[PATCH] as-iosched: kill arq
Get rid of the as_rq request type. With the added elevator_private2, we have enough room in struct request to get rid of any arq allocation/free for each request. Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Nick Piggin <npiggin@suse.de>
This commit is contained in:
Jens Axboe
Jens Axboe
parent
5e70537479
commit
8a8e674cb1
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@ -92,7 +92,7 @@ struct as_data {
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struct rb_root sort_list[2];
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struct list_head fifo_list[2];
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struct as_rq *next_arq[2]; /* next in sort order */
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struct request *next_rq[2]; /* next in sort order */
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sector_t last_sector[2]; /* last REQ_SYNC & REQ_ASYNC sectors */
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unsigned long exit_prob; /* probability a task will exit while
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@ -113,7 +113,6 @@ struct as_data {
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int write_batch_count; /* max # of reqs in a write batch */
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int current_write_count; /* how many requests left this batch */
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int write_batch_idled; /* has the write batch gone idle? */
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mempool_t *arq_pool;
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enum anticipation_status antic_status;
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unsigned long antic_start; /* jiffies: when it started */
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@ -146,22 +145,14 @@ enum arq_state {
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AS_RQ_POSTSCHED, /* when they shouldn't be */
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};
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struct as_rq {
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struct request *request;
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struct io_context *io_context; /* The submitting task */
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enum arq_state state;
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};
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#define RQ_DATA(rq) ((struct as_rq *) (rq)->elevator_private)
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static kmem_cache_t *arq_pool;
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#define RQ_IOC(rq) ((struct io_context *) (rq)->elevator_private)
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#define RQ_STATE(rq) ((enum arq_state)(rq)->elevator_private2)
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#define RQ_SET_STATE(rq, state) ((rq)->elevator_private2 = (void *) state)
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static atomic_t ioc_count = ATOMIC_INIT(0);
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static struct completion *ioc_gone;
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static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq);
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static void as_move_to_dispatch(struct as_data *ad, struct request *rq);
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static void as_antic_stop(struct as_data *ad);
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/*
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@ -231,23 +222,23 @@ 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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static void as_put_io_context(struct request *rq)
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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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if (unlikely(!RQ_IOC(rq)))
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return;
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aic = arq->io_context->aic;
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aic = RQ_IOC(rq)->aic;
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if (rq_is_sync(arq->request) && aic) {
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if (rq_is_sync(rq) && 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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put_io_context(RQ_IOC(rq));
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}
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/*
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@ -255,17 +246,17 @@ static void as_put_io_context(struct as_rq *arq)
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*/
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#define RQ_RB_ROOT(ad, rq) (&(ad)->sort_list[rq_is_sync((rq))])
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static void as_add_arq_rb(struct as_data *ad, struct request *rq)
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static void as_add_rq_rb(struct as_data *ad, struct request *rq)
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{
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struct request *alias;
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while ((unlikely(alias = elv_rb_add(RQ_RB_ROOT(ad, rq), rq)))) {
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as_move_to_dispatch(ad, RQ_DATA(alias));
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as_move_to_dispatch(ad, alias);
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as_antic_stop(ad);
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}
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}
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static inline void as_del_arq_rb(struct as_data *ad, struct request *rq)
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static inline void as_del_rq_rb(struct as_data *ad, struct request *rq)
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{
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elv_rb_del(RQ_RB_ROOT(ad, rq), rq);
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}
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@ -285,26 +276,26 @@ static inline void as_del_arq_rb(struct as_data *ad, struct request *rq)
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* as_choose_req selects the preferred one of two requests of the same data_dir
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* ignoring time - eg. timeouts, which is the job of as_dispatch_request
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*/
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static struct as_rq *
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as_choose_req(struct as_data *ad, struct as_rq *arq1, struct as_rq *arq2)
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static struct request *
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as_choose_req(struct as_data *ad, struct request *rq1, struct request *rq2)
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{
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int data_dir;
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sector_t last, s1, s2, d1, d2;
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int r1_wrap=0, r2_wrap=0; /* requests are behind the disk head */
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const sector_t maxback = MAXBACK;
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if (arq1 == NULL || arq1 == arq2)
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return arq2;
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if (arq2 == NULL)
