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 X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA0F0C3A5A6 for ; Thu, 19 Sep 2019 13:07:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C30321907 for ; Thu, 19 Sep 2019 13:07:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="X52OAWbi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732270AbfISNHv (ORCPT ); Thu, 19 Sep 2019 09:07:51 -0400 Received: from mail-qk1-f194.google.com ([209.85.222.194]:37827 "EHLO mail-qk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730838AbfISNHv (ORCPT ); Thu, 19 Sep 2019 09:07:51 -0400 Received: by mail-qk1-f194.google.com with SMTP id u184so3288957qkd.4 for ; Thu, 19 Sep 2019 06:07:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Q8cnyfGfmzAjc9ImXRGBhM+FXEEv9+QulAkaTqqMuq0=; b=X52OAWbis3WGfxDzkDCwt9paOPvE4hB2l5oxhWiXbjRwZaajThKLWBHc32s31tcLnE 5G7/mDnP7+EVb8anXxPR78J/80hhqkmzI2LL+9skIawodfqkiffOI+RlWUCCzmfXupVP SXvKHSafnu4Sol/6VnCVazTtL82o/yU/OSSymcG1bojUhF3Dl+Ruv22Wu37h3mhcsdl7 dsyOMPS3dqha6YKvnTHlToY8oZBuGoYy0ZhxcSEBSx+ICv4/Mu0d09gbxLuDhrSHgNgR GKr1CEUlZNdoT0ZIjNCE6amC7jIWyqwm/Uuib9TSFe64tZAbL+Jcqti5dSway42j82NJ xTeA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Q8cnyfGfmzAjc9ImXRGBhM+FXEEv9+QulAkaTqqMuq0=; b=sgsEx0n6+PgoPn2mcuDm/AByhJ+fKen/ZURRtZLVJ+RQp10w0dI4Qe73MiQTy8xYRu MizQN4H//EJTpEXBon/8lwguvDBy3iL+w5SfVqMdQx956YPQ+wgTqundKspPEHC/asxO P0w+PnKfIfFytsYvzNAzEDg0yBQG9NIN+R/89AlubGDYzLC9ZFtUpN/tjYQmfNws+sjp uhB8PvKiSnwL67TbOcZ73W19wXwX43z/C75k5rlvB3acxbcZpZrugVbPrvTYluerbxi5 59q74lZjO1IW5L7nVjtuZ1SCPmdvBOvqZ7I3prq+DZcb7xHX6PRwrSA5GrXmL0N7K8G3 U6dA== X-Gm-Message-State: APjAAAXN6SJNJjnr7RNF6TjS2jPHXIYkjwafJdwgiO/XniEMVMLnX4V+ P31UoV+l7JzjPY1cSN/Bpc8F5SmRTXE= X-Google-Smtp-Source: APXvYqxhfoFkrcm/9C3A+W8PUKjbTii8b9ciEsen4mA/MbRav+V/5gp+eaLZDuYpKyUs1aZNWh1C5A== X-Received: by 2002:a37:a00d:: with SMTP id j13mr2877908qke.2.1568898470231; Thu, 19 Sep 2019 06:07:50 -0700 (PDT) Received: from localhost.localdomain ([168.181.48.215]) by smtp.gmail.com with ESMTPSA id r1sm3715617qti.4.2019.09.19.06.07.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 Sep 2019 06:07:49 -0700 (PDT) Received: by localhost.localdomain (Postfix, from userid 1000) id B930EC4A4F; Thu, 19 Sep 2019 10:07:46 -0300 (-03) Date: Thu, 19 Sep 2019 10:07:46 -0300 From: Marcelo Ricardo Leitner To: Willem de Bruijn Cc: Steffen Klassert , Network Development , Paolo Abeni Subject: Re: [PATCH RFC v3 0/5] Support fraglist GRO/GSO Message-ID: <20190919130746.GC3431@localhost.localdomain> References: <20190918072517.16037-1-steffen.klassert@secunet.com> <20190918165817.GA3431@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Sep 19, 2019 at 08:55:22AM -0400, Willem de Bruijn wrote: > On Wed, Sep 18, 2019 at 12:58 PM Marcelo Ricardo Leitner > wrote: > > > > On Wed, Sep 18, 2019 at 12:17:08PM -0400, Willem de Bruijn wrote: > > > On Wed, Sep 18, 2019 at 3:25 AM Steffen Klassert > > > wrote: > > > > > > > > This patchset adds support to do GRO/GSO by chaining packets > > > > of the same flow at the SKB frag_list pointer. This avoids > > > > the overhead to merge payloads into one big packet, and > > > > on the other end, if GSO is needed it avoids the overhead > > > > of splitting the big packet back to the native form. > > > > > > > > Patch 1 Enables UDP GRO by default. > > > > > > > > Patch 2 adds a netdev feature flag to enable listifyed GRO, > > > > this implements one of the configuration options discussed > > > > at netconf 2019. > > > > > > > > Patch 3 adds a netdev software feature set that defaults to off > > > > and assigns the new listifyed GRO feature flag to it. > > > > > > > > Patch 4 adds the core infrastructure to do fraglist GRO/GSO. > > > > > > > > Patch 5 enables UDP to use fraglist GRO/GSO if configured and no > > > > GRO supported socket is found. > > > > > > Very nice feature, Steffen. Aside from questions around performance, > > > my only question is really how this relates to GSO_BY_FRAGS. > > > > They do the exact same thing AFAICT: they GSO according to a > > pre-formatted list of fragments/packets, and not to a specific size > > (such as MSS). > > > > > > > > More specifically, whether we can remove that in favor of using your > > > new skb_segment_list. That would actually be a big first step in > > > simplifying skb_segment back to something manageable. > > > > The main issue (that I know) on obsoleting GSO_BY_FRAGS is that > > dealing with frags instead of frag_list was considered easier to be > > offloaded, if ever attempted. So this would be a step back on that > > aspect. Other than this, it should be doable. > > But GSO_BY_FRAGS also uses frag_list, not frags? /me is scratching his head. My bad. I thought it was already using frags. Thanks. > > And list_skb->len for mss. Which stands more for 'current frag size', yes. (list_skb, not head_skb)