[PATCH v3 14/15] perf: Identify the 0->1 transition for event::mmap_count

[Peter Zijlstra]

Needed because refcount_inc() doesn't allow the 0->1 transition.

Suggested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 kernel/events/core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7033,7 +7033,7 @@ static int perf_mmap_rb(struct vm_area_s
 	perf_event_update_userpage(event);
 
 	perf_mmap_account(vma, user_extra, extra);
-	atomic_inc(&event->mmap_count);
+	atomic_set(&event->mmap_count, 1);
 
 	return 0;
 }