (RSS). In that case the GRO processing of pkts from the same remote host will all happen on the same CPU and the performance may be suboptimal. I'm including some rough preliminary performance numbers below. Note that the performance will be highly dependent on traffic load, mix as usual. Moreover it also depends on NIC offload features hence the following is by no means a comprehesive study. Local testing and tuning will be needed to decide the best setting. All tests spawned 50 copies of netperf TCP_STREAM and ran for 30 secs. (super_netperf 50 -H 192.168.1.18 -l 30) An IP GRE tunnel with only the key flag on (e.g., ip tunnel add gre1 mode gre local 10.246.17.18 remote 10.246.17.17 ttl 255 key 123) is configured. The GRO support for pkts AFTER decap are controlled through the device feature of the GRE device (e.g., ethtool -K gre1 gro on/off). 1.1 ethtool -K gre1 gro off; ethtool -K eth0 gro off thruput: 9.16Gbps CPU utilization: 19% 1.2 ethtool -K gre1 gro on; ethtool -K eth0 gro off thruput: 5.9Gbps CPU utilization: 15% 1.3 ethtool -K gre1 gro off; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 12-13% 1.4 ethtool -K gre1 gro on; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 10% The following tests were performed on a different NIC that is capable of csum offload. I.e., the h/w is capable of computing IP payload csum (CHECKSUM_COMPLETE). 2.1 ethtool -K gre1 gro on (hence will use gro_cells) 2.1.1 ethtool -K eth0 gro off; csum offload disabled thruput: 8.53Gbps CPU utilization: 9% 2.1.2 ethtool -K eth0 gro off; csum offload enabled thruput: 8.97Gbps CPU utilization: 7-8% 2.1.3 ethtool -K eth0 gro on; csum offload disabled thruput: 8.83Gbps CPU utilization: 5-6% 2.1.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.98Gbps CPU utilization: 5% 2.2 ethtool -K gre1 gro off 2.2.1 ethtool -K eth0 gro off; csum offload disabled thruput: 5.93Gbps CPU utilization: 9% 2.2.2 ethtool -K eth0 gro off; csum offload enabled thruput: 5.62Gbps CPU utilization: 8% 2.2.3 ethtool -K eth0 gro on; csum offload disabled thruput: 7.69Gbps CPU utilization: 8% 2.2.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.96Gbps CPU utilization: 5-6% Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07 10:23:19 -08:00
net-gre-gro: Add GRE support to the GRO stack This patch built on top of Commit 299603e8370a93dd5d8e8d800f0dff1ce2c53d36 ("net-gro: Prepare GRO stack for the upcoming tunneling support") to add the support of the standard GRE (RFC1701/RFC2784/RFC2890) to the GRO stack. It also serves as an example for supporting other encapsulation protocols in the GRO stack in the future. The patch supports version 0 and all the flags (key, csum, seq#) but will flush any pkt with the S (seq#) flag. This is because the S flag is not support by GSO, and a GRO pkt may end up in the forwarding path, thus requiring GSO support to break it up correctly. Currently the "packet_offload" structure only contains L3 (ETH_P_IP/ ETH_P_IPV6) GRO offload support so the encapped pkts are limited to IP pkts (i.e., w/o L2 hdr). But support for other protocol type can be easily added, so is the support for GRE variations like NVGRE. The patch also support csum offload. Specifically if the csum flag is on and the h/w is capable of checksumming the payload (CHECKSUM_COMPLETE), the code will take advantage of the csum computed by the h/w when validating the GRE csum. Note that commit 60769a5dcd8755715c7143b4571d5c44f01796f1 "ipv4: gre: add GRO capability" already introduces GRO capability to IPv4 GRE tunnels, using the gro_cells infrastructure. But GRO is done after GRE hdr has been removed (i.e., decapped). The following patch applies GRO when pkts first come in (before hitting the GRE tunnel code). There is some performance advantage for applying GRO as early as possible. Also this approach is transparent to other subsystem like Open vSwitch where GRE decap is handled outside of the IP stack hence making it harder for the gro_cells stuff to apply. On the other hand, some NICs are still not capable of hashing on the inner hdr of a GRE pkt (RSS). In that case the GRO processing of pkts from the same remote host will all happen on the same CPU and the performance may be suboptimal. I'm including some rough preliminary performance numbers below. Note that the performance will be highly dependent on traffic load, mix as usual. Moreover it also depends on NIC offload features hence the following is by no means a comprehesive study. Local testing and tuning will be needed to decide the best setting. All tests spawned 50 copies of netperf TCP_STREAM and ran for 30 secs. (super_netperf 50 -H 192.168.1.18 -l 30) An IP GRE tunnel with only the key flag on (e.g., ip tunnel add gre1 mode gre local 10.246.17.18 remote 10.246.17.17 ttl 255 key 123) is configured. The GRO support for pkts AFTER decap are controlled through the device feature of the GRE device (e.g., ethtool -K gre1 gro on/off). 1.1 ethtool -K gre1 gro off; ethtool -K eth0 gro off thruput: 9.16Gbps CPU utilization: 19% 1.2 ethtool -K gre1 gro on; ethtool -K eth0 gro off thruput: 5.9Gbps CPU utilization: 15% 1.3 ethtool -K gre1 gro off; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 12-13% 1.4 ethtool -K gre1 gro on; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 10% The following tests were performed on a different NIC that is capable of csum offload. I.e., the h/w is capable of computing IP payload csum (CHECKSUM_COMPLETE). 2.1 ethtool -K gre1 gro on (hence will use gro_cells) 2.1.1 ethtool -K eth0 gro off; csum offload disabled thruput: 8.53Gbps CPU utilization: 9% 2.1.2 ethtool -K eth0 gro off; csum offload enabled thruput: 8.97Gbps CPU utilization: 7-8% 2.1.3 ethtool -K eth0 gro on; csum offload disabled thruput: 8.83Gbps CPU utilization: 5-6% 2.1.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.98Gbps CPU utilization: 5% 2.2 ethtool -K gre1 gro off 2.2.1 ethtool -K eth0 gro off; csum offload disabled thruput: 5.93Gbps CPU utilization: 9% 2.2.2 ethtool -K eth0 gro off; csum offload enabled thruput: 5.62Gbps CPU utilization: 8% 2.2.3 ethtool -K eth0 gro on; csum offload disabled thruput: 7.69Gbps CPU utilization: 8% 2.2.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.96Gbps CPU utilization: 5-6% Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07 10:23:19 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
vlan: Centralize handling of hardware acceleration. Currently each driver that is capable of vlan hardware acceleration must be aware of the vlan groups that are configured and then pass the stripped tag to a specialized receive function. This is different from other types of hardware offload in that it places a significant amount of knowledge in the driver itself rather keeping it in the networking core. This makes vlan offloading function more similarly to other forms of offloading (such as checksum offloading or TSO) by doing the following: * On receive, stripped vlans are passed directly to the network core, without attempting to check for vlan groups or reconstructing the header if no group * vlans are made less special by folding the logic into the main receive routines * On transmit, the device layer will add the vlan header in software if the hardware doesn't support it, instead of spreading that logic out in upper layers, such as bonding. There are a number of advantages to this: * Fixes all bugs with drivers incorrectly dropping vlan headers at once. * Avoids having to disable VLAN acceleration when in promiscuous mode (good for bridging since it always puts devices in promiscuous mode). * Keeps VLAN tag separate until given to ultimate consumer, which avoids needing to do header reconstruction as in tg3 unless absolutely necessary. * Consolidates common code in core networking. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-20 13:56:06 +00:00
smp: Remove wait argument from __smp_call_function_single() The main point of calling __smp_call_function_single() is to send an IPI in a pure asynchronous way. By embedding a csd in an object, a caller can send the IPI without waiting for a previous one to complete as is required by smp_call_function_single() for example. As such, sending this kind of IPI can be safe even when irqs are disabled. This flexibility comes at the expense of the caller who then needs to synchronize the csd lifecycle by himself and make sure that IPIs on a single csd are serialized. This is how __smp_call_function_single() works when wait = 0 and this usecase is relevant. Now there don't seem to be any usecase with wait = 1 that can't be covered by smp_call_function_single() instead, which is safer. Lets look at the two possible scenario: 1) The user calls __smp_call_function_single(wait = 1) on a csd embedded in an object. It looks like a nice and convenient pattern at the first sight because we can then retrieve the object from the IPI handler easily. But actually it is a waste of memory space in the object since the csd can be allocated from the stack by smp_call_function_single(wait = 1) and the object can be passed an the IPI argument. Besides that, embedding the csd in an object is more error prone because the caller must take care of the serialization of the IPIs for this csd. 2) The user calls __smp_call_function_single(wait = 1) on a csd that is allocated on the stack. It's ok but smp_call_function_single() can do it as well and it already takes care of the allocation on the stack. Again it's more simple and less error prone. Therefore, using the underscore prepend API version with wait = 1 is a bad pattern and a sign that the caller can do safer and more simple. There was a single user of that which has just been converted. So lets remove this option to discourage further users. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@fb.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-02-24 16:40:01 +01:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
[NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-03 16:41:36 -07:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
bonding: Fix stacked device detection in arp monitoring Prior to commit fbd929f2dce460456807a51e18d623db3db9f077 bonding: support QinQ for bond arp interval the arp monitoring code allowed for proper detection of devices stacked on top of vlans. Since the above commit, the code can still detect a device stacked on top of single vlan, but not a device stacked on top of Q-in-Q configuration. The search will only set the inner vlan tag if the route device is the vlan device. However, this is not always the case, as it is possible to extend the stacked configuration. With this patch it is possible to provision devices on top Q-in-Q vlan configuration that should be used as a source of ARP monitoring information. For example: ip link add link bond0 vlan10 type vlan proto 802.1q id 10 ip link add link vlan10 vlan100 type vlan proto 802.1q id 100 ip link add link vlan100 type macvlan Note: This patch limites the number of stacked VLANs to 2, just like before. The original, however had another issue in that if we had more then 2 levels of VLANs, we would end up generating incorrectly tagged traffic. This is no longer possible. Fixes: fbd929f2dce460456807a51e18d623db3db9f077 (bonding: support QinQ for bond arp interval) CC: Jay Vosburgh <j.vosburgh@gmail.com> CC: Veaceslav Falico <vfalico@redhat.com> CC: Andy Gospodarek <andy@greyhouse.net> CC: Ding Tianhong <dingtianhong@huawei.com> CC: Patric McHardy <kaber@trash.net> Signed-off-by: Vlad Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-16 17:20:38 -04:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
net: add lower_dev_list to net_device and make a full mesh This patch adds lower_dev_list list_head to net_device, which is the same as upper_dev_list, only for lower devices, and begins to use it in the same way as the upper list. It also changes the way the whole adjacent device lists work - now they contain *all* of upper/lower devices, not only the first level. The first level devices are distinguished by the bool neighbour field in netdev_adjacent, also added by this patch. There are cases when a device can be added several times to the adjacent list, the simplest would be: /---- eth0.10 ---\ eth0- --- bond0 \---- eth0.20 ---/ where both bond0 and eth0 'see' each other in the adjacent lists two times. To avoid duplication of netdev_adjacent structures ref_nr is being kept as the number of times the device was added to the list. The 'full view' is achieved by adding, on link creation, all of the upper_dev's upper_dev_list devices as upper devices to all of the lower_dev's lower_dev_list devices (and to the lower_dev itself), and vice versa. On unlink they are removed using the same logic. I've tested it with thousands vlans/bonds/bridges, everything works ok and no observable lags even on a huge number of interfaces. Memory footprint for 128 devices interconnected with each other via both upper and lower (which is impossible, but for the comparison) lists would be: 128*128*2*sizeof(netdev_adjacent) = 1.5MB but in the real world we usualy have at most several devices with slaves and a lot of vlans, so the footprint will be much lower. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-28 23:25:05 +02:00
net: core: Always propagate flag changes to interfaces The following commit: b6c40d68ff6498b7f63ddf97cf0aa818d748dee7 net: only invoke dev->change_rx_flags when device is UP tried to fix a problem with VLAN devices and promiscuouse flag setting. The issue was that VLAN device was setting a flag on an interface that was down, thus resulting in bad promiscuity count. This commit blocked flag propagation to any device that is currently down. A later commit: deede2fabe24e00bd7e246eb81cd5767dc6fcfc7 vlan: Don't propagate flag changes on down interfaces fixed VLAN code to only propagate flags when the VLAN interface is up, thus fixing the same issue as above, only localized to VLAN. The problem we have now is that if we have create a complex stack involving multiple software devices like bridges, bonds, and vlans, then it is possible that the flags would not propagate properly to the physical devices. A simple examle of the scenario is the following: eth0----> bond0 ----> bridge0 ---> vlan50 If bond0 or eth0 happen to be down at the time bond0 is added to the bridge, then eth0 will never have promisc mode set which is currently required for operation as part of the bridge. As a result, packets with vlan50 will be dropped by the interface. The only 2 devices that implement the special flag handling are VLAN and DSA and they both have required code to prevent incorrect flag propagation. As a result we can remove the generic solution introduced in b6c40d68ff6498b7f63ddf97cf0aa818d748dee7 and leave it to the individual devices to decide whether they will block flag propagation or not. Reported-by: Stefan Priebe <s.priebe@profihost.ag> Suggested-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: Vlad Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19 20:47:15 -05:00
[NET]: Add net_device change_rx_mode callback Currently the set_multicast_list (and set_rx_mode) callbacks are responsible for configuring the device according to the IFF_PROMISC, IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in case of set_rx_mode). These callbacks can be invoked from BH context without the rtnl_mutex by dev_mc_add/dev_mc_delete, which makes reading the device flags and promiscous/allmulti count racy. For real hardware drivers that just commit all changes to the hardware this is not a real problem since the stack guarantees to call them for every change, so at least the final call will not race and commit the correct configuration to the hardware. For software devices that want to synchronize promiscous and multicast state to an underlying device however this can cause corruption of the underlying device's flags or promisc/allmulti counts. When the software device is concurrently put in promiscous or allmulti mode while set_multicast_list is invoked from bottem half context, the device might synchronize the change to the underlying device without holding the rtnl_mutex, which races with concurrent changes to the underlying device. Add a dev->change_rx_flags hook that is invoked when any of the flags that affect rx filtering change (under the rtnl_mutex), which allows drivers to perform synchronization immediately and only synchronize the address lists in set_multicast_list/set_rx_mode. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 18:51:31 -07:00
[NET]: Add net_device change_rx_mode callback Currently the set_multicast_list (and set_rx_mode) callbacks are responsible for configuring the device according to the IFF_PROMISC, IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in case of set_rx_mode). These callbacks can be invoked from BH context without the rtnl_mutex by dev_mc_add/dev_mc_delete, which makes reading the device flags and promiscous/allmulti count racy. For real hardware drivers that just commit all changes to the hardware this is not a real problem since the stack guarantees to call them for every change, so at least the final call will not race and commit the correct configuration to the hardware. For software devices that want to synchronize promiscous and multicast state to an underlying device however this can cause corruption of the underlying device's flags or promisc/allmulti counts. When the software device is concurrently put in promiscous or allmulti mode while set_multicast_list is invoked from bottem half context, the device might synchronize the change to the underlying device without holding the rtnl_mutex, which races with concurrent changes to the underlying device. Add a dev->change_rx_flags hook that is invoked when any of the flags that affect rx filtering change (under the rtnl_mutex), which allows drivers to perform synchronization immediately and only synchronize the address lists in set_multicast_list/set_rx_mode. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 18:51:31 -07:00
[NET]: Add net_device change_rx_mode callback Currently the set_multicast_list (and set_rx_mode) callbacks are responsible for configuring the device according to the IFF_PROMISC, IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in case of set_rx_mode). These callbacks can be invoked from BH context without the rtnl_mutex by dev_mc_add/dev_mc_delete, which makes reading the device flags and promiscous/allmulti count racy. For real hardware drivers that just commit all changes to the hardware this is not a real problem since the stack guarantees to call them for every change, so at least the final call will not race and commit the correct configuration to the hardware. For software devices that want to synchronize promiscous and multicast state to an underlying device however this can cause corruption of the underlying device's flags or promisc/allmulti counts. When the software device is concurrently put in promiscous or allmulti mode while set_multicast_list is invoked from bottem half context, the device might synchronize the change to the underlying device without holding the rtnl_mutex, which races with concurrent changes to the underlying device. Add a dev->change_rx_flags hook that is invoked when any of the flags that affect rx filtering change (under the rtnl_mutex), which allows drivers to perform synchronization immediately and only synchronize the address lists in set_multicast_list/set_rx_mode. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 18:51:31 -07:00
