Commit Graph

7371 Commits

Author SHA1 Message Date
Ingo Molnar 8f62242246 perf events: Add generic front-end and back-end stalled cycle event definitions
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>
2011-04-29 14:23:58 +02:00
Ingo Molnar 8a850cadca perf event, x86: Use better stalled cycles metric
Use the UOPS_EXECUTED.*,c=1,i=1 event on Intel CPUs - it is a rather
good indicator of CPU execution stalls, more sensitive and more inclusive
than the 0xa2 resource stalls event (which does not count nearly as many
stall types).

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-7y40wib8n1eqio7hjpn2dsrm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-28 08:39:33 +02:00
Ingo Molnar 5c543e3c44 perf events, x86: Mark constrant tables read mostly
Various constraint tables were not marked read-mostly.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-wpqwwvmhxucy5e718wnamjiv@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 20:04:53 +02:00
Ingo Molnar 94403f8863 perf events: Add stalled cycles generic event - PERF_COUNT_HW_STALLED_CYCLES
The new PERF_COUNT_HW_STALLED_CYCLES event tries to approximate
cycles the CPU does nothing useful, because it is stalled on a
cache-miss or some other condition.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-fue11vymwqsoo5to72jxxjyl@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 20:04:53 +02:00
Ingo Molnar 7bd5fafeb4 Merge branch 'perf/urgent' into perf/stat
Merge reason: We want to queue up dependent changes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 19:36:17 +02:00
Ingo Molnar ec75a71634 perf events, x86: Work around the Nehalem AAJ80 erratum
On Nehalem CPUs the retired branch-misses event can be completely bogus,
when there are no branch-misses occuring. When there are a lot of branch
misses then the count is pretty accurate. Still, this leaves us with an
event that over-counts a lot.

Detect this erratum and work it around by using BR_MISP_EXEC.ANY events.
These will also count speculated branches but still it's a lot more
precise in practice than the architectural event.

Acked-by: 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-yyfg0bxo9jsqxd6a0ovfny27@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 19:34:34 +02:00
Peter Zijlstra 18a073a3ac perf, x86: Fix BTS condition
Currently the x86 backend incorrectly assumes that any BRANCH_INSN
with sample_period==1 is a BTS request. This is not true when we do
frequency driven profiling such as 'perf record -e branches'.

Solves this error:

  $ perf record -e branches ./array
  Error: sys_perf_event_open() syscall returned with 95 (Operation not supported).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: "Metzger, Markus T" <markus.t.metzger@intel.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-rd2y4ct71hjawzz6fpvsy9hg@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 13:34:34 +02:00
Justin P. Mattock fa7b69475a perf events, x86, P4: Fix typo in comment
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: trivial@kernel.org
Link: http://lkml.kernel.org/r/1303492132-3004-1-git-send-email-justinmattock@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-24 13:16:04 +02:00
Linus Torvalds 686c4cbb10 Merge branch 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM: Add missing syscore_suspend() and syscore_resume() calls
  PM: Fix error code paths executed after failing syscore_suspend()
2011-04-23 22:35:16 -07:00
Peter Zijlstra f4929bd372 perf, x86: Update/fix Intel Nehalem cache events
Change the Nehalem cache events to use retired memory instruction counters
(similar to Westmere), this greatly improves the provided stats.

Using:

main ()
{
        int i;

        for (i = 0; i < 1000000000; i++) {
                asm("mov (%%rsp), %%rbx;"
                    "mov %%rbx, (%%rsp);" : : : "rbx");
        }
}

We find:

 $ perf stat --repeat 10 -e instructions:u -e l1-dcache-loads:u -e l1-dcache-stores:u ./loop_1b_loads+stores
  Performance counter stats for './loop_1b_loads+stores' (10 runs):
      4,000,081,056 instructions:u           #      0.000 IPC ( +-   0.000% )
      4,999,502,846 l1-dcache-loads:u          ( +-   0.008% )
      1,000,034,832 l1-dcache-stores:u         ( +-   0.000% )
         1.565184942  seconds time elapsed   ( +-   0.005% )

