perf: Handle stopped state with tracepoints

commit a0f7d0f7fc02465bb9758501f611f63381792996 upstream.

We toggle the state from start and stop callbacks but actually
don't check it when the event triggers. Do it so that
these callbacks actually work.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299529629-18280-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 183d437f4a0fb7c5ad96ad82ae3f6d28333e52e1..f9af60f30adfb5dc245c85227f20b7cd1cc83d1a 100644 (file)
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4167,6 +4167,8 @@ static void tp_perf_event_destroy(struct perf_event *event)
 
 static const struct pmu *tp_perf_event_init(struct perf_event *event)
 {
+       if (event->hw.state & PERF_HES_STOPPED)
+               return 0;
        /*
         * Raw tracepoint data is a severe data leak, only allow root to
         * have these.