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linux/block/blk-throttle.c

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blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: move blk_throtl prototypes to block/blk.h blk_throtl interface is block internal and there's no reason to have them in linux/blkdev.h. Move them to block/blk.h. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:31:18 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: let blkcg core handle policy private data allocation Currently, blkg's are embedded in private data blkcg policy private data structure and thus allocated and freed by policies. This leads to duplicate codes in policies, hinders implementing common part in blkcg core with strong semantics, and forces duplicate blkg's for the same cgroup-q association. This patch introduces struct blkg_policy_data which is a separate data structure chained from blkg. Policies specifies the amount of private data it needs in its blkio_policy_type->pdata_size and blkcg core takes care of allocating them along with blkg which can be accessed using blkg_to_pdata(). blkg can be determined from pdata using pdata_to_blkg(). blkio_alloc_group_fn() method is accordingly updated to blkio_init_group_fn(). For consistency, tg_of_blkg() and cfqg_of_blkg() are replaced with blkg_to_tg() and blkg_to_cfqg() respectively, and functions to map in the reverse direction are added. Except that policy specific data now lives in a separate data structure from blkg, this patch doesn't introduce any functional difference. This will be used to unify blkg's for different policies. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:14 -08:00
blk-throttle: Do not use kblockd workqueue for throtl work o Dominik Klein reported a system hang issue while doing some blkio throttling testing. https://lkml.org/lkml/2011/2/24/173 o Some tracing revealed that CFQ was not dispatching any more jobs as queue unplug was not happening. And queue unplug was not happening because unplug work was not being called as there was one throttling work on same cpu which as not finished yet. And throttling work had not finished as it was tyring to dispatch a bio to CFQ but all the request descriptors were consume to it was put to sleep. o So basically it is a cyclic dependecny between CFQ unplug work and throtl dispatch work. Tejun suggested that use separate workqueue for such cases. o This patch uses a separate workqueue for throttle related work and does not rely on kblockd workqueue anymore. Cc: stable@kernel.org Reported-by: Dominik Klein <dk@in-telegence.net> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-01 13:40:54 -05:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blk-throttle: don't call xchg on bool xchg does not work portably with smaller than 32bit types. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-30 12:21:56 +02:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Add root group to td->tg_list o Currently all the dynamically allocated groups, except root grp is added to td->tg_list. This was not a problem so far but in next patch I will travel through td->tg_list to process any updates of limits on the group. If root group is not in tg_list, then root group's updates are not processed. o It is better to root group also to tg_list instead of doing special processing for it during limit updates. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:48 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blk-throttle: don't call xchg on bool xchg does not work portably with smaller than 32bit types. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-30 12:21:56 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: let blkcg core handle policy private data allocation Currently, blkg's are embedded in private data blkcg policy private data structure and thus allocated and freed by policies. This leads to duplicate codes in policies, hinders implementing common part in blkcg core with strong semantics, and forces duplicate blkg's for the same cgroup-q association. This patch introduces struct blkg_policy_data which is a separate data structure chained from blkg. Policies specifies the amount of private data it needs in its blkio_policy_type->pdata_size and blkcg core takes care of allocating them along with blkg which can be accessed using blkg_to_pdata(). blkg can be determined from pdata using pdata_to_blkg(). blkio_alloc_group_fn() method is accordingly updated to blkio_init_group_fn(). For consistency, tg_of_blkg() and cfqg_of_blkg() are replaced with blkg_to_tg() and blkg_to_cfqg() respectively, and functions to map in the reverse direction are added. Except that policy specific data now lives in a separate data structure from blkg, this patch doesn't introduce any functional difference. This will be used to unify blkg's for different policies. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:14 -08:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: let blkcg core handle policy private data allocation Currently, blkg's are embedded in private data blkcg policy private data structure and thus allocated and freed by policies. This leads to duplicate codes in policies, hinders implementing common part in blkcg core with strong semantics, and forces duplicate blkg's for the same cgroup-q association. This patch introduces struct blkg_policy_data which is a separate data structure chained from blkg. Policies specifies the amount of private data it needs in its blkio_policy_type->pdata_size and blkcg core takes care of allocating them along with blkg which can be accessed using blkg_to_pdata(). blkg can be determined from pdata using pdata_to_blkg(). blkio_alloc_group_fn() method is accordingly updated to blkio_init_group_fn(). For consistency, tg_of_blkg() and cfqg_of_blkg() are replaced with blkg_to_tg() and blkg_to_cfqg() respectively, and functions to map in the reverse direction are added. Except that policy specific data now lives in a separate data structure from blkg, this patch doesn't introduce any functional difference. This will be used to unify blkg's for different policies. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:14 -08:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: let blkcg core handle policy private data allocation Currently, blkg's are embedded in private data blkcg policy private data structure and thus allocated and freed by policies. This leads to duplicate codes in policies, hinders implementing common part in blkcg core with strong semantics, and forces duplicate blkg's for the same cgroup-q association. This patch introduces struct blkg_policy_data which is a separate data structure chained from blkg. Policies specifies the amount of private data it needs in its blkio_policy_type->pdata_size and blkcg core takes care of allocating them along with blkg which can be accessed using blkg_to_pdata(). blkg can be determined from pdata using pdata_to_blkg(). blkio_alloc_group_fn() method is accordingly updated to blkio_init_group_fn(). For consistency, tg_of_blkg() and cfqg_of_blkg() are replaced with blkg_to_tg() and blkg_to_cfqg() respectively, and functions to map in the reverse direction are added. Except that policy specific data now lives in a separate data structure from blkg, this patch doesn't introduce any functional difference. This will be used to unify blkg's for different policies. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:14 -08:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: let blkcg core handle policy private data allocation Currently, blkg's are embedded in private data blkcg policy private data structure and thus allocated and freed by policies. This leads to duplicate codes in policies, hinders implementing common part in blkcg core with strong semantics, and forces duplicate blkg's for the same cgroup-q association. This patch introduces struct blkg_policy_data which is a separate data structure chained from blkg. Policies specifies the amount of private data it needs in its blkio_policy_type->pdata_size and blkcg core takes care of allocating them along with blkg which can be accessed using blkg_to_pdata(). blkg can be determined from pdata using pdata_to_blkg(). blkio_alloc_group_fn() method is accordingly updated to blkio_init_group_fn(). For consistency, tg_of_blkg() and cfqg_of_blkg() are replaced with blkg_to_tg() and blkg_to_cfqg() respectively, and functions to map in the reverse direction are added. Except that policy specific data now lives in a separate data structure from blkg, this patch doesn't introduce any functional difference. This will be used to unify blkg's for different policies. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:14 -08:00
blkcg: add request_queue->root_blkg With per-queue policy activation, root blkg creation will be moved to blkcg core. Add q->root_blkg in preparation. For blk-throtl, this replaces throtl_data->root_tg; however, cfq needs to keep cfqd->root_group for !CONFIG_CFQ_GROUP_IOSCHED. This is to prepare for per-queue policy activation and doesn't cause any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:32 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: remove blkio_group->path[] blkio_group->path[] stores the path of the associated cgroup and is used only for debug messages. Just format the path from blkg->cgroup when printing debug messages. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:23 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Make total_nr_queued unsigned The total of two unsigned values should also be unsigned. Update throtl_log output to unsigned. Update total_nr_queued test to non-zero to be the same as the other total_nr_queued tests. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-06-13 20:19:27 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Make total_nr_queued unsigned The total of two unsigned values should also be unsigned. Update throtl_log output to unsigned. Update total_nr_queued test to non-zero to be the same as the other total_nr_queued tests. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-06-13 20:19:27 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
workqueue: deprecate system_nrt[_freezable]_wq system_nrt[_freezable]_wq are now spurious. Mark them deprecated and convert all users to system[_freezable]_wq. If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant, so there's no reason to use system_nrt[_freezable]_wq. Please use system[_freezable]_wq instead. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-By: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com>
2012-08-20 14:51:24 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
workqueue: deprecate system_nrt[_freezable]_wq system_nrt[_freezable]_wq are now spurious. Mark them deprecated and convert all users to system[_freezable]_wq. If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant, so there's no reason to use system_nrt[_freezable]_wq. Please use system[_freezable]_wq instead. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-By: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com>
