[PATCH] 02/05: update ioscheds to use generic dispatch queue
This patch updates all four ioscheds to use generic dispatch queue. There's one behavior change in as-iosched. * In as-iosched, when force dispatching (ELEVATOR_INSERT_BACK), batch_data_dir is reset to REQ_SYNC and changed_batch and new_batch are cleared to zero. This prevernts AS from doing incorrect update_write_batch after the forced dispatched requests are finished. * In cfq-iosched, cfqd->rq_in_driver currently counts the number of activated (removed) requests to determine whether queue-kicking is needed and cfq_max_depth has been reached. With generic dispatch queue, I think counting the number of dispatched requests would be more appropriate. * cfq_max_depth can be lowered to 1 again. Original from Tejun Heo, modified version applied. Signed-off-by: Jens Axboe <axboe@suse.de>
This commit is contained in:
Jens Axboe
Jens Axboe
parent
d9ebb192aa
commit
b4878f245e
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@ -98,7 +98,6 @@ struct as_data {
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struct as_rq *next_arq[2]; /* next in sort order */
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sector_t last_sector[2]; /* last REQ_SYNC & REQ_ASYNC sectors */
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struct list_head *dispatch; /* driver dispatch queue */
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struct list_head *hash; /* request hash */
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unsigned long exit_prob; /* probability a task will exit while
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@ -239,6 +238,25 @@ static struct io_context *as_get_io_context(void)
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return ioc;
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}
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static void as_put_io_context(struct as_rq *arq)
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{
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struct as_io_context *aic;
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if (unlikely(!arq->io_context))
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return;
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aic = arq->io_context->aic;
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if (arq->is_sync == REQ_SYNC && aic) {
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spin_lock(&aic->lock);
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set_bit(AS_TASK_IORUNNING, &aic->state);
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aic->last_end_request = jiffies;
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spin_unlock(&aic->lock);
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}
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put_io_context(arq->io_context);
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}
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/*
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* the back merge hash support functions
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*/
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@ -950,23 +968,12 @@ static void as_completed_request(request_queue_t *q, struct request *rq)
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WARN_ON(!list_empty(&rq->queuelist));
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if (arq->state == AS_RQ_PRESCHED) {
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WARN_ON(arq->io_context);
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goto out;
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}
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if (arq->state == AS_RQ_MERGED)
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goto out_ioc;
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if (arq->state != AS_RQ_REMOVED) {
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printk("arq->state %d\n", arq->state);
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WARN_ON(1);
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goto out;
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}
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if (!blk_fs_request(rq))
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goto out;
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if (ad->changed_batch && ad->nr_dispatched == 1) {
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kblockd_schedule_work(&ad->antic_work);
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ad->changed_batch = 0;
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@ -1001,21 +1008,7 @@ static void as_completed_request(request_queue_t *q, struct request *rq)
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}
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}
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out_ioc:
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if (!arq->io_context)
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goto out;
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if (arq->is_sync == REQ_SYNC) {
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struct as_io_context *aic = arq->io_context->aic;
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if (aic) {
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spin_lock(&aic->lock);
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set_bit(AS_TASK_IORUNNING, &aic->state);
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aic->last_end_request = jiffies;
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spin_unlock(&aic->lock);
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}
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}
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put_io_context(arq->io_context);
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as_put_io_context(arq);
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out:
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arq->state = AS_RQ_POSTSCHED;
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}
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@ -1051,68 +1044,6 @@ static void as_remove_queued_request(request_queue_t *q, struct request *rq)
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as_del_arq_rb(ad, arq);
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}
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/*
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* as_remove_dispatched_request is called to remove a request which has gone
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* to the dispatch list.
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*/
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static void as_remove_dispatched_request(request_queue_t *q, struct request *rq)
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{
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struct as_rq *arq = RQ_DATA(rq);
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struct as_io_context *aic;
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if (!arq) {
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WARN_ON(1);
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return;
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}
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WARN_ON(arq->state != AS_RQ_DISPATCHED);
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WARN_ON(ON_RB(&arq->rb_node));
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if (arq->io_context && arq->io_context->aic) {
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aic = arq->io_context->aic;
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if (aic) {
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WARN_ON(!atomic_read(&aic->nr_dispatched));
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atomic_dec(&aic->nr_dispatched);
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}
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}
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}
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/*
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* as_remove_request is called when a driver has finished with a request.
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* This should be only called for dispatched requests, but for some reason
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* a POWER4 box running hwscan it does not.
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*/
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static void as_remove_request(request_queue_t *q, struct request *rq)
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{
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struct as_rq *arq = RQ_DATA(rq);
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if (unlikely(arq->state == AS_RQ_NEW))
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goto out;
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if (ON_RB(&arq->rb_node)) {
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if (arq->state != AS_RQ_QUEUED) {
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printk("arq->state %d\n", arq->state);
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WARN_ON(1);
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goto out;
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}
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/*
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* We'll lose the aliased request(s) here. I don't think this
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* will ever happen, but if it does, hopefully someone will
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* report it.
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*/
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WARN_ON(!list_empty(&rq->queuelist));
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as_remove_queued_request(q, rq);
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} else {
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if (arq->state != AS_RQ_DISPATCHED) {
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printk("arq->state %d\n", arq->state);
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WARN_ON(1);
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goto out;
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}
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as_remove_dispatched_request(q, rq);
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}
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out:
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arq->state = AS_RQ_REMOVED;
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}
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/*
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* as_fifo_expired returns 0 if there are no expired reads on the fifo,
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* 1 otherwise. It is ratelimited so that we only perform the check once per
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@ -1165,7 +1096,6 @@ static inline int as_batch_expired(struct as_data *ad)
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static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
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{
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struct request *rq = arq->request;
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struct list_head *insert;
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const int data_dir = arq->is_sync;
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BUG_ON(!ON_RB(&arq->rb_node));
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@ -1198,13 +1128,13 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
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/*
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* take it off the sort and fifo list, add to dispatch queue
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*/
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insert = ad->dispatch->prev;
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while (!list_empty(&rq->queuelist)) {
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struct request *__rq = list_entry_rq(rq->queuelist.next);
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struct as_rq *__arq = RQ_DATA(__rq);
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list_move_tail(&__rq->queuelist, ad->dispatch);
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list_del(&__rq->queuelist);
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elv_dispatch_add_tail(ad->q, __rq);
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if (__arq->io_context && __arq->io_context->aic)
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atomic_inc(&__arq->io_context->aic->nr_dispatched);
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@ -1218,7 +1148,8 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
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as_remove_queued_request(ad->q, rq);
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WARN_ON(arq->state != AS_RQ_QUEUED);
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list_add(&rq->queuelist, insert);
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elv_dispatch_sort(ad->q, rq);
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arq->state = AS_RQ_DISPATCHED;
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if (arq->io_context && arq->io_context->aic)
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atomic_inc(&arq->io_context->aic->nr_dispatched);
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@ -1230,12 +1161,42 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
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* read/write expire, batch expire, etc, and moves it to the dispatch
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* queue. Returns 1 if a request was found, 0 otherwise.
