X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=block%2Fcfq-iosched.c;h=3ad307ee602903e94b500008001359bc40bfebe8;hb=715bb9379e3bb8ed57809406b4f1e27bf6702048;hp=1f9093e901daed7849a54633be5d80ce96b010f4;hpb=9aa3d651a9199103eb6451aeb0ac1b66a6d770a6;p=firefly-linux-kernel-4.4.55.git

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 1f9093e901da..3ad307ee6029 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -3003,7 +3003,6 @@ static struct request *cfq_check_fifo(struct cfq_queue *cfqq)
 	if (time_before(jiffies, rq->fifo_time))
 		rq = NULL;
 
-	cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq);
 	return rq;
 }
 
@@ -3377,6 +3376,9 @@ static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 {
 	unsigned int max_dispatch;
 
+	if (cfq_cfqq_must_dispatch(cfqq))
+		return true;
+
 	/*
 	 * Drain async requests before we start sync IO
 	 */
@@ -3468,15 +3470,20 @@ static bool cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 
 	BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list));
 
+	rq = cfq_check_fifo(cfqq);
+	if (rq)
+		cfq_mark_cfqq_must_dispatch(cfqq);
+
 	if (!cfq_may_dispatch(cfqd, cfqq))
 		return false;
 
 	/*
 	 * follow expired path, else get first next available
 	 */
-	rq = cfq_check_fifo(cfqq);
 	if (!rq)
 		rq = cfqq->next_rq;
+	else
+		cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq);
 
 	/*
 	 * insert request into driver dispatch list
@@ -3944,7 +3951,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
 	 * if the new request is sync, but the currently running queue is
 	 * not, let the sync request have priority.
 	 */
-	if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq))
+	if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq) && !cfq_cfqq_must_dispatch(cfqq))
 		return true;
 
 	if (new_cfqq->cfqg != cfqq->cfqg)