diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index b6491c020f26..9e3797167c81 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -986,9 +986,9 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq, * expire an async queue immediately if it has used up its slice. idle * queue always expire after 1 dispatch round. */ - if ((!cfq_cfqq_sync(cfqq) && + if (cfqd->busy_queues > 1 && ((!cfq_cfqq_sync(cfqq) && cfqd->dispatch_slice >= cfq_prio_to_maxrq(cfqd, cfqq)) || - cfq_class_idle(cfqq)) { + cfq_class_idle(cfqq))) { cfqq->slice_end = jiffies + 1; cfq_slice_expired(cfqd, 0, 0); } @@ -1051,19 +1051,21 @@ cfq_dispatch_requests(request_queue_t *q, int force) while ((cfqq = cfq_select_queue(cfqd)) != NULL) { int max_dispatch; - /* - * Don't repeat dispatch from the previous queue. - */ - if (prev_cfqq == cfqq) - break; + if (cfqd->busy_queues > 1) { + /* + * Don't repeat dispatch from the previous queue. + */ + if (prev_cfqq == cfqq) + break; - /* - * So we have dispatched before in this round, if the - * next queue has idling enabled (must be sync), don't - * allow it service until the previous have continued. - */ - if (cfqd->rq_in_driver && cfq_cfqq_idle_window(cfqq)) - break; + /* + * So we have dispatched before in this round, if the + * next queue has idling enabled (must be sync), don't + * allow it service until the previous have continued. + */ + if (cfqd->rq_in_driver && cfq_cfqq_idle_window(cfqq)) + break; + } cfq_clear_cfqq_must_dispatch(cfqq); cfq_clear_cfqq_wait_request(cfqq); @@ -1370,7 +1372,9 @@ cfq_get_queue(struct cfq_data *cfqd, unsigned int key, struct task_struct *tsk, atomic_set(&cfqq->ref, 0); cfqq->cfqd = cfqd; - cfq_mark_cfqq_idle_window(cfqq); + if (key != CFQ_KEY_ASYNC) + cfq_mark_cfqq_idle_window(cfqq); + cfq_mark_cfqq_prio_changed(cfqq); cfq_mark_cfqq_queue_new(cfqq); cfq_init_prio_data(cfqq);