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return arq1;
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if (rq1 == NULL || rq1 == rq2)
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return rq2;
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if (rq2 == NULL)
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return rq1;
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data_dir = rq_is_sync(arq1->request);
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data_dir = rq_is_sync(rq1);
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last = ad->last_sector[data_dir];
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s1 = arq1->request->sector;
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s2 = arq2->request->sector;
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s1 = rq1->sector;
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s2 = rq2->sector;
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BUG_ON(data_dir != rq_is_sync(arq2->request));
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BUG_ON(data_dir != rq_is_sync(rq2));
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/*
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* Strict one way elevator _except_ in the case where we allow
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@ -331,55 +322,55 @@ as_choose_req(struct as_data *ad, struct as_rq *arq1, struct as_rq *arq2)
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/* Found required data */
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if (!r1_wrap && r2_wrap)
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return arq1;
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return rq1;
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else if (!r2_wrap && r1_wrap)
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return arq2;
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return rq2;
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else if (r1_wrap && r2_wrap) {
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/* both behind the head */
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if (s1 <= s2)
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return arq1;
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return rq1;
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else
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return arq2;
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return rq2;
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}
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/* Both requests in front of the head */
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if (d1 < d2)
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return arq1;
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return rq1;
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else if (d2 < d1)
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return arq2;
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return rq2;
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else {
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if (s1 >= s2)
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return arq1;
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return rq1;
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else
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return arq2;
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return rq2;
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}
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}
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/*
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* as_find_next_arq finds the next request after @prev in elevator order.
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* as_find_next_rq finds the next request after @prev in elevator order.
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* this with as_choose_req form the basis for how the scheduler chooses
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* what request to process next. Anticipation works on top of this.
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*/
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static struct as_rq *as_find_next_arq(struct as_data *ad, struct as_rq *arq)
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static struct request *
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as_find_next_rq(struct as_data *ad, struct request *last)
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{
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struct request *last = arq->request;
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struct rb_node *rbnext = rb_next(&last->rb_node);
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struct rb_node *rbprev = rb_prev(&last->rb_node);
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struct as_rq *next = NULL, *prev = NULL;
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struct request *next = NULL, *prev = NULL;
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BUG_ON(RB_EMPTY_NODE(&last->rb_node));
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if (rbprev)
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prev = RQ_DATA(rb_entry_rq(rbprev));
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prev = rb_entry_rq(rbprev);
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if (rbnext)
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next = RQ_DATA(rb_entry_rq(rbnext));
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next = rb_entry_rq(rbnext);
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else {
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const int data_dir = rq_is_sync(last);
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rbnext = rb_first(&ad->sort_list[data_dir]);
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if (rbnext && rbnext != &last->rb_node)
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next = RQ_DATA(rb_entry_rq(rbnext));
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next = rb_entry_rq(rbnext);
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}
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return as_choose_req(ad, next, prev);
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@ -575,11 +566,11 @@ static void as_update_iohist(struct as_data *ad, struct as_io_context *aic,
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* previous one issued.
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*/
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static int as_close_req(struct as_data *ad, struct as_io_context *aic,
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struct as_rq *arq)
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struct request *rq)
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{
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unsigned long delay; /* milliseconds */
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sector_t last = ad->last_sector[ad->batch_data_dir];
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sector_t next = arq->request->sector;
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sector_t next = rq->sector;
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sector_t delta; /* acceptable close offset (in sectors) */
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sector_t s;
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@ -636,7 +627,7 @@ static int as_close_req(struct as_data *ad, struct as_io_context *aic,
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*
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* If this task has queued some other IO, do not enter enticipation.
