netdev - Re: [PATCH] ksmbd: server: avoid busy polling in accept loop

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Message-ID: <CAKYAXd9nkQFgXPpKpOY+O_B5HRLeyiZKO5a4X5MdfjYoO_O+Aw@mail.gmail.com>
Date: Thu, 30 Oct 2025 17:11:39 +0900
From: Namjae Jeon <linkinjeon@...nel.org>
To: Qingfang Deng <dqfext@...il.com>
Cc: Steve French <smfrench@...il.com>, Sergey Senozhatsky <senozhatsky@...omium.org>, 
	Tom Talpey <tom@...pey.com>, Ronnie Sahlberg <lsahlber@...hat.com>, Hyunchul Lee <hyc.lee@...il.com>, 
	linux-cifs@...r.kernel.org, linux-kernel@...r.kernel.org, 
	netdev@...r.kernel.org
Subject: Re: [PATCH] ksmbd: server: avoid busy polling in accept loop

On Thu, Oct 30, 2025 at 3:47 PM Qingfang Deng <dqfext@...il.com> wrote:
>
> The ksmbd listener thread was using busy waiting on a listening socket by
> calling kernel_accept() with SOCK_NONBLOCK and retrying every 100ms on
> -EAGAIN. Since this thread is dedicated to accepting new connections,
> there is no need for non-blocking mode.
>
> Switch to a blocking accept() call instead, allowing the thread to sleep
> until a new connection arrives. This avoids unnecessary wakeups and CPU
> usage.
>
> Also remove:
>   - TCP_NODELAY, which has no effect on a listening socket.
>   - sk_rcvtimeo and sk_sndtimeo assignments, which only caused accept()
>     to return -EAGAIN prematurely.
>
> Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers")
> Signed-off-by: Qingfang Deng <dqfext@...il.com>
Applied it to #ksmbd-for-next-next.
Thanks!