2012-08-20 14:51:24 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blk-throttle: Do the new group initialization with the help of a function Group initialization code seems to be at two places. root group initialization in blk_throtl_init() and dynamically allocated group in throtl_find_alloc_tg(). Create a common function and use at both the places. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:19 -04:00
blkcg: let blkcg core handle policy private data allocation Currently, blkg's are embedded in private data blkcg policy private data structure and thus allocated and freed by policies. This leads to duplicate codes in policies, hinders implementing common part in blkcg core with strong semantics, and forces duplicate blkg's for the same cgroup-q association. This patch introduces struct blkg_policy_data which is a separate data structure chained from blkg. Policies specifies the amount of private data it needs in its blkio_policy_type->pdata_size and blkcg core takes care of allocating them along with blkg which can be accessed using blkg_to_pdata(). blkg can be determined from pdata using pdata_to_blkg(). blkio_alloc_group_fn() method is accordingly updated to blkio_init_group_fn(). For consistency, tg_of_blkg() and cfqg_of_blkg() are replaced with blkg_to_tg() and blkg_to_cfqg() respectively, and functions to map in the reverse direction are added. Except that policy specific data now lives in a separate data structure from blkg, this patch doesn't introduce any functional difference. This will be used to unify blkg's for different policies. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:14 -08:00
blkcg: tg_stats_alloc_lock is an irq lock tg_stats_alloc_lock nests inside queue lock and should always be held with irq disabled. throtl_pd_{init|exit}() were using non-irqsafe spinlock ops which triggered inverse lock ordering via irq warning via RCU freeing of blkg invoking throtl_pd_exit() w/o disabling IRQ. Update both functions to use irq safe operations. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> LKML-Reference: <1335339396.16988.80.camel@lappy> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-23 12:16:21 +02:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blk-throttle: Do the new group initialization with the help of a function Group initialization code seems to be at two places. root group initialization in blk_throtl_init() and dynamically allocated group in throtl_find_alloc_tg(). Create a common function and use at both the places. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:19 -04:00
blkcg: don't allow or retain configuration of missing devices blkcg is very peculiar in that it allows setting and remembering configurations for non-existent devices by maintaining separate data structures for configuration. This behavior is completely out of the usual norms and outright confusing; furthermore, it uses dev_t number to match the configuration to devices, which is unpredictable to begin with and becomes completely unuseable if EXT_DEVT is fully used. It is wholely unnecessary - we already have fully functional userland mechanism to program devices being hotplugged which has full access to device identification, connection topology and filesystem information. Add a new struct blkio_group_conf which contains all blkcg configurations to blkio_group and let blkio_group, which can be created iff the associated device exists and is removed when the associated device goes away, carry all configurations. Note that, after this patch, all newly created blkg's will always have the default configuration (unlimited for throttling and blkcg's weight for propio). This patch makes blkio_policy_node meaningless but doesn't remove it. The next patch will. -v2: Updated to retry after short sleep if blkg lookup/creation failed due to the queue being temporarily bypassed as indicated by -EBUSY return. Pointed out by Vivek. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:07 -08:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: tg_stats_alloc_lock is an irq lock tg_stats_alloc_lock nests inside queue lock and should always be held with irq disabled. throtl_pd_{init|exit}() were using non-irqsafe spinlock ops which triggered inverse lock ordering via irq warning via RCU freeing of blkg invoking throtl_pd_exit() w/o disabling IRQ. Update both functions to use irq safe operations. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> LKML-Reference: <1335339396.16988.80.camel@lappy> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-23 12:16:21 +02:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
workqueue: deprecate system_nrt[_freezable]_wq system_nrt[_freezable]_wq are now spurious. Mark them deprecated and convert all users to system[_freezable]_wq. If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant, so there's no reason to use system_nrt[_freezable]_wq. Please use system[_freezable]_wq instead. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-By: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com>
2012-08-20 14:51:24 -07:00
blkcg: tg_stats_alloc_lock is an irq lock tg_stats_alloc_lock nests inside queue lock and should always be held with irq disabled. throtl_pd_{init|exit}() were using non-irqsafe spinlock ops which triggered inverse lock ordering via irq warning via RCU freeing of blkg invoking throtl_pd_exit() w/o disabling IRQ. Update both functions to use irq safe operations. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> LKML-Reference: <1335339396.16988.80.camel@lappy> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-23 12:16:21 +02:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: tg_stats_alloc_lock is an irq lock tg_stats_alloc_lock nests inside queue lock and should always be held with irq disabled. throtl_pd_{init|exit}() were using non-irqsafe spinlock ops which triggered inverse lock ordering via irq warning via RCU freeing of blkg invoking throtl_pd_exit() w/o disabling IRQ. Update both functions to use irq safe operations. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> LKML-Reference: <1335339396.16988.80.camel@lappy> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-23 12:16:21 +02:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: tg_stats_alloc_lock is an irq lock tg_stats_alloc_lock nests inside queue lock and should always be held with irq disabled. throtl_pd_{init|exit}() were using non-irqsafe spinlock ops which triggered inverse lock ordering via irq warning via RCU freeing of blkg invoking throtl_pd_exit() w/o disabling IRQ. Update both functions to use irq safe operations. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> LKML-Reference: <1335339396.16988.80.camel@lappy> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-23 12:16:21 +02:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: tg_stats_alloc_lock is an irq lock tg_stats_alloc_lock nests inside queue lock and should always be held with irq disabled. throtl_pd_{init|exit}() were using non-irqsafe spinlock ops which triggered inverse lock ordering via irq warning via RCU freeing of blkg invoking throtl_pd_exit() w/o disabling IRQ. Update both functions to use irq safe operations. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> LKML-Reference: <1335339396.16988.80.camel@lappy> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-05-23 12:16:21 +02:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blk-throttle: Do the new group initialization with the help of a function Group initialization code seems to be at two places. root group initialization in blk_throtl_init() and dynamically allocated group in throtl_find_alloc_tg(). Create a common function and use at both the places. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:19 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio-throttle: Avoid calling blkiocg_lookup_group() for root group o Jeff Moyer was doing some testing on a RAM backed disk and blkiocg_lookup_group() showed up high overhead after memcpy(). Similarly somebody else reported that blkiocg_lookup_group() is eating 6% extra cpu. Though looking at the code I can't think why the overhead of this function is so high. One thing is that it is called with very high frequency (once for every IO). o For lot of folks blkio controller will be compiled in but they might not have actually created cgroups. Hence optimize the case of root cgroup where we can avoid calling blkiocg_lookup_group() if IO is happening in root group (common case). Reported-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-19 08:25:02 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: add request_queue->root_blkg With per-queue policy activation, root blkg creation will be moved to blkcg core. Add q->root_blkg in preparation. For blk-throtl, this replaces throtl_data->root_tg; however, cfq needs to keep cfqd->root_group for !CONFIG_CFQ_GROUP_IOSCHED. This is to prepare for per-queue policy activation and doesn't cause any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:32 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: unify blkg's for blkcg policies Currently, blkg is per cgroup-queue-policy combination. This is unnatural and leads to various convolutions in partially used duplicate fields in blkg, config / stat access, and general management of blkgs. This patch make blkg's per cgroup-queue and let them serve all policies. blkgs are now created and destroyed by blkcg core proper. This will allow further consolidation of common management logic into blkcg core and API with better defined semantics and layering. As a transitional step to untangle blkg management, elvswitch and policy [de]registration, all blkgs except the root blkg are being shot down during elvswitch and bypass. This patch adds blkg_root_update() to update root blkg in place on policy change. This is hacky and racy but should be good enough as interim step until we get locking simplified and switch over to proper in-place update for all blkgs. -v2: Root blkgs need to be updated on elvswitch too and blkg_alloc() comment wasn't updated according to the function change. Fixed. Both pointed out by Vivek. -v3: v2 updated blkg_destroy_all() to invoke update_root_blkg_pd() for all policies. This freed root pd during elvswitch before the last queue finished exiting and led to oops. Directly invoke update_root_blkg_pd() only on BLKIO_POLICY_PROP from cfq_exit_queue(). This also is closer to what will be done with proper in-place blkg update. Reported by Vivek. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:20 -08:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-cgroup: Allow sleeping while dynamically allocating a group Currently, all the cfq_group or throtl_group allocations happen while we are holding ->queue_lock and sleeping is not allowed. Soon, we will move to per cpu stats and also need to allocate the per group stats. As one can not call alloc_percpu() from atomic context as it can sleep, we need to drop ->queue_lock, allocate the group, retake the lock and continue processing. In throttling code, I check the queue DEAD flag again to make sure that driver did not call blk_cleanup_queue() in the mean time. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:23 -04:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blkcg: update blkg get functions take blkio_cgroup as parameter In both blkg get functions - throtl_get_tg() and cfq_get_cfqg(), instead of obtaining blkcg of %current explicitly, let the caller specify the blkcg to use as parameter and make both functions hold on to the blkcg. This is part of block cgroup interface cleanup and will help making blkcg API more modular. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:02 -08:00