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*/
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static int as_dispatch_request(struct as_data *ad)
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static int as_dispatch_request(request_queue_t *q, int force)
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{
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struct as_data *ad = q->elevator->elevator_data;
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struct as_rq *arq;
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const int reads = !list_empty(&ad->fifo_list[REQ_SYNC]);
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const int writes = !list_empty(&ad->fifo_list[REQ_ASYNC]);
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if (unlikely(force)) {
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/*
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* Forced dispatch, accounting is useless. Reset
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* accounting states and dump fifo_lists. Note that
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* batch_data_dir is reset to REQ_SYNC to avoid
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* screwing write batch accounting as write batch
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* accounting occurs on W->R transition.
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*/
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int dispatched = 0;
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ad->batch_data_dir = REQ_SYNC;
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ad->changed_batch = 0;
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ad->new_batch = 0;
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while (ad->next_arq[REQ_SYNC]) {
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as_move_to_dispatch(ad, ad->next_arq[REQ_SYNC]);
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dispatched++;
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}
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ad->last_check_fifo[REQ_SYNC] = jiffies;
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while (ad->next_arq[REQ_ASYNC]) {
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as_move_to_dispatch(ad, ad->next_arq[REQ_ASYNC]);
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dispatched++;
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}
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ad->last_check_fifo[REQ_ASYNC] = jiffies;
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return dispatched;
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}
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/* Signal that the write batch was uncontended, so we can't time it */
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if (ad->batch_data_dir == REQ_ASYNC && !reads) {
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if (ad->current_write_count == 0 || !writes)
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@ -1359,20 +1320,6 @@ fifo_expired:
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return 1;
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}
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static struct request *as_next_request(request_queue_t *q)
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{
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struct as_data *ad = q->elevator->elevator_data;
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struct request *rq = NULL;
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/*
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* if there are still requests on the dispatch queue, grab the first
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*/
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if (!list_empty(ad->dispatch) || as_dispatch_request(ad))
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rq = list_entry_rq(ad->dispatch->next);
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return rq;
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}
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/*
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* Add arq to a list behind alias
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*/
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@ -1410,11 +1357,19 @@ as_add_aliased_request(struct as_data *ad, struct as_rq *arq, struct as_rq *alia
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/*
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* add arq to rbtree and fifo
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*/
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static void as_add_request(struct as_data *ad, struct as_rq *arq)
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static void as_add_request(request_queue_t *q, struct request *rq)
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{
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struct as_data *ad = q->elevator->elevator_data;
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struct as_rq *arq = RQ_DATA(rq);
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struct as_rq *alias;
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int data_dir;
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if (arq->state != AS_RQ_PRESCHED) {
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printk("arq->state: %d\n", arq->state);
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WARN_ON(1);
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}
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arq->state = AS_RQ_NEW;
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if (rq_data_dir(arq->request) == READ
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|| current->flags&PF_SYNCWRITE)
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arq->is_sync = 1;
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@ -1463,96 +1418,24 @@ static void as_add_request(struct as_data *ad, struct as_rq *arq)
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arq->state = AS_RQ_QUEUED;
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}
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static void as_activate_request(request_queue_t *q, struct request *rq)
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{
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struct as_rq *arq = RQ_DATA(rq);
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WARN_ON(arq->state != AS_RQ_DISPATCHED);
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arq->state = AS_RQ_REMOVED;
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if (arq->io_context && arq->io_context->aic)
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atomic_dec(&arq->io_context->aic->nr_dispatched);
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}
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static void as_deactivate_request(request_queue_t *q, struct request *rq)
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{
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struct as_data *ad = q->elevator->elevator_data;
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struct as_rq *arq = RQ_DATA(rq);
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if (arq) {
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if (arq->state == AS_RQ_REMOVED) {
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arq->state = AS_RQ_DISPATCHED;
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if (arq->io_context && arq->io_context->aic)
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atomic_inc(&arq->io_context->aic->nr_dispatched);
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}
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} else
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WARN_ON(blk_fs_request(rq)
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&& (!(rq->flags & (REQ_HARDBARRIER|REQ_SOFTBARRIER))) );
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/* Stop anticipating - let this request get through */
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as_antic_stop(ad);
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}
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/*
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* requeue the request. The request has not been completed, nor is it a
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* new request, so don't touch accounting.
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*/
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static void as_requeue_request(request_queue_t *q, struct request *rq)
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{
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as_deactivate_request(q, rq);
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list_add(&rq->queuelist, &q->queue_head);
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}
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/*
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* Account a request that is inserted directly onto the dispatch queue.
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* arq->io_context->aic->nr_dispatched should not need to be incremented
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* because only new requests should come through here: requeues go through
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* our explicit requeue handler.