The 5b is surprising - we'd expect 1b:

 $ perf stat --repeat 10 -e instructions:u -e r10b:u -e l1-dcache-stores:u ./loop_1b_loads+stores
  Performance counter stats for './loop_1b_loads+stores' (10 runs):
      4,000,081,054 instructions:u           #      0.000 IPC ( +-   0.000% )
      1,000,021,961 r10b:u                     ( +-   0.000% )
      1,000,030,951 l1-dcache-stores:u         ( +-   0.000% )
         1.565055422  seconds time elapsed   ( +-   0.003% )

Which this patch thus fixes.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Link: http://lkml.kernel.org/n/tip-q9rtru7b7840tws75xzboapv@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 13:50:27 +02:00
Cyrill Gorcunov 1ea5a6afd9 perf, x86: P4 PMU - Don't forget to clear cpuc->active_mask on overflow
It's not enough to simply disable event on overflow the
cpuc->active_mask should be cleared as well otherwise counter
may stall in "active" even in real being already disabled (which
potentially may lead to the situation that user may not use this
counter further).

Don pointed out that:

 " I also noticed this patch fixed some unknown NMIs
   on a P4 when I stressed the box".

Tested-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Link: http://lkml.kernel.org/r/1303398203-2918-3-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 10:21:34 +02:00
Cyrill Gorcunov 103b393481 perf, x86: P4 PMU -- Use perf_sample_data_init helper
Instead of opencoded assignments better to use
perf_sample_data_init helper.

Tested-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Link: http://lkml.kernel.org/r/1303398203-2918-2-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 10:20:04 +02:00
Ingo Molnar eff430de53 Merge branch 'linus' into perf/core
Merge reason: Pick up upstream fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 10:19:30 +02:00
Ingo Molnar b52c55c6a2 x86, perf event: Turn off unstructured raw event access to offcore registers
Andi Kleen pointed out that the Intel offcore support patches were merged
without user-space tool support to the functionality:

 |
 | The offcore_msr perf kernel code was merged into 2.6.39-rc*, but the
 | user space bits were not. This made it impossible to set the extra mask
 | and actually do the OFFCORE profiling
 |

Andi submitted a preliminary patch for user-space support, as an
extension to perf's raw event syntax:

 |
 | Some raw events -- like the Intel OFFCORE events -- support additional
 | parameters. These can be appended after a ':'.
 |
 | For example on a multi socket Intel Nehalem:
 |
 |    perf stat -e r1b7:20ff -a sleep 1
 |
 | Profile the OFFCORE_RESPONSE.ANY_REQUEST with event mask REMOTE_DRAM_0
 | that measures any access to DRAM on another socket.
 |

But this kind of usability is absolutely unacceptable - users should not
be expected to type in magic, CPU and model specific incantations to get
access to useful hardware functionality.

The proper solution is to expose useful offcore functionality via
generalized events - that way users do not have to care which specific
CPU model they are using, they can use the conceptual event and not some
model specific quirky hexa number.

We already have such generalization in place for CPU cache events,
and it's all very extensible.

"Offcore" events measure general DRAM access patters along various
parameters. They are particularly useful in NUMA systems.

We want to support them via generalized DRAM events: either as the
fourth level of cache (after the last-level cache), or as a separate
generalization category.

That way user-space support would be very obvious, memory access
profiling could be done via self-explanatory commands like:

  perf record -e dram ./myapp
  perf record -e dram-remote ./myapp

... to measure DRAM accesses or more expensive cross-node NUMA DRAM
accesses.

These generalized events would work on all CPUs and architectures that
have comparable PMU features.