[NET]: Add net_device change_rx_mode callback Currently the set_multicast_list (and set_rx_mode) callbacks are responsible for configuring the device according to the IFF_PROMISC, IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in case of set_rx_mode). These callbacks can be invoked from BH context without the rtnl_mutex by dev_mc_add/dev_mc_delete, which makes reading the device flags and promiscous/allmulti count racy. For real hardware drivers that just commit all changes to the hardware this is not a real problem since the stack guarantees to call them for every change, so at least the final call will not race and commit the correct configuration to the hardware. For software devices that want to synchronize promiscous and multicast state to an underlying device however this can cause corruption of the underlying device's flags or promisc/allmulti counts. When the software device is concurrently put in promiscous or allmulti mode while set_multicast_list is invoked from bottem half context, the device might synchronize the change to the underlying device without holding the rtnl_mutex, which races with concurrent changes to the underlying device. Add a dev->change_rx_flags hook that is invoked when any of the flags that affect rx filtering change (under the rtnl_mutex), which allows drivers to perform synchronization immediately and only synchronize the address lists in set_multicast_list/set_rx_mode. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 18:51:31 -07:00
[NET]: Add net_device change_rx_mode callback Currently the set_multicast_list (and set_rx_mode) callbacks are responsible for configuring the device according to the IFF_PROMISC, IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in case of set_rx_mode). These callbacks can be invoked from BH context without the rtnl_mutex by dev_mc_add/dev_mc_delete, which makes reading the device flags and promiscous/allmulti count racy. For real hardware drivers that just commit all changes to the hardware this is not a real problem since the stack guarantees to call them for every change, so at least the final call will not race and commit the correct configuration to the hardware. For software devices that want to synchronize promiscous and multicast state to an underlying device however this can cause corruption of the underlying device's flags or promisc/allmulti counts. When the software device is concurrently put in promiscous or allmulti mode while set_multicast_list is invoked from bottem half context, the device might synchronize the change to the underlying device without holding the rtnl_mutex, which races with concurrent changes to the underlying device. Add a dev->change_rx_flags hook that is invoked when any of the flags that affect rx filtering change (under the rtnl_mutex), which allows drivers to perform synchronization immediately and only synchronize the address lists in set_multicast_list/set_rx_mode. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 18:51:31 -07:00
[NET]: Add net_device change_rx_mode callback Currently the set_multicast_list (and set_rx_mode) callbacks are responsible for configuring the device according to the IFF_PROMISC, IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in case of set_rx_mode). These callbacks can be invoked from BH context without the rtnl_mutex by dev_mc_add/dev_mc_delete, which makes reading the device flags and promiscous/allmulti count racy. For real hardware drivers that just commit all changes to the hardware this is not a real problem since the stack guarantees to call them for every change, so at least the final call will not race and commit the correct configuration to the hardware. For software devices that want to synchronize promiscous and multicast state to an underlying device however this can cause corruption of the underlying device's flags or promisc/allmulti counts. When the software device is concurrently put in promiscous or allmulti mode while set_multicast_list is invoked from bottem half context, the device might synchronize the change to the underlying device without holding the rtnl_mutex, which races with concurrent changes to the underlying device. Add a dev->change_rx_flags hook that is invoked when any of the flags that affect rx filtering change (under the rtnl_mutex), which allows drivers to perform synchronization immediately and only synchronize the address lists in set_multicast_list/set_rx_mode. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 18:51:31 -07:00
[NET]: Add net_device change_rx_mode callback Currently the set_multicast_list (and set_rx_mode) callbacks are responsible for configuring the device according to the IFF_PROMISC, IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in case of set_rx_mode). These callbacks can be invoked from BH context without the rtnl_mutex by dev_mc_add/dev_mc_delete, which makes reading the device flags and promiscous/allmulti count racy. For real hardware drivers that just commit all changes to the hardware this is not a real problem since the stack guarantees to call them for every change, so at least the final call will not race and commit the correct configuration to the hardware. For software devices that want to synchronize promiscous and multicast state to an underlying device however this can cause corruption of the underlying device's flags or promisc/allmulti counts. When the software device is concurrently put in promiscous or allmulti mode while set_multicast_list is invoked from bottem half context, the device might synchronize the change to the underlying device without holding the rtnl_mutex, which races with concurrent changes to the underlying device. Add a dev->change_rx_flags hook that is invoked when any of the flags that affect rx filtering change (under the rtnl_mutex), which allows drivers to perform synchronization immediately and only synchronize the address lists in set_multicast_list/set_rx_mode. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-14 18:51:31 -07:00
net: fix rtnl notification in atomic context commit 991fb3f74c "dev: always advertise rx_flags changes via netlink" introduced rtnl notification from __dev_set_promiscuity(), which can be called in atomic context. Steps to reproduce: ip tuntap add dev tap1 mode tap ifconfig tap1 up tcpdump -nei tap1 & ip tuntap del dev tap1 mode tap [ 271.627994] device tap1 left promiscuous mode [ 271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940 [ 271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip [ 271.677525] INFO: lockdep is turned off. [ 271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G W 3.12.0-rc3+ #73 [ 271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 271.731254] ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428 [ 271.760261] ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8 [ 271.790683] 0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8 [ 271.822332] Call Trace: [ 271.838234] [<ffffffff817544e5>] dump_stack+0x55/0x76 [ 271.854446] [<ffffffff8108bad1>] __might_sleep+0x181/0x240 [ 271.870836] [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0 [ 271.887076] [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0 [ 271.903368] [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0 [ 271.919716] [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0 [ 271.936088] [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0 [ 271.952504] [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0 [ 271.968902] [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100 [ 271.985302] [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0 [ 272.001642] [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0 [ 272.017917] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.033961] [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50 [ 272.049855] [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0 [ 272.065494] [<ffffffff81732052>] packet_notifier+0x1b2/0x380 [ 272.080915] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.096009] [<ffffffff81761c66>] notifier_call_chain+0x66/0x150 [ 272.110803] [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10 [ 272.125468] [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20 [ 272.139984] [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70 [ 272.154523] [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20 [ 272.168552] [<ffffffff816224c5>] rollback_registered_many+0x145/0x240 [ 272.182263] [<ffffffff81622641>] rollback_registered+0x31/0x40 [ 272.195369] [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90 [ 272.208230] [<ffffffff81547ca0>] __tun_detach+0x140/0x340 [ 272.220686] [<ffffffff81547ed6>] tun_chr_close+0x36/0x60 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:02:42 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
net: Delay default_device_exit_batch until no devices are unregistering v2 There is currently serialization network namespaces exiting and network devices exiting as the final part of netdev_run_todo does not happen under the rtnl_lock. This is compounded by the fact that the only list of devices unregistering in netdev_run_todo is local to the netdev_run_todo. This lack of serialization in extreme cases results in network devices unregistering in netdev_run_todo after the loopback device of their network namespace has been freed (making dst_ifdown unsafe), and after the their network namespace has exited (making the NETDEV_UNREGISTER, and NETDEV_UNREGISTER_FINAL callbacks unsafe). Add the missing serialization by a per network namespace count of how many network devices are unregistering and having a wait queue that is woken up whenever the count is decreased. The count and wait queue allow default_device_exit_batch to wait until all of the unregistration activity for a network namespace has finished before proceeding to unregister the loopback device and then allowing the network namespace to exit. Only a single global wait queue is used because there is a single global lock, and there is a single waiter, per network namespace wait queues would be a waste of resources. The per network namespace count of unregistering devices gives a progress guarantee because the number of network devices unregistering in an exiting network namespace must ultimately drop to zero (assuming network device unregistration completes). The basic logic remains the same as in v1. This patch is now half comment and half rtnl_lock_unregistering an expanded version of wait_event performs no extra work in the common case where no network devices are unregistering when we get to default_device_exit_batch. Reported-by: Francesco Ruggeri <fruggeri@aristanetworks.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-23 21:19:49 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
