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  1. 29 1月, 2010 5 次提交
  3. 28 1月, 2010 1 次提交
    • A
      perf: Fix inconsistency between IP and callchain sampling · 339ce1a4
      由 Anton Blanchard 提交于 
      When running perf across all cpus with backtracing (-a -g), sometimes we
get samples without associated backtraces:

    23.44%         init  [kernel]                     [k] restore
    11.46%         init                       eeba0c  [k] 0x00000000eeba0c
     6.77%      swapper  [kernel]                     [k] .perf_ctx_adjust_freq
     5.73%         init  [kernel]                     [k] .__trace_hcall_entry
     4.69%         perf  libc-2.9.so                  [.] 0x0000000006bb8c
                       |
                       |--11.11%-- 0xfffa941bbbc

It turns out the backtrace code has a check for the idle task and the IP
sampling does not. This creates problems when profiling an interrupt
heavy workload (in my case 10Gbit ethernet) since we get no backtraces
for interrupts received while idle (ie most of the workload).

Right now x86 and sh check that current is not NULL, which should never
happen so remove that too.

Idle task's exclusion must be performed from the core code, on top
of perf_event_attr:exclude_idle.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
LKML-Reference: <20100118054707.GT12666@kryten>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      339ce1a4
  5. 13 1月, 2010 1 次提交
  7. 31 12月, 2009 1 次提交
    • F
      perf: Pass appropriate frame pointer to dump_trace() · 48b5ba9c
      由 Frederic Weisbecker 提交于 
      Pass the frame pointer from the regs of the interrupted path
to dump_trace() while processing the stack trace.

Currently, dump_trace() takes the current bp and starts the
callchain from dump_trace() itself. This is wasteful because
we need to walk through the entire NMI/DEBUG stack before
retrieving the interrupted point.

We can fix that by just using the frame pointer from the
captured regs. It points exactly where we want to start.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1262235183-5320-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
      48b5ba9c
  9. 17 12月, 2009 2 次提交
    • F
      perf events, x86/stacktrace: Fix performance/softlockup by providing a special... · 06d65bda
      由 Frederic Weisbecker 提交于 
      perf events, x86/stacktrace: Fix performance/softlockup by providing a special frame pointer-only stack walker

It's just wasteful for stacktrace users like perf to walk
through every entries on the stack whereas these only accept
reliable ones, ie: that the frame pointer validates.

Since perf requires pure reliable stacktraces, it needs a stack
walker based on frame pointers-only to optimize the stacktrace
processing.

This might solve some near-lockup scenarios that can be triggered
by call-graph tracing timer events.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1261024834-5336-2-git-send-regression-fweisbec@gmail.com>
[ v2: fix for modular builds and small detail tidyup ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      06d65bda
    • F
      perf events, x86/stacktrace: Make stack walking optional · 61c1917f
      由 Frederic Weisbecker 提交于 
      The current print_context_stack helper that does the stack
walking job is good for usual stacktraces as it walks through
all the stack and reports even addresses that look unreliable,
which is nice when we don't have frame pointers for example.

But we have users like perf that only require reliable
stacktraces, and those may want a more adapted stack walker, so
lets make this function a callback in stacktrace_ops that users
can tune for their needs.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1261024834-5336-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      61c1917f
  11. 11 12月, 2009 2 次提交
  13. 06 12月, 2009 1 次提交
    • F
      x86/perf: Exclude the debug stack from the callchains · 7f33f9c5
      由 Frederic Weisbecker 提交于 
      Dumping the callchains from breakpoint events with perf gives strange
results:

3.75%             perf  [kernel]           [k] _raw_read_unlock
                       |
                       --- _raw_read_unlock
                           perf_callchain
                           perf_prepare_sample
                           __perf_event_overflow
                           perf_swevent_overflow
                           perf_swevent_add
                           perf_bp_event
                           hw_breakpoint_exceptions_notify
                           notifier_call_chain
                           __atomic_notifier_call_chain
                           atomic_notifier_call_chain
                           notify_die
                           do_debug
                           debug
                           munmap

We are infected with all the debug stack. Like the nmi stack, the debug
stack is undesired as it is part of the profiling path, not helpful for
the user.

