Commit 3bee991f authored by Zhaoyang Huang's avatar Zhaoyang Huang Committed by Jens Axboe
Browse files

loop: release the lo_work_lock before queue_work 



queue_work could spin on wq->cpu_pwq->pool->lock which could lead to
concurrent loop_process_work failed on lo_work_lock contention and
increase the request latency. Remove this combination by moving the
lock release ahead of queue_work.

Signed-off-by: default avatarZhaoyang Huang <zhaoyang.huang@unisoc.com>
Link: https://lore.kernel.org/r/20250207091942.3966756-1-zhaoyang.huang@unisoc.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 1ebd4a3c

drivers/block/loop.c

+1 −1
Original line number Diff line number Diff line
@@ -894,8 +894,8 @@ static void loop_queue_work(struct loop_device *lo, struct loop_cmd *cmd) 
		cmd_list = &lo->rootcg_cmd_list;

	}

	list_add_tail(&cmd->list_entry, cmd_list);

	queue_work(lo->workqueue, work);

	spin_unlock_irq(&lo->lo_work_lock);

	queue_work(lo->workqueue, work);

}



static void loop_set_timer(struct loop_device *lo)