xps: Transmit Packet Steering This patch implements transmit packet steering (XPS) for multiqueue devices. XPS selects a transmit queue during packet transmission based on configuration. This is done by mapping the CPU transmitting the packet to a queue. This is the transmit side analogue to RPS-- where RPS is selecting a CPU based on receive queue, XPS selects a queue based on the CPU (previously there was an XPS patch from Eric Dumazet, but that might more appropriately be called transmit completion steering). Each transmit queue can be associated with a number of CPUs which will use the queue to send packets. This is configured as a CPU mask on a per queue basis in: /sys/class/net/eth<n>/queues/tx-<n>/xps_cpus The mappings are stored per device in an inverted data structure that maps CPUs to queues. In the netdevice structure this is an array of num_possible_cpu structures where each structure holds and array of queue_indexes for queues which that CPU can use. The benefits of XPS are improved locality in the per queue data structures. Also, transmit completions are more likely to be done nearer to the sending thread, so this should promote locality back to the socket on free (e.g. UDP). The benefits of XPS are dependent on cache hierarchy, application load, and other factors. XPS would nominally be configured so that a queue would only be shared by CPUs which are sharing a cache, the degenerative configuration woud be that each CPU has it's own queue. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. bnx2x on 16 core AMD XPS (16 queues, 1 TX queue per CPU) 1234K at 100% CPU No XPS (16 queues) 996K at 100% CPU Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-21 13:17:27 +00:00
net:set valid name before calling ndo_init() In commit 1c5cae815d19 (net: call dev_alloc_name from register_netdevice), a bug of bonding was involved, see example 1 and 2. In register_netdevice(), the name of net_device is not valid until dev_get_valid_name() is called. But dev->netdev_ops->ndo_init(that is bond_init) is called before dev_get_valid_name(), and it uses the invalid name of net_device. I think register_netdevice() should make sure that the name of net_device is valid before calling ndo_init(). example 1: modprobe bonding ls /proc/net/bonding/bond%d ps -eLf root 3398 2 3398 0 1 21:34 ? 00:00:00 [bond%d] example 2: modprobe bonding max_bonds=3 [ 170.100292] bonding: Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011) [ 170.101090] bonding: Warning: either miimon or arp_interval and arp_ip_target module parameters must be specified, otherwise bonding will not detect link failures! see bonding.txt for details. [ 170.102469] ------------[ cut here ]------------ [ 170.103150] WARNING: at /home/pwp/net-next-2.6/fs/proc/generic.c:586 proc_register+0x126/0x157() [ 170.104075] Hardware name: VirtualBox [ 170.105065] proc_dir_entry 'bonding/bond%d' already registered [ 170.105613] Modules linked in: bonding(+) sunrpc ipv6 uinput microcode ppdev parport_pc parport joydev e1000 pcspkr i2c_piix4 i2c_core [last unloaded: bonding] [ 170.108397] Pid: 3457, comm: modprobe Not tainted 2.6.39-rc2+ #14 [ 170.108935] Call Trace: [ 170.109382] [<c0438f3b>] warn_slowpath_common+0x6a/0x7f [ 170.109911] [<c051a42a>] ? proc_register+0x126/0x157 [ 170.110329] [<c0438fc3>] warn_slowpath_fmt+0x2b/0x2f [ 170.110846] [<c051a42a>] proc_register+0x126/0x157 [ 170.111870] [<c051a4dd>] proc_create_data+0x82/0x98 [ 170.112335] [<f94e6af6>] bond_create_proc_entry+0x3f/0x73 [bonding] [ 170.112905] [<f94dd806>] bond_init+0x77/0xa5 [bonding] [ 170.113319] [<c0721ac6>] register_netdevice+0x8c/0x1d3 [ 170.113848] [<f94e0e30>] bond_create+0x6c/0x90 [bonding] [ 170.114322] [<f94f4763>] bonding_init+0x763/0x7b1 [bonding] [ 170.114879] [<c0401240>] do_one_initcall+0x76/0x122 [ 170.115317] [<f94f4000>] ? 0xf94f3fff [ 170.115799] [<c0463f1e>] sys_init_module+0x1286/0x140d [ 170.116879] [<c07c6d9f>] sysenter_do_call+0x12/0x28 [ 170.117404] ---[ end trace 64e4fac3ae5fff1a ]--- [ 170.117924] bond%d: Warning: failed to register to debugfs [ 170.128728] ------------[ cut here ]------------ [ 170.129360] WARNING: at /home/pwp/net-next-2.6/fs/proc/generic.c:586 proc_register+0x126/0x157() [ 170.130323] Hardware name: VirtualBox [ 170.130797] proc_dir_entry 'bonding/bond%d' already registered [ 170.131315] Modules linked in: bonding(+) sunrpc ipv6 uinput microcode ppdev parport_pc parport joydev e1000 pcspkr i2c_piix4 i2c_core [last unloaded: bonding] [ 170.133731] Pid: 3457, comm: modprobe Tainted: G W 2.6.39-rc2+ #14 [ 170.134308] Call Trace: [ 170.134743] [<c0438f3b>] warn_slowpath_common+0x6a/0x7f [ 170.135305] [<c051a42a>] ? proc_register+0x126/0x157 [ 170.135820] [<c0438fc3>] warn_slowpath_fmt+0x2b/0x2f [ 170.137168] [<c051a42a>] proc_register+0x126/0x157 [ 170.137700] [<c051a4dd>] proc_create_data+0x82/0x98 [ 170.138174] [<f94e6af6>] bond_create_proc_entry+0x3f/0x73 [bonding] [ 170.138745] [<f94dd806>] bond_init+0x77/0xa5 [bonding] [ 170.139278] [<c0721ac6>] register_netdevice+0x8c/0x1d3 [ 170.139828] [<f94e0e30>] bond_create+0x6c/0x90 [bonding] [ 170.140361] [<f94f4763>] bonding_init+0x763/0x7b1 [bonding] [ 170.140927] [<c0401240>] do_one_initcall+0x76/0x122 [ 170.141494] [<f94f4000>] ? 0xf94f3fff [ 170.141975] [<c0463f1e>] sys_init_module+0x1286/0x140d [ 170.142463] [<c07c6d9f>] sysenter_do_call+0x12/0x28 [ 170.142974] ---[ end trace 64e4fac3ae5fff1b ]--- [ 170.144949] bond%d: Warning: failed to register to debugfs Signed-off-by: Weiping Pan <panweiping3@gmail.com> Reviewed-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-12 15:46:56 +00:00
net: Allow no-cache copy from user on transmit This patch uses __copy_from_user_nocache on transmit to bypass data cache for a performance improvement. skb_add_data_nocache and skb_copy_to_page_nocache can be called by sendmsg functions to use this feature, initial support is in tcp_sendmsg. This functionality is configurable per device using ethtool. Presumably, this feature would only be useful when the driver does not touch the data. The feature is turned on by default if a device indicates that it does some form of checksum offload; it is off by default for devices that do no checksum offload or indicate no checksum is necessary. For the former case copy-checksum is probably done anyway, in the latter case the device is likely loopback in which case the no cache copy is probably not beneficial. This patch was tested using 200 instances of netperf TCP_RR with 1400 byte request and one byte reply. Platform is 16 core AMD x86. No-cache copy disabled: 672703 tps, 97.13% utilization 50/90/99% latency:244.31 484.205 1028.41 No-cache copy enabled: 702113 tps, 96.16% utilization, 50/90/99% latency 238.56 467.56 956.955 Using 14000 byte request and response sizes demonstrate the effects more dramatically: No-cache copy disabled: 79571 tps, 34.34 %utlization 50/90/95% latency 1584.46 2319.59 5001.76 No-cache copy enabled: 83856 tps, 34.81% utilization 50/90/95% latency 2508.42 2622.62 2735.88 Note especially the effect on latency tail (95th percentile). This seems to provide a nice performance improvement and is consistent in the tests I ran. Presumably, this would provide the greatest benfits in the presence of an application workload stressing the cache and a lot of transmit data happening. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-04 22:30:30 -07:00
MPLS: Add limited GSO support In the case where a non-MPLS packet is received and an MPLS stack is added it may well be the case that the original skb is GSO but the NIC used for transmit does not support GSO of MPLS packets. The aim of this code is to provide GSO in software for MPLS packets whose skbs are GSO. SKB Usage: When an implementation adds an MPLS stack to a non-MPLS packet it should do the following to skb metadata: * Set skb->inner_protocol to the old non-MPLS ethertype of the packet. skb->inner_protocol is added by this patch. * Set skb->protocol to the new MPLS ethertype of the packet. * Set skb->network_header to correspond to the end of the L3 header, including the MPLS label stack. I have posted a patch, "[PATCH v3.29] datapath: Add basic MPLS support to kernel" which adds MPLS support to the kernel datapath of Open vSwtich. That patch sets the above requirements in datapath/actions.c:push_mpls() and was used to exercise this code. The datapath patch is against the Open vSwtich tree but it is intended that it be added to the Open vSwtich code present in the mainline Linux kernel at some point. Features: I believe that the approach that I have taken is at least partially consistent with the handling of other protocols. Jesse, I understand that you have some ideas here. I am more than happy to change my implementation. This patch adds dev->mpls_features which may be used by devices to advertise features supported for MPLS packets. A new NETIF_F_MPLS_GSO feature is added for devices which support hardware MPLS GSO offload. Currently no devices support this and MPLS GSO always falls back to software. Alternate Implementation: One possible alternate implementation is to teach netif_skb_features() and skb_network_protocol() about MPLS, in a similar way to their understanding of VLANs. I believe this would avoid the need for net/mpls/mpls_gso.c and in particular the calls to __skb_push() and __skb_push() in mpls_gso_segment(). I have decided on the implementation in this patch as it should not introduce any overhead in the case where mpls_gso is not compiled into the kernel or inserted as a module. MPLS GSO suggested by Jesse Gross. Based in part on "v4 GRE: Add TCP segmentation offload for GRE" by Pravin B Shelar. Cc: Jesse Gross <jesse@nicira.com> Cc: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-23 21:02:52 +00:00
