block: don't plug for aio/O_DIRECT HIPRI IO

Those will go straight to issue inside blk-mq, so don't bother
setting up a block plug for them.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2018-11-15 19:56:53 -07:00
parent d34513d384
commit cb700eb3fa

View File

@ -330,6 +330,7 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
struct blk_plug plug;
struct blkdev_dio *dio;
struct bio *bio;
bool is_poll = (iocb->ki_flags & IOCB_HIPRI) != 0;
bool is_read = (iov_iter_rw(iter) == READ), is_sync;
loff_t pos = iocb->ki_pos;
blk_qc_t qc = BLK_QC_T_NONE;
@ -353,7 +354,13 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
dio->multi_bio = false;
dio->should_dirty = is_read && iter_is_iovec(iter);
blk_start_plug(&plug);
/*
* Don't plug for HIPRI/polled IO, as those should go straight
* to issue
*/
if (!is_poll)
blk_start_plug(&plug);
for (;;) {
bio_set_dev(bio, bdev);
bio->bi_iter.bi_sector = pos >> 9;
@ -400,7 +407,9 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
submit_bio(bio);
bio = bio_alloc(GFP_KERNEL, nr_pages);
}
blk_finish_plug(&plug);
if (!is_poll)
blk_finish_plug(&plug);
if (!is_sync)
return -EIOCBQUEUED;