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*/
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static void as_account_queued_request(struct as_data *ad, struct request *rq)
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{
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if (blk_fs_request(rq)) {
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struct as_rq *arq = RQ_DATA(rq);
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arq->state = AS_RQ_DISPATCHED;
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ad->nr_dispatched++;
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}
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}
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static void
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as_insert_request(request_queue_t *q, struct request *rq, int where)
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{
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struct as_data *ad = q->elevator->elevator_data;
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struct as_rq *arq = RQ_DATA(rq);
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if (arq) {
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if (arq->state != AS_RQ_PRESCHED) {
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printk("arq->state: %d\n", arq->state);
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WARN_ON(1);
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}
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arq->state = AS_RQ_NEW;
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}
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/* barriers must flush the reorder queue */
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if (unlikely(rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)
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&& where == ELEVATOR_INSERT_SORT)) {
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WARN_ON(1);
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where = ELEVATOR_INSERT_BACK;
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}
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switch (where) {
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case ELEVATOR_INSERT_BACK:
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while (ad->next_arq[REQ_SYNC])
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as_move_to_dispatch(ad, ad->next_arq[REQ_SYNC]);
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while (ad->next_arq[REQ_ASYNC])
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as_move_to_dispatch(ad, ad->next_arq[REQ_ASYNC]);
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list_add_tail(&rq->queuelist, ad->dispatch);
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as_account_queued_request(ad, rq);
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as_antic_stop(ad);
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break;
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case ELEVATOR_INSERT_FRONT:
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list_add(&rq->queuelist, ad->dispatch);
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as_account_queued_request(ad, rq);
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as_antic_stop(ad);
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break;
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case ELEVATOR_INSERT_SORT:
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BUG_ON(!blk_fs_request(rq));
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as_add_request(ad, arq);
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break;
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default:
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BUG();
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return;
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}
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WARN_ON(arq->state != AS_RQ_REMOVED);
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arq->state = AS_RQ_DISPATCHED;
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if (arq->io_context && arq->io_context->aic)
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atomic_inc(&arq->io_context->aic->nr_dispatched);
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}
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/*
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@ -1565,12 +1448,8 @@ static int as_queue_empty(request_queue_t *q)
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{
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struct as_data *ad = q->elevator->elevator_data;
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if (!list_empty(&ad->fifo_list[REQ_ASYNC])
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|| !list_empty(&ad->fifo_list[REQ_SYNC])
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|| !list_empty(ad->dispatch))
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return 0;
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return 1;
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return list_empty(&ad->fifo_list[REQ_ASYNC])
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&& list_empty(&ad->fifo_list[REQ_SYNC]);
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}
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static struct request *
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@ -1763,6 +1642,7 @@ as_merged_requests(request_queue_t *q, struct request *req,
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* kill knowledge of next, this one is a goner
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*/
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as_remove_queued_request(q, next);
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as_put_io_context(anext);
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anext->state = AS_RQ_MERGED;
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}