Ignore it.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
      7f33f9c5
  15. 04 12月, 2009 1 次提交
  17. 25 11月, 2009 1 次提交
    • S
      perf_events, x86: Fix validate_event bug · 1261a02a
      由 Stephane Eranian 提交于 
      The validate_event() was failing on valid event combinations. The
function was assuming that if x86_schedule_event() returned 0, it
meant error. But x86_schedule_event() returns the counter index and
0 is a perfectly valid value. An error is returned if the function
returns a negative value.

Furthermore, validate_event() was also failing for event groups
because the event->pmu was not set until after
hw_perf_event_init().
Signed-off-by: NStephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: perfmon2-devel@lists.sourceforge.net
Cc: eranian@gmail.com
LKML-Reference: <4b0bdf36.1818d00a.07cc.25ae@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
--
 arch/x86/kernel/cpu/perf_event.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
      1261a02a
  19. 12 11月, 2009 1 次提交
  21. 13 10月, 2009 1 次提交
    • I
      perf_events, x86: Fix event constraints code · 7a693d3f
      由 Ingo Molnar 提交于 
      There was namespace overlap due to a rename i did - this caused
the following build warning, reported by Stephen Rothwell against
linux-next x86_64 allmodconfig:

  arch/x86/kernel/cpu/perf_event.c: In function 'intel_get_event_idx':
  arch/x86/kernel/cpu/perf_event.c:1445: warning: 'event_constraint' is used uninitialized in this function

This is a real bug not just a warning: fix it by renaming the
global event-constraints table pointer to 'event_constraints'.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091013144223.369d616d.sfr@canb.auug.org.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      7a693d3f
  23. 09 10月, 2009 3 次提交
  25. 23 9月, 2009 1 次提交
    • P
      perf_event, x86: Fix 'perf sched record' crashing the machine · 7d428966
      由 Peter Zijlstra 提交于 
      Chris Malley reported that 'perf sched record' sometimes
crashes his box with:

[  389.272175] BUG: unable to handle kernel paging request at ffffb300
[  389.272294] IP: [<c011b0bd>] default_send_IPI_self+0x1d/0x50
[  389.272366] *pde = 0073f067 *pte = 00000000
[  389.274708] Call Trace:
[  389.274752]  [<c010e3b4>] ?  set_perf_event_pending+0x14/0x20
[  389.274801]  [<c01b9751>] ?  perf_output_unlock+0x121/0x1a0
[  389.274848]  [<c01b981a>] ? perf_output_end+0x4a/0x70
[  389.274893]  [<c01ba690>] ?  __perf_event_overflow+0x240/0x2f0
[  389.274942]  [<c030963e>] ? atomic64_cmpxchg+0x1e/0x30
[  389.274988]  [<c01ba8f4>] ?  perf_swevent_ctx_event+0x1b4/0x1c0
[  389.275035]  [<c01ba773>] ?  perf_swevent_ctx_event+0x33/0x1c0
[  389.275081]  [<c01ba9a7>] ? do_perf_sw_event+0xa7/0x160
[  389.275127]  [<c01baae2>] ? perf_tp_event+0x82/0xa0
[  389.275174]  [<c012e9c6>] ?  ftrace_profile_sched_stat_runtime+0xe6/0x120
[  389.275224]  [<c012e8e0>] ?  ftrace_profile_sched_stat_runtime+0x0/0x120
[  389.275273]  [<c013c85a>] ? update_curr+0x18a/0x230
[  389.275318]  [<c013cdc5>] ?  put_prev_task_fair+0x155/0x160
[  389.275366]  [<c01618b5>] ? sched_clock_cpu+0xd5/0x110
[  389.275413]  [<c04e7525>] ? _spin_lock_irq+0x45/0x50
[  389.275458]  [<c04e424e>] ? schedule+0x20e/0xb10

The problem is that the box has no lapic enabled:

  [    0.042445] Local APIC not detected. Using dummy APIC emulation.

The below seems like the best fix. We disabled all lapic bits, except
the self-IPI-resend logic.
Reported-by: NChris Malley <mail@chrismalley.co.uk>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <7863dc4c0909221409v7893bfd3o4b590d5951a233ba@mail.gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      7d428966
  27. 21 9月, 2009 4 次提交
    • I
      perf: Tidy up after the big rename · 57c0c15b
      由 Ingo Molnar 提交于 
       - provide compatibility Kconfig entry for existing PERF_COUNTERS .config's

 - provide courtesy copy of old perf_counter.h, for user-space projects

 - small indentation fixups

 - fix up MAINTAINERS

 - fix small x86 printout fallout

 - fix up small PowerPC comment fallout (use 'counter' as in register)
Reviewed-by: NArjan van de Ven <arjan@linux.intel.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      57c0c15b
    • I
      perf: Do the big rename: Performance Counters -> Performance Events · cdd6c482
      由 Ingo Molnar 提交于 
      Bye-bye Performance Counters, welcome Performance Events!

