diff options
| author | Jens Axboe <axboe@kernel.dk> | 2023-01-21 10:39:22 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-24 07:19:57 +0100 |
| commit | 4bc17e6381bdbe7373ffccbda94db56631061a4a (patch) | |
| tree | 01d7ea725578eb16685e2b427824506e522fa4e2 /io_uring | |
| parent | f901b4bfd03ed234f72f28e27d965569531dc505 (diff) | |
io_uring: allow re-poll if we made progress
commit 10c873334febaeea9aa0c25c10b5ac0951b77a5f upstream.
We currently check REQ_F_POLLED before arming async poll for a
notification to retry. If it's set, then we don't allow poll and will
punt to io-wq instead. This is done to prevent a situation where a buggy
driver will repeatedly return that there's space/data available yet we
get -EAGAIN.
However, if we already transferred data, then it should be safe to rely
on poll again. Gate the check on whether or not REQ_F_PARTIAL_IO is
also set.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/io_uring.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 75d833269751..cc8e13de5fa9 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -5694,7 +5694,7 @@ static int io_arm_poll_handler(struct io_kiocb *req) if (!req->file || !file_can_poll(req->file)) return IO_APOLL_ABORTED; - if (req->flags & REQ_F_POLLED) + if ((req->flags & (REQ_F_POLLED|REQ_F_PARTIAL_IO)) == REQ_F_POLLED) return IO_APOLL_ABORTED; if (!def->pollin && !def->pollout) return IO_APOLL_ABORTED; @@ -5710,7 +5710,10 @@ static int io_arm_poll_handler(struct io_kiocb *req) mask |= POLLOUT | POLLWRNORM; } - apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC); + if (req->flags & REQ_F_POLLED) + apoll = req->apoll; + else + apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC); if (unlikely(!apoll)) return IO_APOLL_ABORTED; apoll->double_poll = NULL; |