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@ -1782,7 +1662,7 @@ static void as_work_handler(void *data)
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unsigned long flags;
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spin_lock_irqsave(q->queue_lock, flags);
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if (as_next_request(q))
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if (!as_queue_empty(q))
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q->request_fn(q);
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spin_unlock_irqrestore(q->queue_lock, flags);
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}
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@ -1797,7 +1677,9 @@ static void as_put_request(request_queue_t *q, struct request *rq)
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return;
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}
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if (arq->state != AS_RQ_POSTSCHED && arq->state != AS_RQ_PRESCHED) {
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if (unlikely(arq->state != AS_RQ_POSTSCHED &&
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arq->state != AS_RQ_PRESCHED &&
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arq->state != AS_RQ_MERGED)) {
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printk("arq->state %d\n", arq->state);
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WARN_ON(1);
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}
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@ -1907,7 +1789,6 @@ static int as_init_queue(request_queue_t *q, elevator_t *e)
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INIT_LIST_HEAD(&ad->fifo_list[REQ_ASYNC]);
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ad->sort_list[REQ_SYNC] = RB_ROOT;
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ad->sort_list[REQ_ASYNC] = RB_ROOT;
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ad->dispatch = &q->queue_head;
|
||||
ad->fifo_expire[REQ_SYNC] = default_read_expire;
|
||||
ad->fifo_expire[REQ_ASYNC] = default_write_expire;
|
||||
ad->antic_expire = default_antic_expire;
|
||||
|
|
@ -2072,10 +1953,9 @@ static struct elevator_type iosched_as = {
|
|||
.elevator_merge_fn = as_merge,
|
||||
.elevator_merged_fn = as_merged_request,
|
||||
.elevator_merge_req_fn = as_merged_requests,
|
||||
.elevator_next_req_fn = as_next_request,
|
||||
.elevator_add_req_fn = as_insert_request,
|
||||
.elevator_remove_req_fn = as_remove_request,
|
||||
.elevator_requeue_req_fn = as_requeue_request,
|
||||
.elevator_dispatch_fn = as_dispatch_request,
|
||||
.elevator_add_req_fn = as_add_request,
|
||||
.elevator_activate_req_fn = as_activate_request,
|
||||
.elevator_deactivate_req_fn = as_deactivate_request,
|
||||
.elevator_queue_empty_fn = as_queue_empty,
|
||||
.elevator_completed_req_fn = as_completed_request,
|
||||
|
|
|
|||
|
|
@ -84,7 +84,6 @@ static int cfq_max_depth = 2;
|
|||
(node)->rb_left = NULL; \
|
||||
} while (0)
|
||||
#define RB_CLEAR_ROOT(root) ((root)->rb_node = NULL)
|
||||
#define ON_RB(node) ((node)->rb_color != RB_NONE)
|
||||
#define rb_entry_crq(node) rb_entry((node), struct cfq_rq, rb_node)
|
||||
#define rq_rb_key(rq) (rq)->sector
|
||||
|
||||
|
|
@ -271,10 +270,7 @@ CFQ_CFQQ_FNS(expired);
|
|||
#undef CFQ_CFQQ_FNS
|
||||
|
||||
enum cfq_rq_state_flags {
|
||||
CFQ_CRQ_FLAG_in_flight = 0,
|
||||
CFQ_CRQ_FLAG_in_driver,
|
||||
CFQ_CRQ_FLAG_is_sync,
|
||||
CFQ_CRQ_FLAG_requeued,
|
||||
CFQ_CRQ_FLAG_is_sync = 0,
|
||||
};
|
||||
|
||||
#define CFQ_CRQ_FNS(name) \
|
||||
|
|
@ -291,14 +287,11 @@ static inline int cfq_crq_##name(const struct cfq_rq *crq) \
|
|||
return (crq->crq_flags & (1 << CFQ_CRQ_FLAG_##name)) != 0; \
|
||||
}
|
||||
|
||||
CFQ_CRQ_FNS(in_flight);
|
||||
CFQ_CRQ_FNS(in_driver);
|
||||
CFQ_CRQ_FNS(is_sync);
|
||||
CFQ_CRQ_FNS(requeued);
|
||||
#undef CFQ_CRQ_FNS
|
||||
|
||||
static struct cfq_queue *cfq_find_cfq_hash(struct cfq_data *, unsigned int, unsigned short);
|
||||
static void cfq_dispatch_sort(request_queue_t *, struct cfq_rq *);
|
||||
static void cfq_dispatch_insert(request_queue_t *, struct cfq_rq *);
|
||||
static void cfq_put_cfqd(struct cfq_data *cfqd);
|
||||
|
||||
#define process_sync(tsk) ((tsk)->flags & PF_SYNCWRITE)
|
||||
|
|
@ -347,18 +340,13 @@ static struct request *cfq_find_rq_hash(struct cfq_data *cfqd, sector_t offset)
|
|||
return NULL;
|
||||
}
|
||||
|
||||
static inline int cfq_pending_requests(struct cfq_data *cfqd)
|
||||
{
|
||||
return !list_empty(&cfqd->queue->queue_head) || cfqd->busy_queues;
|
||||
}
|
||||
|
||||
/*
|
||||
* 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)
|
||||
{
|
||||
if (!cfqd->rq_in_driver && cfq_pending_requests(cfqd))
|
||||
if (!cfqd->rq_in_driver && cfqd->busy_queues)
|
||||
kblockd_schedule_work(&cfqd->unplug_work);
|
||||
}
|
||||
|
||||
|
|
@ -366,7 +354,7 @@ static int cfq_queue_empty(request_queue_t *q)
|
|||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
|
||||
return !cfq_pending_requests(cfqd);
|
||||
return !cfqd->busy_queues;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -386,11 +374,6 @@ cfq_choose_req(struct cfq_data *cfqd, struct cfq_rq *crq1, struct cfq_rq *crq2)
|
|||
if (crq2 == NULL)
|
||||
return crq1;
|
||||
|
||||
if (cfq_crq_requeued(crq1) && !cfq_crq_requeued(crq2))
|
||||
return crq1;
|
||||
else if (cfq_crq_requeued(crq2) && !cfq_crq_requeued(crq1))
|
||||
return crq2;
|
||||
|
||||
if (cfq_crq_is_sync(crq1) && !cfq_crq_is_sync(crq2))
|
||||
return crq1;
|
||||
else if (cfq_crq_is_sync(crq2) && !cfq_crq_is_sync(crq1))
|
||||
|
|
@ -461,10 +444,7 @@ cfq_find_next_crq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
|
|||
struct cfq_rq *crq_next = NULL, *crq_prev = NULL;
|
||||
struct rb_node *rbnext, *rbprev;
|
||||
|
||||
rbnext = NULL;
|
||||
if (ON_RB(&last->rb_node))
|
||||
rbnext = rb_next(&last->rb_node);
|
||||
if (!rbnext) {
|
||||
if (!(rbnext = rb_next(&last->rb_node))) {
|
||||
rbnext = rb_first(&cfqq->sort_list);
|
||||
if (rbnext == &last->rb_node)
