[Cluster-devel] [PATCH 2/6] GFS2: use memchr_inv

[Steven Whitehouse]

From: Akinobu Mita <akinobu.mita at gmail.com>

Use memchr_inv to verify that the specified memory range is cleared.

Signed-off-by: Akinobu Mita <akinobu.mita at gmail.com>
Cc: Steven Whitehouse <swhiteho at redhat.com>
Cc: cluster-devel at redhat.com
Cc: Christine Caulfield <ccaulfie at redhat.com>
Cc: David Teigland <teigland at redhat.com>

diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c
index b15bb45..c8423d6 100644
--- a/fs/gfs2/lock_dlm.c
+++ b/fs/gfs2/lock_dlm.c
@@ -483,12 +483,8 @@ static void control_lvb_write(struct lm_lockstruct *ls, uint32_t lvb_gen,
 
 static int all_jid_bits_clear(char *lvb)
 {
-	int i;
-	for (i = JID_BITMAP_OFFSET; i < GDLM_LVB_SIZE; i++) {
-		if (lvb[i])
-			return 0;
-	}
-	return 1;
+	return !memchr_inv(lvb + JID_BITMAP_OFFSET, 0,
+			GDLM_LVB_SIZE - JID_BITMAP_OFFSET);
 }
 
 static void sync_wait_cb(void *arg)
-- 
1.7.4