From f6f371f7db42917c7b2a861c4fc923cb352ce5a1 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Sun, 6 Dec 2020 14:04:39 +0000 Subject: 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 Signed-off-by: Jens Axboe --- block/blk-mq.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index cf3916e2852f..2881a457de83 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -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++; -- cgit v1.2.3