# \[PATCH 5/7\] direct-io: only use block polling if explicitly requested

- From: Christoph Hellwig \<hch@lst.de\>
- Date: 2016-02-22 17:08:04 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2016/02/105083
- Thread: https://ratatoskr.run/linux-fsdevel/2016/02/104289/t.md

```text
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/direct-io.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/direct-io.c b/fs/direct-io.c
index d6a9012..0a8d937 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -445,7 +445,8 @@ static struct bio *dio_await_one(struct dio *dio)
 		__set_current_state(TASK_UNINTERRUPTIBLE);
 		dio->waiter = current;
 		spin_unlock_irqrestore(&dio->bio_lock, flags);
-		if (!blk_poll(bdev_get_queue(dio->bio_bdev), dio->bio_cookie))
+		if (!(dio->iocb->ki_flags & IOCB_HIPRI) ||
+		    !blk_poll(bdev_get_queue(dio->bio_bdev), dio->bio_cookie))
 			io_schedule();
 		/* wake up sets us TASK_RUNNING */
 		spin_lock_irqsave(&dio->bio_lock, flags);
-- 
2.1.4

```