( Note, these are just examples: actual implementation could have more
  sophistication and more parameter - as long as they center around
  similarly simple usecases. )

Now we do not want to revert *all* of the current offcore bits, as they
are still somewhat useful for generic last-level-cache events, implemented
in this commit:

  e994d7d23a0b: perf: Fix LLC-* events on Intel Nehalem/Westmere

But we definitely do not yet want to expose the unstructured raw events
to user-space, until better generalization and usability is implemented
for these hardware event features.

( Note: after generalization has been implemented raw offcore events can be
  supported as well: there can always be an odd event that is marginally
  useful but not useful enough to generalize. DRAM profiling is definitely
  *not* such a category so generalization must be done first. )

Furthermore, PERF_TYPE_RAW access to these registers was not intended
to go upstream without proper support - it was a side-effect of the above
e994d7d23a commit, not mentioned in the changelog.

As v2.6.39 is nearing release we go for the simplest approach: disable
the PERF_TYPE_RAW offcore hack for now, before it escapes into a released
kernel and becomes an ABI.

Once proper structure is implemented for these hardware events and users
are offered usable solutions we can revisit this issue.

Reported-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1302658203-4239-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 10:02:53 +02:00
Andi Kleen b2508e828d perf: Support Xeon E7's via the Westmere PMU driver
There's a new model number public, 47, for Xeon E7 (aka Westmere EX).

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/1303429715-10202-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 08:27:29 +02:00
David Rientjes 37f8527dbf Revert "x86, NUMA: Fix fakenuma boot failure"
Andreas Herrmann reported that 7d6b46707f ("x86, NUMA: Fix fakenuma
boot failure") causes certain physical NUMA topologies (for example
AMD Magny-Cours) to move sibling cpus to a single node when in reality
they are in separate domains.

This may result in some nodes being completely void of cpus, which
doesn't accurately represent the correct topology. The system will
boot, but will have suboptimal NUMA performance.

This commit was intended as a fix for NUMA emulation, but should
not cause a regression for real NUMA machines as a side effect.

( There will be a separate fix for the numa-debug code, which
  will not affect physical topologies. )

Reported-by: Andreas Herrmann <herrmann.der.user@googlemail.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1104201918110.12634@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-21 11:30:59 +02:00
Rafael J. Wysocki 19234c0819 PM: Add missing syscore_suspend() and syscore_resume() calls
Device suspend/resume infrastructure is used not only by the suspend
and hibernate code in kernel/power, but also by APM, Xen and the
kexec jump feature.  However, commit 40dc166cb5
(PM / Core: Introduce struct syscore_ops for core subsystems PM)
failed to add syscore_suspend() and syscore_resume() calls to that
code, which generally leads to breakage when the features in question
are used.

To fix this problem, add the missing syscore_suspend() and
syscore_resume() calls to arch/x86/kernel/apm_32.c, kernel/kexec.c
and drivers/xen/manage.c.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
2011-04-20 00:36:11 +02:00
Linus Torvalds 9d914b3ef3 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, gart: Make sure GART does not map physmem above 1TB
  x86, gart: Set DISTLBWALKPRB bit always
  x86, gart: Convert spaces to tabs in enable_gart_translation
2011-04-19 10:58:13 -07:00
Linus Torvalds 96ad999918 Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86: Fix AMD family 15h FPU event constraints
  perf, x86: Fix pre-defined cache-misses event for AMD family 15h cpus
  perf evsel: Fix use of inherit
  perf hists browser: Fix seg fault when annotate null symbol
2011-04-19 10:56:02 -07:00
Robert Richter c8e5910edf perf, x86: Use ALTERNATIVE() to check for X86_FEATURE_PERFCTR_CORE
Using ALTERNATIVE() when checking for X86_FEATURE_PERFCTR_CORE avoids
an extra pointer chase and data cache hit.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1302913676-14352-4-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-19 10:08:12 +02:00
Robert Richter 855357a217 perf, x86: Fix AMD family 15h FPU event constraints
Depending on the unit mask settings some FPU events may be scheduled
only on cpu counter #3. This patch fixes this.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@googlemail.com>
Link: http://lkml.kernel.org/r/1302913676-14352-3-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-19 10:07:55 +02:00
Andre Przywara 83112e688f perf, x86: Fix pre-defined cache-misses event for AMD family 15h cpus
With AMD cpu family 15h a unit mask was introduced for the Data Cache
Miss event (0x041/L1-dcache-load-misses). We need to enable bit 0
(first data cache miss or streaming store to a 64 B cache line) of
this mask to proper count data cache misses.