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*/
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static int as_can_break_anticipation(struct as_data *ad, struct as_rq *arq)
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static int as_can_break_anticipation(struct as_data *ad, struct request *rq)
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{
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struct io_context *ioc;
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struct as_io_context *aic;
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@ -644,7 +635,7 @@ static int as_can_break_anticipation(struct as_data *ad, struct as_rq *arq)
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ioc = ad->io_context;
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BUG_ON(!ioc);
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if (arq && ioc == arq->io_context) {
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if (rq && ioc == RQ_IOC(rq)) {
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/* request from same process */
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return 1;
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}
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@ -671,7 +662,7 @@ static int as_can_break_anticipation(struct as_data *ad, struct as_rq *arq)
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return 1;
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}
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if (arq && rq_is_sync(arq->request) && as_close_req(ad, aic, arq)) {
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if (rq && rq_is_sync(rq) && as_close_req(ad, aic, rq)) {
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/*
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* Found a close request that is not one of ours.
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*
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@ -687,7 +678,7 @@ static int as_can_break_anticipation(struct as_data *ad, struct as_rq *arq)
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ad->exit_no_coop = (7*ad->exit_no_coop)/8;
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}
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as_update_iohist(ad, aic, arq->request);
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as_update_iohist(ad, aic, rq);
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return 1;
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}
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@ -714,10 +705,10 @@ static int as_can_break_anticipation(struct as_data *ad, struct as_rq *arq)
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}
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/*
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* as_can_anticipate indicates whether we should either run arq
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* as_can_anticipate indicates whether we should either run rq
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* or keep anticipating a better request.
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*/
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static int as_can_anticipate(struct as_data *ad, struct as_rq *arq)
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static int as_can_anticipate(struct as_data *ad, struct request *rq)
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{
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if (!ad->io_context)
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/*
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@ -731,7 +722,7 @@ static int as_can_anticipate(struct as_data *ad, struct as_rq *arq)
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*/
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return 0;
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if (as_can_break_anticipation(ad, arq))
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if (as_can_break_anticipation(ad, rq))
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/*
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* This request is a good candidate. Don't keep anticipating,
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* run it.
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@ -749,16 +740,16 @@ static int as_can_anticipate(struct as_data *ad, struct as_rq *arq)
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}
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/*
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* as_update_arq must be called whenever a request (arq) is added to
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* as_update_rq must be called whenever a request (rq) is added to
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* the sort_list. This function keeps caches up to date, and checks if the
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* request might be one we are "anticipating"
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*/
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static void as_update_arq(struct as_data *ad, struct as_rq *arq)
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static void as_update_rq(struct as_data *ad, struct request *rq)
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{
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const int data_dir = rq_is_sync(arq->request);
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const int data_dir = rq_is_sync(rq);
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/* keep the next_arq cache up to date */
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ad->next_arq[data_dir] = as_choose_req(ad, arq, ad->next_arq[data_dir]);
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/* keep the next_rq cache up to date */
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ad->next_rq[data_dir] = as_choose_req(ad, rq, ad->next_rq[data_dir]);
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/*
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* have we been anticipating this request?
