[PATCH v2 1/4] block/mq-deadline: Improve request accounting further
From: Bart Van Assche <bvanassche@acm.org>
Date: 2021-09-27 22:03:54
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
The scheduler .insert_requests() callback is called when a request is
queued for the first time and also when it is requeued. Only count a
request the first time it is queued. Additionally, since the mq-deadline
scheduler only performs zone locking for requests that have been
inserted, skip the zone unlock code for requests that have not been
inserted into the mq-deadline scheduler.
Fixes: 38ba64d12d4c ("block/mq-deadline: Track I/O statistics")
Reviewed-by: Damien Le Moal <redacted>
Reviewed-by: Niklas Cassel <redacted>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
block/mq-deadline.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/block/mq-deadline.c b/block/mq-deadline.c
index 47f042fa6a68..c27b4347ca91 100644
--- a/block/mq-deadline.c
+++ b/block/mq-deadline.c@@ -677,8 +677,10 @@ static void dd_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, blk_req_zone_write_unlock(rq); prio = ioprio_class_to_prio[ioprio_class]; - dd_count(dd, inserted, prio); - rq->elv.priv[0] = (void *)(uintptr_t)1; + if (!rq->elv.priv[0]) { + dd_count(dd, inserted, prio); + rq->elv.priv[0] = (void *)(uintptr_t)1; + } if (blk_mq_sched_try_insert_merge(q, rq, &free)) { blk_mq_free_requests(&free);
@@ -759,12 +761,13 @@ static void dd_finish_request(struct request *rq) /* * The block layer core may call dd_finish_request() without having - * called dd_insert_requests(). Hence only update statistics for - * requests for which dd_insert_requests() has been called. See also - * blk_mq_request_bypass_insert(). + * called dd_insert_requests(). Skip requests that bypassed I/O + * scheduling. See also blk_mq_request_bypass_insert(). */ - if (rq->elv.priv[0]) - dd_count(dd, completed, prio); + if (!rq->elv.priv[0]) + return; + + dd_count(dd, completed, prio); if (blk_queue_is_zoned(q)) { unsigned long flags;