Now we set this bit for all families and models. In case a PMU does
not implement a unit mask for event 0x041 the bit is ignored.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1302913676-14352-2-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-19 10:07:54 +02:00
Ingo Molnar 68d2cf25d3 Merge branch 'perf/urgent' into perf/core
Merge reason: we'll be queueing up dependent changes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-19 07:56:17 +02:00
Joerg Roedel 665d3e2af8 x86, gart: Make sure GART does not map physmem above 1TB
The GART can only map physical memory below 1TB. Make sure
the gart driver in the kernel does not try to map memory
above 1TB.

Cc: <stable@kernel.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/r/1303134346-5805-5-git-send-email-joerg.roedel@amd.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-04-18 09:26:49 -07:00
Joerg Roedel c34151a742 x86, gart: Set DISTLBWALKPRB bit always
The DISTLBWALKPRB bit must be set for the GART because the
gatt table is mapped UC. But the current code does not set
the bit at boot when the BIOS setup the aperture correctly.
Fix that by setting this bit when enabling the GART instead
of the other places.

Cc: <stable@kernel.org>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/r/1303134346-5805-4-git-send-email-joerg.roedel@amd.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-04-18 09:26:48 -07:00
Joerg Roedel 5bbc097d89 x86, amd: Disable GartTlbWlkErr when BIOS forgets it
This patch disables GartTlbWlk errors on AMD Fam10h CPUs if
the BIOS forgets to do is (or is just too old). Letting
these errors enabled can cause a sync-flood on the CPU
causing a reboot.

The AMD BKDG recommends disabling GART TLB Wlk Error completely.

This patch is the fix for

	https://bugzilla.kernel.org/show_bug.cgi?id=33012

on my machine.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/r/20110415131152.GJ18463@8bytes.org
Tested-by: Alexandre Demers <alexandre.f.demers@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-04-15 16:03:16 -07:00
KOSAKI Motohiro 7d6b46707f x86, NUMA: Fix fakenuma boot failure
Currently, numa=fake boot parameter is broken. If it's used,
kernel may panic due to devide by zero error depending on CPU
configuration

Call Trace:
 [<ffffffff8104ad4c>] find_busiest_group+0x38c/0xd30
 [<ffffffff81086aff>] ? local_clock+0x6f/0x80
 [<ffffffff81050533>] load_balance+0xa3/0x600
 [<ffffffff81050f53>] idle_balance+0xf3/0x180
 [<ffffffff81550092>] schedule+0x722/0x7d0
 [<ffffffff81550538>] ? wait_for_common+0x128/0x190
 [<ffffffff81550a65>] schedule_timeout+0x265/0x320
 [<ffffffff81095815>] ? lock_release_holdtime+0x35/0x1a0
 [<ffffffff81550538>] ? wait_for_common+0x128/0x190
 [<ffffffff8109bb6c>] ? __lock_release+0x9c/0x1d0
 [<ffffffff815534e0>] ? _raw_spin_unlock_irq+0x30/0x40
 [<ffffffff815534e0>] ? _raw_spin_unlock_irq+0x30/0x40
 [<ffffffff81550540>] wait_for_common+0x130/0x190
 [<ffffffff81051920>] ? try_to_wake_up+0x510/0x510
 [<ffffffff8155067d>] wait_for_completion+0x1d/0x20
 [<ffffffff8107f36c>] kthread_create_on_node+0xac/0x150
 [<ffffffff81077bb0>] ? process_scheduled_works+0x40/0x40
 [<ffffffff8155045f>] ? wait_for_common+0x4f/0x190
 [<ffffffff8107a283>] __alloc_workqueue_key+0x1a3/0x590
 [<ffffffff81e0cce2>] cpuset_init_smp+0x6b/0x7b
 [<ffffffff81df3d07>] kernel_init+0xc3/0x182
 [<ffffffff8155d5e4>] kernel_thread_helper+0x4/0x10
 [<ffffffff81553cd4>] ? retint_restore_args+0x13/0x13
 [<ffffffff81df3c44>] ? start_kernel+0x400/0x400
 [<ffffffff8155d5e0>] ? gs_change+0x13/0x13