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@ -767,7 +758,7 @@ static void as_update_arq(struct as_data *ad, struct as_rq *arq)
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*/
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if (ad->antic_status == ANTIC_WAIT_REQ
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|| ad->antic_status == ANTIC_WAIT_NEXT) {
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if (as_can_break_anticipation(ad, arq))
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if (as_can_break_anticipation(ad, rq))
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as_antic_stop(ad);
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}
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}
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@ -807,12 +798,11 @@ static void update_write_batch(struct as_data *ad)
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static void as_completed_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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WARN_ON(!list_empty(&rq->queuelist));
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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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if (RQ_STATE(rq) != AS_RQ_REMOVED) {
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printk("rq->state %d\n", RQ_STATE(rq));
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WARN_ON(1);
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goto out;
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}
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@ -839,7 +829,7 @@ static void as_completed_request(request_queue_t *q, struct request *rq)
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ad->new_batch = 0;
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}
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if (ad->io_context == arq->io_context && ad->io_context) {
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if (ad->io_context == RQ_IOC(rq) && ad->io_context) {
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ad->antic_start = jiffies;
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ad->ioc_finished = 1;
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if (ad->antic_status == ANTIC_WAIT_REQ) {
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@ -851,9 +841,9 @@ static void as_completed_request(request_queue_t *q, struct request *rq)
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}
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}
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as_put_io_context(arq);
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as_put_io_context(rq);
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out:
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arq->state = AS_RQ_POSTSCHED;
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RQ_SET_STATE(rq, AS_RQ_POSTSCHED);
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}
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/*
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@ -864,26 +854,27 @@ out:
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*/
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static void as_remove_queued_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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const int data_dir = rq_is_sync(rq);
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struct as_data *ad = q->elevator->elevator_data;
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struct io_context *ioc;
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WARN_ON(arq->state != AS_RQ_QUEUED);
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WARN_ON(RQ_STATE(rq) != AS_RQ_QUEUED);
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if (arq->io_context && arq->io_context->aic) {
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BUG_ON(!atomic_read(&arq->io_context->aic->nr_queued));
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atomic_dec(&arq->io_context->aic->nr_queued);
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ioc = RQ_IOC(rq);
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if (ioc && ioc->aic) {
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BUG_ON(!atomic_read(&ioc->aic->nr_queued));
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atomic_dec(&ioc->aic->nr_queued);
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}
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/*
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* Update the "next_arq" cache if we are about to remove its
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* Update the "next_rq" cache if we are about to remove its
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* entry
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*/
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if (ad->next_arq[data_dir] == arq)
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ad->next_arq[data_dir] = as_find_next_arq(ad, arq);
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if (ad->next_rq[data_dir] == rq)
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ad->next_rq[data_dir] = as_find_next_rq(ad, rq);
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rq_fifo_clear(rq);
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as_del_arq_rb(ad, rq);
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as_del_rq_rb(ad, rq);
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}
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/*
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@ -935,9 +926,8 @@ static inline int as_batch_expired(struct as_data *ad)
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/*
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* move an entry to dispatch queue
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*/
