From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bob Peterson <rpeterso@redhat.com>
Date: Thu, 25 Jul 2013 09:53:49 -0400 (EDT)
Subject: [Cluster-devel] [GFS2 PATCH] GFS2: Remove unnecessary memory barrier
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Hi,

Function test_and_clear_bit implies a memory barrier, so subsequent
memory barriers are unnecessary.

Regards,

Bob Peterson
Red Hat File Systems

Signed-off-by: Bob Peterson <rpeterso@redhat.com> 
---
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 9435384..a45b1e0 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1411,7 +1411,6 @@ __acquires(&lru_lock)
 		if (demote_ok(gl))
 			handle_callback(gl, LM_ST_UNLOCKED, 0, false);
 		WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
-		smp_mb__after_clear_bit();
 		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
 			gfs2_glock_put_nolock(gl);
 		spin_unlock(&gl->gl_spin);