The divede by zero is caused by the following line,
group->cpu_power==0:

 kernel/sched_fair.c::update_sg_lb_stats()
        /* Adjust by relative CPU power of the group */
        sgs->avg_load = (sgs->group_load * SCHED_LOAD_SCALE) / group->cpu_power;

This regression was caused by commit e23bba6044 ("x86-64, NUMA: Unify
emulated distance mapping") because it changes cpu -> node
mapping in the process of dropping fake_physnodes().

  old) all cpus are assinged node 0
  now) cpus are assigned round robin
       (the logic is implemented by numa_init_array())

  Note: The change in behavior only happens if the system doesn't
        have neither ACPI SRAT table nor AMD northbridge NUMA
	information.

Round robin assignment doesn't work because init_numa_sched_groups_power()
assumes all logical cpus in the same physical cpu share the same node
(then it only accounts for group_first_cpu()), and the simple round robin
breaks the above assumption.

Thus, this patch implements a reassignment of node-ids if buggy firmware
or numa emulation makes wrong cpu node map. Tt enforce all logical cpus
in the same physical cpu share the same node.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/20110415203928.1303.A69D9226@jp.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-15 20:28:19 +02:00
Linus Torvalds 8b9686ff4d Merge branches 'x86-fixes-for-linus', 'sched-fixes-for-linus', 'timers-fixes-for-linus', 'irq-fixes-for-linus' and 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86-32, fpu: Fix FPU exception handling on non-SSE systems
  x86, hibernate: Initialize mmu_cr4_features during boot
  x86-32, NUMA: Fix ACPI NUMA init broken by recent x86-64 change
  x86: visws: Fixup irq overhaul fallout

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Clean up rebalance_domains() load-balance interval calculation

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86/mrst/vrtc: Fix boot crash in mrst_rtc_init()
  rtc, x86/mrst/vrtc: Fix boot crash in rtc_read_alarm()

* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Fix cpumask leak in __setup_irq()

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf probe: Fix listing incorrect line number with inline function
  perf probe: Fix to find recursively inlined function
  perf probe: Fix multiple --vars options behavior
  perf probe: Fix to remove redundant close
  perf probe: Fix to ensure function declared file
2011-04-07 12:12:58 -07:00
H. Peter Anvin 4da9484bde x86, hibernate: Initialize mmu_cr4_features during boot
Restore the initialization of mmu_cr4_features during boot, which was
removed without comment in checkin e5f15b45dd

x86: Cleanup highmap after brk is concluded

thereby breaking resume from hibernate.  This restores previous
functionality in approximately the same place, and corrects the
reading of %cr4 on pre-CPUID hardware (%cr4 exists if and only if
CPUID is supported.)

