Commit 7f2799c5 authored by Yu Kuai's avatar Yu Kuai Committed by Jens Axboe
Browse files

blk-mq: cleanup shared tags case in blk_mq_update_nr_requests() 



For shared tags case, all hctx->sched_tags/tags are the same, it doesn't
make sense to call into blk_mq_tag_update_depth() multiple times for the
same tags.

Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Reviewed-by: default avatarNilay Shroff <nilay@linux.ibm.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 626ff4f8

block/blk-mq-tag.c

+0 −7
Original line number Diff line number Diff line
@@ -622,13 +622,6 @@ int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, 
		struct blk_mq_tag_set *set = hctx->queue->tag_set;

		struct blk_mq_tags *new;



		/*

		 * Only the sbitmap needs resizing since we allocated the max

		 * initially.

		 */

		if (blk_mq_is_shared_tags(set->flags))

			return 0;



		new = blk_mq_alloc_map_and_rqs(set, hctx->queue_num, tdepth);

		if (!new)

			return -ENOMEM;

block/blk-mq.c

+22 −21
Original line number Diff line number Diff line
@@ -4935,34 +4935,35 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) 


	blk_mq_quiesce_queue(q);



	if (blk_mq_is_shared_tags(set->flags)) {

		if (q->elevator)

			blk_mq_tag_update_sched_shared_tags(q);

		else

			blk_mq_tag_resize_shared_tags(set, nr);

	} else {

		queue_for_each_hw_ctx(q, hctx, i) {

			if (!hctx->tags)

				continue;

			/*

		 * If we're using an MQ scheduler, just update the scheduler

		 * queue depth. This is similar to what the old code would do.

			 * If we're using an MQ scheduler, just update the

			 * scheduler queue depth. This is similar to what the

			 * old code would do.

			 */

		if (hctx->sched_tags) {

			ret = blk_mq_tag_update_depth(hctx, &hctx->sched_tags,

						      nr);

		} else {

			ret = blk_mq_tag_update_depth(hctx, &hctx->tags, nr);

		}

			if (hctx->sched_tags)

				ret = blk_mq_tag_update_depth(hctx,

							&hctx->sched_tags, nr);

			else

				ret = blk_mq_tag_update_depth(hctx,

							&hctx->tags, nr);

			if (ret)

				goto out;

		}

	}



	q->nr_requests = nr;

	if (q->elevator && q->elevator->type->ops.depth_updated)

		q->elevator->type->ops.depth_updated(q);



	if (blk_mq_is_shared_tags(set->flags)) {

		if (q->elevator)

			blk_mq_tag_update_sched_shared_tags(q);

		else

			blk_mq_tag_resize_shared_tags(set, nr);

	}



out:

	blk_mq_unquiesce_queue(q);