In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.

Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.

All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)

The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.

Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.

User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)

This patch has been generated via the following script:

  FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

  sed -i \
    -e 's/PERF_EVENT_/PERF_RECORD_/g' \
    -e 's/PERF_COUNTER/PERF_EVENT/g' \
    -e 's/perf_counter/perf_event/g' \
    -e 's/nb_counters/nb_events/g' \
    -e 's/swcounter/swevent/g' \
    -e 's/tpcounter_event/tp_event/g' \
    $FILES

  for N in $(find . -name perf_counter.[ch]); do
    M=$(echo $N | sed 's/perf_counter/perf_event/g')
    mv $N $M
  done

  FILES=$(find . -name perf_event.*)

  sed -i \
    -e 's/COUNTER_MASK/REG_MASK/g' \
    -e 's/COUNTER/EVENT/g' \
    -e 's/\<event\>/event_id/g' \
    -e 's/counter/event/g' \
    -e 's/Counter/Event/g' \
    $FILES

... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.

Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.

( NOTE: 'counters' are still the proper terminology when we deal
  with hardware registers - and these sed scripts are a bit
  over-eager in renaming them. I've undone some of that, but
  in case there's something left where 'counter' would be
  better than 'event' we can undo that on an individual basis
  instead of touching an otherwise nicely automated patch. )
Suggested-by: NStephane Eranian <eranian@google.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NPaul Mackerras <paulus@samba.org>
Reviewed-by: NArjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      cdd6c482
    • I
      perf_counter: Rename 'event' to event_id/hw_event · dfc65094
      由 Ingo Molnar 提交于 
      In preparation to the renames, to avoid a namespace clash.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      dfc65094
    • P
      perf_counter: x86: Fix PMU resource leak · a1792cda
      由 Peter Zijlstra 提交于 
      Dave noticed that we leak the PMU resource reservations when we
fail the hardware counter init.
Reported-by: NDavid Miller <davem@davemloft.net>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NDavid Miller <davem@davemloft.net>
LKML-Reference: <1252483487.7746.164.camel@twins>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a1792cda
  29. 19 9月, 2009 1 次提交
  31. 04 9月, 2009 3 次提交
  33. 12 8月, 2009 1 次提交
    • I
      perf_counter, x86: Fix/improve apic fallback · 04da8a43
      由 Ingo Molnar 提交于 
      Johannes Stezenbach reported that his Pentium-M based
laptop does not have the local APIC enabled by default,
and hence perfcounters do not get initialized.

Add a fallback for this case: allow non-sampled counters
and return with an error on sampled counters. This allows
'perf stat' to work out of box - and allows 'perf top'
and 'perf record' to fall back on a hrtimer based sampling
method.

( Passing 'lapic' on the boot line will allow hardware
  sampling to occur - but if the APIC is disabled
  permanently by the hardware then this fallback still
  allows more systems to use perfcounters. )

Also decouple perfcounter support from X86_LOCAL_APIC.

-v2: fix typo breaking counters on all other systems ...
Reported-by: NJohannes Stezenbach <js@sig21.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      04da8a43
  35. 11 8月, 2009 2 次提交
    • I
      perf_counter, x86: Fix generic cache events on P6-mobile CPUs · f64ccccb
      由 Ingo Molnar 提交于 
      Johannes Stezenbach reported that 'perf stat' does not count
cache-miss and cache-references events on his Pentium-M based
laptop.

This is because we left them blank in p6_perfmon_event_map[],
fill them in.
Reported-by: NJohannes Stezenbach <js@sig21.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      f64ccccb
    • I
      perf_counter, x86: Fix lapic printk message · 3c581a7f
      由 Ingo Molnar 提交于 
      Instead of this garbled bootup on UP Pentium-M systems:

[    0.015048] Performance Counters:
[    0.016004] no Local APIC, try rebooting with lapicno PMU driver, software counters only.

Print:

[    0.015050] Performance Counters:
[    0.016004] no APIC, boot with the "lapic" boot parameter to force-enable it.
[    0.017003] no PMU driver, software counters only.