net: Set device operstate at registration time The operstate of a device is initially IF_OPER_UNKNOWN and is updated asynchronously by linkwatch after each change of carrier state reported by the driver. The default carrier state of a net device is on, and this will never be changed on drivers that do not support carrier detection, thus the operstate remains IF_OPER_UNKNOWN. For devices that do support carrier detection, the driver must set the carrier state to off initially, then poll the hardware state when the device is opened. However, we must not activate linkwatch for a unregistered device, and commit b473001 ('net: Do not fire linkwatch events until the device is registered.') ensured that we don't. But this means that the operstate for many devices that support carrier detection remains IF_OPER_UNKNOWN when it should be IF_OPER_DOWN. The same issue exists with the dormant state. The proper initialisation sequence, avoiding a race with opening of the device, is: rtnl_lock(); rc = register_netdevice(dev); if (rc) goto out_unlock; netif_carrier_off(dev); /* or netif_dormant_on(dev) */ rtnl_unlock(); but it seems silly that this should have to be repeated in so many drivers. Further, the operstate seen immediately after opening the device may still be IF_OPER_UNKNOWN due to the asynchronous nature of linkwatch. Commit 22604c8 ('net: Fix for initial link state in 2.6.28') attempted to fix this by setting the operstate synchronously, but it was reverted as it could lead to deadlock. This initialises the operstate synchronously at registration time only. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-20 22:16:51 +01:00
[NET]: Fix free_netdev on register_netdev failure. Point 1: The unregistering of a network device schedule a netdev_run_todo. This function calls dev->destructor when it is set and the destructor calls free_netdev. Point 2: In the case of an initialization of a network device the usual code is: * alloc_netdev * register_netdev -> if this one fails, call free_netdev and exit with error. Point 3: In the register_netdevice function at the later state, when the device is at the registered state, a call to the netdevice_notifiers is made. If one of the notification falls into an error, a rollback to the registered state is done using unregister_netdevice. Conclusion: When a network device fails to register during initialization because one network subsystem returned an error during a notification call chain, the network device is freed twice because of fact 1 and fact 2. The second free_netdev will be done with an invalid pointer. Proposed solution: The following patch move all the code of unregister_netdevice *except* the call to net_set_todo, to a new function "rollback_registered". The following functions are changed in this way: * register_netdevice: calls rollback_registered when a notification fails * unregister_netdevice: calls rollback_register + net_set_todo, the call order to net_set_todo is changed because it is the latest now. Since it justs add an element to a list that should not break anything. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 15:38:18 -07:00
net: fix rtnl notification in atomic context commit 991fb3f74c "dev: always advertise rx_flags changes via netlink" introduced rtnl notification from __dev_set_promiscuity(), which can be called in atomic context. Steps to reproduce: ip tuntap add dev tap1 mode tap ifconfig tap1 up tcpdump -nei tap1 & ip tuntap del dev tap1 mode tap [ 271.627994] device tap1 left promiscuous mode [ 271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940 [ 271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip [ 271.677525] INFO: lockdep is turned off. [ 271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G W 3.12.0-rc3+ #73 [ 271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 271.731254] ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428 [ 271.760261] ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8 [ 271.790683] 0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8 [ 271.822332] Call Trace: [ 271.838234] [<ffffffff817544e5>] dump_stack+0x55/0x76 [ 271.854446] [<ffffffff8108bad1>] __might_sleep+0x181/0x240 [ 271.870836] [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0 [ 271.887076] [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0 [ 271.903368] [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0 [ 271.919716] [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0 [ 271.936088] [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0 [ 271.952504] [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0 [ 271.968902] [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100 [ 271.985302] [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0 [ 272.001642] [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0 [ 272.017917] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.033961] [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50 [ 272.049855] [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0 [ 272.065494] [<ffffffff81732052>] packet_notifier+0x1b2/0x380 [ 272.080915] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.096009] [<ffffffff81761c66>] notifier_call_chain+0x66/0x150 [ 272.110803] [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10 [ 272.125468] [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20 [ 272.139984] [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70 [ 272.154523] [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20 [ 272.168552] [<ffffffff816224c5>] rollback_registered_many+0x145/0x240 [ 272.182263] [<ffffffff81622641>] rollback_registered+0x31/0x40 [ 272.195369] [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90 [ 272.208230] [<ffffffff81547ca0>] __tun_detach+0x140/0x340 [ 272.220686] [<ffffffff81547ed6>] tun_chr_close+0x36/0x60 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:02:42 -07:00
linkwatch: linkwatch_forget_dev() to speedup device dismantle Herbert Xu a écrit : > On Tue, Nov 17, 2009 at 04:26:04AM -0800, David Miller wrote: >> Really, the link watch stuff is just due for a redesign. I don't >> think a simple hack is going to cut it this time, sorry Eric :-) > > I have no objections against any redesigns, but since the only > caller of linkwatch_forget_dev runs in process context with the > RTNL, it could also legally emit those events. Thanks guys, here an updated version then, before linkwatch surgery ? In this version, I force the event to be sent synchronously. [PATCH net-next-2.6] linkwatch: linkwatch_forget_dev() to speedup device dismantle time ip link del eth3.103 ; time ip link del eth3.104 ; time ip link del eth3.105 real 0m0.266s user 0m0.000s sys 0m0.001s real 0m0.770s user 0m0.000s sys 0m0.000s real 0m1.022s user 0m0.000s sys 0m0.000s One problem of current schem in vlan dismantle phase is the holding of device done by following chain : vlan_dev_stop() -> netif_carrier_off(dev) -> linkwatch_fire_event(dev) -> dev_hold() ... And __linkwatch_run_queue() runs up to one second later... A generic fix to this problem is to add a linkwatch_forget_dev() method to unlink the device from the list of watched devices. dev->link_watch_next becomes dev->link_watch_list (and use a bit more memory), to be able to unlink device in O(1). After patch : time ip link del eth3.103 ; time ip link del eth3.104 ; time ip link del eth3.105 real 0m0.024s user 0m0.000s sys 0m0.000s real 0m0.032s user 0m0.000s sys 0m0.001s real 0m0.033s user 0m0.000s sys 0m0.000s Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-17 05:59:21 +00:00
net: Delay default_device_exit_batch until no devices are unregistering v2 There is currently serialization network namespaces exiting and network devices exiting as the final part of netdev_run_todo does not happen under the rtnl_lock. This is compounded by the fact that the only list of devices unregistering in netdev_run_todo is local to the netdev_run_todo. This lack of serialization in extreme cases results in network devices unregistering in netdev_run_todo after the loopback device of their network namespace has been freed (making dst_ifdown unsafe), and after the their network namespace has exited (making the NETDEV_UNREGISTER, and NETDEV_UNREGISTER_FINAL callbacks unsafe). Add the missing serialization by a per network namespace count of how many network devices are unregistering and having a wait queue that is woken up whenever the count is decreased. The count and wait queue allow default_device_exit_batch to wait until all of the unregistration activity for a network namespace has finished before proceeding to unregister the loopback device and then allowing the network namespace to exit. Only a single global wait queue is used because there is a single global lock, and there is a single waiter, per network namespace wait queues would be a waste of resources. The per network namespace count of unregistering devices gives a progress guarantee because the number of network devices unregistering in an exiting network namespace must ultimately drop to zero (assuming network device unregistration completes). The basic logic remains the same as in v1. This patch is now half comment and half rtnl_lock_unregistering an expanded version of wait_event performs no extra work in the common case where no network devices are unregistering when we get to default_device_exit_batch. Reported-by: Francesco Ruggeri <fruggeri@aristanetworks.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-23 21:19:49 -07:00
