blk-mq: clarify dispatch may not be drained/blocked by stopping queue
authorMing Lei <ming.lei@redhat.com>
Tue, 6 Jun 2017 15:22:09 +0000 (23:22 +0800)
committerJens Axboe <axboe@kernel.dk>
Sun, 18 Jun 2017 20:24:48 +0000 (14:24 -0600)
commit39a70c76b89b81db91a72a86b6c6a9b239013417
tree8fa5baf83a330c9e38df72270484d6e41e5a1fa6
parent1d9e9bc6b56e1bb7e33e7e2e1b99d7088356c006
blk-mq: clarify dispatch may not be drained/blocked by stopping queue

BLK_MQ_S_STOPPED may not be observed in other concurrent I/O paths,
we can't guarantee that dispatching won't happen after returning
from the APIs of stopping queue.

So clarify the fact and avoid potential misuse.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/blk-mq.c