From 71539717c10521114403d27e171c9cbe35dcd900 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 3 Nov 2021 05:52:45 -0600 Subject: block: split request allocation components into helpers This is in preparation for a fix, but serves as a cleanup as well moving the cached vs regular alloc logic out of blk_mq_submit_bio(). Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq.c | 71 +++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 48 insertions(+), 23 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index 5498454c2164..dcb413297a96 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2478,6 +2478,51 @@ static inline unsigned short blk_plug_max_rq_count(struct blk_plug *plug) return BLK_MAX_REQUEST_COUNT; } +static struct request *blk_mq_get_new_requests(struct request_queue *q, + struct blk_plug *plug, + struct bio *bio) +{ + struct blk_mq_alloc_data data = { + .q = q, + .nr_tags = 1, + .cmd_flags = bio->bi_opf, + }; + struct request *rq; + + if (plug) { + data.nr_tags = plug->nr_ios; + plug->nr_ios = 1; + data.cached_rq = &plug->cached_rq; + } + + rq = __blk_mq_alloc_requests(&data); + if (rq) + return rq; + + rq_qos_cleanup(q, bio); + if (bio->bi_opf & REQ_NOWAIT) + bio_wouldblock_error(bio); + return NULL; +} + +static inline struct request *blk_mq_get_request(struct request_queue *q, + struct blk_plug *plug, + struct bio *bio) +{ + if (plug) { + struct request *rq; + + rq = rq_list_peek(&plug->cached_rq); + if (rq) { + plug->cached_rq = rq_list_next(rq); + INIT_LIST_HEAD(&rq->queuelist); + return rq; + } + } + + return blk_mq_get_new_requests(q, plug, bio); +} + /** * blk_mq_submit_bio - Create and send a request to block device. * @bio: Bio pointer. @@ -2518,29 +2563,9 @@ void blk_mq_submit_bio(struct bio *bio) rq_qos_throttle(q, bio); plug = blk_mq_plug(q, bio); - if (plug && plug->cached_rq) { - rq = rq_list_pop(&plug->cached_rq); - INIT_LIST_HEAD(&rq->queuelist); - } else { - struct blk_mq_alloc_data data = { - .q = q, - .nr_tags = 1, - .cmd_flags = bio->bi_opf, - }; - - if (plug) { - data.nr_tags = plug->nr_ios; - plug->nr_ios = 1; - data.cached_rq = &plug->cached_rq; - } - rq = __blk_mq_alloc_requests(&data); - if (unlikely(!rq)) { - rq_qos_cleanup(q, bio); - if (bio->bi_opf & REQ_NOWAIT) - bio_wouldblock_error(bio); - goto queue_exit; - } - } + rq = blk_mq_get_request(q, plug, bio); + if (unlikely(!rq)) + goto queue_exit; trace_block_getrq(bio); -- cgit v1.2.3