net: add adj_list to save only neighbours Currently, we distinguish neighbours (first-level linked devices) from non-neighbours by the neighbour bool in the netdev_adjacent. This could be quite time-consuming in case we would like to traverse *only* through neighbours - cause we'd have to traverse through all devices and check for this flag, and in a (quite common) scenario where we have lots of vlans on top of bridge, which is on top of a bond - the bonding would have to go through all those vlans to get its upper neighbour linked devices. This situation is really unpleasant, cause there are already a lot of cases when a device with slaves needs to go through them in hot path. To fix this, introduce a new upper/lower device lists structure - adj_list, which contains only the neighbours. It works always in pair with the all_adj_list structure (renamed from upper/lower_dev_list), i.e. both of them contain the same links, only that all_adj_list contains also non-neighbour device links. It's really a small change visible, currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't change the main linked logic at all. Also, add some comments a fix a name collision in netdev_for_each_upper_dev_rcu() and rework the naming by the following rules: netdev_(all_)(upper|lower)_* If "all_" is present, then we work with the whole list of upper/lower devices, otherwise - only with direct neighbours. Uninline functions - to get better stack traces. CC: "David S. Miller" <davem@davemloft.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jiri@resnulli.us> CC: Alexander Duyck <alexander.h.duyck@intel.com> CC: Cong Wang <amwang@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-25 09:20:07 +02:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: Add Generic Receive Offload infrastructure This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-15 23:38:52 -08:00
net: use synchronize_rcu_expedited() synchronize_rcu() is very slow in various situations (HZ=100, CONFIG_NO_HZ=y, CONFIG_PREEMPT=n) Extract from my (mostly idle) 8 core machine : synchronize_rcu() in 99985 us synchronize_rcu() in 79982 us synchronize_rcu() in 87612 us synchronize_rcu() in 79827 us synchronize_rcu() in 109860 us synchronize_rcu() in 98039 us synchronize_rcu() in 89841 us synchronize_rcu() in 79842 us synchronize_rcu() in 80151 us synchronize_rcu() in 119833 us synchronize_rcu() in 99858 us synchronize_rcu() in 73999 us synchronize_rcu() in 79855 us synchronize_rcu() in 79853 us When we hold RTNL mutex, we would like to spend some cpu cycles but not block too long other processes waiting for this mutex. We also want to setup/dismantle network features as fast as possible at boot/shutdown time. This patch makes synchronize_net() call the expedited version if RTNL is locked. synchronize_rcu_expedited() typical delay is about 20 us on my machine. synchronize_rcu_expedited() in 18 us synchronize_rcu_expedited() in 18 us synchronize_rcu_expedited() in 18 us synchronize_rcu_expedited() in 18 us synchronize_rcu_expedited() in 20 us synchronize_rcu_expedited() in 16 us synchronize_rcu_expedited() in 20 us synchronize_rcu_expedited() in 18 us synchronize_rcu_expedited() in 18 us Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com> CC: Ben Greear <greearb@candelatech.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-23 23:07:32 +00:00
net: fix rtnl notification in atomic context commit 991fb3f74c "dev: always advertise rx_flags changes via netlink" introduced rtnl notification from __dev_set_promiscuity(), which can be called in atomic context. Steps to reproduce: ip tuntap add dev tap1 mode tap ifconfig tap1 up tcpdump -nei tap1 & ip tuntap del dev tap1 mode tap [ 271.627994] device tap1 left promiscuous mode [ 271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940 [ 271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip [ 271.677525] INFO: lockdep is turned off. [ 271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G W 3.12.0-rc3+ #73 [ 271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 271.731254] ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428 [ 271.760261] ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8 [ 271.790683] 0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8 [ 271.822332] Call Trace: [ 271.838234] [<ffffffff817544e5>] dump_stack+0x55/0x76 [ 271.854446] [<ffffffff8108bad1>] __might_sleep+0x181/0x240 [ 271.870836] [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0 [ 271.887076] [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0 [ 271.903368] [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0 [ 271.919716] [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0 [ 271.936088] [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0 [ 271.952504] [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0 [ 271.968902] [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100 [ 271.985302] [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0 [ 272.001642] [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0 [ 272.017917] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.033961] [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50 [ 272.049855] [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0 [ 272.065494] [<ffffffff81732052>] packet_notifier+0x1b2/0x380 [ 272.080915] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.096009] [<ffffffff81761c66>] notifier_call_chain+0x66/0x150 [ 272.110803] [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10 [ 272.125468] [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20 [ 272.139984] [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70 [ 272.154523] [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20 [ 272.168552] [<ffffffff816224c5>] rollback_registered_many+0x145/0x240 [ 272.182263] [<ffffffff81622641>] rollback_registered+0x31/0x40 [ 272.195369] [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90 [ 272.208230] [<ffffffff81547ca0>] __tun_detach+0x140/0x340 [ 272.220686] [<ffffffff81547ed6>] tun_chr_close+0x36/0x60 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:02:42 -07:00
net: dev_change_net_namespace: send a KOBJ_REMOVED/KOBJ_ADD When a new nic is created in namespace ns1, the kernel sends a KOBJ_ADD uevent to ns1. When the nic is moved to ns2, we only send a KOBJ_MOVE to ns2, and nothing to ns1. This patch changes that behavior so that when moving a nic from ns1 to ns2, we send a KOBJ_REMOVED to ns1 and KOBJ_ADD to ns2. (The KOBJ_MOVE is still sent to ns2). The effects of this can be seen when starting and stopping containers in an upstart based host. Lxc will create a pair of veth nics, the kernel sends KOBJ_ADD, and upstart starts network-instance jobs for each. When one nic is moved to the container, because no KOBJ_REMOVED event is received, the network-instance job for that veth never goes away. This was reported at https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1065589 With this patch the networ-instance jobs properly go away. The other oddness solved here is that if a nic is passed into a running upstart-based container, without this patch no network-instance job is started in the container. But when the container creates a new nic itself (ip link add new type veth) then network-interface jobs are created. With this patch, behavior comes in line with a regular host. v2: also send KOBJ_ADD to new netns. There will then be a _MOVE event from the device_rename() call, but that should be innocuous. Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 16:17:12 +00:00
net: dev_change_net_namespace: send a KOBJ_REMOVED/KOBJ_ADD When a new nic is created in namespace ns1, the kernel sends a KOBJ_ADD uevent to ns1. When the nic is moved to ns2, we only send a KOBJ_MOVE to ns2, and nothing to ns1. This patch changes that behavior so that when moving a nic from ns1 to ns2, we send a KOBJ_REMOVED to ns1 and KOBJ_ADD to ns2. (The KOBJ_MOVE is still sent to ns2). The effects of this can be seen when starting and stopping containers in an upstart based host. Lxc will create a pair of veth nics, the kernel sends KOBJ_ADD, and upstart starts network-instance jobs for each. When one nic is moved to the container, because no KOBJ_REMOVED event is received, the network-instance job for that veth never goes away. This was reported at https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1065589 With this patch the networ-instance jobs properly go away. The other oddness solved here is that if a nic is passed into a running upstart-based container, without this patch no network-instance job is started in the container. But when the container creates a new nic itself (ip link add new type veth) then network-interface jobs are created. With this patch, behavior comes in line with a regular host. v2: also send KOBJ_ADD to new netns. There will then be a _MOVE event from the device_rename() call, but that should be innocuous. Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 16:17:12 +00:00