blk-cgroup: Allow sleeping while dynamically allocating a group Currently, all the cfq_group or throtl_group allocations happen while we are holding ->queue_lock and sleeping is not allowed. Soon, we will move to per cpu stats and also need to allocate the per group stats. As one can not call alloc_percpu() from atomic context as it can sleep, we need to drop ->queue_lock, allocate the group, retake the lock and continue processing. In throttling code, I check the queue DEAD flag again to make sure that driver did not call blk_cleanup_queue() in the mean time. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:23 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blk-cgroup: Allow sleeping while dynamically allocating a group Currently, all the cfq_group or throtl_group allocations happen while we are holding ->queue_lock and sleeping is not allowed. Soon, we will move to per cpu stats and also need to allocate the per group stats. As one can not call alloc_percpu() from atomic context as it can sleep, we need to drop ->queue_lock, allocate the group, retake the lock and continue processing. In throttling code, I check the queue DEAD flag again to make sure that driver did not call blk_cleanup_queue() in the mean time. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:23 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: add request_queue->root_blkg With per-queue policy activation, root blkg creation will be moved to blkcg core. Add q->root_blkg in preparation. For blk-throtl, this replaces throtl_data->root_tg; however, cfq needs to keep cfqd->root_group for !CONFIG_CFQ_GROUP_IOSCHED. This is to prepare for per-queue policy activation and doesn't cause any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:32 -07:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blkcg: drop stuff unused after per-queue policy activation update * All_q_list is unused. Drop all_q_{mutex|list}. * @for_root of blkg_lookup_create() is always %false when called from outside blk-cgroup.c proper. Factor out __blkg_lookup_create() so that it doesn't check whether @q is bypassing and use the underscored version for the @for_root callsite. * blkg_destroy_all() is used only from blkcg proper and @destroy_root is always %true. Make it static and drop @destroy_root. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:34 -07:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blkcg: let blkcg core handle policy private data allocation Currently, blkg's are embedded in private data blkcg policy private data structure and thus allocated and freed by policies. This leads to duplicate codes in policies, hinders implementing common part in blkcg core with strong semantics, and forces duplicate blkg's for the same cgroup-q association. This patch introduces struct blkg_policy_data which is a separate data structure chained from blkg. Policies specifies the amount of private data it needs in its blkio_policy_type->pdata_size and blkcg core takes care of allocating them along with blkg which can be accessed using blkg_to_pdata(). blkg can be determined from pdata using pdata_to_blkg(). blkio_alloc_group_fn() method is accordingly updated to blkio_init_group_fn(). For consistency, tg_of_blkg() and cfqg_of_blkg() are replaced with blkg_to_tg() and blkg_to_cfqg() respectively, and functions to map in the reverse direction are added. Except that policy specific data now lives in a separate data structure from blkg, this patch doesn't introduce any functional difference. This will be used to unify blkg's for different policies. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:14 -08:00
block: Rename queue dead flag QUEUE_FLAG_DEAD is used to indicate that queuing new requests must stop. After this flag has been set queue draining starts. However, during the queue draining phase it is still safe to invoke the queue's request_fn, so QUEUE_FLAG_DYING is a better name for this flag. This patch has been generated by running the following command over the kernel source tree: git grep -lEw 'blk_queue_dead|QUEUE_FLAG_DEAD' | xargs sed -i.tmp -e 's/blk_queue_dead/blk_queue_dying/g' \ -e 's/QUEUE_FLAG_DEAD/QUEUE_FLAG_DYING/g'; \ sed -i.tmp -e "s/QUEUE_FLAG_DYING$(printf \\t)*5/QUEUE_FLAG_DYING$(printf \\t)5/g" \ include/linux/blkdev.h; \ sed -i.tmp -e 's/ DEAD/ DYING/g' -e 's/dead queue/a dying queue/' \ -e 's/Dead queue/A dying queue/' block/blk-core.c Signed-off-by: Bart Van Assche <bvanassche@acm.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: James Bottomley <JBottomley@Parallels.com> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: Jens Axboe <axboe@kernel.dk> Cc: Chanho Min <chanho.min@lge.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-11-28 13:42:38 +01:00
blkcg: add request_queue->root_blkg With per-queue policy activation, root blkg creation will be moved to blkcg core. Add q->root_blkg in preparation. For blk-throtl, this replaces throtl_data->root_tg; however, cfq needs to keep cfqd->root_group for !CONFIG_CFQ_GROUP_IOSCHED. This is to prepare for per-queue policy activation and doesn't cause any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:32 -07:00
blk-cgroup: Allow sleeping while dynamically allocating a group Currently, all the cfq_group or throtl_group allocations happen while we are holding ->queue_lock and sleeping is not allowed. Soon, we will move to per cpu stats and also need to allocate the per group stats. As one can not call alloc_percpu() from atomic context as it can sleep, we need to drop ->queue_lock, allocate the group, retake the lock and continue processing. In throttling code, I check the queue DEAD flag again to make sure that driver did not call blk_cleanup_queue() in the mean time. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:23 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Do not use kblockd workqueue for throtl work o Dominik Klein reported a system hang issue while doing some blkio throttling testing. https://lkml.org/lkml/2011/2/24/173 o Some tracing revealed that CFQ was not dispatching any more jobs as queue unplug was not happening. And queue unplug was not happening because unplug work was not being called as there was one throttling work on same cpu which as not finished yet. And throttling work had not finished as it was tyring to dispatch a bio to CFQ but all the request descriptors were consume to it was put to sleep. o So basically it is a cyclic dependecny between CFQ unplug work and throtl dispatch work. Tejun suggested that use separate workqueue for such cases. o This patch uses a separate workqueue for throttle related work and does not rely on kblockd workqueue anymore. Cc: stable@kernel.org Reported-by: Dominik Klein <dk@in-telegence.net> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-01 13:40:54 -05:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Do not use kblockd workqueue for throtl work o Dominik Klein reported a system hang issue while doing some blkio throttling testing. https://lkml.org/lkml/2011/2/24/173 o Some tracing revealed that CFQ was not dispatching any more jobs as queue unplug was not happening. And queue unplug was not happening because unplug work was not being called as there was one throttling work on same cpu which as not finished yet. And throttling work had not finished as it was tyring to dispatch a bio to CFQ but all the request descriptors were consume to it was put to sleep. o So basically it is a cyclic dependecny between CFQ unplug work and throtl dispatch work. Tejun suggested that use separate workqueue for such cases. o This patch uses a separate workqueue for throttle related work and does not rely on kblockd workqueue anymore. Cc: stable@kernel.org Reported-by: Dominik Klein <dk@in-telegence.net> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-01 13:40:54 -05:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Trim/adjust slice_end once a bio has been dispatched o During some testing I did following and noticed throttling stops working. - Put a very low limit on a cgroup, say 1 byte per second. - Start some reads, this will set slice_end to a very high value. - Change the limit to higher value say 1MB/s - Now IO unthrottles and finishes as expected. - Try to do the read again but IO is not limited to 1MB/s as expected. o What is happening. - Initially low value of limit sets slice_end to a very high value. - During updation of limit, slice_end is not being truncated. - Very high value of slice_end leads to keeping the existing slice valid for a very long time and new slice does not start. - tg_may_dispatch() is called in blk_throtle_bio(), and trim_slice() is not called in this path. So slice_start is some old value and practically we are able to do huge amount of IO. o There are many ways it can be fixed. I have fixed it by trying to adjust/cleanup slice_end in trim_slice(). Generally we extend slices if bio is big and can't be dispatched in one slice. After dispatch of bio, readjust the slice_end to make sure we don't end up with huge values. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-01 19:34:46 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio-throttle: Fix link failure failure on i386 o Randy Dunlap reported following linux-next failure. This patch fixes it. on i386: blk-throttle.c:(.text+0x1abb8): undefined reference to `__udivdi3' blk-throttle.c:(.text+0x1b1dc): undefined reference to `__udivdi3' o bytes_per_second interface is 64bit and I was continuing to do 64 bit division even on 32bit platform without help of special macros/functions hence the failure. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:51:14 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Trim/adjust slice_end once a bio has been dispatched o During some testing I did following and noticed throttling stops working. - Put a very low limit on a cgroup, say 1 byte per second. - Start some reads, this will set slice_end to a very high value. - Change the limit to higher value say 1MB/s - Now IO unthrottles and finishes as expected. - Try to do the read again but IO is not limited to 1MB/s as expected. o What is happening. - Initially low value of limit sets slice_end to a very high value. - During updation of limit, slice_end is not being truncated. - Very high value of slice_end leads to keeping the existing slice valid for a very long time and new slice does not start. - tg_may_dispatch() is called in blk_throtle_bio(), and trim_slice() is not called in this path. So slice_start is some old value and practically we are able to do huge amount of IO. o There are many ways it can be fixed. I have fixed it by trying to adjust/cleanup slice_end in trim_slice(). Generally we extend slices if bio is big and can't be dispatched in one slice. After dispatch of bio, readjust the slice_end to make sure we don't end up with huge values. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-01 19:34:46 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio-throttle: Fix link failure failure on i386 o Randy Dunlap reported following linux-next failure. This patch fixes it. on i386: blk-throttle.c:(.text+0x1abb8): undefined reference to `__udivdi3' blk-throttle.c:(.text+0x1b1dc): undefined reference to `__udivdi3' o bytes_per_second interface is 64bit and I was continuing to do 64 bit division even on 32bit platform without help of special macros/functions hence the failure. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:51:14 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio-throttle: Fix link failure failure on i386 o Randy Dunlap reported following linux-next failure. This patch fixes it. on i386: blk-throttle.c:(.text+0x1abb8): undefined reference to `__udivdi3' blk-throttle.c:(.text+0x1b1dc): undefined reference to `__udivdi3' o bytes_per_second interface is 64bit and I was continuing to do 64 bit division even on 32bit platform without help of special macros/functions hence the failure. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:51:14 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio-throttle: Fix possible multiplication overflow in iops calculations o User can specify max iops value of 32bit (UINT_MAX), through cgroup interface. If a user has specified say 4294967294 (UNIT_MAX - 2), then on 32bit platform, following multiplication can overflow. io_allowed = (tg->iops[rw] * jiffy_elapsed_rnd) o Explicitly cast the multiplication to 64bit and then perform division and then check whether result is still great then UNINT_MAX. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 21:16:42 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio-throttle: Fix possible multiplication overflow in iops calculations o User can specify max iops value of 32bit (UINT_MAX), through cgroup interface. If a user has specified say 4294967294 (UNIT_MAX - 2), then on 32bit platform, following multiplication can overflow. io_allowed = (tg->iops[rw] * jiffy_elapsed_rnd) o Explicitly cast the multiplication to 64bit and then perform division and then check whether result is still great then UNINT_MAX. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 21:16:42 +02:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio-throttle: Fix link failure failure on i386 o Randy Dunlap reported following linux-next failure. This patch fixes it. on i386: blk-throttle.c:(.text+0x1abb8): undefined reference to `__udivdi3' blk-throttle.c:(.text+0x1b1dc): undefined reference to `__udivdi3' o bytes_per_second interface is 64bit and I was continuing to do 64 bit division even on 32bit platform without help of special macros/functions hence the failure. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:51:14 +02:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio-throttle: There is no need to convert jiffies to milli seconds o Do not convert jiffies to mili seconds as it is not required. Just work with jiffies and HZ. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 21:16:38 +02:00
blkio-throttle: Fix link failure failure on i386 o Randy Dunlap reported following linux-next failure. This patch fixes it. on i386: blk-throttle.c:(.text+0x1abb8): undefined reference to `__udivdi3' blk-throttle.c:(.text+0x1b1dc): undefined reference to `__udivdi3' o bytes_per_second interface is 64bit and I was continuing to do 64 bit division even on 32bit platform without help of special macros/functions hence the failure. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:51:14 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Make no throttling rule group processing lockless Currently we take a queue lock on each bio to check if there are any throttling rules associated with the group and also update the stats. Now access the group under rcu and update the stats without taking the queue lock. Queue lock is taken only if there are throttling rules associated with the group. So the common case of root group when there are no rules, save unnecessary pounding of request queue lock. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:31 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: move statistics update code to policies As with conf/stats file handling code, there's no reason for stat update code to live in blkcg core with policies calling into update them. The current organization is both inflexible and complex. This patch moves stat update code to specific policies. All blkiocg_update_*_stats() functions which deal with BLKIO_POLICY_PROP stats are collapsed into their cfq_blkiocg_update_*_stats() counterparts. blkiocg_update_dispatch_stats() is used by both policies and duplicated as throtl_update_dispatch_stats() and cfq_blkiocg_update_dispatch_stats(). This will be cleaned up later. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move statistics update code to policies As with conf/stats file handling code, there's no reason for stat update code to live in blkcg core with policies calling into update them. The current organization is both inflexible and complex. This patch moves stat update code to specific policies. All blkiocg_update_*_stats() functions which deal with BLKIO_POLICY_PROP stats are collapsed into their cfq_blkiocg_update_*_stats() counterparts. blkiocg_update_dispatch_stats() is used by both policies and duplicated as throtl_update_dispatch_stats() and cfq_blkiocg_update_dispatch_stats(). This will be cleaned up later. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move statistics update code to policies As with conf/stats file handling code, there's no reason for stat update code to live in blkcg core with policies calling into update them. The current organization is both inflexible and complex. This patch moves stat update code to specific policies. All blkiocg_update_*_stats() functions which deal with BLKIO_POLICY_PROP stats are collapsed into their cfq_blkiocg_update_*_stats() counterparts. blkiocg_update_dispatch_stats() is used by both policies and duplicated as throtl_update_dispatch_stats() and cfq_blkiocg_update_dispatch_stats(). This will be cleaned up later. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move statistics update code to policies As with conf/stats file handling code, there's no reason for stat update code to live in blkcg core with policies calling into update them. The current organization is both inflexible and complex. This patch moves stat update code to specific policies. All blkiocg_update_*_stats() functions which deal with BLKIO_POLICY_PROP stats are collapsed into their cfq_blkiocg_update_*_stats() counterparts. blkiocg_update_dispatch_stats() is used by both policies and duplicated as throtl_update_dispatch_stats() and cfq_blkiocg_update_dispatch_stats(). This will be cleaned up later. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move statistics update code to policies As with conf/stats file handling code, there's no reason for stat update code to live in blkcg core with policies calling into update them. The current organization is both inflexible and complex. This patch moves stat update code to specific policies. All blkiocg_update_*_stats() functions which deal with BLKIO_POLICY_PROP stats are collapsed into their cfq_blkiocg_update_*_stats() counterparts. blkiocg_update_dispatch_stats() is used by both policies and duplicated as throtl_update_dispatch_stats() and cfq_blkiocg_update_dispatch_stats(). This will be cleaned up later. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move refcnt to blkcg core Currently, blkcg policy implementations manage blkg refcnt duplicating mostly identical code in both policies. This patch moves refcnt to blkg and let blkcg core handle refcnt and freeing of blkgs. * cfq blkgs now also get freed via RCU. * cfq blkgs lose RB_EMPTY_ROOT() sanity check on blkg free. If necessary, we can add blkio_exit_group_fn() to resurrect this. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:15 -08:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move refcnt to blkcg core Currently, blkcg policy implementations manage blkg refcnt duplicating mostly identical code in both policies. This patch moves refcnt to blkg and let blkcg core handle refcnt and freeing of blkgs. * cfq blkgs now also get freed via RCU. * cfq blkgs lose RB_EMPTY_ROOT() sanity check on blkg free. If necessary, we can add blkio_exit_group_fn() to resurrect this. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:15 -08:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Fix calculation of max number of WRITES to be dispatched o Currently we try to dispatch more READS and less WRITES (75%, 25%) in one dispatch round. ummy pointed out that there is a bug in max_nr_writes calculation. This patch fixes it. Reported-by: ummy y <yummylln@yahoo.com.cn> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-15 19:32:42 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blkcg: move per-queue blkg list heads and counters to queue and blkg Currently, specific policy implementations are responsible for maintaining list and number of blkgs. This duplicates code unnecessarily, and hinders factoring common code and providing blkcg API with better defined semantics. After this patch, request_queue hosts list heads and counters and blkg has list nodes for both policies. This patch only relocates the necessary fields and the next patch will actually move management code into blkcg core. Note that request_queue->blkg_list[] and ->nr_blkgs[] are hardcoded to have 2 elements. This is to avoid include dependency and will be removed by the next patch. This patch doesn't introduce any behavior change. -v2: Now unnecessary conditional on CONFIG_BLK_CGROUP_MODULE removed as pointed out by Vivek. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:18 -08:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blkcg: unify blkg's for blkcg policies Currently, blkg is per cgroup-queue-policy combination. This is unnatural and leads to various convolutions in partially used duplicate fields in blkg, config / stat access, and general management of blkgs. This patch make blkg's per cgroup-queue and let them serve all policies. blkgs are now created and destroyed by blkcg core proper. This will allow further consolidation of common management logic into blkcg core and API with better defined semantics and layering. As a transitional step to untangle blkg management, elvswitch and policy [de]registration, all blkgs except the root blkg are being shot down during elvswitch and bypass. This patch adds blkg_root_update() to update root blkg in place on policy change. This is hacky and racy but should be good enough as interim step until we get locking simplified and switch over to proper in-place update for all blkgs. -v2: Root blkgs need to be updated on elvswitch too and blkg_alloc() comment wasn't updated according to the function change. Fixed. Both pointed out by Vivek. -v3: v2 updated blkg_destroy_all() to invoke update_root_blkg_pd() for all policies. This freed root pd during elvswitch before the last queue finished exiting and led to oops. Directly invoke update_root_blkg_pd() only on BLKIO_POLICY_PROP from cfq_exit_queue(). This also is closer to what will be done with proper in-place blkg update. Reported by Vivek. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:20 -08:00
