From 9983028e7660a2cc5e58403d8ce29569dbf3162d Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@gmail.com>
Date: Fri, 15 Oct 2021 17:09:11 +0100
Subject: [PATCH] io_uring: optimise req->ctx reloads
Git-commit: 9983028e7660a2cc5e58403d8ce29569dbf3162d
Patch-mainline: v5.16-rc1
References: bsc#1205205
Don't load req->ctx in advance, it takes an extra register and the field
stays valid even after opcode handlers. It also optimises out req->ctx
load in io_iopoll_req_issued() once it's inlined.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1e45ff671c44be0eb904f2e448a211734893fa0b.1634314022.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
---
fs/io_uring.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index a2f989e84583..5a4d13ad1277 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6588,7 +6588,6 @@ static void io_clean_op(struct io_kiocb *req)
static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
{
- struct io_ring_ctx *ctx = req->ctx;
const struct cred *creds = NULL;
int ret;
@@ -6715,7 +6714,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
if (ret)
return ret;
/* If the op doesn't have a file, we're not polling for it */
- if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file)
+ if ((req->ctx->flags & IORING_SETUP_IOPOLL) && req->file)
io_iopoll_req_issued(req);
return 0;
--
2.35.3