amdtopology is going to be used by 32bit too drop _64 suffix. This is
pure rename.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
numa_init_array() no longer has users outside of numa.c. Make it
static.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
With both _numa_init() methods converted and the rest of init code
adjusted, numa_32.c now can switch from the 32bit only init code to
the common one in numa.c.
* Shim get_memcfg_*()'s are dropped and initmem_init() calls
x86_numa_init(), which is updated to handle NUMAQ.
* All boilerplate operations including node range limiting, pgdat
alloc/init are handled by numa_init(). 32bit only implementation is
removed.
* 32bit numa_add_memblk(), numa_set_distance() and
memory_add_physaddr_to_nid() removed and common versions in
numa_32.c enabled for 32bit.
This change causes the following behavior changes.
* NODE_DATA()->node_start_pfn/node_spanned_pages properly initialized
for 32bit too.
* Much more sanity checks and configuration cleanups.
* Proper handling of node distances.
* The same NUMA init messages as 64bit.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
setup_node_bootmem() is taken from 64bit and doesn't use remap
allocator. It's about to be shared with 32bit so add support for it.
If NODE_DATA is remapped, it's noted in the debug message and node
locality check is skipped as the __pa() of the remapped address
doesn't reflect the actual physical address.
On 64bit, remap allocator becomes noop and doesn't affect the
behavior.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Instead of dereferencing node_start/end_pfn[] directly, make
init_alloc_remap() take @start and @end and let the caller be
responsible for making sure the range is sane. This is to prepare for
use from unified NUMA init code.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Code moved from numa_64.c has assumption that long is 64bit in several
places. This patch removes the assumption by using {s|u}64_t
explicity, using PFN_PHYS() for page number -> addr conversions and
adjusting printf formats.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Generic NUMA init code was moved to numa.c from numa_64.c but is still
guaraded by CONFIG_X86_64. This patch removes the compile guard and
enables compiling on 32bit.
* numa_add_memblk() and numa_set_distance() clash with the shim
implementation in numa_32.c and are left out.
* memory_add_physaddr_to_nid() clashes with 32bit implementation and
is left out.
* MAX_DMA_PFN definition in dma.h moved out of !CONFIG_X86_32.
* node_data definition in numa_32.c removed in favor of the one in
numa.c.
There are places where ulong is assumed to be 64bit. The next patch
will fix them up. Note that although the code is compiled it isn't
used yet and this patch doesn't cause any functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Move the generic 64bit NUMA init machinery from numa_64.c to numa.c.
* node_data[], numa_mem_info and numa_distance
* numa_add_memblk[_to](), numa_remove_memblk[_from]()
* numa_set_distance() and friends
* numa_init() and all the numa_meminfo handling helpers called from it
* dummy_numa_init()
* memory_add_physaddr_to_nid()
A new function x86_numa_init() is added and the content of
numa_64.c::initmem_init() is moved into it. initmem_init() now simply
calls x86_numa_init().
Constants and numa_off declaration are moved from numa_{32|64}.h to
numa.h.
This is code reorganization and doesn't involve any functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Update numaq such that it calls numa_add_memblk() and sets
numa_nodes_parsed instead of directly diddling with NUMA states. The
original get_memcfg_numaq() is renamed to numaq_numa_init() and new
get_memcfg_numaq() is created in numa_32.c.
The shim numa_add_memblk() implementation handles node_start/end_pfn[]
and node_set_online() for nodes with memory. The new
get_memcfg_numaq() exactly the same with get_memcfg_from_srat() other
than calling the numaq init function. Things get_memcfgs_numaq() do
are not strictly necessary for numaq but added for consistency and to
help unifying NUMA init handling.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
SRAT support implementation in srat_32.c and srat.c are generally
similar; however, there are some differences.
First of all, 64bit implementation supports more types of SRAT
entries. 64bit supports x2apic, affinity, memory and SLIT. 32bit
only supports processor and memory.
Most other differences stem from different initialization protocols
employed by 64bit and 32bit NUMA init paths.
On 64bit,
* Mappings among PXM, node and apicid are directly done in each SRAT
entry callback.
* Memory affinity information is passed to numa_add_memblk() which
takes care of all interfacing with NUMA init.
* Doesn't directly initialize NUMA configurations. All the
information is recorded in numa_nodes_parsed and memblks.
On 32bit,
* Checks numa_off.
* Things go through one more level of indirection via private tables
but eventually end up initializing the same mappings.