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static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
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static void as_move_to_dispatch(struct as_data *ad, struct request *rq)
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{
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struct request *rq = arq->request;
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const int data_dir = rq_is_sync(rq);
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BUG_ON(RB_EMPTY_NODE(&rq->rb_node));
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@ -947,13 +937,14 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
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/*
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* This has to be set in order to be correctly updated by
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* as_find_next_arq
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* as_find_next_rq
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*/
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ad->last_sector[data_dir] = rq->sector + rq->nr_sectors;
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if (data_dir == REQ_SYNC) {
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struct io_context *ioc = RQ_IOC(rq);
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/* In case we have to anticipate after this */
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copy_io_context(&ad->io_context, &arq->io_context);
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copy_io_context(&ad->io_context, &ioc);
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} else {
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if (ad->io_context) {
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put_io_context(ad->io_context);
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@ -965,19 +956,19 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
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}
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ad->ioc_finished = 0;
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ad->next_arq[data_dir] = as_find_next_arq(ad, arq);
|
||||
ad->next_rq[data_dir] = as_find_next_rq(ad, rq);
|
||||
|
||||
/*
|
||||
* take it off the sort and fifo list, add to dispatch queue
|
||||
*/
|
||||
as_remove_queued_request(ad->q, rq);
|
||||
WARN_ON(arq->state != AS_RQ_QUEUED);
|
||||
WARN_ON(RQ_STATE(rq) != AS_RQ_QUEUED);
|
||||
|
||||
elv_dispatch_sort(ad->q, rq);
|
||||
|
||||
arq->state = AS_RQ_DISPATCHED;
|
||||
if (arq->io_context && arq->io_context->aic)
|
||||
atomic_inc(&arq->io_context->aic->nr_dispatched);
|
||||
RQ_SET_STATE(rq, AS_RQ_DISPATCHED);
|
||||
if (RQ_IOC(rq) && RQ_IOC(rq)->aic)
|
||||
atomic_inc(&RQ_IOC(rq)->aic->nr_dispatched);
|
||||
ad->nr_dispatched++;
|
||||
}
|
||||
|
||||
|
|
@ -989,9 +980,9 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
|
|||
static int as_dispatch_request(request_queue_t *q, int force)
|
||||
{
|
||||
struct as_data *ad = q->elevator->elevator_data;
|
||||
struct as_rq *arq;
|
||||
const int reads = !list_empty(&ad->fifo_list[REQ_SYNC]);
|
||||
const int writes = !list_empty(&ad->fifo_list[REQ_ASYNC]);
|
||||
struct request *rq;
|
||||
|
||||
if (unlikely(force)) {
|
||||
/*
|
||||
|
|
@ -1007,14 +998,14 @@ static int as_dispatch_request(request_queue_t *q, int force)
|
|||
ad->changed_batch = 0;
|
||||
ad->new_batch = 0;
|
||||
|
||||
while (ad->next_arq[REQ_SYNC]) {
|
||||
as_move_to_dispatch(ad, ad->next_arq[REQ_SYNC]);
|
||||
while (ad->next_rq[REQ_SYNC]) {
|
||||
as_move_to_dispatch(ad, ad->next_rq[REQ_SYNC]);
|
||||
dispatched++;
|
||||
}
|
||||
ad->last_check_fifo[REQ_SYNC] = jiffies;
|
||||
|
||||
while (ad->next_arq[REQ_ASYNC]) {
|
||||
as_move_to_dispatch(ad, ad->next_arq[REQ_ASYNC]);
|
||||
while (ad->next_rq[REQ_ASYNC]) {
|
||||
as_move_to_dispatch(ad, ad->next_rq[REQ_ASYNC]);
|
||||
dispatched++;
|
||||
}
|
||||
ad->last_check_fifo[REQ_ASYNC] = jiffies;
|
||||
|
|
@ -1038,19 +1029,19 @@ static int as_dispatch_request(request_queue_t *q, int force)
|
|||
/*
|
||||
* batch is still running or no reads or no writes
|
||||
*/
|
||||
arq = ad->next_arq[ad->batch_data_dir];
|
||||
rq = ad->next_rq[ad->batch_data_dir];
|
||||
|
||||
if (ad->batch_data_dir == REQ_SYNC && ad->antic_expire) {
|
||||
if (as_fifo_expired(ad, REQ_SYNC))
|
||||
goto fifo_expired;
|
||||
|
||||
if (as_can_anticipate(ad, arq)) {
|
||||
if (as_can_anticipate(ad, rq)) {
|
||||
as_antic_waitreq(ad);
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
if (arq) {
|
||||
if (rq) {
|
||||
/* we have a "next request" */
|
||||
if (reads && !writes)
|
||||
ad->current_batch_expires =
|
||||
|
|
@ -1078,7 +1069,7 @@ static int as_dispatch_request(request_queue_t *q, int force)
|
|||
ad->changed_batch = 1;
|
||||
}
|
||||
ad->batch_data_dir = REQ_SYNC;
|
||||
arq = RQ_DATA(rq_entry_fifo(ad->fifo_list[REQ_SYNC].next));
|
||||
rq = rq_entry_fifo(ad->fifo_list[REQ_SYNC].next);
|
||||
ad->last_check_fifo[ad->batch_data_dir] = jiffies;
|
||||
goto dispatch_request;
|
||||
}
|
||||
|
|
@ -1104,7 +1095,7 @@ dispatch_writes:
|
|||
ad->batch_data_dir = REQ_ASYNC;
|
||||
ad->current_write_count = ad->write_batch_count;
|
||||
ad->write_batch_idled = 0;
|
||||
arq = ad->next_arq[ad->batch_data_dir];
|
||||
rq = ad->next_rq[ad->batch_data_dir];
|
||||
goto dispatch_request;
|
||||
}
|
||||
|
||||
|
|
@ -1118,7 +1109,7 @@ dispatch_request:
|
|||
|
||||
if (as_fifo_expired(ad, ad->batch_data_dir)) {
|
||||
fifo_expired:
|
||||
arq = RQ_DATA(rq_entry_fifo(ad->fifo_list[ad->batch_data_dir].next));
|
||||
rq = rq_entry_fifo(ad->fifo_list[ad->batch_data_dir].next);
|
||||
}
|
||||
|
||||
if (ad->changed_batch) {
|
||||
|
|
@ -1137,34 +1128,33 @@ fifo_expired:
|
|||
}
|
||||
|
||||
/*
|
||||
* arq is the selected appropriate request.
