[PATCH V6 1/6] blk-mq: pass request queue into get/put budget callback
From: Ming Lei <hidden>
Date: 2020-06-24 23:04:15
Subsystem:
block layer, scsi subsystem, the rest · Maintainers:
Jens Axboe, "James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds
blk-mq budget is abstract from scsi's device queue depth, and it is always per-request-queue instead of hctx. It can be quite absurd to get a budget from one hctx, then dequeue a request from scheduler queue, and this request may not belong to this hctx, at least for bfq and deadline. So fix the mess and always pass request queue to get/put budget callback. Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Baolin Wang <baolin.wang7@gmail.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Douglas Anderson <dianders@chromium.org> Reviewed-by: Johannes Thumshirn <redacted> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Tested-by: Baolin Wang <baolin.wang7@gmail.com> Signed-off-by: Ming Lei <redacted> --- block/blk-mq-sched.c | 8 ++++---- block/blk-mq.c | 8 ++++---- block/blk-mq.h | 12 ++++-------- drivers/scsi/scsi_lib.c | 8 +++----- include/linux/blk-mq.h | 4 ++-- 5 files changed, 17 insertions(+), 23 deletions(-)
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index fdcc2c1dd178..a31e281e9d31 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c@@ -108,12 +108,12 @@ static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) break; } - if (!blk_mq_get_dispatch_budget(hctx)) + if (!blk_mq_get_dispatch_budget(q)) break; rq = e->type->ops.dispatch_request(hctx); if (!rq) { - blk_mq_put_dispatch_budget(hctx); + blk_mq_put_dispatch_budget(q); /* * We're releasing without dispatching. Holding the * budget could have blocked any "hctx"s with the
@@ -173,12 +173,12 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) if (!sbitmap_any_bit_set(&hctx->ctx_map)) break; - if (!blk_mq_get_dispatch_budget(hctx)) + if (!blk_mq_get_dispatch_budget(q)) break; rq = blk_mq_dequeue_from_ctx(hctx, ctx); if (!rq) { - blk_mq_put_dispatch_budget(hctx); + blk_mq_put_dispatch_budget(q); /* * We're releasing without dispatching. Holding the * budget could have blocked any "hctx"s with the
diff --git a/block/blk-mq.c b/block/blk-mq.c
index b8738b3c6d06..9eea9c19bca2 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c@@ -1286,7 +1286,7 @@ 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; - if (!got_budget && !blk_mq_get_dispatch_budget(hctx)) { + if (!got_budget && !blk_mq_get_dispatch_budget(q)) { blk_mq_put_driver_tag(rq); no_budget_avail = true; break;
@@ -1301,7 +1301,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, * we'll re-run it below. */ if (!blk_mq_mark_tag_wait(hctx, rq)) { - blk_mq_put_dispatch_budget(hctx); + blk_mq_put_dispatch_budget(q); /* * For non-shared tags, the RESTART check * will suffice.
@@ -1949,11 +1949,11 @@ static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, if (q->elevator && !bypass_insert) goto insert; - if (!blk_mq_get_dispatch_budget(hctx)) + if (!blk_mq_get_dispatch_budget(q)) goto insert; if (!blk_mq_get_driver_tag(rq)) { - blk_mq_put_dispatch_budget(hctx); + blk_mq_put_dispatch_budget(q); goto insert; }
diff --git a/block/blk-mq.h b/block/blk-mq.h
index b3ce0f3a2ad2..4408f09d7bff 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h@@ -179,20 +179,16 @@ unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part); void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part, unsigned int inflight[2]); -static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx) +static inline void blk_mq_put_dispatch_budget(struct request_queue *q) { - struct request_queue *q = hctx->queue; - if (q->mq_ops->put_budget) - q->mq_ops->put_budget(hctx); + q->mq_ops->put_budget(q); } -static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx) +static inline bool blk_mq_get_dispatch_budget(struct request_queue *q) { - struct request_queue *q = hctx->queue; - if (q->mq_ops->get_budget) - return q->mq_ops->get_budget(hctx); + return q->mq_ops->get_budget(q); return true; }
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 6ca91d09eca1..534b85e87c80 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c@@ -1597,17 +1597,15 @@ static void scsi_mq_done(struct scsi_cmnd *cmd) blk_mq_complete_request(cmd->request); } -static void scsi_mq_put_budget(struct blk_mq_hw_ctx *hctx) +static void scsi_mq_put_budget(struct request_queue *q) { - struct request_queue *q = hctx->queue; struct scsi_device *sdev = q->queuedata; atomic_dec(&sdev->device_busy); } -static bool scsi_mq_get_budget(struct blk_mq_hw_ctx *hctx) +static bool scsi_mq_get_budget(struct request_queue *q) { - struct request_queue *q = hctx->queue; struct scsi_device *sdev = q->queuedata; return scsi_dev_queue_ready(q, sdev);
@@ -1674,7 +1672,7 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, if (scsi_target(sdev)->can_queue > 0) atomic_dec(&scsi_target(sdev)->target_busy); out_put_budget: - scsi_mq_put_budget(hctx); + scsi_mq_put_budget(q); switch (ret) { case BLK_STS_OK: break;
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 1641ec6cd7e5..e19efe43b57e 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h@@ -270,8 +270,8 @@ struct blk_mq_queue_data { typedef blk_status_t (queue_rq_fn)(struct blk_mq_hw_ctx *, const struct blk_mq_queue_data *); typedef void (commit_rqs_fn)(struct blk_mq_hw_ctx *); -typedef bool (get_budget_fn)(struct blk_mq_hw_ctx *); -typedef void (put_budget_fn)(struct blk_mq_hw_ctx *); +typedef bool (get_budget_fn)(struct request_queue *); +typedef void (put_budget_fn)(struct request_queue *); typedef enum blk_eh_timer_return (timeout_fn)(struct request *, bool); typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int); typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
--
2.25.2