* node_start/end_pfn[] are initialized and
memblock_x86_register_active_regions() is called for each memory
chunk.
* node_set_online() is called for each online node.
* sort_node_map() is called.
There are also other minor differences in sanity checking and messages
but taking 64bit version should be good enough.
This patch drops the 32bit specific implementation and makes the 64bit
implementation common for both 32 and 64bit.
The init protocol differences are dealt with in two places - the
numa_add_memblk() shim added in the previous patch and new temporary
numa_32.c:get_memcfg_from_srat() which wraps invocation of
x86_acpi_numa_init().
The shim numa_add_memblk() handles the folowings.
* node_start/end_pfn[] initialization.
* node_set_online() for memory nodes.
* Invocation of memblock_x86_register_active_regions().
The shim get_memcfg_from_srat() handles the followings.
* numa_off check.
* node_set_online() for CPU nodes.
* sort_node_map() invocation.
* Clearing of numa_nodes_parsed and active_ranges on failure.
The shims are temporary and will be removed as the generic NUMA init
path in 32bit is replaced with 64bit one.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
To help transition to common NUMA init, implement temporary 32bit
shims for numa_add_memblk() and numa_set_distance().
numa_add_memblk() registers the memblk and adjusts
node_start/end_pfn[]. numa_set_distance() is noop.
These shims will allow using 64bit NUMA init functions on 32bit and
gradual transition to common NUMA init path.
For detailed description, please read description of commits which
make use of the shim functions.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Move numa_nodes_parsed from numa_64.[hc] to numa.[hc] to prepare for
NUMA init path unification.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
There's no reason get_memcfg_numa() to be implemented inline in
mmzone_32.h. Move it to numa_32.c and also make
get_memcfg_numa_flag() static.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Make srat.c 32bit safe by removing the assumption that unsigned long
is 64bit.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Rename srat_64.c to srat.c. This is to prepare for unification of
NUMA init paths between 32 and 64bit.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
* Kill no longer used struct bootnode.
* Kill dangling declaration of pxm_to_nid() in numa_32.h.
* Make setup_node_bootmem() static.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Instead of calling memory_present() for each region from NUMA init,
call sparse_memory_present_with_active_regions() from paging_init()
similarly to x86-64.
For flat and numaq, this results in exactly the same memory_present()
calls. For srat, if there are multiple memory chunks for a node,
after this change, memory_present() will be called separately for each
chunk instead of being called once to encompass the whole range, which
doesn't cause any harm and actually is the better behavior.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
NUMAQ is the only meaningful user of this callback and
setup_local_APIC() the only callsite. Stop torturing everyone else by
making the callback optional and removing all the boilerplate
implementations and assignments.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Currently, the only meaningful user of apic->x86_32_numa_cpu_node() is
NUMAQ which returns valid mapping only after CPU is initialized during
SMP bringup; thus, the previous patch to set apicid -> node in
setup_local_APIC() makes __apicid_to_node[] always contain the correct
mapping whether custom apic->x86_32_numa_cpu_node() is used or not.
So, there is no reason to keep separate 32bit implementation. We can
always consult __apicid_to_node[]. Move 64bit implementation from
numa_64.c to numa.c and remove 32bit implementation from numa_32.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Some x86-32 NUMA implementations (NUMAQ) don't initialize apicid ->
node mapping using set_apicid_to_node() during NUMA init but implement
custom apic->x86_32_numa_cpu_node() instead.
This patch automatically initializes the default apic -> node mapping
table from apic->x86_32_numa_cpu_node() from setup_local_APIC() such
that the mapping table is in sync with the actual mapping.
As the table isn't used by custom implementations, this doesn't make
any difference at this point. This is in preparation of unifying
numa_cpu_node() between x86-32 and 64.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
With top-down memblock allocation, the allocation range limits in
ealry_node_mem() can be simplified - try node-local first, then any
node but in any case don't allocate below DMA limit.
Remove early_node_mem() and implement simplified allocation directly
in setup_node_bootmem().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Make the following trivial changes in preparation for further updates.
* nodeid -> nid, nid -> tnid
* use nd_ prefix for nodedata related variables
* remove start/end_pfn and use start/end directly
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
The only special handling NUMA needs to do for hotadd memory is
determining the node for the hotadd memory given the address of it and
there's nothing specific to specific config method used.
srat_64.c does somewhat elaborate error checking on
ACPI_SRAT_MEM_HOT_PLUGGABLE regions, remembers them and implements
memory_add_physaddr_to_nid() which determines the node for given
hotadd address.