|
||||
* rq is the selected appropriate request.
|
||||
*/
|
||||
as_move_to_dispatch(ad, arq);
|
||||
as_move_to_dispatch(ad, rq);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* add arq to rbtree and fifo
|
||||
* add rq to rbtree and fifo
|
||||
*/
|
||||
static void as_add_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct as_data *ad = q->elevator->elevator_data;
|
||||
struct as_rq *arq = RQ_DATA(rq);
|
||||
int data_dir;
|
||||
|
||||
arq->state = AS_RQ_NEW;
|
||||
RQ_SET_STATE(rq, AS_RQ_NEW);
|
||||
|
||||
data_dir = rq_is_sync(rq);
|
||||
|
||||
arq->io_context = as_get_io_context();
|
||||
rq->elevator_private = as_get_io_context();
|
||||
|
||||
if (arq->io_context) {
|
||||
as_update_iohist(ad, arq->io_context->aic, arq->request);
|
||||
atomic_inc(&arq->io_context->aic->nr_queued);
|
||||
if (RQ_IOC(rq)) {
|
||||
as_update_iohist(ad, RQ_IOC(rq)->aic, rq);
|
||||
atomic_inc(&RQ_IOC(rq)->aic->nr_queued);
|
||||
}
|
||||
|
||||
as_add_arq_rb(ad, rq);
|
||||
as_add_rq_rb(ad, rq);
|
||||
|
||||
/*
|
||||
* set expire time (only used for reads) and add to fifo list
|
||||
|
|
@ -1172,28 +1162,24 @@ static void as_add_request(request_queue_t *q, struct request *rq)
|
|||
rq_set_fifo_time(rq, jiffies + ad->fifo_expire[data_dir]);
|
||||
list_add_tail(&rq->queuelist, &ad->fifo_list[data_dir]);
|
||||
|
||||
as_update_arq(ad, arq); /* keep state machine up to date */
|
||||
arq->state = AS_RQ_QUEUED;
|
||||
as_update_rq(ad, rq); /* keep state machine up to date */
|
||||
RQ_SET_STATE(rq, AS_RQ_QUEUED);
|
||||
}
|
||||
|
||||
static void as_activate_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct as_rq *arq = RQ_DATA(rq);
|
||||
|
||||
WARN_ON(arq->state != AS_RQ_DISPATCHED);
|
||||
arq->state = AS_RQ_REMOVED;
|
||||
if (arq->io_context && arq->io_context->aic)
|
||||
atomic_dec(&arq->io_context->aic->nr_dispatched);
|
||||
WARN_ON(RQ_STATE(rq) != AS_RQ_DISPATCHED);
|
||||
RQ_SET_STATE(rq, AS_RQ_REMOVED);
|
||||
if (RQ_IOC(rq) && RQ_IOC(rq)->aic)
|
||||
atomic_dec(&RQ_IOC(rq)->aic->nr_dispatched);
|
||||
}
|
||||
|
||||
static void as_deactivate_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct as_rq *arq = RQ_DATA(rq);
|
||||
|
||||
WARN_ON(arq->state != AS_RQ_REMOVED);
|
||||
arq->state = AS_RQ_DISPATCHED;
|
||||
if (arq->io_context && arq->io_context->aic)
|
||||
atomic_inc(&arq->io_context->aic->nr_dispatched);
|
||||
WARN_ON(RQ_STATE(rq) != AS_RQ_REMOVED);
|
||||
RQ_SET_STATE(rq, AS_RQ_DISPATCHED);
|
||||
if (RQ_IOC(rq) && RQ_IOC(rq)->aic)
|
||||
atomic_inc(&RQ_IOC(rq)->aic->nr_dispatched);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -1237,8 +1223,8 @@ static void as_merged_request(request_queue_t *q, struct request *req, int type)
|
|||
* if the merge was a front merge, we need to reposition request
|
||||
*/
|
||||
if (type == ELEVATOR_FRONT_MERGE) {
|
||||
as_del_arq_rb(ad, req);
