This patch makes it safe to access the queue usage counter from inside blk_mq_run_hw_queues(). Other than deferring q_usage_counter freeing, this patch does not change any functionality. Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Hannes Reinecke <hare@xxxxxxxx> Cc: James Smart <james.smart@xxxxxxxxxxxx> Cc: Ming Lei <ming.lei@xxxxxxxxxx> Cc: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx> Cc: Dongli Zhang <dongli.zhang@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx> --- block/blk-core.c | 2 -- block/blk-sysfs.c | 1 + 2 files changed, 1 insertion(+), 2 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 4673ebe42255..fdcf6de2243f 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -377,8 +377,6 @@ void blk_cleanup_queue(struct request_queue *q) if (queue_is_mq(q)) blk_mq_free_queue(q); - percpu_ref_exit(&q->q_usage_counter); - /* @q is and will stay empty, shutdown and put */ blk_put_queue(q); } diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 422327089e0f..b8b3d69cd0a5 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -870,6 +870,7 @@ static void __blk_release_queue(struct work_struct *work) bioset_exit(&q->bio_split); + percpu_ref_exit(&q->q_usage_counter); ida_simple_remove(&blk_queue_ida, q->id); call_rcu(&q->rcu_head, blk_free_queue_rcu); } -- 2.21.0.196.g041f5ea1cf98