diff options
| -rw-r--r-- | block/blk-core.c | 8 | ||||
| -rw-r--r-- | block/cfq-iosched.c | 56 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 4 |
3 files changed, 48 insertions, 20 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index ddaaea4fdff..a8c7fbe52e2 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2492,6 +2492,14 @@ int kblockd_schedule_work(struct request_queue *q, struct work_struct *work) } EXPORT_SYMBOL(kblockd_schedule_work); +int kblockd_schedule_delayed_work(struct request_queue *q, + struct delayed_work *work, + unsigned long delay) +{ + return queue_delayed_work(kblockd_workqueue, work, delay); +} +EXPORT_SYMBOL(kblockd_schedule_delayed_work); + int __init blk_dev_init(void) { BUILD_BUG_ON(__REQ_NR_BITS > 8 * diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 70b48ea0e3e..fce8a749f4b 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -150,7 +150,7 @@ struct cfq_data { * idle window management */ struct timer_list idle_slice_timer; - struct work_struct unplug_work; + struct delayed_work unplug_work; struct cfq_queue *active_queue; struct cfq_io_context *active_cic; @@ -268,11 +268,13 @@ static inline int cfq_bio_sync(struct bio *bio) * scheduler run of queue, if there are requests pending and no one in the * driver that will restart queueing */ -static inline void cfq_schedule_dispatch(struct cfq_data *cfqd) +static inline void cfq_schedule_dispatch(struct cfq_data *cfqd, + unsigned long delay) { if (cfqd->busy_queues) { cfq_log(cfqd, "schedule dispatch"); - kblockd_schedule_work(cfqd->queue, &cfqd->unplug_work); + kblockd_schedule_delayed_work(cfqd->queue, &cfqd->unplug_work, + delay); } } @@ -1316,8 +1318,6 @@ static int cfq_dispatch_requests(struct request_queue *q, int force) * Does this cfqq already have too much IO in flight? */ if (cfqq->dispatched >= max_dispatch) { - unsigned long load_at = cfqd->last_end_sync_rq + cfq_slice_sync; - /* * idle queue must always only have a single IO in flight */ @@ -1331,20 +1331,36 @@ static int cfq_dispatch_requests(struct request_queue *q, int force) return 0; /* - * If a sync request has completed recently, don't overload - * the dispatch queue yet with async requests. + * Sole queue user, allow bigger slice */ - if (cfqd->cfq_desktop && !cfq_cfqq_sync(cfqq) - && time_before(jiffies, load_at)) - return 0; + max_dispatch *= 4; + } + + /* + * Async queues must wait a bit before being allowed dispatch. + * We also ramp up the dispatch depth gradually for async IO, + * based on the last sync IO we serviced + */ + if (!cfq_cfqq_sync(cfqq) && cfqd->cfq_desktop) { + unsigned long last_sync = jiffies - cfqd->last_end_sync_rq; + unsigned int depth; /* - * we are the only queue, allow up to 4 times of 'quantum' + * must wait a bit longer */ - if (cfqq->dispatched >= 4 * max_dispatch) + if (last_sync < cfq_slice_sync) { + cfq_schedule_dispatch(cfqd, cfq_slice_sync - last_sync); return 0; + } + + depth = last_sync / cfq_slice_sync; + if (depth < max_dispatch) + max_dispatch = depth; } + if (cfqq->dispatched >= max_dispatch) + return 0; + /* * Dispatch a request from this cfqq */ @@ -1389,7 +1405,7 @@ static void cfq_put_queue(struct cfq_queue *cfqq) if (unlikely(cfqd->active_queue == cfqq)) { __cfq_slice_expired(cfqd, cfqq, 0); - cfq_schedule_dispatch(cfqd); + cfq_schedule_dispatch(cfqd, 0); } kmem_cache_free(cfq_pool, cfqq); @@ -1484,7 +1500,7 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) { if (unlikely(cfqq == cfqd->active_queue)) { __cfq_slice_expired(cfqd, cfqq, 0); - cfq_schedule_dispatch(cfqd); + cfq_schedule_dispatch(cfqd, 0); } cfq_put_queue(cfqq); @@ -2201,7 +2217,7 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq) } if (!rq_in_driver(cfqd)) - cfq_schedule_dispatch(cfqd); + cfq_schedule_dispatch(cfqd, 0); } /* @@ -2331,7 +2347,7 @@ queue_fail: if (cic) put_io_context(cic->ioc); - cfq_schedule_dispatch(cfqd); + cfq_schedule_dispatch(cfqd, 0); spin_unlock_irqrestore(q->queue_lock, flags); cfq_log(cfqd, "set_request fail"); return 1; @@ -2340,7 +2356,7 @@ queue_fail: static void cfq_kick_queue(struct work_struct *work) { struct cfq_data *cfqd = - container_of(work, struct cfq_data, unplug_work); + container_of(work, struct cfq_data, unplug_work.work); struct request_queue *q = cfqd->queue; spin_lock_irq(q->queue_lock); @@ -2394,7 +2410,7 @@ static void cfq_idle_slice_timer(unsigned long data) expire: cfq_slice_expired(cfqd, timed_out); out_kick: - cfq_schedule_dispatch(cfqd); + cfq_schedule_dispatch(cfqd, 0); out_cont: spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); } @@ -2402,7 +2418,7 @@ out_cont: static void cfq_shutdown_timer_wq(struct cfq_data *cfqd) { del_timer_sync(&cfqd->idle_slice_timer); - cancel_work_sync(&cfqd->unplug_work); + cancel_delayed_work_sync(&cfqd->unplug_work); } static void cfq_put_async_queues(struct cfq_data *cfqd) @@ -2484,7 +2500,7 @@ static void *cfq_init_queue(struct request_queue *q) cfqd->idle_slice_timer.function = cfq_idle_slice_timer; cfqd->idle_slice_timer.data = (unsigned long) cfqd; - INIT_WORK(&cfqd->unplug_work, cfq_kick_queue); + INIT_DELAYED_WORK(&cfqd->unplug_work, cfq_kick_queue); cfqd->cfq_quantum = cfq_quantum; cfqd->cfq_fifo_expire[0] = cfq_fifo_expire[0]; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 1a03b715dfa..a7323930d2b 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1147,7 +1147,11 @@ static inline void put_dev_sector(Sector p) } struct work_struct; +struct delayed_work; int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); +int kblockd_schedule_delayed_work(struct request_queue *q, + struct delayed_work *work, + unsigned long delay); #define MODULE_ALIAS_BLOCKDEV(major,minor) \ MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) |