diff options
| author | Ming Lei | 2022-06-16 09:44:01 +0800 |
|---|---|---|
| committer | Jens Axboe | 2022-06-16 14:45:15 -0600 |
| commit | 6cfeadbff3f8905f2854735ebb88e581402c16c4 (patch) | |
| tree | edb82888efd3a884207c640f88837f5ab11fa0f3 | |
| parent | 4d337cebcb1c27d9b48c48b9a98e939d4552d584 (diff) | |
blk-mq: don't clear flush_rq from tags->rqs[]
commit 364b61818f65 ("blk-mq: clearing flush request reference in
tags->rqs[]") is added to clear the to-be-free flush request from
tags->rqs[] for avoiding use-after-free on the flush rq.
Yu Kuai reported that blk_mq_clear_flush_rq_mapping() slows down boot time
by ~8s because running scsi probe which may create and remove lots of
unpresent LUNs on megaraid-sas which uses BLK_MQ_F_TAG_HCTX_SHARED and
each request queue has lots of hw queues.
Improve the situation by not running blk_mq_clear_flush_rq_mapping if
disk isn't added when there can't be any flush request issued.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reported-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220616014401.817001-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/blk-mq.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 4cdb08a70912..33145ba52c96 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3431,8 +3431,9 @@ static void blk_mq_exit_hctx(struct request_queue *q, if (blk_mq_hw_queue_mapped(hctx)) blk_mq_tag_idle(hctx); - blk_mq_clear_flush_rq_mapping(set->tags[hctx_idx], - set->queue_depth, flush_rq); + if (blk_queue_init_done(q)) + blk_mq_clear_flush_rq_mapping(set->tags[hctx_idx], + set->queue_depth, flush_rq); if (set->ops->exit_request) set->ops->exit_request(set, flush_rq, hctx_idx); |