blkcg: move per-queue blkg list heads and counters to queue and blkg Currently, specific policy implementations are responsible for maintaining list and number of blkgs. This duplicates code unnecessarily, and hinders factoring common code and providing blkcg API with better defined semantics. After this patch, request_queue hosts list heads and counters and blkg has list nodes for both policies. This patch only relocates the necessary fields and the next patch will actually move management code into blkcg core. Note that request_queue->blkg_list[] and ->nr_blkgs[] are hardcoded to have 2 elements. This is to avoid include dependency and will be removed by the next patch. This patch doesn't introduce any behavior change. -v2: Now unnecessary conditional on CONFIG_BLK_CGROUP_MODULE removed as pointed out by Vivek. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:18 -08:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blk-throttle: Reset group slice when limits are changed Lina reported that if throttle limits are initially very high and then dropped, then no new bio might be dispatched for a long time. And the reason being that after dropping the limits we don't reset the existing slice and do the rate calculation with new low rate and account the bios dispatched at high rate. To fix it, reset the slice upon rate change. https://lkml.org/lkml/2011/3/10/298 Another problem with very high limit is that we never queued the bio on throtl service tree. That means we kept on extending the group slice but never trimmed it. Fix that also by regulary trimming the slice even if bio is not being queued up. Reported-by: Lina Lu <lulina_nuaa@foxmail.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-22 21:54:29 +01:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Use blk_plug in throttle dispatch Use plug in throttle dispatch also as we are dispatching a bunch of bios in throttle context and some of them might merge. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-09 08:27:37 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Recalculate the throttled bio dispatch time upon throttle limit change o Currently any cgroup throttle limit changes are processed asynchronousy and the change does not take affect till a new bio is dispatched from same group. o It might happen that a user sets a redicuously low limit on throttling. Say 1 bytes per second on reads. In such cases simple operations like mount a disk can wait for a very long time. o Once bio is throttled, there is no easy way to come out of that wait even if user increases the read limit later. o This patch fixes it. Now if a user changes the cgroup limits, we recalculate the bio dispatch time according to new limits. o Can't take queueu lock under blkcg_lock, hence after the change I wake up the dispatch thread again which recalculates the time. So there are some variables being synchronized across two threads without lock and I had to make use of barriers. Hoping I have used barriers correctly. Any review of memory barrier code especially will help. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:49 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Make total_nr_queued unsigned The total of two unsigned values should also be unsigned. Update throtl_log output to unsigned. Update total_nr_queued test to non-zero to be the same as the other total_nr_queued tests. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-06-13 20:19:27 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Use blk_plug in throttle dispatch Use plug in throttle dispatch also as we are dispatching a bunch of bios in throttle context and some of them might merge. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-09 08:27:37 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Use blk_plug in throttle dispatch Use plug in throttle dispatch also as we are dispatching a bunch of bios in throttle context and some of them might merge. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-09 08:27:37 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Do not use kblockd workqueue for throtl work o Dominik Klein reported a system hang issue while doing some blkio throttling testing. https://lkml.org/lkml/2011/2/24/173 o Some tracing revealed that CFQ was not dispatching any more jobs as queue unplug was not happening. And queue unplug was not happening because unplug work was not being called as there was one throttling work on same cpu which as not finished yet. And throttling work had not finished as it was tyring to dispatch a bio to CFQ but all the request descriptors were consume to it was put to sleep. o So basically it is a cyclic dependecny between CFQ unplug work and throtl dispatch work. Tejun suggested that use separate workqueue for such cases. o This patch uses a separate workqueue for throttle related work and does not rely on kblockd workqueue anymore. Cc: stable@kernel.org Reported-by: Dominik Klein <dk@in-telegence.net> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-01 13:40:54 -05:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Reset group slice when limits are changed Lina reported that if throttle limits are initially very high and then dropped, then no new bio might be dispatched for a long time. And the reason being that after dropping the limits we don't reset the existing slice and do the rate calculation with new low rate and account the bios dispatched at high rate. To fix it, reset the slice upon rate change. https://lkml.org/lkml/2011/3/10/298 Another problem with very high limit is that we never queued the bio on throtl service tree. That means we kept on extending the group slice but never trimmed it. Fix that also by regulary trimming the slice even if bio is not being queued up. Reported-by: Lina Lu <lulina_nuaa@foxmail.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-22 21:54:29 +01:00
blk-throttle: Make total_nr_queued unsigned The total of two unsigned values should also be unsigned. Update throtl_log output to unsigned. Update total_nr_queued test to non-zero to be the same as the other total_nr_queued tests. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-06-13 20:19:27 +02:00
workqueue: use mod_delayed_work() instead of __cancel + queue Now that mod_delayed_work() is safe to call from IRQ handlers, __cancel_delayed_work() followed by queue_delayed_work() can be replaced with mod_delayed_work(). Most conversions are straight-forward except for the following. * net/core/link_watch.c: linkwatch_schedule_work() was doing a quite elaborate dancing around its delayed_work. Collapse it such that linkwatch_work is queued for immediate execution if LW_URGENT and existing timer is kept otherwise. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
2012-08-21 13:18:24 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: drop BLKCG_STAT_{PRIV|POL|OFF} macros Now that all stat handling code lives in policy implementations, there's no need to encode policy ID in cft->private. * Export blkcg_prfill_[rw]stat() from blkcg, remove blkcg_print_[rw]stat(), and implement cfqg_print_[rw]stat() which use hard-code BLKIO_POLICY_PROP. * Use cft->private for offset of the target field directly and drop BLKCG_STAT_{PRIV|POL|OFF}(). Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:45 -07:00
blkcg: cfq doesn't need per-cpu dispatch stats blkio_group_stats_cpu is used to count dispatch stats using per-cpu counters. This is used by both blk-throtl and cfq-iosched but the sharing is rather silly. * cfq-iosched doesn't need per-cpu dispatch stats. cfq always updates those stats while holding queue_lock. * blk-throtl needs per-cpu dispatch stats but only service_bytes and serviced. It doesn't make use of sectors. This patch makes cfq add and use global stats for service_bytes, serviced and sectors, removes per-cpu sectors counter and moves per-cpu stat printing code to blk-throttle.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: embed struct blkg_policy_data in policy specific data Currently blkg_policy_data carries policy specific data as char flex array instead of being embedded in policy specific data. This was forced by oddities around blkg allocation which are all gone now. This patch makes blkg_policy_data embedded in policy specific data - throtl_grp and cfq_group so that it's more conventional and consistent with how io_cq is handled. * blkcg_policy->pdata_size is renamed to ->pd_size. * Functions which used to take void *pdata now takes struct blkg_policy_data *pd. * blkg_to_pdata/pdata_to_blkg() updated to blkg_to_pd/pd_to_blkg(). * Dummy struct blkg_policy_data definition added. Dummy pdata_to_blkg() definition was unused and inconsistent with the non-dummy version - correct dummy pd_to_blkg() added. * throtl and cfq updated accordingly. * As dummy blkg_to_pd/pd_to_blkg() are provided, blkg_to_cfqg/cfqg_to_blkg() don't need to be ifdef'd. Moved outside ifdef block. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:26 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: move blkio_group_conf->iops and ->bps to blk-throttle blkio_cgroup_conf->iops and ->bps are owned by blk-throttle and has no reason to be defined in blkcg core. Drop them and let conf setting functions directly manipulate throtl_grp->bps[] and ->iops[]. This makes blkio_group_conf empty. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: drop BLKCG_STAT_{PRIV|POL|OFF} macros Now that all stat handling code lives in policy implementations, there's no need to encode policy ID in cft->private. * Export blkcg_prfill_[rw]stat() from blkcg, remove blkcg_print_[rw]stat(), and implement cfqg_print_[rw]stat() which use hard-code BLKIO_POLICY_PROP. * Use cft->private for offset of the target field directly and drop BLKCG_STAT_{PRIV|POL|OFF}(). Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:45 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
