Commit 89ea5ceb authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

blk-mq: cleanup __blk_mq_sched_dispatch_requests 



__blk_mq_sched_dispatch_requests currently has duplicated logic
for the cases where requests are on the hctx dispatch list or not.
Merge the two with a new need_dispatch variable and remove a few
pointless local variables.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20230413060651.694656-2-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent b12e5c6c

block/blk-mq-sched.c

+14 −17
Original line number Diff line number Diff line
@@ -269,9 +269,7 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) 


static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx)

{

	struct request_queue *q = hctx->queue;

	const bool has_sched = q->elevator;

	int ret = 0;

	bool need_dispatch = false;

	LIST_HEAD(rq_list);



	/*
@@ -300,23 +298,22 @@ static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) 
	 */

	if (!list_empty(&rq_list)) {

		blk_mq_sched_mark_restart_hctx(hctx);

		if (blk_mq_dispatch_rq_list(hctx, &rq_list, 0)) {

			if (has_sched)

				ret = blk_mq_do_dispatch_sched(hctx);

			else

				ret = blk_mq_do_dispatch_ctx(hctx);

		if (!blk_mq_dispatch_rq_list(hctx, &rq_list, 0))

			return 0;

		need_dispatch = true;

	} else {

		need_dispatch = hctx->dispatch_busy;

	}

	} else if (has_sched) {

		ret = blk_mq_do_dispatch_sched(hctx);

	} else if (hctx->dispatch_busy) {



	if (hctx->queue->elevator)

		return blk_mq_do_dispatch_sched(hctx);



	/* dequeue request one by one from sw queue if queue is busy */

		ret = blk_mq_do_dispatch_ctx(hctx);

	} else {

	if (need_dispatch)

		return blk_mq_do_dispatch_ctx(hctx);

	blk_mq_flush_busy_ctxs(hctx, &rq_list);

	blk_mq_dispatch_rq_list(hctx, &rq_list, 0);

	}



	return ret;

	return 0;

}



void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx)