From 6a3c8a3ac0e68dcfc2a01f4aa1ca0edd1a1701eb Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Sat, 19 Apr 2014 18:00:19 +0800 Subject: [PATCH] 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: Ming Lei Signed-off-by: Jens Axboe --- block/blk-mq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 3a560a4db0b4..c26b3be1893c 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -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,