io_uring: reshuffle queue_sqe completion handling
authorPavel Begunkov <asml.silence@gmail.com>
Fri, 24 Sep 2021 21:00:00 +0000 (22:00 +0100)
committerJens Axboe <axboe@kernel.dk>
Tue, 19 Oct 2021 11:49:54 +0000 (05:49 -0600)
If a request completed inline the result should only be zero, it's a
grave error otherwise. So, when we see REQ_F_COMPLETE_INLINE it's not
even necessary to check the return code, and the flag check can be moved
earlier.

It's one "if" less for inline completions, and same two checks for it
normally completing (ret == 0). Those are two cases we care about the
most.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ebd4e397a9c26d96c99b24447acc309741041a83.1632516769.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
fs/io_uring.c

index d4f8abb..bbb2a26 100644 (file)
@@ -6925,14 +6925,13 @@ static inline void __io_queue_sqe(struct io_kiocb *req)
 
        ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
 
+       if (req->flags & REQ_F_COMPLETE_INLINE)
+               return;
        /*
         * We async punt it if the file wasn't marked NOWAIT, or if the file
         * doesn't support non-blocking read/write attempts
         */
        if (likely(!ret)) {
-               if (req->flags & REQ_F_COMPLETE_INLINE)
-                       return;
-
                linked_timeout = io_prep_linked_timeout(req);
                if (linked_timeout)
                        io_queue_linked_timeout(linked_timeout);