Re: [patch] socket.7: document SO_INCOMING_NAPI_ID - Michael Kerrisk (man-pages)

From: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
To: Sridhar Samudrala <sridhar.samudrala@intel.com>,
	linux-man@vger.kernel.org, netdev@vger.kernel.org
Cc: mtk.manpages@gmail.com
Subject: Re: [patch] socket.7: document SO_INCOMING_NAPI_ID
Date: Wed, 28 Oct 2020 07:13:03 +0100	[thread overview]
Message-ID: <b3df59a9-a2c3-20c8-7563-e974e596dd2a@gmail.com> (raw)
In-Reply-To: <1603847722-29024-1-git-send-email-sridhar.samudrala@intel.com>

On 10/28/20 2:15 AM, Sridhar Samudrala wrote:
> Add documentation for SO_INCOMING_NAPI_ID in socket.7 man page.

Hello Sridhar,

Thank you!

Would it be possible for you to resubmit the patch, with a commit
message that says how you obtained or verified the information.
This info is useful for review, but also for understand changes
when people look at the history in the future.

Also, please start new sentences on new lines (so-called
semantic newlines).

Thanks,

Michael

> Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
> ---
>  man7/socket.7 | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/man7/socket.7 b/man7/socket.7
> index 850d3162f..1f38273e9 100644
> --- a/man7/socket.7
> +++ b/man7/socket.7
> @@ -519,6 +519,18 @@ This provides optimal NUMA behavior and keeps CPU caches hot.
>  .\" SO_REUSEPORT logic, selecting the socket to receive the packet, ignores
>  .\" SO_INCOMING_CPU setting.
>  .TP
> +.BR SO_INCOMING_NAPI_ID " (gettable since Linux 4.12)"
> +.\" getsockopt 6d4339028b350efbf87c61e6d9e113e5373545c9
> +Returns a system level unique ID called NAPI ID that is associated with a RX
> +queue on which the last packet associated with that socket is received.
> +.IP
> +This can be used by an application to split the incoming flows among worker
> +threads based on the RX queue on which the packets associated with the flows
> +are received. It allows each worker thread to be associated with a NIC HW
> +receive queue and service all the connection requests received on that RX
> +queue. This mapping between a app thread and a HW NIC queue streamlines the
> +flow of data from the NIC to the application.
> +.TP
>  .B SO_KEEPALIVE
>  Enable sending of keep-alive messages on connection-oriented sockets.
>  Expects an integer boolean flag.
> 

-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/