diff options
-rw-r--r-- | block/blk-mq.c | 50 |
1 files changed, 43 insertions, 7 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index a5e66a7a3506..e797607dab89 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -876,12 +876,9 @@ done: return false; } -static void blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, - struct request *rq) +static void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, + struct request *rq) { - if (rq->tag == -1 || rq->internal_tag == -1) - return; - blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag); rq->tag = -1; @@ -891,6 +888,26 @@ static void blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, } } +static void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx, + struct request *rq) +{ + if (rq->tag == -1 || rq->internal_tag == -1) + return; + + __blk_mq_put_driver_tag(hctx, rq); +} + +static void blk_mq_put_driver_tag(struct request *rq) +{ + struct blk_mq_hw_ctx *hctx; + + if (rq->tag == -1 || rq->internal_tag == -1) + return; + + hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu); + __blk_mq_put_driver_tag(hctx, rq); +} + /* * If we fail getting a driver tag because all the driver tags are already * assigned and on the dispatch list, BUT the first entry does not have a @@ -1000,7 +1017,19 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list) bd.rq = rq; bd.list = dptr; - bd.last = list_empty(list); + + /* + * Flag last if we have no more requests, or if we have more + * but can't assign a driver tag to it. + */ + if (list_empty(list)) + bd.last = true; + else { + struct request *nxt; + + nxt = list_first_entry(list, struct request, queuelist); + bd.last = !blk_mq_get_driver_tag(nxt, NULL, false); + } ret = q->mq_ops->queue_rq(hctx, &bd); switch (ret) { @@ -1008,7 +1037,7 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list) queued++; break; case BLK_MQ_RQ_QUEUE_BUSY: - blk_mq_put_driver_tag(hctx, rq); + blk_mq_put_driver_tag_hctx(hctx, rq); list_add(&rq->queuelist, list); __blk_mq_requeue_request(rq); break; @@ -1038,6 +1067,13 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list) * that is where we will continue on next queue run. */ if (!list_empty(list)) { + /* + * If we got a driver tag for the next request already, + * free it again. + */ + rq = list_first_entry(list, struct request, queuelist); + blk_mq_put_driver_tag(rq); + spin_lock(&hctx->lock); list_splice_init(list, &hctx->dispatch); spin_unlock(&hctx->lock); |