|
||||
as_add_arq_rb(ad, req);
|
||||
as_del_rq_rb(ad, req);
|
||||
as_add_rq_rb(ad, req);
|
||||
/*
|
||||
* Note! At this stage of this and the next function, our next
|
||||
* request may not be optimal - eg the request may have "grown"
|
||||
|
|
@ -1250,25 +1236,22 @@ static void as_merged_request(request_queue_t *q, struct request *req, int type)
|
|||
static void as_merged_requests(request_queue_t *q, struct request *req,
|
||||
struct request *next)
|
||||
{
|
||||
struct as_rq *arq = RQ_DATA(req);
|
||||
struct as_rq *anext = RQ_DATA(next);
|
||||
|
||||
BUG_ON(!arq);
|
||||
BUG_ON(!anext);
|
||||
|
||||
/*
|
||||
* if anext expires before arq, assign its expire time to arq
|
||||
* and move into anext position (anext will be deleted) in fifo
|
||||
* if next expires before rq, assign its expire time to arq
|
||||
* and move into next position (next will be deleted) in fifo
|
||||
*/
|
||||
if (!list_empty(&req->queuelist) && !list_empty(&next->queuelist)) {
|
||||
if (time_before(rq_fifo_time(next), rq_fifo_time(req))) {
|
||||
struct io_context *rioc = RQ_IOC(req);
|
||||
struct io_context *nioc = RQ_IOC(next);
|
||||
|
||||
list_move(&req->queuelist, &next->queuelist);
|
||||
rq_set_fifo_time(req, rq_fifo_time(next));
|
||||
/*
|
||||
* Don't copy here but swap, because when anext is
|
||||
* removed below, it must contain the unused context
|
||||
*/
|
||||
swap_io_context(&arq->io_context, &anext->io_context);
|
||||
swap_io_context(&rioc, &nioc);
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -1276,9 +1259,9 @@ static void as_merged_requests(request_queue_t *q, struct request *req,
|
|||
* kill knowledge of next, this one is a goner
|
||||
*/
|
||||
as_remove_queued_request(q, next);
|
||||
as_put_io_context(anext);
|
||||
as_put_io_context(next);
|
||||
|
||||
anext->state = AS_RQ_MERGED;
|
||||
RQ_SET_STATE(next, AS_RQ_MERGED);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -1301,45 +1284,6 @@ static void as_work_handler(void *data)
|
|||
spin_unlock_irqrestore(q->queue_lock, flags);
|
||||
}
|
||||
|
||||
static void as_put_request(request_queue_t *q, struct request *rq)
|
||||
{
|
||||
struct as_data *ad = q->elevator->elevator_data;
|
||||
struct as_rq *arq = RQ_DATA(rq);
|
||||
|
||||
if (!arq) {
|
||||
WARN_ON(1);
|
||||
return;
|
||||
}
|
||||
|
||||
if (unlikely(arq->state != AS_RQ_POSTSCHED &&
|
||||
arq->state != AS_RQ_PRESCHED &&
|
||||
arq->state != AS_RQ_MERGED)) {
|
||||
printk("arq->state %d\n", arq->state);
|
||||
WARN_ON(1);
|
||||
}
|
||||
|
||||
mempool_free(arq, ad->arq_pool);
|
||||
rq->elevator_private = NULL;
|
||||
}
|
||||
|
||||
static int as_set_request(request_queue_t *q, struct request *rq,
|
||||
struct bio *bio, gfp_t gfp_mask)
|
||||
{
|
||||
struct as_data *ad = q->elevator->elevator_data;
|
||||
struct as_rq *arq = mempool_alloc(ad->arq_pool, gfp_mask);
|
||||
