From: Pavel Begunkov <asml.silence@gmail.com>
Date: Tue, 13 Oct 2020 08:43:58 +0000 (+0100)
Subject: io_uring: don't put a poll req under spinlock
X-Git-Tag: v5.10.7~1266^2~39
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6a0af224c21309f24dbb1b79d0744b255d7156a0;p=platform%2Fkernel%2Flinux-rpi.git

io_uring: don't put a poll req under spinlock

Move io_put_req() in io_poll_task_handler() from under spinlock. This
eliminates the need to use REQ_F_COMP_LOCKED, at the expense of
potentially having to grab the lock again. That's still a better trade
off than relying on the locked flag.

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 ca9be31..92546f9 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -4844,10 +4844,9 @@ static void io_poll_task_handler(struct io_kiocb *req, struct io_kiocb **nxt)
 
 	hash_del(&req->hash_node);
 	io_poll_complete(req, req->result, 0);
-	req->flags |= REQ_F_COMP_LOCKED;
-	*nxt = io_put_req_find_next(req);
 	spin_unlock_irq(&ctx->completion_lock);
 
+	*nxt = io_put_req_find_next(req);
 	io_cqring_ev_posted(ctx);
 }