This is almost completely redundant. All the information is already
available to the generic NUMA code which already performs all the
sanity checking and merging. All that's necessary is not using
__initdata from numa_meminfo and providing a function which uses it to
map address to node.
Drop the specific implementation from srat_64.c and add generic
memory_add_physaddr_to_nid() in numa_64.c, which is enabled if
CONFIG_MEMORY_HOTPLUG is set. Other than dropping the code, srat_64.c
doesn't need any change as it already calls numa_add_memblk() for hot
pluggable regions which is enough.
While at it, change CONFIG_MEMORY_HOTPLUG_SPARSE in srat_64.c to
CONFIG_MEMORY_HOTPLUG, for NUMA on x86-64, the two are always the
same.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Merge reason: Pick up the following two fix commits.
2be19102b7: x86, NUMA: Fix empty memblk detection in numa_cleanup_meminfo()
765af22da8: x86-32, NUMA: Fix ACPI NUMA init broken by recent x86-64 change
Scheduled NUMA init 32/64bit unification changes depend on these.
Signed-off-by: Tejun Heo <tj@kernel.org>
numa_cleanup_meminfo() trims each memblk between low (0) and
high (max_pfn) limits and discards empty ones. However, the
emptiness detection incorrectly used equality test. If the
start of a memblk is higher than max_pfn, it is empty but fails
the equality test and doesn't get discarded.
The condition triggers when max_pfn is lower than start of a
NUMA node and results in memory misconfiguration - leading to
WARN_ON()s and other funnies. The bug was discovered in devel
branch where 32bit too uses this code path for NUMA init. If a
node is above the addressing limit, max_pfn ends up lower than
the node triggering this problem.
The failure hasn't been observed on x86-64 but is still possible
with broken hardware e820/NUMA info. As the fix is very low
risk, it would be better to apply it even for 64bit.
Fix it by using >= instead of ==.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Extracted the actual fix from the original patch and rewrote patch description. ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110501171204.GO29280@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Older AMD K8 processors (Revisions A-E) are affected by erratum
400 (APIC timer interrupts don't occur in C states greater than
C1). This, for example, means that X86_FEATURE_ARAT flag should
not be set for these parts.
This addresses regression introduced by commit
b87cf80af3 ("x86, AMD: Set ARAT
feature on AMD processors") where the system may become
unresponsive until external interrupt (such as keyboard input)
occurs. This results, for example, in time not being reported
correctly, lack of progress on the system and other lockups.
Reported-by: Joerg-Volker Peetz <jvpeetz@web.de>
Tested-by: Joerg-Volker Peetz <jvpeetz@web.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Boris Ostrovsky <Boris.Ostrovsky@amd.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1304113663-6586-1-git-send-email-ostr@amd64.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Many different platforms and subsystems may want to disable device
clocks during suspend and enable them during resume which is going to
be done in a very similar way in all those cases. For this reason,
provide generic routines for the manipulation of device clocks during
suspend and resume.
Convert the ARM shmobile platform to using the new routines.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf, x86, nmi: Move LVT un-masking into irq handlers
perf events, x86: Work around the Nehalem AAJ80 erratum
perf, x86: Fix BTS condition
ftrace: Build without frame pointers on Microblaze
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: ce4100: Configure IOAPIC pins for USB and SATA to level type
x86: devicetree: Configure IOAPIC pin only once
x86, setup: When probing memory with e801, use ax/bx as a pair
Make the comments a bit clearer for get_bios_ebda so that it actually
tells us what it is returning.
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add a wrapper routine that tells us the length of the EBDA if it is
present. This guy also ensures that the returned length doesn't let the
EBDA run past the 640KiB mark.
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes sure that when a driver calls the ethtool's
get/set_settings() callback of another driver, the data passed to it
is clean. This guarantees that speed_hi will be zeroed correctly if
the called callback doesn't explicitely set it: we are sure we don't
get a corrupted speed from the underlying driver. We also take care of
setting the cmd field appropriately (ETHTOOL_GSET/SSET).
This applies to dev_ethtool_get_settings(), which now makes sure it
sets up that ethtool command parameter correctly before passing it to
drivers. This also means that whoever calls dev_ethtool_get_settings()
does not have to clean the ethtool command parameter. This function
also becomes an exported symbol instead of an inline.
All drivers visible to make allyesconfig under x86_64 have been
updated.
