diff options
| author | Kan Liang <kan.liang@linux.intel.com> | 2020-11-30 22:38:41 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2021-03-06 14:52:44 +0300 |
| commit | afbef30149587ad46f4780b1e0cc5e219745ce90 (patch) | |
| tree | 8ce1c9c814944c1d19a8bd10b19108ab2540822a /arch/x86 | |
| parent | a5398bffc01fe044848c5024e5e867e407f239b8 (diff) | |
| download | linux-afbef30149587ad46f4780b1e0cc5e219745ce90.tar.xz | |
perf/x86/intel: Set PERF_ATTACH_SCHED_CB for large PEBS and LBR
To supply a PID/TID for large PEBS, it requires flushing the PEBS buffer
in a context switch.
For normal LBRs, a context switch can flip the address space and LBR
entries are not tagged with an identifier, we need to wipe the LBR, even
for per-cpu events.
For LBR callstack, save/restore the stack is required during a context
switch.
Set PERF_ATTACH_SCHED_CB for the event with large PEBS & LBR.
Fixes: 9c964efa4330 ("perf/x86/intel: Drain the PEBS buffer during context switches")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20201130193842.10569-2-kan.liang@linux.intel.com
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/events/intel/core.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 5bac48d5c18e..7bbb5bb98d8c 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3662,8 +3662,10 @@ static int intel_pmu_hw_config(struct perf_event *event) if (!(event->attr.freq || (event->attr.wakeup_events && !event->attr.watermark))) { event->hw.flags |= PERF_X86_EVENT_AUTO_RELOAD; if (!(event->attr.sample_type & - ~intel_pmu_large_pebs_flags(event))) + ~intel_pmu_large_pebs_flags(event))) { event->hw.flags |= PERF_X86_EVENT_LARGE_PEBS; + event->attach_state |= PERF_ATTACH_SCHED_CB; + } } if (x86_pmu.pebs_aliases) x86_pmu.pebs_aliases(event); @@ -3676,6 +3678,7 @@ static int intel_pmu_hw_config(struct perf_event *event) ret = intel_pmu_setup_lbr_filter(event); if (ret) return ret; + event->attach_state |= PERF_ATTACH_SCHED_CB; /* * BTS is set up earlier in this path, so don't account twice |