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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 21072C4CEC4 for ; Wed, 18 Sep 2019 19:31:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E7513224BF for ; Wed, 18 Sep 2019 19:31:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="DoW2evWr"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="IhwungRm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731345AbfIRTb2 (ORCPT ); Wed, 18 Sep 2019 15:31:28 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:41018 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726676AbfIRTb2 (ORCPT ); Wed, 18 Sep 2019 15:31:28 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 490C561515; Wed, 18 Sep 2019 19:31:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1568835087; bh=GQ9PWHWoNFmoNwP5Ff8xmLoLlYzHhmoeyH7kt5bWxlY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=DoW2evWrM0ixe8eQE/GaN1BFm/PidoR0huH+O7qc4Lj5IMlgEWMHMo/4Wv9WxGfbm fGOEFRRmiZ0yQ3gZbym1bqhzJZplIJixNTaELwRKcE1L2pWNEMMIlroDrqkjcFwU/V F+dTsgb8idv1zjnWwSKt2OK47hdGL9Czqdp3cUr0= Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 4E00B602F2; Wed, 18 Sep 2019 19:31:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1568835086; bh=GQ9PWHWoNFmoNwP5Ff8xmLoLlYzHhmoeyH7kt5bWxlY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=IhwungRmSNTm2D8wKL2dj3iY5z1JBPtqZB9ktJRU4rDAwhzKzEUTnbIVupngRlHMM LPQVvw8Vd+1tnUtWdvi7gMnDTq0eTTV3HK88tYL1wzvi4NQZIPGkbOrRxuK9fP0Vcx ljb9bwEoms7IHgrfCRS0Yu0RE1CNoqsx+7wJ8Sac= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 18 Sep 2019 13:31:26 -0600 From: Subash Abhinov Kasiviswanathan To: Marcelo Ricardo Leitner Cc: Willem de Bruijn , Steffen Klassert , Network Development , Paolo Abeni Subject: Re: [PATCH RFC v3 0/5] Support fraglist GRO/GSO In-Reply-To: <20190918165817.GA3431@localhost.localdomain> References: <20190918072517.16037-1-steffen.klassert@secunet.com> <20190918165817.GA3431@localhost.localdomain> Message-ID: <621219c0a965d6ccc05b80081218ff7e@codeaurora.org> X-Sender: subashab@codeaurora.org User-Agent: Roundcube Webmail/1.2.5 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 2019-09-18 10:58, 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. Is there an existing userspace interface for GSO_BY_FRAGS for UDP? Per my understanding, the current UDP_GSO CMSG option only allows for a specific GSO_SIZE segmentation. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project