net: dev_change_net_namespace: send a KOBJ_REMOVED/KOBJ_ADD When a new nic is created in namespace ns1, the kernel sends a KOBJ_ADD uevent to ns1. When the nic is moved to ns2, we only send a KOBJ_MOVE to ns2, and nothing to ns1. This patch changes that behavior so that when moving a nic from ns1 to ns2, we send a KOBJ_REMOVED to ns1 and KOBJ_ADD to ns2. (The KOBJ_MOVE is still sent to ns2). The effects of this can be seen when starting and stopping containers in an upstart based host. Lxc will create a pair of veth nics, the kernel sends KOBJ_ADD, and upstart starts network-instance jobs for each. When one nic is moved to the container, because no KOBJ_REMOVED event is received, the network-instance job for that veth never goes away. This was reported at https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1065589 With this patch the networ-instance jobs properly go away. The other oddness solved here is that if a nic is passed into a running upstart-based container, without this patch no network-instance job is started in the container. But when the container creates a new nic itself (ip link add new type veth) then network-interface jobs are created. With this patch, behavior comes in line with a regular host. v2: also send KOBJ_ADD to new netns. There will then be a _MOVE event from the device_rename() call, but that should be innocuous. Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 16:17:12 +00:00
net: dev_change_net_namespace: send a KOBJ_REMOVED/KOBJ_ADD When a new nic is created in namespace ns1, the kernel sends a KOBJ_ADD uevent to ns1. When the nic is moved to ns2, we only send a KOBJ_MOVE to ns2, and nothing to ns1. This patch changes that behavior so that when moving a nic from ns1 to ns2, we send a KOBJ_REMOVED to ns1 and KOBJ_ADD to ns2. (The KOBJ_MOVE is still sent to ns2). The effects of this can be seen when starting and stopping containers in an upstart based host. Lxc will create a pair of veth nics, the kernel sends KOBJ_ADD, and upstart starts network-instance jobs for each. When one nic is moved to the container, because no KOBJ_REMOVED event is received, the network-instance job for that veth never goes away. This was reported at https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1065589 With this patch the networ-instance jobs properly go away. The other oddness solved here is that if a nic is passed into a running upstart-based container, without this patch no network-instance job is started in the container. But when the container creates a new nic itself (ip link add new type veth) then network-interface jobs are created. With this patch, behavior comes in line with a regular host. v2: also send KOBJ_ADD to new netns. There will then be a _MOVE event from the device_rename() call, but that should be innocuous. Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 16:17:12 +00:00
net: fix rtnl notification in atomic context commit 991fb3f74c "dev: always advertise rx_flags changes via netlink" introduced rtnl notification from __dev_set_promiscuity(), which can be called in atomic context. Steps to reproduce: ip tuntap add dev tap1 mode tap ifconfig tap1 up tcpdump -nei tap1 & ip tuntap del dev tap1 mode tap [ 271.627994] device tap1 left promiscuous mode [ 271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940 [ 271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip [ 271.677525] INFO: lockdep is turned off. [ 271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G W 3.12.0-rc3+ #73 [ 271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 271.731254] ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428 [ 271.760261] ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8 [ 271.790683] 0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8 [ 271.822332] Call Trace: [ 271.838234] [<ffffffff817544e5>] dump_stack+0x55/0x76 [ 271.854446] [<ffffffff8108bad1>] __might_sleep+0x181/0x240 [ 271.870836] [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0 [ 271.887076] [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0 [ 271.903368] [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0 [ 271.919716] [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0 [ 271.936088] [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0 [ 271.952504] [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0 [ 271.968902] [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100 [ 271.985302] [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0 [ 272.001642] [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0 [ 272.017917] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.033961] [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50 [ 272.049855] [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0 [ 272.065494] [<ffffffff81732052>] packet_notifier+0x1b2/0x380 [ 272.080915] [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380 [ 272.096009] [<ffffffff81761c66>] notifier_call_chain+0x66/0x150 [ 272.110803] [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10 [ 272.125468] [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20 [ 272.139984] [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70 [ 272.154523] [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20 [ 272.168552] [<ffffffff816224c5>] rollback_registered_many+0x145/0x240 [ 272.182263] [<ffffffff81622641>] rollback_registered+0x31/0x40 [ 272.195369] [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90 [ 272.208230] [<ffffffff81547ca0>] __tun_detach+0x140/0x340 [ 272.220686] [<ffffffff81547ed6>] tun_chr_close+0x36/0x60 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:02:42 -07:00
rfs: Receive Flow Steering This patch implements receive flow steering (RFS). RFS steers received packets for layer 3 and 4 processing to the CPU where the application for the corresponding flow is running. RFS is an extension of Receive Packet Steering (RPS). The basic idea of RFS is that when an application calls recvmsg (or sendmsg) the application's running CPU is stored in a hash table that is indexed by the connection's rxhash which is stored in the socket structure. The rxhash is passed in skb's received on the connection from netif_receive_skb. For each received packet, the associated rxhash is used to look up the CPU in the hash table, if a valid CPU is set then the packet is steered to that CPU using the RPS mechanisms. The convolution of the simple approach is that it would potentially allow OOO packets. If threads are thrashing around CPUs or multiple threads are trying to read from the same sockets, a quickly changing CPU value in the hash table could cause rampant OOO packets-- we consider this a non-starter. To avoid OOO packets, this solution implements two types of hash tables: rps_sock_flow_table and rps_dev_flow_table. rps_sock_table is a global hash table. Each entry is just a CPU number and it is populated in recvmsg and sendmsg as described above. This table contains the "desired" CPUs for flows. rps_dev_flow_table is specific to each device queue. Each entry contains a CPU and a tail queue counter. The CPU is the "current" CPU for a matching flow. The tail queue counter holds the value of a tail queue counter for the associated CPU's backlog queue at the time of last enqueue for a flow matching the entry. Each backlog queue has a queue head counter which is incremented on dequeue, and so a queue tail counter is computed as queue head count + queue length. When a packet is enqueued on a backlog queue, the current value of the queue tail counter is saved in the hash entry of the rps_dev_flow_table. And now the trick: when selecting the CPU for RPS (get_rps_cpu) the rps_sock_flow table and the rps_dev_flow table for the RX queue are consulted. When the desired CPU for the flow (found in the rps_sock_flow table) does not match the current CPU (found in the rps_dev_flow table), the current CPU is changed to the desired CPU if one of the following is true: - The current CPU is unset (equal to RPS_NO_CPU) - Current CPU is offline - The current CPU's queue head counter >= queue tail counter in the rps_dev_flow table. This checks if the queue tail has advanced beyond the last packet that was enqueued using this table entry. This guarantees that all packets queued using this entry have been dequeued, thus preserving in order delivery. Making each queue have its own rps_dev_flow table has two advantages: 1) the tail queue counters will be written on each receive, so keeping the table local to interrupting CPU s good for locality. 2) this allows lockless access to the table-- the CPU number and queue tail counter need to be accessed together under mutual exclusion from netif_receive_skb, we assume that this is only called from device napi_poll which is non-reentrant. This patch implements RFS for TCP and connected UDP sockets. It should be usable for other flow oriented protocols. There are two configuration parameters for RFS. The "rps_flow_entries" kernel init parameter sets the number of entries in the rps_sock_flow_table, the per rxqueue sysfs entry "rps_flow_cnt" contains the number of entries in the rps_dev_flow table for the rxqueue. Both are rounded to power of two. The obvious benefit of RFS (over just RPS) is that it achieves CPU locality between the receive processing for a flow and the applications processing; this can result in increased performance (higher pps, lower latency). The benefits of RFS are dependent on cache hierarchy, application load, and other factors. On simple benchmarks, we don't necessarily see improvement and sometimes see degradation. However, for more complex benchmarks and for applications where cache pressure is much higher this technique seems to perform very well. Below are some benchmark results which show the potential benfit of this patch. The netperf test has 500 instances of netperf TCP_RR test with 1 byte req. and resp. The RPC test is an request/response test similar in structure to netperf RR test ith 100 threads on each host, but does more work in userspace that netperf. e1000e on 8 core Intel No RFS or RPS 104K tps at 30% CPU No RFS (best RPS config): 290K tps at 63% CPU RFS 303K tps at 61% CPU RPC test tps CPU% 50/90/99% usec latency Latency StdDev No RFS/RPS 103K 48% 757/900/3185 4472.35 RPS only: 174K 73% 415/993/2468 491.66 RFS 223K 73% 379/651/1382 315.61 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-16 16:01:27 -07:00
