diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/as-iosched.c | 13 | ||||
| -rw-r--r-- | block/cfq-iosched.c | 62 | ||||
| -rw-r--r-- | block/deadline-iosched.c | 13 | ||||
| -rw-r--r-- | block/elevator.c | 55 | ||||
| -rw-r--r-- | block/noop-iosched.c | 7 |
5 files changed, 94 insertions, 56 deletions
diff --git a/block/as-iosched.c b/block/as-iosched.c index e25a5d79ab27..a7caf35ca0c2 100644 --- a/block/as-iosched.c +++ b/block/as-iosched.c @@ -1648,17 +1648,17 @@ static void as_exit_queue(elevator_t *e) * initialize elevator private data (as_data), and alloc a arq for * each request on the free lists */ -static int as_init_queue(request_queue_t *q, elevator_t *e) +static void *as_init_queue(request_queue_t *q, elevator_t *e) { struct as_data *ad; int i; if (!arq_pool) - return -ENOMEM; + return NULL; ad = kmalloc_node(sizeof(*ad), GFP_KERNEL, q->node); if (!ad) - return -ENOMEM; + return NULL; memset(ad, 0, sizeof(*ad)); ad->q = q; /* Identify what queue the data belongs to */ @@ -1667,7 +1667,7 @@ static int as_init_queue(request_queue_t *q, elevator_t *e) GFP_KERNEL, q->node); if (!ad->hash) { kfree(ad); - return -ENOMEM; + return NULL; } ad->arq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab, @@ -1675,7 +1675,7 @@ static int as_init_queue(request_queue_t *q, elevator_t *e) if (!ad->arq_pool) { kfree(ad->hash); kfree(ad); - return -ENOMEM; + return NULL; } /* anticipatory scheduling helpers */ @@ -1696,14 +1696,13 @@ static int as_init_queue(request_queue_t *q, elevator_t *e) ad->antic_expire = default_antic_expire; ad->batch_expire[REQ_SYNC] = default_read_batch_expire; ad->batch_expire[REQ_ASYNC] = default_write_batch_expire; - e->elevator_data = ad; ad->current_batch_expires = jiffies + ad->batch_expire[REQ_SYNC]; ad->write_batch_count = ad->batch_expire[REQ_ASYNC] / 10; if (ad->write_batch_count < 2) ad->write_batch_count = 2; - return 0; + return ad; } /* diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 11ce6aaf1bd0..a46d030e092a 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -133,6 +133,7 @@ struct cfq_data { mempool_t *crq_pool; int rq_in_driver; + int hw_tag; /* * schedule slice state info @@ -500,10 +501,13 @@ static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted) /* * if queue was preempted, just add to front to be fair. busy_rr - * isn't sorted. + * isn't sorted, but insert at the back for fairness. */ if (preempted || list == &cfqd->busy_rr) { - list_add(&cfqq->cfq_list, list); + if (preempted) + list = list->prev; + + list_add_tail(&cfqq->cfq_list, list); return; } @@ -664,6 +668,15 @@ static void cfq_activate_request(request_queue_t *q, struct request *rq) struct cfq_data *cfqd = q->elevator->elevator_data; cfqd->rq_in_driver++; + + /* + * If the depth is larger 1, it really could be queueing. But lets + * make the mark a little higher - idling could still be good for + * low queueing, and a low queueing number could also just indicate + * a SCSI mid layer like behaviour where limit+1 is often seen. + */ + if (!cfqd->hw_tag && cfqd->rq_in_driver > 4) + cfqd->hw_tag = 1; } static void cfq_deactivate_request(request_queue_t *q, struct request *rq) @@ -879,6 +892,13 @@ static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd) cfqq = list_entry_cfqq(cfqd->cur_rr.next); /* + * If no new queues are available, check if the busy list has some + * before falling back to idle io. + */ + if (!cfqq && !list_empty(&cfqd->busy_rr)) + cfqq = list_entry_cfqq(cfqd->busy_rr.next); + + /* * if we have idle queues and no rt or be queues had pending * requests, either allow immediate service if the grace period * has passed or arm the idle grace timer @@ -1458,7 +1478,8 @@ retry: * set ->slice_left to allow preemption for a new process */ cfqq->slice_left = 2 * cfqd->cfq_slice_idle; - cfq_mark_cfqq_idle_window(cfqq); + if (!cfqd->hw_tag) + cfq_mark_cfqq_idle_window(cfqq); cfq_mark_cfqq_prio_changed(cfqq); cfq_init_prio_data(cfqq); } @@ -1649,7 +1670,7 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, { int enable_idle = cfq_cfqq_idle_window(cfqq); - if (!cic->ioc->task || !cfqd->cfq_slice_idle) + if (!cic->ioc->task || !cfqd->cfq_slice_idle || cfqd->hw_tag) enable_idle = 0; else if (sample_valid(cic->ttime_samples)) { if (cic->ttime_mean > cfqd->cfq_slice_idle) @@ -1740,14 +1761,24 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, cfqq->next_crq = cfq_choose_req(cfqd, cfqq->next_crq, crq); + cic = crq->io_context; + /* * we never wait for an async request and we don't allow preemption * of an async request. so just return early */ - if (!cfq_crq_is_sync(crq)) + if (!cfq_crq_is_sync(crq)) { + /* + * sync process issued an async request, if it's waiting + * then expire it and kick rq handling. + */ + if (cic == cfqd->active_cic && + del_timer(&cfqd->idle_slice_timer)) { + cfq_slice_expired(cfqd, 0); + cfq_start_queueing(cfqd, cfqq); + } return; - - cic = crq->io_context; + } cfq_update_io_thinktime(cfqd, cic); cfq_update_io_seektime(cfqd, cic, crq); @@ -2165,10 +2196,9 @@ static void cfq_idle_class_timer(unsigned long data) * race with a non-idle queue, reset timer */ end = cfqd->last_end_request + CFQ_IDLE_GRACE; - if (!time_after_eq(jiffies, end)) { - cfqd->idle_class_timer.expires = end; - add_timer(&cfqd->idle_class_timer); - } else + if (!time_after_eq(jiffies, end)) + mod_timer(&cfqd->idle_class_timer, end); + else cfq_schedule_dispatch(cfqd); spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); @@ -2221,14 +2251,14 @@ static void cfq_exit_queue(elevator_t *e) kfree(cfqd); } -static int cfq_init_queue(request_queue_t *q, elevator_t *e) +static void *cfq_init_queue(request_queue_t *q, elevator_t *e) { struct cfq_data *cfqd; int i; cfqd = kmalloc(sizeof(*cfqd), GFP_KERNEL); if (!cfqd) - return -ENOMEM; + return NULL; memset(cfqd, 0, sizeof(*cfqd)); @@ -2258,8 +2288,6 @@ static int cfq_init_queue(request_queue_t *q, elevator_t *e) for (i = 0; i < CFQ_QHASH_ENTRIES; i++) INIT_HLIST_HEAD(&cfqd->cfq_hash[i]); - e->elevator_data = cfqd; - cfqd->queue = q; cfqd->max_queued = q->nr_requests / 4; @@ -2286,14 +2314,14 @@ static int cfq_init_queue(request_queue_t *q, elevator_t *e) cfqd->cfq_slice_async_rq = cfq_slice_async_rq; cfqd->cfq_slice_idle = cfq_slice_idle; - return 0; + return cfqd; out_crqpool: kfree(cfqd->cfq_hash); out_cfqhash: kfree(cfqd->crq_hash); out_crqhash: kfree(cfqd); - return -ENOMEM; + return NULL; } static void cfq_slab_kill(void) diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c index 399fa1e60e1f..3bd0415a9828 100644 --- a/block/deadline-iosched.c +++ b/block/deadline-iosched.c @@ -613,24 +613,24 @@ static void deadline_exit_queue(elevator_t *e) * initialize elevator private data (deadline_data), and alloc a drq for * each request on the free lists */ -static int deadline_init_queue(request_queue_t *q, elevator_t *e) +static void *deadline_init_queue(request_queue_t *q, elevator_t *e) { struct deadline_data *dd; int i; if (!drq_pool) - return -ENOMEM; + return NULL; dd = kmalloc_node(sizeof(*dd), GFP_KERNEL, q->node); if (!dd) - return -ENOMEM; + return NULL; memset(dd, 0, sizeof(*dd)); dd->hash = kmalloc_node(sizeof(struct list_head)*DL_HASH_ENTRIES, GFP_KERNEL, q->node); if (!dd->hash) { kfree(dd); - return -ENOMEM; + return NULL; } dd->drq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab, @@ -638,7 +638,7 @@ static int deadline_init_queue(request_queue_t *q, elevator_t *e) if (!dd->drq_pool) { kfree(dd->hash); kfree(dd); - return -ENOMEM; + return NULL; } for (i = 0; i < DL_HASH_ENTRIES; i++) @@ -653,8 +653,7 @@ static int