From 59a48cb8e6d41e36dfea100541ac92160ffb80d7 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Tue, 18 May 2010 11:12:48 +0200
Subject: [PATCH] --- yaml --- r: 199096 b: refs/heads/master c:
 6d1acfd5c6bfd5231c13a8f2858d7f2afbaa1b62 h: refs/heads/master v: v3

---
 [refs]                           | 2 +-
 trunk/include/linux/perf_event.h | 1 +
 trunk/kernel/perf_event.c        | 3 ++-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index dda99bb363a0..19a80c26da83 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: fa5881514ef9c9bcb29319aad85cf2d8889d91f1
+refs/heads/master: 6d1acfd5c6bfd5231c13a8f2858d7f2afbaa1b62
diff --git a/trunk/include/linux/perf_event.h b/trunk/include/linux/perf_event.h
index ce7667616fcb..fe50347dc645 100644
--- a/trunk/include/linux/perf_event.h
+++ b/trunk/include/linux/perf_event.h
@@ -804,6 +804,7 @@ struct perf_output_handle {
 	struct perf_mmap_data		*data;
 	unsigned long			head;
 	unsigned long			offset;
+	unsigned long			wakeup;
 	int				nmi;
 	int				sample;
 };
diff --git a/trunk/kernel/perf_event.c b/trunk/kernel/perf_event.c
index 1f98c78c3343..7e3bcf1a29f0 100644
--- a/trunk/kernel/perf_event.c
+++ b/trunk/kernel/perf_event.c
@@ -2917,6 +2917,7 @@ static void perf_output_get_handle(struct perf_output_handle *handle)
 
 	preempt_disable();
 	local_inc(&data->nest);
+	handle->wakeup = local_read(&data->wakeup);
 }
 
 static void perf_output_put_handle(struct perf_output_handle *handle)
@@ -2950,7 +2951,7 @@ static void perf_output_put_handle(struct perf_output_handle *handle)
 		goto again;
 	}
 
-	if (local_xchg(&data->wakeup, 0))
+	if (handle->wakeup != local_read(&data->wakeup))
 		perf_output_wakeup(handle);
 
 	preempt_enable();