net: Allow no-cache copy from user on transmit This patch uses __copy_from_user_nocache on transmit to bypass data cache for a performance improvement. skb_add_data_nocache and skb_copy_to_page_nocache can be called by sendmsg functions to use this feature, initial support is in tcp_sendmsg. This functionality is configurable per device using ethtool. Presumably, this feature would only be useful when the driver does not touch the data. The feature is turned on by default if a device indicates that it does some form of checksum offload; it is off by default for devices that do no checksum offload or indicate no checksum is necessary. For the former case copy-checksum is probably done anyway, in the latter case the device is likely loopback in which case the no cache copy is probably not beneficial. This patch was tested using 200 instances of netperf TCP_RR with 1400 byte request and one byte reply. Platform is 16 core AMD x86. No-cache copy disabled: 672703 tps, 97.13% utilization 50/90/99% latency:244.31 484.205 1028.41 No-cache copy enabled: 702113 tps, 96.16% utilization, 50/90/99% latency 238.56 467.56 956.955 Using 14000 byte request and response sizes demonstrate the effects more dramatically: No-cache copy disabled: 79571 tps, 34.34 %utlization 50/90/95% latency 1584.46 2319.59 5001.76 No-cache copy enabled: 83856 tps, 34.81% utilization 50/90/95% latency 2508.42 2622.62 2735.88 Note especially the effect on latency tail (95th percentile). This seems to provide a nice performance improvement and is consistent in the tests I ran. Presumably, this would provide the greatest benfits in the presence of an application workload stressing the cache and a lot of transmit data happening. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-04 22:30:30 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
net: Delay default_device_exit_batch until no devices are unregistering v2 There is currently serialization network namespaces exiting and network devices exiting as the final part of netdev_run_todo does not happen under the rtnl_lock. This is compounded by the fact that the only list of devices unregistering in netdev_run_todo is local to the netdev_run_todo. This lack of serialization in extreme cases results in network devices unregistering in netdev_run_todo after the loopback device of their network namespace has been freed (making dst_ifdown unsafe), and after the their network namespace has exited (making the NETDEV_UNREGISTER, and NETDEV_UNREGISTER_FINAL callbacks unsafe). Add the missing serialization by a per network namespace count of how many network devices are unregistering and having a wait queue that is woken up whenever the count is decreased. The count and wait queue allow default_device_exit_batch to wait until all of the unregistration activity for a network namespace has finished before proceeding to unregister the loopback device and then allowing the network namespace to exit. Only a single global wait queue is used because there is a single global lock, and there is a single waiter, per network namespace wait queues would be a waste of resources. The per network namespace count of unregistering devices gives a progress guarantee because the number of network devices unregistering in an exiting network namespace must ultimately drop to zero (assuming network device unregistration completes). The basic logic remains the same as in v1. This patch is now half comment and half rtnl_lock_unregistering an expanded version of wait_event performs no extra work in the common case where no network devices are unregistering when we get to default_device_exit_batch. Reported-by: Francesco Ruggeri <fruggeri@aristanetworks.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-23 21:19:49 -07:00
net: Delay default_device_exit_batch until no devices are unregistering v2 There is currently serialization network namespaces exiting and network devices exiting as the final part of netdev_run_todo does not happen under the rtnl_lock. This is compounded by the fact that the only list of devices unregistering in netdev_run_todo is local to the netdev_run_todo. This lack of serialization in extreme cases results in network devices unregistering in netdev_run_todo after the loopback device of their network namespace has been freed (making dst_ifdown unsafe), and after the their network namespace has exited (making the NETDEV_UNREGISTER, and NETDEV_UNREGISTER_FINAL callbacks unsafe). Add the missing serialization by a per network namespace count of how many network devices are unregistering and having a wait queue that is woken up whenever the count is decreased. The count and wait queue allow default_device_exit_batch to wait until all of the unregistration activity for a network namespace has finished before proceeding to unregister the loopback device and then allowing the network namespace to exit. Only a single global wait queue is used because there is a single global lock, and there is a single waiter, per network namespace wait queues would be a waste of resources. The per network namespace count of unregistering devices gives a progress guarantee because the number of network devices unregistering in an exiting network namespace must ultimately drop to zero (assuming network device unregistration completes). The basic logic remains the same as in v1. This patch is now half comment and half rtnl_lock_unregistering an expanded version of wait_event performs no extra work in the common case where no network devices are unregistering when we get to default_device_exit_batch. Reported-by: Francesco Ruggeri <fruggeri@aristanetworks.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-23 21:19:49 -07:00
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 11:56:21 -07:00
rps: Receive Packet Steering This patch implements software receive side packet steering (RPS). RPS distributes the load of received packet processing across multiple CPUs. Problem statement: Protocol processing done in the NAPI context for received packets is serialized per device queue and becomes a bottleneck under high packet load. This substantially limits pps that can be achieved on a single queue NIC and provides no scaling with multiple cores. This solution queues packets early on in the receive path on the backlog queues of other CPUs. This allows protocol processing (e.g. IP and TCP) to be performed on packets in parallel. For each device (or each receive queue in a multi-queue device) a mask of CPUs is set to indicate the CPUs that can process packets. A CPU is selected on a per packet basis by hashing contents of the packet header (e.g. the TCP or UDP 4-tuple) and using the result to index into the CPU mask. The IPI mechanism is used to raise networking receive softirqs between CPUs. This effectively emulates in software what a multi-queue NIC can provide, but is generic requiring no device support. Many devices now provide a hash over the 4-tuple on a per packet basis (e.g. the Toeplitz hash). This patch allow drivers to set the HW reported hash in an skb field, and that value in turn is used to index into the RPS maps. Using the HW generated hash can avoid cache misses on the packet when steering it to a remote CPU. The CPU mask is set on a per device and per queue basis in the sysfs variable /sys/class/net/<device>/queues/rx-<n>/rps_cpus. This is a set of canonical bit maps for receive queues in the device (numbered by <n>). If a device does not support multi-queue, a single variable is used for the device (rx-0). Generally, we have found this technique increases pps capabilities of a single queue device with good CPU utilization. Optimal settings for the CPU mask seem to depend on architectures and cache hierarcy. Below are some results running 500 instances of netperf TCP_RR test with 1 byte req. and resp. Results show cumulative transaction rate and system CPU utilization. e1000e on 8 core Intel Without RPS: 108K tps at 33% CPU With RPS: 311K tps at 64% CPU forcedeth on 16 core AMD Without RPS: 156K tps at 15% CPU With RPS: 404K tps at 49% CPU bnx2x on 16 core AMD Without RPS 567K tps at 61% CPU (4 HW RX queues) Without RPS 738K tps at 96% CPU (8 HW RX queues) With RPS: 854K tps at 76% CPU (4 HW RX queues) Caveats: - The benefits of this patch are dependent on architecture and cache hierarchy. Tuning the masks to get best performance is probably necessary. - This patch adds overhead in the path for processing a single packet. In a lightly loaded server this overhead may eliminate the advantages of increased parallelism, and possibly cause some relative performance degradation. We have found that masks that are cache aware (share same caches with the interrupting CPU) mitigate much of this. - The RPS masks can be changed dynamically, however whenever the mask is changed this introduces the possibility of generating out of order packets. It's probably best not change the masks too frequently. Signed-off-by: Tom Herbert <therbert@google.com> include/linux/netdevice.h | 32 ++++- include/linux/skbuff.h | 3 + net/core/dev.c | 335 +++++++++++++++++++++++++++++++++++++-------- net/core/net-sysfs.c | 225 ++++++++++++++++++++++++++++++- net/core/skbuff.c | 2 + 5 files changed, 538 insertions(+), 59 deletions(-) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-16 08:03:29 +00:00