From 6f5ab0019fd328b50a8488c9e5193fc1dbd8d6ed Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Mon, 15 Oct 2012 20:13:45 +0200 Subject: [PATCH] perf: Do not get values from disabled counters in group format read It's possible some of the counters in the group could be disabled when sampling member of the event group is reading the rest via PERF_SAMPLE_READ sample type processing. Disabled counters could then produce wrong numbers. Fixing that by reading only enabled counters for PERF_SAMPLE_READ sample type processing. Signed-off-by: Jiri Olsa Acked-by: Namhyung Kim Acked-by: Peter Zijlstra Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-wwkjb0bbcuslnz0klrmqi26r@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- kernel/events/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 5200b608b481..e82e70025d42 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4388,7 +4388,8 @@ static void perf_output_read_group(struct perf_output_handle *handle, list_for_each_entry(sub, &leader->sibling_list, group_entry) { n = 0; - if (sub != event) + if ((sub != event) && + (sub->state == PERF_EVENT_STATE_ACTIVE)) sub->pmu->read(sub); values[n++] = perf_event_count(sub);