However, part of the problem is that the hibernate suspend/resume
sequence should manage the save/restore of %cr4 explicitly.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <201104020154.57136.rjw@sisk.pl>
2011-04-06 13:10:02 -07:00
Linus Torvalds d7c764c4c7 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, UV: Fix kdump reboot
  x86, amd-nb: Rename CPU PCI id define for F4
  sound: Add delay.h to sound/soc/codecs/sn95031.c
  x86, mtrr, pat: Fix one cpu getting out of sync during resume
  x86, microcode: Unregister syscore_ops after microcode unloaded
  x86: Stop including <linux/delay.h> in two asm header files
2011-04-04 08:37:45 -07:00
Linus Torvalds fb9a7d76da Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: create new rcu_access_index() and use in mce
  WARN_ON_SMP(): Add comment to explain ({0;})
2011-04-04 08:36:15 -07:00
Paul E. McKenney a4dd99250d rcu: create new rcu_access_index() and use in mce
The MCE subsystem needs to sample an RCU-protected index outside of
any protection for that index.  If this was a pointer, we would use
rcu_access_pointer(), but there is no corresponding rcu_access_index().
This commit therefore creates an rcu_access_index() and applies it
to MCE.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Zdenek Kabelac <zkabelac@redhat.com>
2011-04-01 07:27:31 -07:00
Cliff Wickman 818987e9a1 x86, UV: Fix kdump reboot
After a crash dump on an SGI Altix UV system the crash kernel
fails to cause a reboot.  EFI mode is disabled in the kdump
kernel, so only the reboot_type of BOOT_ACPI works.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: rja@sgi.com
LKML-Reference: <E1Q5Iuo-00013b-UK@eag09.americas.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-31 18:44:03 +02:00
Borislav Petkov cb6c8520f6 x86, amd-nb: Rename CPU PCI id define for F4
With increasing number of PCI function ids, add the PCI function
id in the define name instead of its symbolic name in the BKDG
for more clarity. This renames function 4 define.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
LKML-Reference: <20110330183447.GA3668@aftab>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-31 08:51:38 +02:00
Suresh Siddha 84ac7cdbdd x86, mtrr, pat: Fix one cpu getting out of sync during resume
On laptops with core i5/i7, there were reports that after resume
graphics workloads were performing poorly on a specific AP, while
the other cpu's were ok. This was observed on a 32bit kernel
specifically.

Debug showed that the PAT init was not happening on that AP
during resume and hence it contributing to the poor workload
performance on that cpu.

On this system, resume flow looked like this:

1. BP starts the resume sequence and we reinit BP's MTRR's/PAT
   early on using mtrr_bp_restore()

2. Resume sequence brings all AP's online

3. Resume sequence now kicks off the MTRR reinit on all the AP's.

4. For some reason, between point 2 and 3, we moved from BP
   to one of the AP's. My guess is that printk() during resume
   sequence is contributing to this. We don't see similar
   behavior with the 64bit kernel but there is no guarantee that
   at this point the remaining resume sequence (after AP's bringup)
   has to happen on BP.

5. set_mtrr() was assuming that we are still on BP and skipped the
   MTRR/PAT init on that cpu (because of 1 above)

6. But we were on an AP and this led to not reprogramming PAT
   on this cpu leading to bad performance.

Fix this by doing unconditional mtrr_if->set_all() in set_mtrr()
during MTRR/PAT init. This might be unnecessary if we are still
running on BP. But it is of no harm and will guarantee that after
resume, all the cpu's will be in sync with respect to the
MTRR/PAT registers.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1301438292-28370-1-git-send-email-eric@anholt.net>
Signed-off-by: Eric Anholt <eric@anholt.net>
Tested-by: Keith Packard <keithp@keithp.com>
Cc: stable@kernel.org	[v2.6.32+]
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-03-29 16:17:42 -07:00
Thomas Gleixner 86cc8dfc21 x86: apb_timer: Fixup genirq fallout
The lonely user of the internal interface was not in the coccinelle
script.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-30 00:13:30 +02:00
Xiaotian Feng 4ac5fc6a3e x86, microcode: Unregister syscore_ops after microcode unloaded
Currently, microcode doesn't unregister syscore_ops after it's
unloaded. So if we modprobe then rmmod microcode, the stale
microcode syscore_ops info will stay on syscore_ops_list.

