In the following patch, we will use blk_mq_try_issue_directly() for DM to return the dispatch result, and DM need this informatin to improve IO merge.
Signed-off-by: Ming Lei <[email protected]> --- block/blk-mq.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index fe82d7a47b35..fd4fb6316ea1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1620,13 +1620,14 @@ static bool __blk_mq_issue_req(struct blk_mq_hw_ctx *hctx, return false; } -static void __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, - struct request *rq, - blk_qc_t *cookie, bool may_sleep) +static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, + struct request *rq, + blk_qc_t *cookie, + bool may_sleep) { struct request_queue *q = rq->q; blk_qc_t new_cookie; - blk_status_t ret; + blk_status_t ret = BLK_STS_OK; bool run_queue = true; /* RCU or SRCU read lock is needed before checking quiesced flag */ @@ -1649,26 +1650,30 @@ static void __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, switch (ret) { case BLK_STS_OK: *cookie = new_cookie; - return; + return ret; case BLK_STS_RESOURCE: __blk_mq_requeue_request(rq); goto insert; default: *cookie = BLK_QC_T_NONE; blk_mq_end_request(rq, ret); - return; + return ret; } insert: blk_mq_sched_insert_request(rq, false, run_queue, false, may_sleep); + return ret; } -static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, - struct request *rq, blk_qc_t *cookie) +static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, + struct request *rq, + blk_qc_t *cookie) { + blk_status_t ret; + if (!(hctx->flags & BLK_MQ_F_BLOCKING)) { rcu_read_lock(); - __blk_mq_try_issue_directly(hctx, rq, cookie, false); + ret = __blk_mq_try_issue_directly(hctx, rq, cookie, false); rcu_read_unlock(); } else { unsigned int srcu_idx; @@ -1676,9 +1681,11 @@ static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, might_sleep(); srcu_idx = srcu_read_lock(hctx->queue_rq_srcu); - __blk_mq_try_issue_directly(hctx, rq, cookie, true); + ret = __blk_mq_try_issue_directly(hctx, rq, cookie, true); srcu_read_unlock(hctx->queue_rq_srcu, srcu_idx); } + + return ret; } static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) -- 2.9.5
