From: Pavel Begunkov <asml.silence@gmail.com>
Date: Tue, 19 Jan 2021 13:32:34 +0000 (+0000)
Subject: io_uring: optimise io_rw_reissue()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bf6182b6d46e28c3e59b9c0d6097b379cae56b94;p=linux.git

io_uring: optimise io_rw_reissue()

The hot path is IO completing on the first try. Reshuffle io_rw_reissue() so
it's checked first.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 98789fece715a..4a8900d480c56 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2738,12 +2738,13 @@ end_req:
 static bool io_rw_reissue(struct io_kiocb *req, long res)
 {
 #ifdef CONFIG_BLOCK
-	umode_t mode = file_inode(req->file)->i_mode;
+	umode_t mode;
 	int ret;
 
-	if (!S_ISBLK(mode) && !S_ISREG(mode))
+	if (res != -EAGAIN && res != -EOPNOTSUPP)
 		return false;
-	if ((res != -EAGAIN && res != -EOPNOTSUPP) || io_wq_current_is_worker())
+	mode = file_inode(req->file)->i_mode;
+	if ((!S_ISBLK(mode) && !S_ISREG(mode)) || io_wq_current_is_worker())
 		return false;
 
 	lockdep_assert_held(&req->ctx->uring_lock);