Commit 6a3c8a3a authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

blk-mq: initialize req->q in allocation 



The patch basically reverts the patch of(blk-mq:
initialize request on allocation) in Jens's tree(already
in -next), and only initialize req->q in allocation
for two reasons:

	- presumed cache hotness on completion
	- blk_rq_tagged(rq) depends on reset of req->mq_ctx

Signed-off-by: default avatarMing Lei <tom.leiming@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent 4ca08500

block/blk-mq.c

+3 −1
Original line number Diff line number Diff line
@@ -82,7 +82,6 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_hw_ctx *hctx, 
	tag = blk_mq_get_tag(hctx->tags, gfp, reserved);

	if (tag != BLK_MQ_TAG_FAIL) {

		rq = hctx->tags->rqs[tag];

		blk_rq_init(hctx->queue, rq);

		rq->tag = tag;



		return rq;
@@ -187,6 +186,7 @@ static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, 
	if (blk_queue_io_stat(q))

		rw_flags |= REQ_IO_STAT;



	rq->q = q;

	rq->mq_ctx = ctx;

	rq->cmd_flags = rw_flags;

	rq->start_time = jiffies;
@@ -258,6 +258,7 @@ static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, 
	const int tag = rq->tag;

	struct request_queue *q = rq->q;



	blk_rq_init(hctx->queue, rq);

	blk_mq_put_tag(hctx->tags, tag);

	blk_mq_queue_exit(q);

}
@@ -1194,6 +1195,7 @@ static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, 
		left -= to_do * rq_size;

		for (j = 0; j < to_do; j++) {

			tags->rqs[i] = p;

			blk_rq_init(NULL, tags->rqs[i]);

			if (set->ops->init_request) {

				if (set->ops->init_request(set->driver_data,

						tags->rqs[i], hctx_idx, i,

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