|
||||
rbnext = NULL;
|
||||
|
|
@ -545,13 +525,13 @@ static void cfq_resort_rr_list(struct cfq_queue *cfqq, int preempted)
|
|||
* the pending list according to last request service
|
||||
*/
|
||||
static inline void
|
||||
cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq, int requeue)
|
||||
cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
|
||||
{
|
||||
BUG_ON(cfq_cfqq_on_rr(cfqq));
|
||||
cfq_mark_cfqq_on_rr(cfqq);
|
||||
cfqd->busy_queues++;
|
||||
|
||||
cfq_resort_rr_list(cfqq, requeue);
|
||||
cfq_resort_rr_list(cfqq, 0);
|
||||
}
|
||||
|
||||
static inline void
|
||||
|
|
@ -571,22 +551,19 @@ cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
|
|||
static inline void cfq_del_crq_rb(struct cfq_rq *crq)
|
||||
{
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
struct cfq_data *cfqd = cfqq->cfqd;
|
||||
const int sync = cfq_crq_is_sync(crq);
|
||||
|
||||
if (ON_RB(&crq->rb_node)) {
|
||||
struct cfq_data *cfqd = cfqq->cfqd;
|
||||
const int sync = cfq_crq_is_sync(crq);
|
||||
BUG_ON(!cfqq->queued[sync]);
|
||||
cfqq->queued[sync]--;
|
||||
|
||||
BUG_ON(!cfqq->queued[sync]);
|
||||
cfqq->queued[sync]--;
|
||||
cfq_update_next_crq(crq);
|
||||
|
||||
cfq_update_next_crq(crq);
|
||||
rb_erase(&crq->rb_node, &cfqq->sort_list);
|
||||
RB_CLEAR_COLOR(&crq->rb_node);
|
||||
|
||||
rb_erase(&crq->rb_node, &cfqq->sort_list);
|
||||
RB_CLEAR_COLOR(&crq->rb_node);
|
||||
|
||||
if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list))
|
||||
cfq_del_cfqq_rr(cfqd, cfqq);
|
||||
}
|
||||
if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list))
|
||||
cfq_del_cfqq_rr(cfqd, cfqq);
|
||||
}
|
||||
|
||||
static struct cfq_rq *
|
||||
|
|
@ -627,12 +604,12 @@ static void cfq_add_crq_rb(struct cfq_rq *crq)
|
|||
* if that happens, put the alias on the dispatch list
|
||||
*/
|
||||
while ((__alias = __cfq_add_crq_rb(crq)) != NULL)
|
||||
cfq_dispatch_sort(cfqd->queue, __alias);
|
||||
cfq_dispatch_insert(cfqd->queue, __alias);
|
||||
|
||||
rb_insert_color(&crq->rb_node, &cfqq->sort_list);
|
||||
|
||||
if (!cfq_cfqq_on_rr(cfqq))
|
||||
cfq_add_cfqq_rr(cfqd, cfqq, cfq_crq_requeued(crq));
|
||||
cfq_add_cfqq_rr(cfqd, cfqq);
|
||||
|
||||
/*
|
||||
* check if this request is a better next-serve candidate
|
||||
|
|
@ -643,10 +620,8 @@ static void cfq_add_crq_rb(struct cfq_rq *crq)
|
|||
static inline void
|
||||
cfq_reposition_crq_rb(struct cfq_queue *cfqq, struct cfq_rq *crq)
|
||||
{
|
||||
if (ON_RB(&crq->rb_node)) {
|
||||
rb_erase(&crq->rb_node, &cfqq->sort_list);
|
||||
cfqq->queued[cfq_crq_is_sync(crq)]--;
|
||||
}
|
||||
rb_erase(&crq->rb_node, &cfqq->sort_list);
|
||||
cfqq->queued[cfq_crq_is_sync(crq)]--;
|
||||
|
||||
cfq_add_crq_rb(crq);
|
||||
}
|
||||
|
|
@ -676,49 +651,28 @@ out:
|
|||
return NULL;
|
||||
}
|
||||
|
||||
static void cfq_activate_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
|
||||
cfqd->rq_in_driver++;
|
||||
}
|
||||
|
||||
static void cfq_deactivate_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
struct cfq_rq *crq = RQ_DATA(rq);
|
||||
|
||||
if (crq) {
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
|
||||
if (cfq_crq_in_driver(crq)) {
|
||||
cfq_clear_crq_in_driver(crq);
|
||||
WARN_ON(!cfqd->rq_in_driver);
|
||||
cfqd->rq_in_driver--;
|
||||
}
|
||||
if (cfq_crq_in_flight(crq)) {
|
||||
const int sync = cfq_crq_is_sync(crq);
|
||||
|
||||
cfq_clear_crq_in_flight(crq);
|
||||
WARN_ON(!cfqq->on_dispatch[sync]);
|
||||
cfqq->on_dispatch[sync]--;
|
||||
}
|
||||
cfq_mark_crq_requeued(crq);
|
||||
}
|
||||
WARN_ON(!cfqd->rq_in_driver);
|
||||
cfqd->rq_in_driver--;
|
||||
}
|
||||
|
||||
/*
|
||||
* make sure the service time gets corrected on reissue of this request
|
||||
*/
|
||||
static void cfq_requeue_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
cfq_deactivate_request(q, rq);
|
||||
list_add(&rq->queuelist, &q->queue_head);
|
||||
}
|
||||
|
||||
static void cfq_remove_request(request_queue_t *q, struct request *rq)
|
||||
static void cfq_remove_request(struct request *rq)
|
||||
{
|
||||
struct cfq_rq *crq = RQ_DATA(rq);
|
||||
|
||||
if (crq) {
|
||||
list_del_init(&rq->queuelist);
|
||||
cfq_del_crq_rb(crq);
|
||||
cfq_remove_merge_hints(q, crq);
|
||||
|
||||
}
|
||||
list_del_init(&rq->queuelist);
|
||||
cfq_del_crq_rb(crq);
|
||||
cfq_remove_merge_hints(rq->q, crq);
|
||||
}
|
||||
|
||||
static int
|
||||
|
|
@ -762,7 +716,7 @@ static void cfq_merged_request(request_queue_t *q, struct request *req)
|
|||
cfq_del_crq_hash(crq);
|
||||
cfq_add_crq_hash(cfqd, crq);
|
||||
|
||||
if (ON_RB(&crq->rb_node) && (rq_rb_key(req) != crq->rb_key)) {
|
||||
if (rq_rb_key(req) != crq->rb_key) {
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
|
||||
cfq_update_next_crq(crq);
|
||||
|
|
@ -785,7 +739,7 @@ cfq_merged_requests(request_queue_t *q, struct request *rq,
|
|||
time_before(next->start_time, rq->start_time))
|
||||
list_move(&rq->queuelist, &next->queuelist);
|
||||
|
||||
cfq_remove_request(q, next);
|
||||
cfq_remove_request(next);
|
||||
}
|
||||
|
||||
static inline void
|
||||
|
|
@ -992,53 +946,15 @@ static int cfq_arm_slice_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
|
|||
return 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* we dispatch cfqd->cfq_quantum requests in total from the rr_list queues,
|
||||
* this function sector sorts the selected request to minimize seeks. we start
|
||||
* at cfqd->last_sector, not 0.
|
||||
*/
|
||||
static void cfq_dispatch_sort(request_queue_t *q, struct cfq_rq *crq)
|
||||
static void cfq_dispatch_insert(request_queue_t *q, struct cfq_rq *crq)
|
||||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
struct list_head *head = &q->queue_head, *entry = head;
|
||||
struct request *__rq;
|
||||
sector_t last;
|
||||
|
||||
list_del(&crq->request->queuelist);
|
||||
|
||||
last = cfqd->last_sector;
|
||||
list_for_each_entry_reverse(__rq, head, queuelist) {
|
||||
struct cfq_rq *__crq = RQ_DATA(__rq);
|
||||
|
||||
if (blk_barrier_rq(__rq))
|
||||
