linux/arch/x86
Cyrill Gorcunov 137351e0fe x86, perf: P4 PMU -- protect sensible procedures from preemption
Steven reported:

|
| I'm getting:
|
| Pid: 3477, comm: perf Not tainted 2.6.34-rc6 #2727
| Call Trace:
|  [<ffffffff811c7565>] debug_smp_processor_id+0xd5/0xf0
|  [<ffffffff81019874>] p4_hw_config+0x2b/0x15c
|  [<ffffffff8107acbc>] ? trace_hardirqs_on_caller+0x12b/0x14f
|  [<ffffffff81019143>] hw_perf_event_init+0x468/0x7be
|  [<ffffffff810782fd>] ? debug_mutex_init+0x31/0x3c
|  [<ffffffff810c68b2>] T.850+0x273/0x42e
|  [<ffffffff810c6cab>] sys_perf_event_open+0x23e/0x3f1
|  [<ffffffff81009e6a>] ? sysret_check+0x2e/0x69
|  [<ffffffff81009e32>] system_call_fastpath+0x16/0x1b
|
| When running perf record in latest tip/perf/core
|

Due to the fact that p4 counters are shared between HT threads
we synthetically divide the whole set of counters into two
non-intersected subsets. And while we're "borrowing" counters
from these subsets we should not be preempted (well, strictly
speaking in p4_hw_config we just pre-set reference to the
subset which allow to save some cycles in schedule routine
if it happens on the same cpu). So use get_cpu/put_cpu pair.

Also p4_pmu_schedule_events should use smp_processor_id rather
than raw_ version. This allow us to catch up preemption issue
(if there will ever be).

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <20100508112716.963478928@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-08 14:17:53 +02:00
..
boot Merge branch 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-28 10:43:53 -08:00
configs
crypto include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
ia32 x86: correctly wire up the newuname system call 2010-04-20 09:17:21 -07:00
include/asm Merge branch 'perf/urgent' into perf/core 2010-05-07 11:30:30 +02:00
kernel x86, perf: P4 PMU -- protect sensible procedures from preemption 2010-05-08 14:17:53 +02:00
kvm Merge branch 'linus' into perf/core 2010-04-23 11:10:30 +02:00
lguest lguest: stop using KVM hypercall mechanism 2010-04-14 21:43:56 +09:30
lib Merge branch 'perf/urgent' into perf/core 2010-05-07 11:30:30 +02:00
math-emu
mm x86: Fix parse_reservetop() build failure on certain configs 2010-05-03 09:22:19 +02:00
oprofile perf, x86: Undo some some *_counter* -> *_event* renames 2010-04-02 19:52:02 +02:00
pci x86/PCI: compute Address Space length rather than using _LEN 2010-04-28 09:17:45 -07:00
power Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip 2010-04-07 11:02:23 -07:00
tools x86: Remove trailing spaces in messages 2010-02-07 17:47:51 +01:00
vdso include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
video
xen include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
Kbuild
Kconfig hw-breakpoints: Separate constraint space for data and instruction breakpoints 2010-05-01 04:32:11 +02:00
Kconfig.cpu x86, perf, bts, mm: Delete the never used BTS-ptrace code 2010-03-26 11:33:55 +01:00
Kconfig.debug x86, perf, bts, mm: Delete the never used BTS-ptrace code 2010-03-26 11:33:55 +01:00
Makefile x86-64: Allow fbdev primary video code 2010-02-16 21:22:26 -08:00
Makefile_32.cpu Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-12-08 13:38:11 -08:00