io_uring's direct nowait requests end up waiting on io_schedule() in sbitmap, that's seems to be so because blkdev_direct_IO() fails to propagate IOCB_NOWAIT to a bio and hence to blk-mq.
Signed-off-by: Pavel Begunkov <[email protected]> --- fs/block_dev.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/block_dev.c b/fs/block_dev.c index 9e84b1928b94..e7e860c78d93 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -263,6 +263,8 @@ __blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter, bio.bi_opf = dio_bio_write_op(iocb); task_io_account_write(ret); } + if (iocb->ki_flags & IOCB_NOWAIT) + bio.bi_opf |= REQ_NOWAIT; if (iocb->ki_flags & IOCB_HIPRI) bio_set_polled(&bio, iocb); @@ -416,6 +418,8 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages) bio->bi_opf = dio_bio_write_op(iocb); task_io_account_write(bio->bi_iter.bi_size); } + if (iocb->ki_flags & IOCB_NOWAIT) + bio->bi_opf |= REQ_NOWAIT; dio->size += bio->bi_iter.bi_size; pos += bio->bi_iter.bi_size; -- 2.24.0
