[tip:perf/urgent] perf/x86/intel: Allow PEBS multi-entry in watermark mode

From: tip-bot for Stephane Eranian
Date: Tue May 14 2019 - 03:15:01 EST


Commit-ID: c7a286577d7592720c2f179aadfb325a1ff48c95
Gitweb: https://git.kernel.org/tip/c7a286577d7592720c2f179aadfb325a1ff48c95
Author: Stephane Eranian <eranian@xxxxxxxxxx>
AuthorDate: Mon, 13 May 2019 17:34:00 -0700
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 14 May 2019 09:07:58 +0200

perf/x86/intel: Allow PEBS multi-entry in watermark mode

This patch fixes a restriction/bug introduced by:

583feb08e7f7 ("perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS")

The original patch prevented using multi-entry PEBS when wakeup_events != 0.
However given that wakeup_events is part of a union with wakeup_watermark, it
means that in watermark mode, PEBS multi-entry is also disabled which is not the
intent. This patch fixes this by checking is watermark mode is enabled.

Signed-off-by: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: jolsa@xxxxxxxxxx
Cc: kan.liang@xxxxxxxxx
Cc: vincent.weaver@xxxxxxxxx
Fixes: 583feb08e7f7 ("perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS")
Link: http://lkml.kernel.org/r/20190514003400.224340-1-eranian@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/events/intel/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index ef763f535e3a..12ec402f4114 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3265,7 +3265,7 @@ static int intel_pmu_hw_config(struct perf_event *event)
return ret;

if (event->attr.precise_ip) {
- if (!(event->attr.freq || event->attr.wakeup_events)) {
+ 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)))