blkcg: drop BLKCG_STAT_{PRIV|POL|OFF} macros Now that all stat handling code lives in policy implementations, there's no need to encode policy ID in cft->private. * Export blkcg_prfill_[rw]stat() from blkcg, remove blkcg_print_[rw]stat(), and implement cfqg_print_[rw]stat() which use hard-code BLKIO_POLICY_PROP. * Use cft->private for offset of the target field directly and drop BLKCG_STAT_{PRIV|POL|OFF}(). Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:45 -07:00
blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c blkio_group_stats_cpu is used only by blk-throtl and has no reason to be defined in blkcg core. * Move blkio_group_stats_cpu to blk-throttle.c and rename it to tg_stats_cpu. * blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu. prfill functions updated accordingly. * All related macros / functions are renamed so that they have tg_ prefix and the unnecessary @pol arguments are dropped. * Per-cpu stats allocation code is also moved from blk-cgroup.c to blk-throttle.c and gets simplified to only deal with BLKIO_POLICY_THROTL. percpu stat free is performed by the exit method throtl_exit_blkio_group(). * throtl_reset_group_stats() implemented for blkio_reset_group_stats_fn method so that tg->stats_cpu can be reset. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move conf/stat file handling code to policies blkcg conf/stat handling is convoluted in that details which belong to specific policy implementations are all out in blkcg core and then policies hook into core layer to access and manipulate confs and stats. This sadly achieves both inflexibility (confs/stats can't be modified without messing with blkcg core) and complexity (all the call-ins and call-backs). The previous patches restructured conf and stat handling code such that they can be separated out. This patch relocates the file handling part. All conf/stat file handling code which belongs to BLKIO_POLICY_PROP is moved to cfq-iosched.c and all BKLIO_POLICY_THROTL code to blk-throtl.c. The move is verbatim except for blkio_update_group_{weight|bps|iops}() callbacks which relays conf changes to policies. The configuration settings are handled in policies themselves so the relaying isn't necessary. Conf setting functions are modified to directly call per-policy update functions and the relaying mechanism is dropped. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
block: Move blk_throtl_exit() call to blk_cleanup_queue() Move blk_throtl_exit() in blk_cleanup_queue() as blk_throtl_exit() is written in such a way that it needs queue lock. In blk_release_queue() there is no gurantee that ->queue_lock is still around. Initially blk_throtl_exit() was in blk_cleanup_queue() but Ingo reported one problem. https://lkml.org/lkml/2010/10/23/86 And a quick fix moved blk_throtl_exit() to blk_release_queue(). commit 7ad58c028652753814054f4e3ac58f925e7343f4 Author: Jens Axboe <jaxboe@fusionio.com> Date: Sat Oct 23 20:40:26 2010 +0200 block: fix use-after-free bug in blk throttle code This patch reverts above change and does not try to shutdown the throtl work in blk_sync_queue(). By avoiding call to throtl_shutdown_timer_wq() from blk_sync_queue(), we should also avoid the problem reported by Ingo. blk_sync_queue() seems to be used only by md driver and it seems to be using it to make sure q->unplug_fn is not called as md registers its own unplug functions and it is about to free up the data structures used by unplug_fn(). Block throttle does not call back into unplug_fn() or into md. So there is no need to cancel blk throttle work. In fact I think cancelling block throttle work is bad because it might happen that some bios are throttled and scheduled to be dispatched later with the help of pending work and if work is cancelled, these bios might never be dispatched. Block layer also uses blk_sync_queue() during blk_cleanup_queue() and blk_release_queue() time. That should be safe as we are also calling blk_throtl_exit() which should make sure all the throttling related data structures are cleaned up. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-02 19:05:33 -05:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: collapse blkcg_policy_ops into blkcg_policy There's no reason to keep blkcg_policy_ops separate. Collapse it into blkcg_policy. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:27 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Make no throttling rule group processing lockless Currently we take a queue lock on each bio to check if there are any throttling rules associated with the group and also update the stats. Now access the group under rcu and update the stats without taking the queue lock. Queue lock is taken only if there are throttling rules associated with the group. So the common case of root group when there are no rules, save unnecessary pounding of request queue lock. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:31 -04:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blk-throttle: Make no throttling rule group processing lockless Currently we take a queue lock on each bio to check if there are any throttling rules associated with the group and also update the stats. Now access the group under rcu and update the stats without taking the queue lock. Queue lock is taken only if there are throttling rules associated with the group. So the common case of root group when there are no rules, save unnecessary pounding of request queue lock. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:31 -04:00
blkcg: move statistics update code to policies As with conf/stats file handling code, there's no reason for stat update code to live in blkcg core with policies calling into update them. The current organization is both inflexible and complex. This patch moves stat update code to specific policies. All blkiocg_update_*_stats() functions which deal with BLKIO_POLICY_PROP stats are collapsed into their cfq_blkiocg_update_*_stats() counterparts. blkiocg_update_dispatch_stats() is used by both policies and duplicated as throtl_update_dispatch_stats() and cfq_blkiocg_update_dispatch_stats(). This will be cleaned up later. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:44 -07:00
blkcg: move rcu_read_lock() outside of blkio_group get functions rcu_read_lock() in throtl_get_tb() and cfq_get_cfqg() holds onto @blkcg while looking up blkg. For API cleanup, the next patch will make the caller responsible for determining @blkcg to look blkg from and let them specify it as a parameter. Move rcu read locking out to the callers to prepare for the change. -v2: Originally this patch was described as a fix for RCU read locking bug around @blkg, which Vivek pointed out to be incorrect. It was from misunderstanding the role of rcu locking as protecting @blkg not @blkcg. Patch description updated. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:01 -08:00
blk-throttle: Make no throttling rule group processing lockless Currently we take a queue lock on each bio to check if there are any throttling rules associated with the group and also update the stats. Now access the group under rcu and update the stats without taking the queue lock. Queue lock is taken only if there are throttling rules associated with the group. So the common case of root group when there are no rules, save unnecessary pounding of request queue lock. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:31 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blk-cgroup: Allow sleeping while dynamically allocating a group Currently, all the cfq_group or throtl_group allocations happen while we are holding ->queue_lock and sleeping is not allowed. Soon, we will move to per cpu stats and also need to allocate the per group stats. As one can not call alloc_percpu() from atomic context as it can sleep, we need to drop ->queue_lock, allocate the group, retake the lock and continue processing. In throttling code, I check the queue DEAD flag again to make sure that driver did not call blk_cleanup_queue() in the mean time. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:23 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: process limit change only through one function With the help of cgroup interface one can go and upate the bps/iops limits of existing group. Once the limits are udpated, a thread is woken up to see if some blocked group needs recalculation based on new limits and needs to be requeued. There was also a piece of code where I was checking for group limit update when a fresh bio comes in. This patch gets rid of that piece of code and keeps processing the limit change at one place throtl_process_limit_change(). It just keeps the code simple and easy to understand. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:05:14 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Reset group slice when limits are changed Lina reported that if throttle limits are initially very high and then dropped, then no new bio might be dispatched for a long time. And the reason being that after dropping the limits we don't reset the existing slice and do the rate calculation with new low rate and account the bios dispatched at high rate. To fix it, reset the slice upon rate change. https://lkml.org/lkml/2011/3/10/298 Another problem with very high limit is that we never queued the bio on throtl service tree. That means we kept on extending the group slice but never trimmed it. Fix that also by regulary trimming the slice even if bio is not being queued up. Reported-by: Lina Lu <lulina_nuaa@foxmail.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-22 21:54:29 +01:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: Add __attribute__((format(printf...) and fix fallout Use the compiler to verify format strings and arguments. Fix fallout. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-06-13 10:42:49 +02:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkio: Implementation of IOPS limit logic o core logic of implementing IOPS throttling. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:37 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: make blk-throttle preserve the issuing task on delayed bios Make blk-throttle call bio_associate_current() on bios being delayed such that they get issued to block layer with the original io_context. This allows stacking blk-throttle and cfq-iosched propio policies. bios will always be issued with the correct ioc and blkcg whether it gets delayed by blk-throttle or not. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:29 -08:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: move rcu_read_lock() outside of blkio_group get functions rcu_read_lock() in throtl_get_tb() and cfq_get_cfqg() holds onto @blkcg while looking up blkg. For API cleanup, the next patch will make the caller responsible for determining @blkcg to look blkg from and let them specify it as a parameter. Move rcu read locking out to the callers to prepare for the change. -v2: Originally this patch was described as a fix for RCU read locking bug around @blkg, which Vivek pointed out to be incorrect. It was from misunderstanding the role of rcu locking as protecting @blkg not @blkcg. Patch description updated. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:01 -08:00
