[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>

fs/ext2/xattr.c

@@ -342,12 +342,9 @@ static void ext2_xattr_update_super_block(struct super_block *sb)
 	if (EXT2_HAS_COMPAT_FEATURE(sb, EXT2_FEATURE_COMPAT_EXT_ATTR))
 		return;
 
-	lock_super(sb);
-	EXT2_SB(sb)->s_es->s_feature_compat |=
-		cpu_to_le32(EXT2_FEATURE_COMPAT_EXT_ATTR);
+	EXT2_SET_COMPAT_FEATURE(sb, EXT2_FEATURE_COMPAT_EXT_ATTR);
 	sb->s_dirt = 1;
 	mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
-	unlock_super(sb);
 }
 
 /*