diff --git a/[refs] b/[refs]
index a9b840739b50..c97f37ebc847 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 52494535103986dbbf689b44d8c2c7efe2132b16
+refs/heads/master: 7e8b1e78ea028cbd32337e2aea574a8466c796bb
diff --git a/trunk/Documentation/atomic_ops.txt b/trunk/Documentation/atomic_ops.txt
index 27f2b21a9d5c..d9ca5be9b471 100644
--- a/trunk/Documentation/atomic_ops.txt
+++ b/trunk/Documentation/atomic_ops.txt
@@ -253,6 +253,8 @@ This performs an atomic exchange operation on the atomic variable v, setting
 the given new value.  It returns the old value that the atomic variable v had
 just before the operation.
 
+atomic_xchg requires explicit memory barriers around the operation.
+
 	int atomic_cmpxchg(atomic_t *v, int old, int new);
 
 This performs an atomic compare exchange operation on the atomic value v,
diff --git a/trunk/Documentation/memory-barriers.txt b/trunk/Documentation/memory-barriers.txt
index 3c4e1b3b80a1..fa5d8a9ae205 100644
--- a/trunk/Documentation/memory-barriers.txt
+++ b/trunk/Documentation/memory-barriers.txt
@@ -1685,6 +1685,7 @@ explicit lock operations, described later).  These include:
 
 	xchg();
 	cmpxchg();
+	atomic_xchg();
 	atomic_cmpxchg();
 	atomic_inc_return();
 	atomic_dec_return();