deadline_init_queue(request_queue_t *q, elevator_t *e) dd->writes_starved = writes_starved; dd->front_merges = 1; dd->fifo_batch = fifo_batch; - e->elevator_data = dd; - return 0; + return dd; } static void deadline_put_request(request_queue_t *q, struct request *rq) diff --git a/block/elevator.c b/block/elevator.c index 8768a367fdde..a0afdd317cef 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -121,16 +121,16 @@ static struct elevator_type *elevator_get(const char *name) return e; } -static int elevator_attach(request_queue_t *q, struct elevator_queue *eq) +static void *elevator_init_queue(request_queue_t *q, struct elevator_queue *eq) { - int ret = 0; + return eq->ops->elevator_init_fn(q, eq); +} +static void elevator_attach(request_queue_t *q, struct elevator_queue *eq, + void *data) +{ q->elevator = eq; - - if (eq->ops->elevator_init_fn) - ret = eq->ops->elevator_init_fn(q, eq); - - return ret; + eq->elevator_data = data; } static char chosen_elevator[16]; @@ -181,6 +181,7 @@ int elevator_init(request_queue_t *q, char *name) struct elevator_type *e = NULL; struct elevator_queue *eq; int ret = 0; + void *data; INIT_LIST_HEAD(&q->queue_head); q->last_merge = NULL; @@ -202,10 +203,13 @@ int elevator_init(request_queue_t *q, char *name) if (!eq) return -ENOMEM; - ret = elevator_attach(q, eq); - if (ret) + data = elevator_init_queue(q, eq); + if (!data) { kobject_put(&eq->kobj); + return -ENOMEM; + } + elevator_attach(q, eq, data); return ret; } @@ -722,13 +726,16 @@ int elv_register_queue(struct request_queue *q) return error; } +static void __elv_unregister_queue(elevator_t *e) +{ + kobject_uevent(&e->kobj, KOBJ_REMOVE); + kobject_del(&e->kobj); +} + void elv_unregister_queue(struct request_queue *q) { - if (q) { - elevator_t *e = q->elevator; - kobject_uevent(&e->kobj, KOBJ_REMOVE); - kobject_del(&e->kobj); - } + if (q) + __elv_unregister_queue(q->elevator); } int elv_register(struct elevator_type *e) @@ -780,6 +787,7 @@ EXPORT_SYMBOL_GPL(elv_unregister); static int elevator_switch(request_queue_t *q, struct elevator_type *new_e) { elevator_t *old_elevator, *e; + void *data; /* * Allocate new elevator @@ -788,6 +796,12 @@ static int elevator_switch(request_queue_t *q, struct elevator_type *new_e) if (!e) return 0; + data = elevator_init_queue(q, e); + if (!data) { + kobject_put(&e->kobj); + return 0; + } + /* * Turn on BYPASS and drain all requests w/ elevator private data */ @@ -806,19 +820,19 @@ static int elevator_switch(request_queue_t *q, struct elevator_type *new_e) elv_drain_elevator(q); } - spin_unlock_irq(q->queue_lock); - /* - * unregister old elevator data + * Remember old elevator. */ - elv_unregister_queue(q); old_elevator = q->elevator; /* * attach and start new elevator */ - if (elevator_attach(q, e)) - goto fail; + elevator_attach(q, e, data); + + spin_unlock_irq(q->queue_lock); + + __elv_unregister_queue(old_elevator); if (elv_register_queue(q)) goto fail_register; @@ -837,7 +851,6 @@ fail_register: */ elevator_exit(e); e = NULL; -fail: q->elevator = old_elevator; elv_register_queue(q); clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags); diff --git a/block/noop-iosched.c b/block/noop-iosched.c index f370e4a7fe6d..56a7c620574f 100644 --- a/block/noop-iosched.c +++ b/block/noop-iosched.c @@ -65,16 +65,15 @@ noop_latter_request(request_queue_t *q, struct request *rq) return list_entry(rq->queuelist.next, struct request, queuelist); } -static int noop_init_queue(request_queue_t *q, elevator_t *e) +static void *noop_init_queue(request_queue_t *q, elevator_t *e) { struct noop_data *nd; nd = kmalloc(sizeof(*nd), GFP_KERNEL); if (!nd) - return -ENOMEM; + return NULL; INIT_LIST_HEAD(&nd->queue); - e->elevator_data = nd; - return 0; + return nd; } static void noop_exit_queue(elevator_t *e) |
