perf: Convert perf_event to local_t

Since now all modification to event->count (and ->prev_count
and ->period_left) are local to a cpu, change then to local64_t so we
avoid the LOCK'ed ops.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 3 insertions, 3 deletions

diff --git a/arch/sh/kernel/perf_event.c b/arch/sh/kernel/perf_event.c
index 81b6de41ae5d..7a3dc3567258 100644
--- a/arch/sh/kernel/perf_event.c
+++ b/arch/sh/kernel/perf_event.c
@@ -185,10 +185,10 @@ static void sh_perf_event_update(struct perf_event *event,
          * this is the simplest approach for maintaining consistency.
          */
 again:
-        prev_raw_count = atomic64_read(&hwc->prev_count);
+        prev_raw_count = local64_read(&hwc->prev_count);
         new_raw_count = sh_pmu->read(idx);
 
-        if (atomic64_cmpxchg(&hwc->prev_count, prev_raw_count,
+        if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
                              new_raw_count) != prev_raw_count)
                 goto again;
 
@@ -203,7 +203,7 @@ again:
         delta = (new_raw_count << shift) - (prev_raw_count << shift);
         delta >>= shift;
 
-        atomic64_add(delta, &event->count);
+        local64_add(delta, &event->count);
 }
 
 static void sh_pmu_disable(struct perf_event *event)