[tip:perf/core] perf: Ignore non-sampling overflows

[tip-bot for Peter Zijlstra]

Commit-ID:  963988262c3c8f4234f64a0dde59446a295e07bb
Gitweb:     http://git.kernel.org/tip/963988262c3c8f4234f64a0dde59446a295e07bb
Author:     Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
AuthorDate: Wed, 24 Nov 2010 18:55:29 +0100
Committer:  Ingo Molnar <mingo@xxxxxxx>
CommitDate: Fri, 26 Nov 2010 15:14:55 +0100

perf: Ignore non-sampling overflows

Some arch implementations call perf_event_overflow() by 'accident',
ignore this.

Reported-by: Francis Moreau <francis.moro@xxxxxxxxx>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
 kernel/perf_event.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 98c5549..af1e63f 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4240,6 +4240,13 @@ static int __perf_event_overflow(struct perf_event *event, int nmi,
 	struct hw_perf_event *hwc = &event->hw;
 	int ret = 0;
 
+	/*
+	 * Non-sampling counters might still use the PMI to fold short
+	 * hardware counters, ignore those.
+	 */
+	if (unlikely(!is_sampling_event(event)))
+		return 0;
+
 	if (!throttle) {
 		hwc->interrupts++;
 	} else {
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/