[PATCH 1/4] io_uring: remove setting REQ_F_MUST_PUNT in rw

From: Pavel Begunkov
Date: Sun Jun 21 2020 - 06:11:46 EST


io_{read,write}() {
...
copy_iov: // prep async
if (!(flags & REQ_F_NOWAIT) && !file_can_poll(file))
flags |= REQ_F_MUST_PUNT;
}

REQ_F_MUST_PUNT there is pointless, because if it happens then
REQ_F_NOWAIT is known to be _not_ set, and the request will go
async path in __io_queue_sqe() anyway. file_can_poll() check
is also repeated in arm_poll*(), so don't need it.

Remove the mentioned assignment REQ_F_MUST_PUNT in preparation
for killing the flag.

Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
fs/io_uring.c | 8 --------
1 file changed, 8 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 44614571e285..e7ce1608087f 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2915,10 +2915,6 @@ static int io_read(struct io_kiocb *req, bool force_nonblock)
inline_vecs, &iter);
if (ret)
goto out;
- /* any defer here is final, must blocking retry */
- if (!(req->flags & REQ_F_NOWAIT) &&
- !file_can_poll(req->file))
- req->flags |= REQ_F_MUST_PUNT;
/* if we can retry, do so with the callbacks armed */
if (io_rw_should_retry(req)) {
ret2 = io_iter_do_read(req, &iter);
@@ -3050,10 +3046,6 @@ static int io_write(struct io_kiocb *req, bool force_nonblock)
inline_vecs, &iter);
if (ret)
goto out_free;
- /* any defer here is final, must blocking retry */
- if (!(req->flags & REQ_F_NOWAIT) &&
- !file_can_poll(req->file))
- req->flags |= REQ_F_MUST_PUNT;
return -EAGAIN;
}
}
--
2.24.0