block: reorganize throtl_get_tg() and blk_throtl_bio() blk_throtl_bio() and throtl_get_tg() have rather unusual interface. * throtl_get_tg() returns pointer to a valid tg or ERR_PTR(-ENODEV), and drops queue_lock in the latter case. Different locking context depending on return value is error-prone and DEAD state is scheduled to be protected by queue_lock anyway. Move DEAD check inside queue_lock and return valid tg or NULL. * blk_throtl_bio() indicates return status both with its return value and in/out param **@bio. The former is used to indicate whether queue is found to be dead during throtl processing. The latter whether the bio is throttled. There's no point in returning DEAD check result from blk_throtl_bio(). The queue can die after blk_throtl_bio() is finished but before make_request_fn() grabs queue lock. Make it take *@bio instead and return boolean result indicating whether the request is throttled or not. This patch doesn't cause any visible functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:33:01 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
block: fix request_queue lifetime handling by making blk_queue_cleanup() properly shutdown request_queue is refcounted but actually depdends on lifetime management from the queue owner - on blk_cleanup_queue(), block layer expects that there's no request passing through request_queue and no new one will. This is fundamentally broken. The queue owner (e.g. SCSI layer) doesn't have a way to know whether there are other active users before calling blk_cleanup_queue() and other users (e.g. bsg) don't have any guarantee that the queue is and would stay valid while it's holding a reference. With delay added in blk_queue_bio() before queue_lock is grabbed, the following oops can be easily triggered when a device is removed with in-flight IOs. sd 0:0:1:0: [sdb] Stopping disk ata1.01: disabled general protection fault: 0000 [#1] PREEMPT SMP CPU 2 Modules linked in: Pid: 648, comm: test_rawio Not tainted 3.1.0-rc3-work+ #56 Bochs Bochs RIP: 0010:[<ffffffff8137d651>] [<ffffffff8137d651>] elv_rqhash_find+0x61/0x100 ... Process test_rawio (pid: 648, threadinfo ffff880019efa000, task ffff880019ef8a80) ... Call Trace: [<ffffffff8137d774>] elv_merge+0x84/0xe0 [<ffffffff81385b54>] blk_queue_bio+0xf4/0x400 [<ffffffff813838ea>] generic_make_request+0xca/0x100 [<ffffffff81383994>] submit_bio+0x74/0x100 [<ffffffff811c53ec>] dio_bio_submit+0xbc/0xc0 [<ffffffff811c610e>] __blockdev_direct_IO+0x92e/0xb40 [<ffffffff811c39f7>] blkdev_direct_IO+0x57/0x60 [<ffffffff8113b1c5>] generic_file_aio_read+0x6d5/0x760 [<ffffffff8118c1ca>] do_sync_read+0xda/0x120 [<ffffffff8118ce55>] vfs_read+0xc5/0x180 [<ffffffff8118cfaa>] sys_pread64+0x9a/0xb0 [<ffffffff81afaf6b>] system_call_fastpath+0x16/0x1b This happens because blk_queue_cleanup() destroys the queue and elevator whether IOs are in progress or not and DEAD tests are sprinkled in the request processing path without proper synchronization. Similar problem exists for blk-throtl. On queue cleanup, blk-throtl is shutdown whether it has requests in it or not. Depending on timing, it either oopses or throttled bios are lost putting tasks which are waiting for bio completion into eternal D state. The way it should work is having the usual clear distinction between shutdown and release. Shutdown drains all currently pending requests, marks the queue dead, and performs partial teardown of the now unnecessary part of the queue. Even after shutdown is complete, reference holders are still allowed to issue requests to the queue although they will be immmediately failed. The rest of teardown happens on release. This patch makes the following changes to make blk_queue_cleanup() behave as proper shutdown. * QUEUE_FLAG_DEAD is now set while holding both q->exit_mutex and queue_lock. * Unsynchronized DEAD check in generic_make_request_checks() removed. This couldn't make any meaningful difference as the queue could die after the check. * blk_drain_queue() updated such that it can drain all requests and is now called during cleanup. * blk_throtl updated such that it checks DEAD on grabbing queue_lock, drains all throttled bios during cleanup and free td when queue is released. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:42:16 +02:00
block: use lockdep_assert_held for queue locking Instead of an ugly open coded variant. Cc: axboe@kernel.dk Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-30 12:33:28 +02:00
block: fix request_queue lifetime handling by making blk_queue_cleanup() properly shutdown request_queue is refcounted but actually depdends on lifetime management from the queue owner - on blk_cleanup_queue(), block layer expects that there's no request passing through request_queue and no new one will. This is fundamentally broken. The queue owner (e.g. SCSI layer) doesn't have a way to know whether there are other active users before calling blk_cleanup_queue() and other users (e.g. bsg) don't have any guarantee that the queue is and would stay valid while it's holding a reference. With delay added in blk_queue_bio() before queue_lock is grabbed, the following oops can be easily triggered when a device is removed with in-flight IOs. sd 0:0:1:0: [sdb] Stopping disk ata1.01: disabled general protection fault: 0000 [#1] PREEMPT SMP CPU 2 Modules linked in: Pid: 648, comm: test_rawio Not tainted 3.1.0-rc3-work+ #56 Bochs Bochs RIP: 0010:[<ffffffff8137d651>] [<ffffffff8137d651>] elv_rqhash_find+0x61/0x100 ... Process test_rawio (pid: 648, threadinfo ffff880019efa000, task ffff880019ef8a80) ... Call Trace: [<ffffffff8137d774>] elv_merge+0x84/0xe0 [<ffffffff81385b54>] blk_queue_bio+0xf4/0x400 [<ffffffff813838ea>] generic_make_request+0xca/0x100 [<ffffffff81383994>] submit_bio+0x74/0x100 [<ffffffff811c53ec>] dio_bio_submit+0xbc/0xc0 [<ffffffff811c610e>] __blockdev_direct_IO+0x92e/0xb40 [<ffffffff811c39f7>] blkdev_direct_IO+0x57/0x60 [<ffffffff8113b1c5>] generic_file_aio_read+0x6d5/0x760 [<ffffffff8118c1ca>] do_sync_read+0xda/0x120 [<ffffffff8118ce55>] vfs_read+0xc5/0x180 [<ffffffff8118cfaa>] sys_pread64+0x9a/0xb0 [<ffffffff81afaf6b>] system_call_fastpath+0x16/0x1b This happens because blk_queue_cleanup() destroys the queue and elevator whether IOs are in progress or not and DEAD tests are sprinkled in the request processing path without proper synchronization. Similar problem exists for blk-throtl. On queue cleanup, blk-throtl is shutdown whether it has requests in it or not. Depending on timing, it either oopses or throttled bios are lost putting tasks which are waiting for bio completion into eternal D state. The way it should work is having the usual clear distinction between shutdown and release. Shutdown drains all currently pending requests, marks the queue dead, and performs partial teardown of the now unnecessary part of the queue. Even after shutdown is complete, reference holders are still allowed to issue requests to the queue although they will be immmediately failed. The rest of teardown happens on release. This patch makes the following changes to make blk_queue_cleanup() behave as proper shutdown. * QUEUE_FLAG_DEAD is now set while holding both q->exit_mutex and queue_lock. * Unsynchronized DEAD check in generic_make_request_checks() removed. This couldn't make any meaningful difference as the queue could die after the check. * blk_drain_queue() updated such that it can drain all requests and is now called during cleanup. * blk_throtl updated such that it checks DEAD on grabbing queue_lock, drains all throttled bios during cleanup and free td when queue is released. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:42:16 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Some cleanups and race fixes in limit update code When throttle group limits are updated through cgroups, a thread is woken up to process these updates. While reviewing that code, oleg noted couple of race conditions existed in the code and he also suggested that code can be simplified. This patch fixes the races simplifies the code based on Oleg's suggestions: - Use xchg(). - Introduced a common function throtl_update_blkio_group_common() which is shared now by all iops/bps update functions. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Fixed a merge issue, throtl_schedule_delayed_work() takes throtl_data as the argument now, not the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-07 21:09:32 +01:00
blk-throttle: Do the new group initialization with the help of a function Group initialization code seems to be at two places. root group initialization in blk_throtl_init() and dynamically allocated group in throtl_find_alloc_tg(). Create a common function and use at both the places. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:19 -04:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: factor out blkio_group creation Currently both blk-throttle and cfq-iosched implement their own blkio_group creation code in throtl_get_tg() and cfq_get_cfqg(). This patch factors out the common code into blkg_lookup_create(), which returns ERR_PTR value so that transitional failures due to queue bypass can be distinguished from other failures. * New plkio_policy_ops methods blkio_alloc_group_fn() and blkio_link_group_fn added. Both are transitional and will be removed once the blkg management code is fully moved into blk-cgroup.c. * blkio_alloc_group_fn() allocates policy-specific blkg which is usually a larger data structure with blkg as the first entry and intiailizes it. Note that initialization of blkg proper, including percpu stats, is responsibility of blk-cgroup proper. Note that default config (weight, bps...) initialization is done from this method; otherwise, we end up violating locking order between blkcg and q locks via blkcg_get_CONF() functions. * blkio_link_group_fn() is called under queue_lock and responsible for linking the blkg to the queue. blkcg side is handled by blk-cgroup proper. * The common blkg creation function is named blkg_lookup_create() and blkiocg_lookup_group() is renamed to blkg_lookup() for consistency. Also, throtl / cfq related functions are similarly [re]named for consistency. This simplifies blkcg policy implementations and enables further cleanup. -v2: Vivek noticed that blkg_lookup_create() incorrectly tested blk_queue_dead() instead of blk_queue_bypass() leading a user of the function ending up creating a new blkg on bypassing queue. This is a bug introduced while relocating bypass patches before this one. Fixed. -v3: ERR_PTR patch folded into this one. @for_root added to blkg_lookup_create() to allow creating root group on a bypassed queue during elevator switch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:06 -08:00
