From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9DF0BC678D4 for ; Mon, 6 Mar 2023 13:31:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231184AbjCFNbF (ORCPT ); Mon, 6 Mar 2023 08:31:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229861AbjCFNbE (ORCPT ); Mon, 6 Mar 2023 08:31:04 -0500 Received: from mail-wm1-x336.google.com (mail-wm1-x336.google.com [IPv6:2a00:1450:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BE1B2E809; Mon, 6 Mar 2023 05:31:03 -0800 (PST) Received: by mail-wm1-x336.google.com with SMTP id l7-20020a05600c1d0700b003eb5e6d906bso5177262wms.5; Mon, 06 Mar 2023 05:31:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1678109461; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :sender:from:to:cc:subject:date:message-id:reply-to; bh=rhJH6/756BF4GI7cA8Nb7CM9sk6OwpwkOhKbYvpbmHM=; b=DB2ZV6xUSRRGkB15jEDEuA7m1VPT/zd3VQN7JmOLz0I3iYPbFY0RiPjDD27lwywaJk MT+LzDaPLUV5BovzFNDv3uZ2ALMsTlmvsf3HKHAUyqkRCRSw3pJm90rliE5wmOaE/uvy 8uDC+KvYPuRtUPOvr9LaGP1CoSHeb4RZOIi69seGQm59JhINktHoU/FxHRuZO3Zjlc63 LmyJK1FQJEdxlccM+Gl0dh9nq0KY/NquR1SNwgAlVTaO2PqtQawdX65AuQShs5DfK02V 0bVFzpDpJc70lJRjv5z4Qr/xEWx9lgURkYh/ul1grRkgOVvqbARmWLBHleAR3KhPrTAn zY9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678109461; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :sender:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=rhJH6/756BF4GI7cA8Nb7CM9sk6OwpwkOhKbYvpbmHM=; b=cwGUiuLD7UhNYG++AUzX2QvNT3S6FTP0uM4eyRz7i5i7dCHSQ2ALTEbBHGA5hXPAhm xHde+vaqfSqO1BaYunK/pE+tsNu8JFDSmHL7HZRmqXcGB+Vpe01ah0815zNANYbsRJnX XRjMFFLFh/+XvAvnz4Uo0CJb0Ar6ogEZRzfwAeWM8Us8I3iVAN4Ib8z0T36hJVKQCp2k EP2SX8kF4iCv1UjQ3NezMk7UjdGgiivMnQz9XtDmUI42AKPO0urAK/amT5h41yCyV7+E eRpifrsxotF3kBYlhNVmZrWnXjMi7pOcxW7tOHfdf1oht8ykTgEMmJxZIqT89xryryCU 3SXA== X-Gm-Message-State: AO0yUKUCHJX/BguPVfgBOUm3jiILGBQ4jp4e7I3JVThQXxxTE2kld4z7 sI8PEwZ0qP3NO4LO6jCjuUo= X-Google-Smtp-Source: AK7set9aQF5WOvWDUBJFs/JQ/968i5JidVqTKngMlI2EOuZw63Ixst878FeGMNVGHOxXOThC2TvPjg== X-Received: by 2002:a05:600c:468b:b0:3e2:589:2502 with SMTP id p11-20020a05600c468b00b003e205892502mr8731744wmo.28.1678109461414; Mon, 06 Mar 2023 05:31:01 -0800 (PST) Received: from [192.168.0.160] ([170.253.51.134]) by smtp.gmail.com with ESMTPSA id z26-20020a1c4c1a000000b003eb395a8280sm14071563wmf.37.2023.03.06.05.31.00 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 06 Mar 2023 05:31:01 -0800 (PST) Sender: Alejandro Colomar Message-ID: Date: Mon, 6 Mar 2023 14:30:59 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 Subject: Re: [PATCH manpages v2 1/2] udp.7: add UDP_SEGMENT Content-Language: en-US To: Willem de Bruijn , linux-man@vger.kernel.org Cc: mtk.manpages@gmail.com, pabeni@redhat.com, netdev@vger.kernel.org, Willem de Bruijn References: <20230302154808.2139031-1-willemdebruijn.kernel@gmail.com> From: Alejandro Colomar In-Reply-To: <20230302154808.2139031-1-willemdebruijn.kernel@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Willem, On 3/2/23 16:48, Willem de Bruijn wrote: > From: Willem de Bruijn > > UDP_SEGMENT was added in commit bec1f6f69736 > ("udp: generate gso with UDP_SEGMENT") > > $ git describe --contains bec1f6f69736 > linux/v4.18-rc1~114^2~377^2~8 > > Kernel source has example code in tools/testing/selftests/net/udpgso* > > Per https://www.kernel.org/doc/man-pages/patches.html, > "Describe how you obtained the information in your patch": > I am the author of the above commit and follow-ons. > > Signed-off-by: Willem de Bruijn > It doesn't apply. Can you please rebase on top of master? Thanks, Alex > --- > > Changes v1->v2 > - semantic newlines: also break on comma and colon > - remove bold: section number following function name > - add bold: special macro USHRT_MAX > --- > man7/udp.7 | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/man7/udp.7 b/man7/udp.7 > index 5822bc551fdf..6646c1e96bb0 100644 > --- a/man7/udp.7 > +++ b/man7/udp.7 > @@ -204,6 +204,34 @@ portable. > .\" UDP_ENCAP_ESPINUDP draft-ietf-ipsec-udp-encaps-06 > .\" UDP_ENCAP_L2TPINUDP rfc2661 > .\" FIXME Document UDP_NO_CHECK6_TX and UDP_NO_CHECK6_RX, added in Linux 3.16 > +.TP > +.BR UDP_SEGMENT " (since Linux 4.18)" > +Enables UDP segmentation offload. > +Segmentation offload reduces > +.BR send (2) > +cost by transferring multiple datagrams worth of data as a single large > +packet through the kernel transmit path, > +even when that exceeds MTU. > +As late as possible, > +the large packet is split by segment size into a series of datagrams. > +This segmentation offload step is deferred to hardware if supported, > +else performed in software. > +This option takes a value between 0 and > +.BR USHRT_MAX > +that sets the segment size: > +the size of datagram payload, > +excluding the UDP header. > +The segment size must be chosen such that at most 64 datagrams are sent in > +a single call and that the datagrams after segmentation meet the same MTU > +rules that apply to datagrams sent without this option. > +Segmentation offload depends on checksum offload, > +as datagram checksums are computed after segmentation. > +The option may also be set for individual > +.BR sendmsg (2) > +calls by passing it as a > +.BR cmsg (7). > +A value of zero disables the feature. > +This option should not be used in code intended to be portable. > .SS Ioctls > These ioctls can be accessed using > .BR ioctl (2).