From 98b11471d72a374f346bec50a00d0887719b85b3 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 20 Oct 2005 16:46:54 +0200 Subject: [PATCH] [PATCH] 04/05 remove last_merge handling from ioscheds Remove last_merge handling from all ioscheds. This patch removes merging capability of noop iosched. Signed-off-by: Tejun Heo --- drivers/block/as-iosched.c | 35 ++++---------------------------- drivers/block/cfq-iosched.c | 26 ++---------------------- drivers/block/deadline-iosched.c | 30 ++------------------------- drivers/block/noop-iosched.c | 31 ---------------------------- 4 files changed, 8 insertions(+), 114 deletions(-) diff --git a/drivers/block/as-iosched.c b/drivers/block/as-iosched.c index 1775ffe9edc..5d20e4bcbc7 100644 --- a/drivers/block/as-iosched.c +++ b/drivers/block/as-iosched.c @@ -279,14 +279,6 @@ static inline void as_del_arq_hash(struct as_rq *arq) __as_del_arq_hash(arq); } -static void as_remove_merge_hints(request_queue_t *q, struct as_rq *arq) -{ - as_del_arq_hash(arq); - - if (q->last_merge == arq->request) - q->last_merge = NULL; -} - static void as_add_arq_hash(struct as_data *ad, struct as_rq *arq) { struct request *rq = arq->request; @@ -330,7 +322,7 @@ static struct request *as_find_arq_hash(struct as_data *ad, sector_t offset) BUG_ON(!arq->on_hash); if (!rq_mergeable(__rq)) { - as_remove_merge_hints(ad->q, arq); + as_del_arq_hash(arq); continue; } @@ -1040,7 +1032,7 @@ static void as_remove_queued_request(request_queue_t *q, struct request *rq) ad->next_arq[data_dir] = as_find_next_arq(ad, arq); list_del_init(&arq->fifo); - as_remove_merge_hints(q, arq); + as_del_arq_hash(arq); as_del_arq_rb(ad, arq); } @@ -1351,7 +1343,7 @@ as_add_aliased_request(struct as_data *ad, struct as_rq *arq, struct as_rq *alia /* * Don't want to have to handle merges. */ - as_remove_merge_hints(ad->q, arq); + as_del_arq_hash(arq); } /* @@ -1392,12 +1384,8 @@ static void as_add_request(request_queue_t *q, struct request *rq) arq->expires = jiffies + ad->fifo_expire[data_dir]; list_add_tail(&arq->fifo, &ad->fifo_list[data_dir]); - if (rq_mergeable(arq->request)) { + if (rq_mergeable(arq->request)) as_add_arq_hash(ad, arq); - - if (!ad->q->last_merge) - ad->q->last_merge = arq->request; - } as_update_arq(ad, arq); /* keep state machine up to date */ } else { @@ -1486,15 +1474,6 @@ as_merge(request_queue_t *q, struct request **req, struct bio *bio) struct request *__rq; int ret; - /* - * try last_merge to avoid going to hash - */ - ret = elv_try_last_merge(q, bio); - if (ret != ELEVATOR_NO_MERGE) { - __rq = q->last_merge; - goto out_insert; - } - /* * see if the merge hash can satisfy a back merge */ @@ -1523,9 +1502,6 @@ as_merge(request_queue_t *q, struct request **req, struct bio *bio) return ELEVATOR_NO_MERGE; out: - if (rq_mergeable(__rq)) - q->last_merge = __rq; -out_insert: if (ret) { if (rq_mergeable(__rq)) as_hot_arq_hash(ad, RQ_DATA(__rq)); @@ -1572,9 +1548,6 @@ static void as_merged_request(request_queue_t *q, struct request *req) * behind the disk head. We currently don't bother adjusting. */ } - - if (arq->on_hash) - q->last_merge = req; } static void diff --git a/drivers/block/cfq-iosched.c b/drivers/block/cfq-iosched.c index 7b14160e079..62a19ed0443 100644 --- a/drivers/block/cfq-iosched.c +++ b/drivers/block/cfq-iosched.c @@ -304,14 +304,6 @@ static inline void cfq_del_crq_hash(struct cfq_rq *crq) hlist_del_init(&crq->hash); } -static void cfq_remove_merge_hints(request_queue_t *q, struct cfq_rq *crq) -{ - cfq_del_crq_hash(crq); - - if (q->last_merge == crq->request) - q->last_merge = NULL; -} - static inline void cfq_add_crq_hash(struct cfq_data *cfqd, struct cfq_rq *crq) { const int hash_idx = CFQ_MHASH_FN(rq_hash_key(crq->request)); @@ -672,7 +664,7 @@ static void cfq_remove_request(struct request *rq) list_del_init(&rq->queuelist); cfq_del_crq_rb(crq); - cfq_remove_merge_hints(rq->q, crq); + cfq_del_crq_hash(crq); } static int @@ -682,12 +674,6 @@ cfq_merge(request_queue_t *q, struct request **req, struct bio *bio) struct request *__rq; int ret; - ret = elv_try_last_merge(q, bio); - if (ret != ELEVATOR_NO_MERGE) { - __rq = q->last_merge; - goto out_insert; - } - __rq = cfq_find_rq_hash(cfqd, bio->bi_sector); if (__rq && elv_rq_merge_ok(__rq, bio)) { ret = ELEVATOR_BACK_MERGE; @@ -702,8 +688,6 @@ cfq_merge(request_queue_t *q, struct request **req, struct bio *bio) return ELEVATOR_NO_MERGE; out: - q->last_merge = __rq; -out_insert: *req = __rq; return ret; } @@ -722,8 +706,6 @@ static void cfq_merged_request(request_queue_t *q, struct request *req) cfq_update_next_crq(crq); cfq_reposition_crq_rb(cfqq, crq); } - - q->last_merge = req; } static void @@ -1670,13 +1652,9 @@ static void cfq_insert_request(request_queue_t *q, struct request *rq) list_add_tail(&rq->queuelist, &cfqq->fifo); - if (rq_mergeable(rq)) { + if (rq_mergeable(rq)) cfq_add_crq_hash(cfqd, crq); - if (!cfqd->queue->last_merge) - cfqd->queue->last_merge = rq; - } - cfq_crq_enqueued(cfqd, cfqq, crq); } diff --git a/drivers/block/deadline-iosched.c b/drivers/block/deadline-iosched.c index 07de4d24ddb..43d93155efb 100644 --- a/drivers/block/deadline-iosched.c +++ b/drivers/block/deadline-iosched.c @@ -112,15 +112,6 @@ static inline void deadline_del_drq_hash(struct deadline_rq *drq) __deadline_del_drq_hash(drq); } -static void -deadline_remove_merge_hints(request_queue_t *q, struct deadline_rq *drq) -{ - deadline_del_drq_hash(drq); - - if (q->last_merge == drq->request) - q->last_merge = NULL; -} - static inline void deadline_add_drq_hash(struct deadline_data *dd, struct deadline_rq *drq) { @@ -299,12 +290,8 @@ deadline_add_request(struct request_queue *q, struct request *rq) drq->expires = jiffies + dd->fifo_expire[data_dir]; list_add_tail(&drq->fifo, &dd->fifo_list[data_dir]); - if (rq_mergeable(rq)) { + if (rq_mergeable(rq)) deadline_add_drq_hash(dd, drq); - - if (!q->last_merge) - q->last_merge = rq; - } } /* @@ -316,8 +303,8 @@ static void deadline_remove_request(request_queue_t *q, struct request *rq) 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); + deadline_del_drq_hash(drq); } static int @@ -327,15 +314,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio) struct request *__rq; int ret; - /* - * try last_merge to avoid going to hash - */ - ret = elv_try_last_merge(q, bio); - if (ret != ELEVATOR_NO_MERGE) { - __rq = q->last_merge; - goto out_insert; - } - /* * see if the merge hash can satisfy a back merge */ @@ -368,8 +346,6 @@ deadline_merge(request_queue_t *q, struct request **req, struct bio *bio) return ELEVATOR_NO_MERGE; out: - q->last_merge = __rq; -out_insert: if (ret) deadline_hot_drq_hash(dd, RQ_DATA(__rq)); *req = __rq; @@ -394,8 +370,6 @@ static void deadline_merged_request(request_queue_t *q, struct request *req) deadline_del_drq_rb(dd, drq); deadline_add_drq_rb(dd, drq); } - - q->last_merge = req; } static void diff --git a/drivers/block/noop-iosched.c b/drivers/block/noop-iosched.c index bc2252b6f2e..f56b8edb06e 100644 --- a/drivers/block/noop-iosched.c +++ b/drivers/block/noop-iosched.c @@ -7,38 +7,9 @@ #include #include -/* - * See if we can find a request that this buffer can be coalesced with. - */ -static int elevator_noop_merge(request_queue_t *q, struct request **req, - struct bio *bio) -{ - int ret; - - ret = elv_try_last_merge(q, bio); - if (ret != ELEVATOR_NO_MERGE) - *req = q->last_merge; - - return ret; -} - -static void elevator_noop_merge_requests(request_queue_t *q, struct request *req, - struct request *next) -{ - list_del_init(&next->queuelist); -} - static void elevator_noop_add_request(request_queue_t *q, struct request *rq) { elv_dispatch_add_tail(q, rq); - - /* - * new merges must not precede this barrier - */ - if (rq->flags & REQ_HARDBARRIER) - q->last_merge = NULL; - else if (!q->last_merge) - q->last_merge = rq; } static int elevator_noop_dispatch(request_queue_t *q, int force) @@ -48,8 +19,6 @@ static int elevator_noop_dispatch(request_queue_t *q, int force) static struct elevator_type elevator_noop = { .ops = { - .elevator_merge_fn = elevator_noop_merge, - .elevator_merge_req_fn = elevator_noop_merge_requests, .elevator_dispatch_fn = elevator_noop_dispatch, .elevator_add_req_fn = elevator_noop_add_request, }, -- 2.20.1