From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id 670D36841 for ; Mon, 11 Sep 2017 15:04:38 +0200 (CEST) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Sep 2017 06:04:08 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.42,377,1500966000"; d="scan'208";a="310308548" Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by fmsmga004.fm.intel.com with ESMTP; 11 Sep 2017 06:04:08 -0700 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.75]) by IRSMSX152.ger.corp.intel.com ([169.254.6.87]) with mapi id 14.03.0319.002; Mon, 11 Sep 2017 14:04:07 +0100 From: "Ananyev, Konstantin" To: "Hu, Jiayu" CC: "dev@dpdk.org" , "Kavanagh, Mark B" , "Tan, Jianfeng" Thread-Topic: [PATCH 2/5] gso/lib: add TCP/IPv4 GSO support Thread-Index: AQHTHOM2ld5YREF+cUG/0JFh8vSiiqKb+V+AgAgYxwCAAHtboIAA7xKAgApGJBA= Date: Mon, 11 Sep 2017 13:04:07 +0000 Message-ID: <2601191342CEEE43887BDE71AB9772584F249883@irsmsx105.ger.corp.intel.com> References: <1503584144-63181-1-git-send-email-jiayu.hu@intel.com> <1503584144-63181-3-git-send-email-jiayu.hu@intel.com> <2601191342CEEE43887BDE71AB9772584F23E097@IRSMSX103.ger.corp.intel.com> <20170904033150.GA9009@dpdk15.sh.intel.com> <2601191342CEEE43887BDE71AB9772584F244E8C@irsmsx105.ger.corp.intel.com> In-Reply-To: Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNWM4MzkxOTQtOGMxNy00ZTkxLTg4NjktMDVlMDA3ZTMyODhkIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE2LjUuOS4zIiwiVHJ1c3RlZExhYmVsSGFzaCI6ImpUaG5ORDRqVlwvZDM0eHR1cCtiWTIyREpvdm1kU2F2d0xEZXFVVnNuVUZrPSJ9 x-ctpclassification: CTP_IC dlp-product: dlpe-windows dlp-version: 11.0.0.116 dlp-reaction: no-action x-originating-ip: [163.33.239.182] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH 2/5] gso/lib: add TCP/IPv4 GSO support X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 11 Sep 2017 13:04:39 -0000 Hi Jiayu, > > > Linux supports two kinds of IP identifier: fixed identifier and incre= mental > > identifier, and > > > which one to use depends on upper protocol modules. Specifically, if = the > > protocol module > > > wants fixed identifiers, it will set SKB_GSO_TCP_FIXEDID to skb->gso_= type, > > and then > > > inet_gso_segment() will keep identifiers the same. Otherwise, all seg= ments > > will have > > > incremental identifiers. The reason for this design is that some prot= ocols > > may choose fixed > > > IP identifiers, like TCP (from RFC791). This design also shows that l= inux > > ignores the issue > > > of repeated IP identifiers. > > > > > > From the perspective of DPDK, we need to solve two problems. One is i= f > > ignore the issue of > > > repeated IP identifiers. The other is if the GSO library provides an = interface > > to upper > > > applications to enable them to choose fixed or incremental identifier= s, or > > simply uses > > > incremental IP identifiers. > > > > > > Do you have any suggestions? > > > > > > Do the same as Linux? > > I.E. add some flag RRE_GSO_IPID_FIXED (or so) into gso_ctx? >=20 > OK, I see. We can do that. >=20 > In the GRO library, we check if the IP identifiers are incremental compul= sorily. If we > enable fixed IP identifier in GSO, it seems we also need to change the GR= O library. > I mean ignore IP identifier when merge packets, and don't update the IP i= dentifier > for the merged packet. What do you think of it? I suppose we can, if there is a use-case for it. Konstantin >=20