blk-throttle: Dynamically allocate root group Currently, we allocate root throtl_grp statically. But as we will be introducing per cpu stat pointers and that will be allocated dynamically even for root group, we might as well make whole root throtl_grp allocation dynamic and treat it in same manner as other groups. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:24 -04:00
blkio: Add root group to td->tg_list o Currently all the dynamically allocated groups, except root grp is added to td->tg_list. This was not a problem so far but in next patch I will travel through td->tg_list to process any updates of limits on the group. If root group is not in tg_list, then root group's updates are not processed. o It is better to root group also to tg_list instead of doing special processing for it during limit updates. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-01 14:49:48 +02:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blk-throttle: Dynamically allocate root group Currently, we allocate root throtl_grp statically. But as we will be introducing per cpu stat pointers and that will be allocated dynamically even for root group, we might as well make whole root throtl_grp allocation dynamic and treat it in same manner as other groups. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-19 15:38:24 -04:00
blkcg: implement per-queue policy activation All blkcg policies were assumed to be enabled on all request_queues. Due to various implementation obstacles, during the recent blkcg core updates, this was temporarily implemented as shooting down all !root blkgs on elevator switch and policy [de]registration combined with half-broken in-place root blkg updates. In addition to being buggy and racy, this meant losing all blkcg configurations across those events. Now that blkcg is cleaned up enough, this patch replaces the temporary implementation with proper per-queue policy activation. Each blkcg policy should call the new blkcg_[de]activate_policy() to enable and disable the policy on a specific queue. blkcg_activate_policy() allocates and installs policy data for the policy for all existing blkgs. blkcg_deactivate_policy() does the reverse. If a policy is not enabled for a given queue, blkg printing / config functions skip the respective blkg for the queue. blkcg_activate_policy() also takes care of root blkg creation, and cfq_init_queue() and blk_throtl_init() are updated accordingly. This replaces blkcg_bypass_{start|end}() and update_root_blkg_pd() unnecessary. Dropped. v2: cfq_init_queue() was returning uninitialized @ret on root_group alloc failure if !CONFIG_CFQ_GROUP_IOSCHED. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-13 13:11:33 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blkcg: drop unnecessary RCU locking Now that blkg additions / removals are always done under both q and blkcg locks, the only places RCU locking is necessary are blkg_lookup[_create]() for lookup w/o blkcg lock. This patch drops unncessary RCU locking replacing it with plain blkcg locking as necessary. * blkiocg_pre_destroy() already perform proper locking and don't need RCU. Dropped. * blkio_read_blkg_stats() now uses blkcg->lock instead of RCU read lock. This isn't a hot path. * Now unnecessary synchronize_rcu() from queue exit paths removed. This makes q->nr_blkgs unnecessary. Dropped. * RCU annotation on blkg->q removed. -v2: Vivek pointed out that blkg_lookup_create() still needs to be called under rcu_read_lock(). Updated. -v3: After the update, stats_lock locking in blkio_read_blkg_stats() shouldn't be using _irq variant as it otherwise ends up enabling irq while blkcg->lock is locked. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-05 13:15:22 -08:00
block: Move blk_throtl_exit() call to blk_cleanup_queue() Move blk_throtl_exit() in blk_cleanup_queue() as blk_throtl_exit() is written in such a way that it needs queue lock. In blk_release_queue() there is no gurantee that ->queue_lock is still around. Initially blk_throtl_exit() was in blk_cleanup_queue() but Ingo reported one problem. https://lkml.org/lkml/2010/10/23/86 And a quick fix moved blk_throtl_exit() to blk_release_queue(). commit 7ad58c028652753814054f4e3ac58f925e7343f4 Author: Jens Axboe <jaxboe@fusionio.com> Date: Sat Oct 23 20:40:26 2010 +0200 block: fix use-after-free bug in blk throttle code This patch reverts above change and does not try to shutdown the throtl work in blk_sync_queue(). By avoiding call to throtl_shutdown_timer_wq() from blk_sync_queue(), we should also avoid the problem reported by Ingo. blk_sync_queue() seems to be used only by md driver and it seems to be using it to make sure q->unplug_fn is not called as md registers its own unplug functions and it is about to free up the data structures used by unplug_fn(). Block throttle does not call back into unplug_fn() or into md. So there is no need to cancel blk throttle work. In fact I think cancelling block throttle work is bad because it might happen that some bios are throttled and scheduled to be dispatched later with the help of pending work and if work is cancelled, these bios might never be dispatched. Block layer also uses blk_sync_queue() during blk_cleanup_queue() and blk_release_queue() time. That should be safe as we are also calling blk_throtl_exit() which should make sure all the throttling related data structures are cleaned up. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-02 19:05:33 -05:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
block: fix request_queue lifetime handling by making blk_queue_cleanup() properly shutdown request_queue is refcounted but actually depdends on lifetime management from the queue owner - on blk_cleanup_queue(), block layer expects that there's no request passing through request_queue and no new one will. This is fundamentally broken. The queue owner (e.g. SCSI layer) doesn't have a way to know whether there are other active users before calling blk_cleanup_queue() and other users (e.g. bsg) don't have any guarantee that the queue is and would stay valid while it's holding a reference. With delay added in blk_queue_bio() before queue_lock is grabbed, the following oops can be easily triggered when a device is removed with in-flight IOs. sd 0:0:1:0: [sdb] Stopping disk ata1.01: disabled general protection fault: 0000 [#1] PREEMPT SMP CPU 2 Modules linked in: Pid: 648, comm: test_rawio Not tainted 3.1.0-rc3-work+ #56 Bochs Bochs RIP: 0010:[<ffffffff8137d651>] [<ffffffff8137d651>] elv_rqhash_find+0x61/0x100 ... Process test_rawio (pid: 648, threadinfo ffff880019efa000, task ffff880019ef8a80) ... Call Trace: [<ffffffff8137d774>] elv_merge+0x84/0xe0 [<ffffffff81385b54>] blk_queue_bio+0xf4/0x400 [<ffffffff813838ea>] generic_make_request+0xca/0x100 [<ffffffff81383994>] submit_bio+0x74/0x100 [<ffffffff811c53ec>] dio_bio_submit+0xbc/0xc0 [<ffffffff811c610e>] __blockdev_direct_IO+0x92e/0xb40 [<ffffffff811c39f7>] blkdev_direct_IO+0x57/0x60 [<ffffffff8113b1c5>] generic_file_aio_read+0x6d5/0x760 [<ffffffff8118c1ca>] do_sync_read+0xda/0x120 [<ffffffff8118ce55>] vfs_read+0xc5/0x180 [<ffffffff8118cfaa>] sys_pread64+0x9a/0xb0 [<ffffffff81afaf6b>] system_call_fastpath+0x16/0x1b This happens because blk_queue_cleanup() destroys the queue and elevator whether IOs are in progress or not and DEAD tests are sprinkled in the request processing path without proper synchronization. Similar problem exists for blk-throtl. On queue cleanup, blk-throtl is shutdown whether it has requests in it or not. Depending on timing, it either oopses or throttled bios are lost putting tasks which are waiting for bio completion into eternal D state. The way it should work is having the usual clear distinction between shutdown and release. Shutdown drains all currently pending requests, marks the queue dead, and performs partial teardown of the now unnecessary part of the queue. Even after shutdown is complete, reference holders are still allowed to issue requests to the queue although they will be immmediately failed. The rest of teardown happens on release. This patch makes the following changes to make blk_queue_cleanup() behave as proper shutdown. * QUEUE_FLAG_DEAD is now set while holding both q->exit_mutex and queue_lock. * Unsynchronized DEAD check in generic_make_request_checks() removed. This couldn't make any meaningful difference as the queue could die after the check. * blk_drain_queue() updated such that it can drain all requests and is now called during cleanup. * blk_throtl updated such that it checks DEAD on grabbing queue_lock, drains all throttled bios during cleanup and free td when queue is released. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-10-19 14:42:16 +02:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00
blk-throttle: Do not use kblockd workqueue for throtl work o Dominik Klein reported a system hang issue while doing some blkio throttling testing. https://lkml.org/lkml/2011/2/24/173 o Some tracing revealed that CFQ was not dispatching any more jobs as queue unplug was not happening. And queue unplug was not happening because unplug work was not being called as there was one throttling work on same cpu which as not finished yet. And throttling work had not finished as it was tyring to dispatch a bio to CFQ but all the request descriptors were consume to it was put to sleep. o So basically it is a cyclic dependecny between CFQ unplug work and throtl dispatch work. Tejun suggested that use separate workqueue for such cases. o This patch uses a separate workqueue for throttle related work and does not rely on kblockd workqueue anymore. Cc: stable@kernel.org Reported-by: Dominik Klein <dk@in-telegence.net> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-01 13:40:54 -05:00
blkcg: mass rename of blkcg API During the recent blkcg cleanup, most of blkcg API has changed to such extent that mass renaming wouldn't cause any noticeable pain. Take the chance and cleanup the naming. * Rename blkio_cgroup to blkcg. * Drop blkio / blkiocg prefixes and consistently use blkcg. * Rename blkio_group to blkcg_gq, which is consistent with io_cq but keep the blkg prefix / variable name. * Rename policy method type and field names to signify they're dealing with policy data. * Rename blkio_policy_type to blkcg_policy. This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-04-16 13:57:25 -07:00
blkio: Core implementation of throttle policy o Actual implementation of throttling policy in block layer. Currently it implements READ and WRITE bytes per second throttling logic. IOPS throttling comes in later patches. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-15 17:06:35 -04:00