break;
|
||||
if (!blk_fs_request(__rq))
|
||||
break;
|
||||
if (cfq_crq_requeued(__crq))
|
||||
break;
|
||||
|
||||
if (__rq->sector <= crq->request->sector)
|
||||
break;
|
||||
if (__rq->sector > last && crq->request->sector < last) {
|
||||
last = crq->request->sector + crq->request->nr_sectors;
|
||||
break;
|
||||
}
|
||||
entry = &__rq->queuelist;
|
||||
}
|
||||
|
||||
cfqd->last_sector = last;
|
||||
|
||||
cfqq->next_crq = cfq_find_next_crq(cfqd, cfqq, crq);
|
||||
|
||||
cfq_del_crq_rb(crq);
|
||||
cfq_remove_merge_hints(q, crq);
|
||||
|
||||
cfq_mark_crq_in_flight(crq);
|
||||
cfq_clear_crq_requeued(crq);
|
||||
|
||||
cfq_remove_request(crq->request);
|
||||
cfqq->on_dispatch[cfq_crq_is_sync(crq)]++;
|
||||
list_add_tail(&crq->request->queuelist, entry);
|
||||
elv_dispatch_sort(q, crq->request);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -1159,7 +1075,7 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq,
|
|||
/*
|
||||
* finally, insert request into driver dispatch list
|
||||
*/
|
||||
cfq_dispatch_sort(cfqd->queue, crq);
|
||||
cfq_dispatch_insert(cfqd->queue, crq);
|
||||
|
||||
cfqd->dispatch_slice++;
|
||||
dispatched++;
|
||||
|
|
@ -1194,7 +1110,7 @@ __cfq_dispatch_requests(struct cfq_data *cfqd, struct cfq_queue *cfqq,
|
|||
}
|
||||
|
||||
static int
|
||||
cfq_dispatch_requests(request_queue_t *q, int max_dispatch, int force)
|
||||
cfq_dispatch_requests(request_queue_t *q, int force)
|
||||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
struct cfq_queue *cfqq;
|
||||
|
|
@ -1204,12 +1120,25 @@ cfq_dispatch_requests(request_queue_t *q, int max_dispatch, int force)
|
|||
|
||||
cfqq = cfq_select_queue(cfqd, force);
|
||||
if (cfqq) {
|
||||
int max_dispatch;
|
||||
|
||||
/*
|
||||
* if idle window is disabled, allow queue buildup
|
||||
*/
|
||||
if (!cfq_cfqq_idle_window(cfqq) &&
|
||||
cfqd->rq_in_driver >= cfqd->cfq_max_depth)
|
||||
return 0;
|
||||
|
||||
cfq_clear_cfqq_must_dispatch(cfqq);
|
||||
cfq_clear_cfqq_wait_request(cfqq);
|
||||
del_timer(&cfqd->idle_slice_timer);
|
||||
|
||||
if (cfq_class_idle(cfqq))
|
||||
max_dispatch = 1;
|
||||
if (!force) {
|
||||
max_dispatch = cfqd->cfq_quantum;
|
||||
if (cfq_class_idle(cfqq))
|
||||
max_dispatch = 1;
|
||||
} else
|
||||
max_dispatch = INT_MAX;
|
||||
|
||||
return __cfq_dispatch_requests(cfqd, cfqq, max_dispatch);
|
||||
}
|
||||
|
|
@ -1217,93 +1146,6 @@ cfq_dispatch_requests(request_queue_t *q, int max_dispatch, int force)
|
|||
return 0;
|
||||
}
|
||||
|
||||
static inline void cfq_account_dispatch(struct cfq_rq *crq)
|
||||
{
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
struct cfq_data *cfqd = cfqq->cfqd;
|
||||
|
||||
if (unlikely(!blk_fs_request(crq->request)))
|
||||
return;
|
||||
|
||||
/*
|
||||
* accounted bit is necessary since some drivers will call
|
||||
* elv_next_request() many times for the same request (eg ide)
|
||||
*/
|
||||
if (cfq_crq_in_driver(crq))
|
||||
return;
|
||||
|
||||
cfq_mark_crq_in_driver(crq);
|
||||
cfqd->rq_in_driver++;
|
||||
}
|
||||
|
||||
static inline void
|
||||
cfq_account_completion(struct cfq_queue *cfqq, struct cfq_rq *crq)
|
||||
{
|
||||
struct cfq_data *cfqd = cfqq->cfqd;
|
||||
unsigned long now;
|
||||
|
||||
if (!cfq_crq_in_driver(crq))
|
||||
return;
|
||||
|
||||
now = jiffies;
|
||||
|
||||
WARN_ON(!cfqd->rq_in_driver);
|
||||
cfqd->rq_in_driver--;
|
||||
|
||||
if (!cfq_class_idle(cfqq))
|
||||
cfqd->last_end_request = now;
|
||||
|
||||
if (!cfq_cfqq_dispatched(cfqq)) {
|
||||
if (cfq_cfqq_on_rr(cfqq)) {
|
||||
cfqq->service_last = now;
|
||||
cfq_resort_rr_list(cfqq, 0);
|
||||
}
|
||||
if (cfq_cfqq_expired(cfqq)) {
|
||||
__cfq_slice_expired(cfqd, cfqq, 0);
|
||||
cfq_schedule_dispatch(cfqd);
|
||||
}
|
||||
}
|
||||
|
||||
if (cfq_crq_is_sync(crq))
|
||||
crq->io_context->last_end_request = now;
|
||||
}
|
||||
|
||||
static struct request *cfq_next_request(request_queue_t *q)
|
||||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
struct request *rq;
|
||||
|
||||
if (!list_empty(&q->queue_head)) {
|
||||
struct cfq_rq *crq;
|
||||
dispatch:
|
||||
rq = list_entry_rq(q->queue_head.next);
|
||||
|
||||
crq = RQ_DATA(rq);
|
||||
if (crq) {
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
|
||||
/*
|
||||
* if idle window is disabled, allow queue buildup
|
||||
*/
|
||||
if (!cfq_crq_in_driver(crq) &&
|
||||
!cfq_cfqq_idle_window(cfqq) &&
|
||||
!blk_barrier_rq(rq) &&
|
||||
cfqd->rq_in_driver >= cfqd->cfq_max_depth)
|
||||
return NULL;
|
||||
|
||||
cfq_remove_merge_hints(q, crq);
|
||||
cfq_account_dispatch(crq);
|
||||
}
|
||||
|
||||
return rq;
|
||||
}
|
||||
|
||||
if (cfq_dispatch_requests(q, cfqd->cfq_quantum, 0))
|
||||
goto dispatch;
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* task holds one reference to the queue, dropped when task exits. each crq
|
||||
* in-flight on this queue also holds a reference, dropped when crq is freed.
|
||||
|
|
@ -1816,8 +1658,9 @@ cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
|
|||
}
|
||||
}
|
||||
|
||||
static void cfq_enqueue(struct cfq_data *cfqd, struct request *rq)
|
||||
static void cfq_insert_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
struct cfq_rq *crq = RQ_DATA(rq);
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
|
||||
|
|
@ -1837,56 +1680,37 @@ static void cfq_enqueue(struct cfq_data *cfqd, struct request *rq)
|
|||
cfq_crq_enqueued(cfqd, cfqq, crq);
|
||||
}
|
||||
|
||||
static void
|
||||
cfq_insert_request(request_queue_t *q, struct request *rq, int where)
|
||||
{
|
||||
struct cfq_data *cfqd = q->elevator->elevator_data;
|
||||
|
||||
switch (where) {
|
||||
case ELEVATOR_INSERT_BACK:
|
||||
while (cfq_dispatch_requests(q, INT_MAX, 1))
|
||||
;
|
||||
list_add_tail(&rq->queuelist, &q->queue_head);
|
||||
/*
|
||||
* If we were idling with pending requests on
|
||||
* inactive cfqqs, force dispatching will
|
||||
* remove the idle timer and the queue won't
|
||||
* be kicked by __make_request() afterward.
|
||||
* Kick it here.
|
||||
*/
|
||||
cfq_schedule_dispatch(cfqd);
|
||||
break;
|
||||
case ELEVATOR_INSERT_FRONT:
|
||||
list_add(&rq->queuelist, &q->queue_head);
|
||||
break;
|
||||
case ELEVATOR_INSERT_SORT:
|
||||
BUG_ON(!blk_fs_request(rq));
|
||||
cfq_enqueue(cfqd, rq);
|
||||
break;
|
||||
default:
|
||||
printk("%s: bad insert point %d\n", __FUNCTION__,where);
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
||||
static void cfq_completed_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct cfq_rq *crq = RQ_DATA(rq);
|
||||
struct cfq_queue *cfqq;
|
||||
struct cfq_queue *cfqq = crq->cfq_queue;
|
||||
struct cfq_data *cfqd = cfqq->cfqd;
|
||||
const int sync = cfq_crq_is_sync(crq);
|
||||
unsigned long now;
|
||||
|
||||
if (unlikely(!blk_fs_request(rq)))
|
||||
return;
|
||||
now = jiffies;
|
||||
|
||||
cfqq = crq->cfq_queue;
|
||||
WARN_ON(!cfqd->rq_in_driver);
|
||||
WARN_ON(!cfqq->on_dispatch[sync]);
|
||||
cfqd->rq_in_driver--;
|
||||
cfqq->on_dispatch[sync]--;
|
||||
|
||||
if (cfq_crq_in_flight(crq)) {
|
||||
const int sync = cfq_crq_is_sync(crq);
|
||||
if (!cfq_class_idle(cfqq))
|
||||
cfqd->last_end_request = now;
|
||||
|
||||
WARN_ON(!cfqq->on_dispatch[sync]);
|
||||
cfqq->on_dispatch[sync]--;
|
||||
if (!cfq_cfqq_dispatched(cfqq)) {
|
||||
if (cfq_cfqq_on_rr(cfqq)) {
|
||||
cfqq->service_last = now;
|
||||
cfq_resort_rr_list(cfqq, 0);
|
||||
}
|
||||
if (cfq_cfqq_expired(cfqq)) {
|
||||
__cfq_slice_expired(cfqd, cfqq, 0);
|
||||
cfq_schedule_dispatch(cfqd);
|
||||
}
|
||||
}
|
||||
|
||||
cfq_account_completion(cfqq, crq);
|
||||
if (cfq_crq_is_sync(crq))
|
||||
crq->io_context->last_end_request = now;
|
||||
}
|
||||
|
||||
static struct request *
|
||||
|
|
@ -2118,9 +1942,6 @@ cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio,
|
|||
INIT_HLIST_NODE(&crq->hash);
|
||||
crq->cfq_queue = cfqq;
|
||||
crq->io_context = cic;
|
||||
cfq_clear_crq_in_flight(crq);
|
||||
cfq_clear_crq_in_driver(crq);
|
||||
cfq_clear_crq_requeued(crq);
|
||||
|
||||
if (rw == READ || process_sync(tsk))
|
||||
cfq_mark_crq_is_sync(crq);
|
||||
|
|
@ -2201,7 +2022,7 @@ static void cfq_idle_slice_timer(unsigned long data)
|
|||
* only expire and reinvoke request handler, if there are
|
||||
* other queues with pending requests
|
||||
*/
|
||||
if (!cfq_pending_requests(cfqd)) {
|
||||
if (!cfqd->busy_queues) {
|
||||
cfqd->idle_slice_timer.expires = min(now + cfqd->cfq_slice_idle, cfqq->slice_end);
|
||||
add_timer(&cfqd->idle_slice_timer);
|
||||
goto out_cont;
|
||||
|
|
@ -2576,10 +2397,9 @@ static struct elevator_type iosched_cfq = {
|
|||
.elevator_merge_fn = cfq_merge,
|
||||
.elevator_merged_fn = cfq_merged_request,
|
||||
.elevator_merge_req_fn = cfq_merged_requests,
|
||||
.elevator_next_req_fn = cfq_next_request,
|
||||
.elevator_dispatch_fn = cfq_dispatch_requests,
|
||||
.elevator_add_req_fn = cfq_insert_request,
|
||||
.elevator_remove_req_fn = cfq_remove_request,
|
||||
.elevator_requeue_req_fn = cfq_requeue_request,
|
||||
.elevator_activate_req_fn = cfq_activate_request,
|
||||
.elevator_deactivate_req_fn = cfq_deactivate_request,
|
||||
.elevator_queue_empty_fn = cfq_queue_empty,
|
||||
.elevator_completed_req_fn = cfq_completed_request,
|
||||
|
|
|
|||
|
|
@ -50,7 +50,6 @@ struct deadline_data {
|
|||
* next in sort order. read, write or both are NULL
|
||||
*/
|
||||
struct deadline_rq *next_drq[2];
|
||||
struct list_head *dispatch; /* driver dispatch queue */
|
||||
struct list_head *hash; /* request hash */
|
||||
unsigned int batching; /* number of sequential requests made */
|
||||
sector_t last_sector; /* head position */
|
||||
|
|
@ -239,10 +238,9 @@ deadline_del_drq_rb(struct deadline_data *dd, struct deadline_rq *drq)
|
|||
dd->next_drq[data_dir] = rb_entry_drq(rbnext);
|
||||
}
|
||||
|
||||
if (ON_RB(&drq->rb_node)) {
|
||||
rb_erase(&drq->rb_node, DRQ_RB_ROOT(dd, drq));
|
||||
RB_CLEAR(&drq->rb_node);
|
||||
}
|
||||
BUG_ON(!ON_RB(&drq->rb_node));
|
||||
rb_erase(&drq->rb_node, DRQ_RB_ROOT(dd, drq));
|
||||
RB_CLEAR(&drq->rb_node);
|
||||
}
|
||||
|
||||
static struct request *
|
||||
|
|
@ -286,7 +284,7 @@ deadline_find_first_drq(struct deadline_data *dd, int data_dir)
|
|||
/*
|
||||
* add drq to rbtree and fifo
|
||||
*/
|
||||
static inline void
|
||||
static void
|
||||
deadline_add_request(struct request_queue *q, struct request *rq)
|
||||
{
|
||||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
|
|
@ -315,14 +313,11 @@ deadline_add_request(struct request_queue *q, struct request *rq)
|
|||
static void deadline_remove_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct deadline_rq *drq = RQ_DATA(rq);
|
||||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
|
||||
if (drq) {
|
||||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
|
||||
list_del_init(&drq->fifo);
|
||||
deadline_remove_merge_hints(q, drq);
|
||||
deadline_del_drq_rb(dd, drq);
|
||||
}
|
||||
list_del_init(&drq->fifo);
|
||||
deadline_remove_merge_hints(q, drq);
|
||||
deadline_del_drq_rb(dd, drq);
|
||||
}
|
||||
|
||||
static int
|
||||
|
|
@ -452,7 +447,7 @@ deadline_move_to_dispatch(struct deadline_data *dd, struct deadline_rq *drq)
|
|||
request_queue_t *q = drq->request->q;
|
||||
|
||||
deadline_remove_request(q, drq->request);
|
||||
list_add_tail(&drq->request->queuelist, dd->dispatch);
|
||||
elv_dispatch_add_tail(q, drq->request);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -502,8 +497,9 @@ static inline int deadline_check_fifo(struct deadline_data *dd, int ddir)
