summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorKan Liang <kan.liang@linux.intel.com>2020-11-30 22:38:41 +0300
committerIngo Molnar <mingo@kernel.org>2021-03-06 14:52:44 +0300
commitafbef30149587ad46f4780b1e0cc5e219745ce90 (patch)
tree8ce1c9c814944c1d19a8bd10b19108ab2540822a /arch
parenta5398bffc01fe044848c5024e5e867e407f239b8 (diff)
downloadlinux-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')
-rw-r--r--arch/x86/events/intel/core.c5
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