[PATCH] Remove superfluous lock_super() in extN xattr code

lock_super() is unnecessary for setting super-block feature flags.  Use the
provided *_SET_COMPAT_FEATURE() macros as well.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 63233cd..dc969c3 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -459,14 +459,11 @@
 	if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR))
 		return;
 
-	lock_super(sb);
 	if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) {
-		EXT4_SB(sb)->s_es->s_feature_compat |=
-			cpu_to_le32(EXT4_FEATURE_COMPAT_EXT_ATTR);
+		EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR);
 		sb->s_dirt = 1;
 		ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
 	}
-	unlock_super(sb);
 }
 
 /*