linux-kernel - Re: [PATCH v5 4/6] io_uring: use io_ring_submit_lock() in io_iopoll_req

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAJnrk1YD=6qpZHRw31X4SRWGZcCraYzfSd0QjOuRg8HcsP+axA@mail.gmail.com>
Date: Tue, 16 Dec 2025 08:34:13 +0800
From: Joanne Koong <joannelkoong@...il.com>
To: Caleb Sander Mateos <csander@...estorage.com>
Cc: Jens Axboe <axboe@...nel.dk>, io-uring@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v5 4/6] io_uring: use io_ring_submit_lock() in io_iopoll_req_issued()

On Tue, Dec 16, 2025 at 4:10 AM Caleb Sander Mateos
<csander@...estorage.com> wrote:
>
> Use the io_ring_submit_lock() helper in io_iopoll_req_issued() instead
> of open-coding the logic. io_ring_submit_unlock() can't be used for the
> unlock, though, due to the extra logic before releasing the mutex.
>
> Signed-off-by: Caleb Sander Mateos <csander@...estorage.com>

This looks good to me.

Reviewed-by: Joanne Koong <joannelkoong@...il.com>

> ---
>  io_uring/io_uring.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
> index 6d6fe5bdebda..40582121c6a7 100644
> --- a/io_uring/io_uring.c
> +++ b/io_uring/io_uring.c
> @@ -1670,15 +1670,13 @@ void io_req_task_complete(struct io_tw_req tw_req, io_tw_token_t tw)
>   * accessing the kiocb cookie.
>   */
>  static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags)
>  {
>         struct io_ring_ctx *ctx = req->ctx;
> -       const bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
>
>         /* workqueue context doesn't hold uring_lock, grab it now */
> -       if (unlikely(needs_lock))
> -               mutex_lock(&ctx->uring_lock);
> +       io_ring_submit_lock(ctx, issue_flags);
>
>         /*
>          * Track whether we have multiple files in our lists. This will impact
>          * how we do polling eventually, not spinning if we're on potentially
>          * different devices.
> @@ -1701,11 +1699,11 @@ static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags)
>         if (READ_ONCE(req->iopoll_completed))
>                 wq_list_add_head(&req->comp_list, &ctx->iopoll_list);
>         else
>                 wq_list_add_tail(&req->comp_list, &ctx->iopoll_list);
>
> -       if (unlikely(needs_lock)) {
> +       if (unlikely(issue_flags & IO_URING_F_UNLOCKED)) {
>                 /*
>                  * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
>                  * in sq thread task context or in io worker task context. If
>                  * current task context is sq thread, we don't need to check
>                  * whether should wake up sq thread.
> --
> 2.45.2
>