blk-mq: skip hybrid polling if iopoll doesn't spin

If blk_poll() is not going to spin (i.e. @spin=false), it also must not
sleep in hybrid polling, otherwise it might be pretty suprising for
users trying to do a quick check and expecting no-wait behaviour.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2020-12-06 14:04:39 +00:00 committed by Jens Axboe
parent 926f75f6a9
commit f6f371f7db

View file

@ -3865,9 +3865,10 @@ int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin)
* the state. Like for the other success return cases, the
* caller is responsible for checking if the IO completed. If
* the IO isn't complete, we'll get called again and will go
* straight to the busy poll loop.
* straight to the busy poll loop. If specified not to spin,
* we also should not sleep.
*/
if (blk_mq_poll_hybrid(q, hctx, cookie))
if (spin && blk_mq_poll_hybrid(q, hctx, cookie))
return 1;
hctx->poll_considered++;