diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/cfq-iosched.c | 46 |
1 files changed, 25 insertions, 21 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index b6491c020f26..f92ba2a869b4 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -532,6 +532,12 @@ static void cfq_add_rq_rb(struct request *rq) if (!cfq_cfqq_on_rr(cfqq)) cfq_add_cfqq_rr(cfqd, cfqq); + + /* + * check if this request is a better next-serve candidate + */ + cfqq->next_rq = cfq_choose_req(cfqd, cfqq->next_rq, rq); + BUG_ON(!cfqq->next_rq); } static inline void @@ -986,9 +992,9 @@ __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 +1057,21 @@ 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 +1378,9 @@ retry: 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); @@ -1635,12 +1645,6 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, cfqq->meta_pending++; /* - * check if this request is a better next-serve candidate)) { - */ - cfqq->next_rq = cfq_choose_req(cfqd, cfqq->next_rq, rq); - BUG_ON(!cfqq->next_rq); - - /* * we never wait for an async request and we don't allow preemption * of an async request. so just return early */ |