Commit 5f550ede authored by Jan Kara's avatar Jan Kara Committed by Jens Axboe
Browse files

bfq: Remove pointless bfq_init_rq() calls 



We call bfq_init_rq() from request merging functions where requests we
get should have already gone through bfq_init_rq() during insert and
anyway we want to do anything only if the request is already tracked by
BFQ. So replace calls to bfq_init_rq() with RQ_BFQQ() instead to simply
skip requests untracked by BFQ. We move bfq_init_rq() call in
bfq_insert_request() a bit earlier to cover request merging and thus
can transfer FIFO position in case of a merge.

CC: stable@vger.kernel.org
Tested-by: default avatar"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-6-jack@suse.cz


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent fc84e1f9

block/bfq-iosched.c

+6 −6
Original line number Diff line number Diff line
@@ -2497,8 +2497,6 @@ static int bfq_request_merge(struct request_queue *q, struct request **req, 
	return ELEVATOR_NO_MERGE;

}



static struct bfq_queue *bfq_init_rq(struct request *rq);



static void bfq_request_merged(struct request_queue *q, struct request *req,

			       enum elv_merge type)

{
@@ -2507,7 +2505,7 @@ static void bfq_request_merged(struct request_queue *q, struct request *req, 
	    blk_rq_pos(req) <

	    blk_rq_pos(container_of(rb_prev(&req->rb_node),

				    struct request, rb_node))) {

		struct bfq_queue *bfqq = bfq_init_rq(req);

		struct bfq_queue *bfqq = RQ_BFQQ(req);

		struct bfq_data *bfqd;

		struct request *prev, *next_rq;
@@ -2559,8 +2557,8 @@ static void bfq_request_merged(struct request_queue *q, struct request *req, 
static void bfq_requests_merged(struct request_queue *q, struct request *rq,

				struct request *next)

{

	struct bfq_queue *bfqq = bfq_init_rq(rq),

		*next_bfqq = bfq_init_rq(next);

	struct bfq_queue *bfqq = RQ_BFQQ(rq),

		*next_bfqq = RQ_BFQQ(next);



	if (!bfqq)

		goto remove;
@@ -6129,6 +6127,8 @@ static inline void bfq_update_insert_stats(struct request_queue *q, 
					   unsigned int cmd_flags) {}

#endif /* CONFIG_BFQ_CGROUP_DEBUG */



static struct bfq_queue *bfq_init_rq(struct request *rq);



static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,

			       bool at_head)

{
@@ -6144,6 +6144,7 @@ static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, 
		bfqg_stats_update_legacy_io(q, rq);

#endif

	spin_lock_irq(&bfqd->lock);

	bfqq = bfq_init_rq(rq);

	if (blk_mq_sched_try_insert_merge(q, rq, &free)) {

		spin_unlock_irq(&bfqd->lock);

		blk_mq_free_requests(&free);
@@ -6152,7 +6153,6 @@ static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, 


	trace_block_rq_insert(rq);



	bfqq = bfq_init_rq(rq);

	if (!bfqq || at_head) {

		if (at_head)

			list_add(&rq->queuelist, &bfqd->dispatch);