diff options
| author | Ming Lei <ming.lei@redhat.com> | 2021-11-02 16:36:19 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-11-03 16:27:57 +0100 |
| commit | 3b87c6ea671a18fb77709240d658f4201904f8e4 (patch) | |
| tree | b00741334fd7d7a7e1fed3350bd6a2172db76ab2 /block | |
| parent | blk-mq: add RQF_ELV debug entry (diff) | |
| download | linux-3b87c6ea671a18fb77709240d658f4201904f8e4.tar.xz linux-3b87c6ea671a18fb77709240d658f4201904f8e4.zip | |
blk-mq: update hctx->nr_active in blk_mq_end_request_batch()
In case of shared tags and none io sched, batched completion still may
be run into, and hctx->nr_active is accounted when getting driver tag,
so it has to be updated in blk_mq_end_request_batch().
Otherwise, hctx->nr_active may become same with queue depth, then
hctx_may_queue() always return false, then io hang is caused.
Fixes the issue by updating the counter in batched way.
Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Fixes: f794f3351f26 ("block: add support for blk_mq_end_request_batch()")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211102153619.3627505-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-mq.c | 7 | ||||
| -rw-r--r-- | block/blk-mq.h | 12 |
2 files changed, 16 insertions, 3 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 00263d896843..c68aa0a332e1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -818,6 +818,13 @@ static inline void blk_mq_flush_tag_batch(struct blk_mq_hw_ctx *hctx, { struct request_queue *q = hctx->queue; + /* + * All requests should have been marked as RQF_MQ_INFLIGHT, so + * update hctx->nr_active in batch + */ + if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) + __blk_mq_sub_active_requests(hctx, nr_tags); + blk_mq_put_tags(hctx->tags, tag_array, nr_tags); percpu_ref_put_many(&q->q_usage_counter, nr_tags); } diff --git a/block/blk-mq.h b/block/blk-mq.h index 28859fc5faee..cb0b5482ca5e 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -225,12 +225,18 @@ static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx) atomic_inc(&hctx->nr_active); } -static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx) +static inline void __blk_mq_sub_active_requests(struct blk_mq_hw_ctx *hctx, + int val) { if (blk_mq_is_shared_tags(hctx->flags)) - atomic_dec(&hctx->queue->nr_active_requests_shared_tags); + atomic_sub(val, &hctx->queue->nr_active_requests_shared_tags); else - atomic_dec(&hctx->nr_active); + atomic_sub(val, &hctx->nr_active); +} + +static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx) +{ + __blk_mq_sub_active_requests(hctx, 1); } static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx) |