linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Olivier Langlois <olivier@trillion01.com>
To: Jens Axboe <axboe@kernel.dk>,
	Pavel Begunkov <asml.silence@gmail.com>,
	io-uring@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Olivier Langlois <olivier@trillion01.com>
Subject: [PATCH v2 1/2] io_uring: Fix race condition when sqp thread goes to sleep
Date: Wed, 23 Jun 2021 11:50:11 -0700	[thread overview]
Message-ID: <d1419dc32ec6a97b453bee34dc03fa6a02797142.1624473200.git.olivier@trillion01.com> (raw)
In-Reply-To: <cover.1624473200.git.olivier@trillion01.com>

If an asynchronous completion happens before the task is preparing
itself to wait and set its state to TASK_INTERRUPTIBLE, the completion
will not wake up the sqp thread.

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
---
 fs/io_uring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index fc8637f591a6..7c545fa66f31 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6902,7 +6902,7 @@ static int io_sq_thread(void *data)
 		}
 
 		prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
-		if (!io_sqd_events_pending(sqd)) {
+		if (!io_sqd_events_pending(sqd) && !io_run_task_work()) {
 			needs_sched = true;
 			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
 				io_ring_set_wakeup_flag(ctx);
-- 
2.32.0


  reply	other threads:[~2021-06-23 18:50 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-23 18:50 [PATCH v2 0/2] Minor SQPOLL thread fix and improvement Olivier Langlois
2021-06-23 18:50 ` Olivier Langlois [this message]
2021-06-23 22:02   ` [PATCH v2 1/2] io_uring: Fix race condition when sqp thread goes to sleep Pavel Begunkov
2021-06-23 18:50 ` [PATCH v2 2/2] io_uring: Create define to modify a SQPOLL parameter Olivier Langlois
2021-06-23 22:14   ` Pavel Begunkov
2021-06-23 22:24     ` Jens Axboe
2021-06-23 23:39       ` Pavel Begunkov
2021-06-23 22:24 ` [PATCH v2 0/2] Minor SQPOLL thread fix and improvement Jens Axboe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=d1419dc32ec6a97b453bee34dc03fa6a02797142.1624473200.git.olivier@trillion01.com \
    --to=olivier@trillion01.com \
    --cc=asml.silence@gmail.com \
    --cc=axboe@kernel.dk \
    --cc=io-uring@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).