Later when we're trying to reboot/halt/shutdown the machine, kernel
will panic on syscore_shutdown().

With the patch applied, I can reboot/halt/shutdown my machine successfully.

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
LKML-Reference: <1301387672-23661-1-git-send-email-dfeng@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-29 11:12:04 +02:00
Jean Delvare ca444564a9 x86: Stop including <linux/delay.h> in two asm header files
Stop including <linux/delay.h> in x86 header files which don't
need it. This will let the compiler complain when this header is
not included by source files when it should, so that
contributors can fix the problem before building on other
architectures starts to fail.

Credits go to Geert for the idea.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: James E.J. Bottomley <James.Bottomley@suse.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <20110325152014.297890ec@endymion.delvare>
[ this also fixes an upstream build bug in drivers/media/rc/ite-cir.c ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-29 09:37:42 +02:00
Cyrill Gorcunov 1d321881af perf, x86: P4 PMU - clean up the code a bit
No change on the functional level, just align the table properly.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <4D8FA213.5050108@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-29 09:36:33 +02:00
Linus Torvalds 16c29dafcc Merge branch 'syscore' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'syscore' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  Introduce ARCH_NO_SYSDEV_OPS config option (v2)
  cpufreq: Use syscore_ops for boot CPU suspend/resume (v2)
  KVM: Use syscore_ops instead of sysdev class and sysdev
  PCI / Intel IOMMU: Use syscore_ops instead of sysdev class and sysdev
  timekeeping: Use syscore_ops instead of sysdev class and sysdev
  x86: Use syscore_ops instead of sysdev classes and sysdevs
2011-03-25 21:07:59 -07:00
Linus Torvalds 95e14ed7fc Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  kdb: add usage string of 'per_cpu' command
  kgdb,x86_64: fix compile warning found with sparse
  kdb: code cleanup to use macro instead of value
  kgdboc,kgdbts: strlen() doesn't count the terminator
2011-03-25 21:04:56 -07:00
Linus Torvalds 2a20b02c05 Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86: Complain louder about BIOSen corrupting CPU/PMU state and continue
  perf, x86: P4 PMU - Read proper MSR register to catch unflagged overflows
  perf symbols: Look at .dynsym again if .symtab not found
  perf build-id: Add quirk to deal with perf.data file format breakage
  perf session: Pass evsel in event_ops->sample()
  perf: Better fit max unprivileged mlock pages for tools needs
  perf_events: Fix stale ->cgrp pointer in update_cgrp_time_from_cpuctx()
  perf top: Fix uninitialized 'counter' variable
  tracing: Fix set_ftrace_filter probe function display
  perf, x86: Fix Intel fixed counters base initialization
2011-03-25 17:53:09 -07:00
Linus Torvalds 94df491c4a Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  futex: Fix WARN_ON() test for UP
  WARN_ON_SMP(): Allow use in if() statements on UP
  x86, dumpstack: Use %pB format specifier for stack trace
  vsprintf: Introduce %pB format specifier
  lockdep: Remove unused 'factor' variable from lockdep_stats_show()
2011-03-25 17:52:22 -07:00
Linus Torvalds 26ff6801f7 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: DT: Cleanup namespace and call irq_set_irq_type() unconditional
  x86: DT: Fix return condition in irq_create_of_mapping()
  x86, mpparse: Move check_slot into CONFIG_X86_IO_APIC context
2011-03-25 17:51:51 -07:00
Jason Wessel 21431c2900 kgdb,x86_64: fix compile warning found with sparse
Fix sparse warning:

arch/x86/kernel/kgdb.c:123:9: warning: switch with no cases

Reported-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-03-25 16:37:31 -05:00
Ingo Molnar 45daae575e perf, x86: Complain louder about BIOSen corrupting CPU/PMU state and continue
Eric Dumazet reported that hardware PMU events do not work on his
system, due to the BIOS corrupting PMU state:

    Performance Events: PEBS fmt0+, Core2 events, Broken BIOS detected, using software events only.
    [Firmware Bug]: the BIOS has corrupted hw-PMU resources (MSR 186 is 43003c)

Linus suggested that we continue in the face of such BIOS-induced CPU
state corruption:

   http://lkml.org/lkml/2011/3/24/608

Such BIOSes will have to be fixed - Linux developers rely on a working and
fully capable PMU and the BIOS interfering with the CPU's PMU state is simply
not acceptable.