Cf: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      3c581a7f
  37. 09 8月, 2009 1 次提交
  39. 23 7月, 2009 1 次提交
  41. 13 7月, 2009 1 次提交
    • D
      perf_counter, x86: Extend perf_counter Pentium M support · f1c6a581
      由 Daniel Qarras 提交于 
      I've attached a patch to remove the Pentium M special casing of
EMON and as noticed at least with my Pentium M the hardware PMU
now works:

 Performance counter stats for '/bin/ls /var/tmp':

       1.809988  task-clock-msecs         #      0.125 CPUs
              1  context-switches         #      0.001 M/sec
              0  CPU-migrations           #	 0.000 M/sec
            224  page-faults              #	 0.124 M/sec
        1425648  cycles                   #    787.656 M/sec
         912755  instructions             #	 0.640 IPC

Vince suggested that this code was trying to address erratum
Y17 in Pentium-M's:

  http://download.intel.com/support/processors/mobile/pm/sb/25266532.pdf

But that erratum (related to IA32_MISC_ENABLES.7) does not
affect perfcounters as we dont use this toggle to disable RDPMC
and WRMSR/RDMSR access to performance counters. We keep cr4's
bit 8 (X86_CR4_PCE) clear so unprivileged RDPMC access is not
allowed anyway.

Cc: Vince Weaver <vince@deater.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@googlemail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      f1c6a581
  43. 10 7月, 2009 3 次提交
    • P
      perf_counter: Clean up global vs counter enable · 984b838c
      由 Peter Zijlstra 提交于 
      Ingo noticed that both AMD and P6 call
x86_pmu_disable_counter() on *_pmu_enable_counter(). This is
because we rely on the side effect of that call to program
the event config but not touch the EN bit.

We change that for AMD by having enable_all() simply write
the full config in, and for P6 by explicitly coding it.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      984b838c
    • P
      perf_counter: Fix up P6 PMU details · 9c74fb50
      由 Peter Zijlstra 提交于 
      The P6 doesn't seem to support cache ref/hit/miss counts, so
we extend the generic hardware event codes to have 0 and -1
mean the same thing as for the generic cache events.

Furthermore, it turns out the 0 event does not count
(that is, its reported that on PPro it actually does count
something), therefore use a event configuration that's
specified not to count to disable the counters.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      9c74fb50
    • V
      perf_counter: Add P6 PMU support · 11d1578f
      由 Vince Weaver 提交于 
      Add basic P6 PMU support. The P6 uses the EVNTSEL0 EN bit to
enable/disable both its counters. We use this for the
global enable/disable, and clear all config bits (except EN)
to disable individual counters.

Actual ia32 hardware doesn't support lfence, so use a locked
op without side-effect to implement a full barrier.

perf stat and perf record seem to function correctly.

[a.p.zijlstra@chello.nl: cleanups and complete the enable/disable code]
Signed-off-by: NVince Weaver <vince@deater.net>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <Pine.LNX.4.64.0907081718450.2715@pianoman.cluster.toy>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      11d1578f
  45. 02 7月, 2009 1 次提交
    • F
      perf_counter: Ignore the nmi call frames in the x86-64 backtraces · 0406ca6d
      由 Frederic Weisbecker 提交于 
      About every callchains recorded with perf record are filled up
including the internal perfcounter nmi frame:

 perf_callchain
 perf_counter_overflow
 intel_pmu_handle_irq
 perf_counter_nmi_handler
 notifier_call_chain
 atomic_notifier_call_chain
 notify_die
 do_nmi
 nmi

We want ignore this frame as it's not interesting for
instrumentation. To solve this, we simply ignore every frames
from nmi context.

New example of "perf report -s sym -c" after this patch:

9.59%  [k] search_by_key
             4.88%
                search_by_key
                reiserfs_read_locked_inode
                reiserfs_iget
                reiserfs_lookup
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                vfs_fstatat
                vfs_lstat
                sys_newlstat
                system_call_fastpath
                __lxstat
                0x406fb1

             3.19%
                search_by_key
                search_by_entry_key
                reiserfs_find_entry
                reiserfs_lookup
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                vfs_fstatat
                vfs_lstat
                sys_newlstat
                system_call_fastpath
                __lxstat
                0x406fb1
[...]

For now this patch only solves the problem in x86-64.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246474930-6088-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      0406ca6d
  47. 29 6月, 2009 1 次提交