From 445874e89f662c8c6a56e6bb820cbe9fbef61428 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Tue, 30 Jun 2020 18:24:57 +0800 Subject: [PATCH] blk-mq: pass hctx to blk_mq_dispatch_rq_list All requests in the 'list' of blk_mq_dispatch_rq_list belong to same hctx, so it is better to pass hctx instead of request queue, because blk-mq's dispatch target is hctx instead of request queue. Signed-off-by: Ming Lei Tested-by: Baolin Wang Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Reviewed-by: Johannes Thumshirn Cc: Sagi Grimberg Cc: Baolin Wang Cc: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq-sched.c | 14 ++++++-------- block/blk-mq.c | 6 +++--- block/blk-mq.h | 2 +- 3 files changed, 10 insertions(+), 12 deletions(-) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index a31e281..632c6f8 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -96,10 +96,9 @@ static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) struct elevator_queue *e = q->elevator; LIST_HEAD(rq_list); int ret = 0; + struct request *rq; do { - struct request *rq; - if (e->type->ops.has_work && !e->type->ops.has_work(hctx)) break; @@ -131,7 +130,7 @@ static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) * in blk_mq_dispatch_rq_list(). */ list_add(&rq->queuelist, &rq_list); - } while (blk_mq_dispatch_rq_list(q, &rq_list, true)); + } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, true)); return ret; } @@ -161,10 +160,9 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) LIST_HEAD(rq_list); struct blk_mq_ctx *ctx = READ_ONCE(hctx->dispatch_from); int ret = 0; + struct request *rq; do { - struct request *rq; - if (!list_empty_careful(&hctx->dispatch)) { ret = -EAGAIN; break; @@ -200,7 +198,7 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) /* round robin for fair dispatch */ ctx = blk_mq_next_ctx(hctx, rq->mq_ctx); - } while (blk_mq_dispatch_rq_list(q, &rq_list, true)); + } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, true)); WRITE_ONCE(hctx->dispatch_from, ctx); return ret; @@ -240,7 +238,7 @@ static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) */ if (!list_empty(&rq_list)) { blk_mq_sched_mark_restart_hctx(hctx); - if (blk_mq_dispatch_rq_list(q, &rq_list, false)) { + if (blk_mq_dispatch_rq_list(hctx, &rq_list, false)) { if (has_sched_dispatch) ret = blk_mq_do_dispatch_sched(hctx); else @@ -253,7 +251,7 @@ static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) ret = blk_mq_do_dispatch_ctx(hctx); } else { blk_mq_flush_busy_ctxs(hctx, &rq_list); - blk_mq_dispatch_rq_list(q, &rq_list, false); + blk_mq_dispatch_rq_list(hctx, &rq_list, false); } return ret; diff --git a/block/blk-mq.c b/block/blk-mq.c index 8cdc868..492aeda 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1258,10 +1258,10 @@ static void blk_mq_handle_zone_resource(struct request *rq, /* * Returns true if we did some work AND can potentially do more. */ -bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, +bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list, bool got_budget) { - struct blk_mq_hw_ctx *hctx; + struct request_queue *q = hctx->queue; struct request *rq, *nxt; bool no_tag = false; int errors, queued; @@ -1283,7 +1283,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, rq = list_first_entry(list, struct request, queuelist); - hctx = rq->mq_hctx; + WARN_ON_ONCE(hctx != rq->mq_hctx); if (!got_budget && !blk_mq_get_dispatch_budget(q)) { blk_mq_put_driver_tag(rq); no_budget_avail = true; diff --git a/block/blk-mq.h b/block/blk-mq.h index e4af193..3fd1ed7 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -40,7 +40,7 @@ struct blk_mq_ctx { void blk_mq_exit_queue(struct request_queue *q); int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr); void blk_mq_wake_waiters(struct request_queue *q); -bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool); +bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *, bool); void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, bool kick_requeue_list); void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list); -- 2.7.4