perf: Simplify __perf_event_sync_stat

Removes constraints from __perf_event_read() by leaving it with
a single callsite; this callsite had ctx->lock held, the other
one does not.

Removes some superfluous code from __perf_event_sync_stat().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.918544317@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 4 deletions

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index e66f6c400d13..af150bbcfc5b 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1061,8 +1061,6 @@ static int context_equiv(struct perf_event_context *ctx1,
                 && !ctx1->pin_count && !ctx2->pin_count;
 }
 
-static void __perf_event_read(void *event);
-
 static void __perf_event_sync_stat(struct perf_event *event,
                                      struct perf_event *next_event)
 {
@@ -1080,8 +1078,8 @@ static void __perf_event_sync_stat(struct perf_event *event,
          */
         switch (event->state) {
         case PERF_EVENT_STATE_ACTIVE:
-                __perf_event_read(event);
-                break;
+                event->pmu->read(event);
+                /* fall-through */
 
         case PERF_EVENT_STATE_INACTIVE:
                 update_event_times(event);