We will register debugfs for scheduler no matter whether it have defined callback funciton .exit_sched. So, blk_mq_exit_sched() is always needed to unregister debugfs. Also, q->elevator should be set as NULL after exiting scheduler. For now, since all register scheduler have defined .exit_sched, it will not cause any actual problem. But It will be more reasonable to do this change. Signed-off-by: Yufen Yu <yuyufen@xxxxxxxxxx> --- block/blk-sysfs.c | 1 - block/elevator.c | 3 +-- 2 files changed, 1 insertion(+), 3 deletions(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 7dda709f3ccb..ee2cd4d1054c 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -883,7 +883,6 @@ static void blk_exit_queue(struct request_queue *q) if (q->elevator) { ioc_clear_queue(q); __elevator_exit(q, q->elevator); - q->elevator = NULL; } /* diff --git a/block/elevator.c b/block/elevator.c index 6e775bd4af66..b506895b34c7 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -191,8 +191,7 @@ static void elevator_release(struct kobject *kobj) void __elevator_exit(struct request_queue *q, struct elevator_queue *e) { mutex_lock(&e->sysfs_lock); - if (e->type->ops.exit_sched) - blk_mq_exit_sched(q, e); + blk_mq_exit_sched(q, e); mutex_unlock(&e->sysfs_lock); kobject_put(&e->kobj); -- 2.25.4