diff options
Diffstat (limited to 'drivers/block/elevator.c')
| -rw-r--r-- | drivers/block/elevator.c | 43 |
1 files changed, 18 insertions, 25 deletions
diff --git a/drivers/block/elevator.c b/drivers/block/elevator.c index 29d6c8237ab3..415144372c75 100644 --- a/drivers/block/elevator.c +++ b/drivers/block/elevator.c @@ -83,15 +83,6 @@ inline int elv_try_merge(struct request *__rq, struct bio *bio) } EXPORT_SYMBOL(elv_try_merge); -inline int elv_try_last_merge(request_queue_t *q, struct bio *bio) -{ - if (q->last_merge) - return elv_try_merge(q->last_merge, bio); - - return ELEVATOR_NO_MERGE; -} -EXPORT_SYMBOL(elv_try_last_merge); - static struct elevator_type *elevator_find(const char *name) { struct elevator_type *e = NULL; @@ -239,6 +230,9 @@ void elv_dispatch_sort(request_queue_t *q, struct request *rq) unsigned max_back; struct list_head *entry; + if (q->last_merge == rq) + q->last_merge = NULL; + boundary = q->end_sector; max_back = q->max_back_kb * 2; boundary = boundary > max_back ? boundary - max_back : 0; @@ -265,6 +259,15 @@ void elv_dispatch_sort(request_queue_t *q, struct request *rq) int elv_merge(request_queue_t *q, struct request **req, struct bio *bio) { elevator_t *e = q->elevator; + int ret; + + if (q->last_merge) { + ret = elv_try_merge(q->last_merge, bio); + if (ret != ELEVATOR_NO_MERGE) { + *req = q->last_merge; + return ret; + } + } if (e->ops->elevator_merge_fn) return e->ops->elevator_merge_fn(q, req, bio); @@ -278,6 +281,8 @@ void elv_merged_request(request_queue_t *q, struct request *rq) if (e->ops->elevator_merged_fn) e->ops->elevator_merged_fn(q, rq); + + q->last_merge = rq; } void elv_merge_requests(request_queue_t *q, struct request *rq, @@ -285,11 +290,10 @@ void elv_merge_requests(request_queue_t *q, struct request *rq, { elevator_t *e = q->elevator; - if (q->last_merge == next) - q->last_merge = NULL; - if (e->ops->elevator_merge_req_fn) e->ops->elevator_merge_req_fn(q, rq, next); + + q->last_merge = rq; } void elv_requeue_request(request_queue_t *q, struct request *rq) @@ -384,6 +388,8 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where, BUG_ON(!blk_fs_request(rq)); rq->flags |= REQ_SORTED; q->elevator->ops->elevator_add_req_fn(q, rq); + if (q->last_merge == NULL && rq_mergeable(rq)) + q->last_merge = rq; break; default: @@ -462,9 +468,6 @@ struct request *elv_next_request(request_queue_t *q) rq->flags |= REQ_STARTED; } - if (rq == q->last_merge) - q->last_merge = NULL; - if (!q->boundary_rq || q->boundary_rq == rq) { q->end_sector = rq_end_sector(rq); q->boundary_rq = NULL; @@ -518,16 +521,6 @@ void elv_dequeue_request(request_queue_t *q, struct request *rq) */ if (blk_account_rq(rq)) q->in_flight++; - - /* - * the main clearing point for q->last_merge is on retrieval of - * request by driver (it calls elv_next_request()), but it _can_ - * also happen here if a request is added to the queue but later - * deleted without ever being given to driver (merged with another - * request). - */ - if (rq == q->last_merge) - q->last_merge = NULL; } int elv_queue_empty(request_queue_t *q) |