So this patch changes perf to continue when it detects such BIOS
interaction, some hardware events may be unreliable due to the BIOS
writing and re-writing them - there's not much the kernel can do
about that but to detect the corruption and report it.

Reported-and-tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-25 11:23:41 +01:00
Thomas Gleixner 07611dbda5 x86: DT: Cleanup namespace and call irq_set_irq_type() unconditional
That call escaped the name space cleanup. Fix it up.

We really want to call there. The chip might have changed since the
irq was setup initially. So let the core code and the chip decide what
to do. The status is just an unreliable snapshot.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-03-24 23:17:56 +01:00
Thomas Gleixner 00a30b254b x86: DT: Fix return condition in irq_create_of_mapping()
The xlate() function returns 0 or a negative error code. Returning the
error code blindly will be seen as an huge irq number by the calling
function because irq_create_of_mapping() returns an unsigned value.

Return 0 (NO_IRQ) as required.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-03-24 23:17:56 +01:00
Don Zickus 242214f9c1 perf, x86: P4 PMU - Read proper MSR register to catch unflagged overflows
The read of a proper MSR register was missed and instead of
counter the configration register was tested (it has
ARCH_P4_UNFLAGGED_BIT always cleared) leading to unknown NMI
hitting the system. As result the user may obtain "Dazed and
confused, but trying to continue" message. Fix it by reading a
proper MSR register.

When an NMI happens on a P4, the perf nmi handler checks the
configuration register to see if the overflow bit is set or not
before taking appropriate action.  Unfortunately, various P4
machines had a broken overflow bit, so a backup mechanism was
implemented.  This mechanism checked to see if the counter
rolled over or not.

A previous commit that implemented this backup mechanism was
broken. Instead of reading the counter register, it used the
configuration register to determine if the counter rolled over
or not. Reading that bit would give incorrect results.

This would lead to 'Dazed and confused' messages for the end
user when using the perf tool (or if the nmi watchdog is
running).

The fix is to read the counter register before determining if
the counter rolled over or not.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <4D8BAB49.3080701@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-24 21:40:01 +01:00
Linus Torvalds 047f61c5d1 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (42 commits)
  ACPI: minor printk format change in acpi_pad
  ACPI: make acpi_pad /sys output more readable
  ACPICA: Update version to 20110316
  ACPICA: Header support for SLIC table
  ACPI: Make sure the FADT is at least rev 2 before using the reset register
  ACPI: Bug compatibility for Windows on the ACPI reboot vector
  ACPICA: Fix access width for reset vector
  ACPI battery: fribble sysfs files from a resume notifier
  ACPI button: remove unused procfs I/F
  ACPI, APEI, Add PCIe AER error information printing support
  PCIe, AER, use pre-generated prefix in error information printing
  ACPI, APEI, Add ERST record ID cache
  ACPI: Use syscore_ops instead of sysdev class and sysdev
  ACPI: Remove the unused EC sysdev class
  ACPI: use __cpuinit for the acpi_processor_set_pdc() call tree
  ACPI: use __init where possible in processor driver
  Thermal_Framework-Fix_crash_during_hwmon_unregister
  ACPICA: Update version to 20110211.
  ACPICA: Add mechanism to defer _REG methods for some installed handlers
  ACPICA: Add support for FunctionalFixedHW in acpi_ut_get_region_name
  ...
2011-03-24 08:25:15 -07:00