diff --git a/[refs] b/[refs]
index 62913033a800..7627284c5838 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7667aa0630407bc07dc38dcc79d29cc0a65553c1
+refs/heads/master: edc71131c4dc6cc73e2a24aa0a7a79cfce738f12
diff --git a/trunk/block/cfq-iosched.c b/trunk/block/cfq-iosched.c
index 98b15b98b85d..69ecee7f4ad4 100644
--- a/trunk/block/cfq-iosched.c
+++ b/trunk/block/cfq-iosched.c
@@ -3759,6 +3759,10 @@ static void *cfq_init_queue(struct request_queue *q)
 	cfqd->cfq_latency = 1;
 	cfqd->cfq_group_isolation = 0;
 	cfqd->hw_tag = -1;
+	/*
+	 * we optimistically start assuming sync ops weren't delayed in last
+	 * second, in order to have larger depth for async operations.
+	 */
 	cfqd->last_delayed_sync = jiffies - HZ;
 	INIT_RCU_HEAD(&cfqd->rcu);
 	return cfqd;