Signed-off-by: David Decotigny <decot@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
OMAP3+: voltage: remove initial voltage
OMAP4: Intialize IVA Device in addition to DSP device.
omap: rx51: mark reserved memory earlier
OMAP3: l3: fix for "irq 10: nobody cared" message
arm: omap2: enable smc instruction for sleep34xx
OMAP2/3: hwmod: fix gpio-reset timeouts seen during bootup.
OMAP3: PM: Do not rely on ROM code to restore CM_AUTOIDLE_PLL.AUTO_PERIPH_DPLL
OMAP2+: PM: Fix the saving of CM_AUTOIDLE_PLL register on scratchpad area
OMAP4: clock data: Change DSS clock aliases
OMAP2+: hwmod data: Fix wrong dma_system end address
When CONFIG_OABI_COMPAT is set, the wrapper for semtimedop does not
bound the nsops argument. A sufficiently large value will cause an
integer overflow in allocation size, followed by copying too much data
into the allocated buffer. Fix this by restricting nsops to SEMOPM.
Untested.
Cc: stable@kernel.org
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Extend the Intel Westmere PMU driver with definitions for generic front-end and
back-end stall events.
( These are only approximations. )
Reported-by: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n008io7hjpn1dsrm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Extend the Intel and AMD event definitions with generic front-end and
back-end stall events.
( These are only approximations - suggestions are welcome for better events. )
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n001io7hjpn1dsrm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add two generic hardware events: front-end and back-end stalled cycles.
These events measure conditions when the CPU is executing code but its
capabilities are not fully utilized. Understanding such situations and
analyzing them is an important sub-task of code optimization workflows.
Both events limit performance: most front end stalls tend to be caused
by branch misprediction or instruction fetch cachemisses, backend
stalls can be caused by various resource shortages or inefficient
instruction scheduling.
Front-end stalls are the more important ones: code cannot run fast
if the instruction stream is not being kept up.
An over-utilized back-end can cause front-end stalls and thus
has to be kept an eye on as well.
The exact composition is very program logic and instruction mix
dependent.
We use the terms 'stall', 'front-end' and 'back-end' loosely and
try to use the best available events from specific CPUs that
approximate these concepts.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n000io7hjpn1dsrm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
pfault, dasd diag and virtio all use the same external interrupt number.
The respective interrupt handlers decide by the subcode if they are
meant to handle the interrupt.
Counting is currently done before looking at the subcode which means
each handler counts an interrupt even if it is not handling it.
Fix this by moving the kstat code after the code which looks at the
subcode.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
While tracking down the reason for an ioremap() failure I was
distracted by the WARN_ONCE() in __ioremap_caller().
Performing a WARN_ONCE() sanity check before the mapping
is successful seems pointless if the caller sends bad values.
A case in point is when the BIOS provides erroneous screen_info
values causing vesafb_probe() to request an outrageuous size.
The WARN_ONCE is then wasted on bogosity. Move the warning to a
point where the mapping has been successfully allocated.
Addresses:
http://bugs.launchpad.net/bugs/772042
Reviewed-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Link: http://lkml.kernel.org/r/4DB99D2E.9080106@canonical.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
- Remove coding standard violations reported by checkpatch.pl
- Delete comment about handling of conditional branches which is no
longer true.
- Delete comment at end of file which lists all ARM instructions. This
duplicates data available in the ARM ARM and seems like an
unnecessary maintenance burden to keep this up to date and accurate.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Being able to probe NOP instructions is useful for hard-coding probeable
locations and is used by the kprobes test code.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
These bit field manipulation instructions occur several thousand
times in an ARMv7 kernel.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
The MOVW and MOVT instructions account for approximately 7% of all
instructions in a ARMv7 kernel as GCC uses them instead of a literal
pool.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
The instruction decoding in space_cccc_000x needs to reject probing of
instructions with undefined patterns as they may in future become
defined and then emulated faultily - as has already happened with the
SMC instruction.
This fix is achieved by testing for the instruction patterns we want to
probe and making the the default fall-through paths reject probes. This
also allows us to remove some explicit tests for instructions that we
wish to reject, as that is now the default action.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
The tests to explicitly reject probing CPS, RFE and SRS instructions
are redundant as the default case is now to reject undecoded patterns.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
The PLD instructions wasn't being decoded correctly and the emulation
code wasn't adjusting PC correctly.
As the PLD instruction is only a performance hint we emulate it as a
simple nop, and we can broaden the instruction decoding to take into
account newer PLI and PLDW instructions.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