|
|||
* deadline_dispatch_requests selects the best request according to
|
||||
* read/write expire, fifo_batch, etc
|
||||
*/
|
||||
static int deadline_dispatch_requests(struct deadline_data *dd)
|
||||
static int deadline_dispatch_requests(request_queue_t *q, int force)
|
||||
{
|
||||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
const int reads = !list_empty(&dd->fifo_list[READ]);
|
||||
const int writes = !list_empty(&dd->fifo_list[WRITE]);
|
||||
struct deadline_rq *drq;
|
||||
|
|
@ -597,65 +593,12 @@ dispatch_request:
|
|||
return 1;
|
||||
}
|
||||
|
||||
static struct request *deadline_next_request(request_queue_t *q)
|
||||
{
|
||||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
struct request *rq;
|
||||
|
||||
/*
|
||||
* if there are still requests on the dispatch queue, grab the first one
|
||||
*/
|
||||
if (!list_empty(dd->dispatch)) {
|
||||
dispatch:
|
||||
rq = list_entry_rq(dd->dispatch->next);
|
||||
return rq;
|
||||
}
|
||||
|
||||
if (deadline_dispatch_requests(dd))
|
||||
goto dispatch;
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static void
|
||||
deadline_insert_request(request_queue_t *q, struct request *rq, int where)
|
||||
{
|
||||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
|
||||
/* barriers must flush the reorder queue */
|
||||
if (unlikely(rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)
|
||||
&& where == ELEVATOR_INSERT_SORT))
|
||||
where = ELEVATOR_INSERT_BACK;
|
||||
|
||||
switch (where) {
|
||||
case ELEVATOR_INSERT_BACK:
|
||||
while (deadline_dispatch_requests(dd))
|
||||
;
|
||||
list_add_tail(&rq->queuelist, dd->dispatch);
|
||||
break;
|
||||
case ELEVATOR_INSERT_FRONT:
|
||||
list_add(&rq->queuelist, dd->dispatch);
|
||||
break;
|
||||
case ELEVATOR_INSERT_SORT:
|
||||
BUG_ON(!blk_fs_request(rq));
|
||||
deadline_add_request(q, rq);
|
||||
break;
|
||||
default:
|
||||
printk("%s: bad insert point %d\n", __FUNCTION__,where);
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
||||
static int deadline_queue_empty(request_queue_t *q)
|
||||
{
|
||||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
|
||||
if (!list_empty(&dd->fifo_list[WRITE])
|
||||
|| !list_empty(&dd->fifo_list[READ])
|
||||
|| !list_empty(dd->dispatch))
|
||||
return 0;
|
||||
|
||||
return 1;
|
||||
return list_empty(&dd->fifo_list[WRITE])
|
||||
&& list_empty(&dd->fifo_list[READ]);
|
||||
}
|
||||
|
||||
static struct request *
|
||||
|
|
@ -733,7 +676,6 @@ static int deadline_init_queue(request_queue_t *q, elevator_t *e)
|
|||
INIT_LIST_HEAD(&dd->fifo_list[WRITE]);
|
||||
dd->sort_list[READ] = RB_ROOT;
|
||||
dd->sort_list[WRITE] = RB_ROOT;
|
||||
dd->dispatch = &q->queue_head;
|
||||
dd->fifo_expire[READ] = read_expire;
|
||||
dd->fifo_expire[WRITE] = write_expire;
|
||||
dd->writes_starved = writes_starved;
|
||||
|
|
@ -748,10 +690,8 @@ static void deadline_put_request(request_queue_t *q, struct request *rq)
|
|||
struct deadline_data *dd = q->elevator->elevator_data;
|
||||
struct deadline_rq *drq = RQ_DATA(rq);
|
||||
|
||||
if (drq) {
|
||||
mempool_free(drq, dd->drq_pool);
|
||||
rq->elevator_private = NULL;
|
||||
}
|
||||
mempool_free(drq, dd->drq_pool);
|
||||
rq->elevator_private = NULL;
|
||||
}
|
||||
|
||||
static int
|
||||
|
|
@ -917,9 +857,8 @@ static struct elevator_type iosched_deadline = {
|
|||
.elevator_merge_fn = deadline_merge,
|
||||
.elevator_merged_fn = deadline_merged_request,
|
||||
.elevator_merge_req_fn = deadline_merged_requests,
|
||||
.elevator_next_req_fn = deadline_next_request,
|
||||
.elevator_add_req_fn = deadline_insert_request,
|
||||
.elevator_remove_req_fn = deadline_remove_request,
|
||||
.elevator_dispatch_fn = deadline_dispatch_requests,
|
||||
.elevator_add_req_fn = deadline_add_request,
|
||||
.elevator_queue_empty_fn = deadline_queue_empty,
|
||||
.elevator_former_req_fn = deadline_former_request,
|
||||
.elevator_latter_req_fn = deadline_latter_request,
|
||||
|
|
|
|||
|
|
@ -28,13 +28,9 @@ static void elevator_noop_merge_requests(request_queue_t *q, struct request *req
|
|||
list_del_init(&next->queuelist);
|
||||
}
|
||||
|
||||
static void elevator_noop_add_request(request_queue_t *q, struct request *rq,
|
||||
int where)
|
||||
static void elevator_noop_add_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
if (where == ELEVATOR_INSERT_FRONT)
|
||||
list_add(&rq->queuelist, &q->queue_head);
|
||||
else
|
||||
list_add_tail(&rq->queuelist, &q->queue_head);
|
||||
elv_dispatch_add_tail(q, rq);
|
||||
|
||||
/*
|
||||
* new merges must not precede this barrier
|
||||
|
|
@ -45,19 +41,16 @@ static void elevator_noop_add_request(request_queue_t *q, struct request *rq,
|
|||
q->last_merge = rq;
|
||||
}
|
||||
|
||||
static struct request *elevator_noop_next_request(request_queue_t *q)
|
||||
static int elevator_noop_dispatch(request_queue_t *q, int force)
|
||||
{
|
||||
if (!list_empty(&q->queue_head))
|
||||
return list_entry_rq(q->queue_head.next);
|
||||
|
||||
return NULL;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct elevator_type elevator_noop = {
|
||||
.ops = {
|
||||
.elevator_merge_fn = elevator_noop_merge,
|
||||
.elevator_merge_req_fn = elevator_noop_merge_requests,
|
||||
.elevator_next_req_fn = elevator_noop_next_request,
|
||||
.elevator_dispatch_fn = elevator_noop_dispatch,
|
||||
.elevator_add_req_fn = elevator_noop_add_request,
|
||||
},
|
||||
.elevator_name = "noop",
|
||||
|
|
|
|||
Reference in New Issue