|
||||
if (arq) {
|
||||
memset(arq, 0, sizeof(*arq));
|
||||
arq->request = rq;
|
||||
arq->state = AS_RQ_PRESCHED;
|
||||
arq->io_context = NULL;
|
||||
rq->elevator_private = arq;
|
||||
return 0;
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int as_may_queue(request_queue_t *q, int rw, struct bio *bio)
|
||||
{
|
||||
int ret = ELV_MQUEUE_MAY;
|
||||
|
|
@ -1366,22 +1310,17 @@ static void as_exit_queue(elevator_t *e)
|
|||
BUG_ON(!list_empty(&ad->fifo_list[REQ_SYNC]));
|
||||
BUG_ON(!list_empty(&ad->fifo_list[REQ_ASYNC]));
|
||||
|
||||
mempool_destroy(ad->arq_pool);
|
||||
put_io_context(ad->io_context);
|
||||
kfree(ad);
|
||||
}
|
||||
|
||||
/*
|
||||
* initialize elevator private data (as_data), and alloc a arq for
|
||||
* each request on the free lists
|
||||
* initialize elevator private data (as_data).
|
||||
*/
|
||||
static void *as_init_queue(request_queue_t *q, elevator_t *e)
|
||||
{
|
||||
struct as_data *ad;
|
||||
|
||||
if (!arq_pool)
|
||||
return NULL;
|
||||
|
||||
ad = kmalloc_node(sizeof(*ad), GFP_KERNEL, q->node);
|
||||
if (!ad)
|
||||
return NULL;
|
||||
|
|
@ -1389,13 +1328,6 @@ static void *as_init_queue(request_queue_t *q, elevator_t *e)
|
|||
|
||||
ad->q = q; /* Identify what queue the data belongs to */
|
||||
|
||||
ad->arq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab,
|
||||
mempool_free_slab, arq_pool, q->node);
|
||||
if (!ad->arq_pool) {
|
||||
kfree(ad);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* anticipatory scheduling helpers */
|
||||
ad->antic_timer.function = as_antic_timeout;
|
||||
ad->antic_timer.data = (unsigned long)q;
|
||||
|
|
@ -1516,8 +1448,6 @@ static struct elevator_type iosched_as = {
|
|||
.elevator_completed_req_fn = as_completed_request,
|
||||
.elevator_former_req_fn = elv_rb_former_request,
|
||||
.elevator_latter_req_fn = elv_rb_latter_request,
|
||||
.elevator_set_req_fn = as_set_request,
|
||||
.elevator_put_req_fn = as_put_request,
|
||||
.elevator_may_queue_fn = as_may_queue,
|
||||
.elevator_init_fn = as_init_queue,
|
||||
.elevator_exit_fn = as_exit_queue,
|
||||
|
|
@ -1533,11 +1463,6 @@ static int __init as_init(void)
|
|||
{
|
||||
int ret;
|
||||
|
||||
arq_pool = kmem_cache_create("as_arq", sizeof(struct as_rq),
|
||||
0, 0, NULL, NULL);
|
||||
if (!arq_pool)
|
||||
return -ENOMEM;
|
||||
|
||||
ret = elv_register(&iosched_as);
|
||||
if (!ret) {
|
||||
/*
|
||||
|
|
@ -1549,7 +1474,6 @@ static int __init as_init(void)
|
|||
return 0;
|
||||
}
|
||||
|
||||
kmem_cache_destroy(arq_pool);
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
|
@ -1563,7 +1487,6 @@ static void __exit as_exit(void)
|
|||
if (atomic_read(&ioc_count))
|
||||
wait_for_completion(ioc_gone);
|
||||
synchronize_rcu();
|
||||
kmem_cache_destroy(arq_pool);
|
||||
}
|
||||
|
||||
module_init(as_init);
|
||||
|
|
|
|||
Loading…
Reference in New Issue