perf/x86/intel: Allow PEBS multi-entry in watermark mode
authorStephane Eranian <eranian@google.com>
Tue, 14 May 2019 00:34:00 +0000 (17:34 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 22 Jun 2019 06:17:13 +0000 (08:17 +0200)
[ Upstream commit c7a286577d7592720c2f179aadfb325a1ff48c95 ]

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@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jolsa@redhat.com
Cc: kan.liang@intel.com
Cc: vincent.weaver@maine.edu
Fixes: 583feb08e7f7 ("perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS")
Link: http://lkml.kernel.org/r/20190514003400.224340-1-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arch/x86/events/intel/core.c

index cb8178a..e98e238 100644 (file)
@@ -2867,7 +2867,7 @@ 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_free_running_flags(event)))