From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 0A6687E75 for ; Thu, 4 Dec 2014 11:23:34 +0100 (CET) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga103.jf.intel.com with ESMTP; 04 Dec 2014 02:21:54 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,514,1413270000"; d="scan'208";a="618488905" Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by orsmga001.jf.intel.com with ESMTP; 04 Dec 2014 02:23:33 -0800 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.144]) by IRSMSX152.ger.corp.intel.com ([169.254.6.56]) with mapi id 14.03.0195.001; Thu, 4 Dec 2014 10:23:32 +0000 From: "Ananyev, Konstantin" To: "Liu, Jijiang" , Olivier MATZ Thread-Topic: [dpdk-dev] [PATCH v5 2/3] mbuf:add three TX ol_flags and repalce PKT_TX_VXLAN_CKSUM Thread-Index: AQHQDu5Csn4rdRtSMEuKWiThOnkfhJx9OYaAgAAV4YCAABxsgIABPOtwgACRSjA= Date: Thu, 4 Dec 2014 10:23:31 +0000 Message-ID: <2601191342CEEE43887BDE71AB977258213BC6F2@IRSMSX105.ger.corp.intel.com> References: <1417532767-1309-1-git-send-email-jijiang.liu@intel.com> <1417532767-1309-3-git-send-email-jijiang.liu@intel.com> <547EF6E9.5040000@6wind.com> <2601191342CEEE43887BDE71AB977258213BC46D@IRSMSX105.ger.corp.intel.com> <547F211B.3040905@6wind.com> <1ED644BD7E0A5F4091CF203DAFB8E4CC01D9FF2B@SHSMSX101.ccr.corp.intel.com> In-Reply-To: <1ED644BD7E0A5F4091CF203DAFB8E4CC01D9FF2B@SHSMSX101.ccr.corp.intel.com> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [163.33.239.180] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] [PATCH v5 2/3] mbuf:add three TX ol_flags and repalce PKT_TX_VXLAN_CKSUM X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 Dec 2014 10:23:35 -0000 > -----Original Message----- > From: Liu, Jijiang > Sent: Thursday, December 04, 2014 2:08 AM > To: Olivier MATZ > Cc: Ananyev, Konstantin; dev@dpdk.org > Subject: RE: [dpdk-dev] [PATCH v5 2/3] mbuf:add three TX ol_flags and rep= alce PKT_TX_VXLAN_CKSUM >=20 > Hi Olivier, >=20 >=20 > > -----Original Message----- > > From: Olivier MATZ [mailto:olivier.matz@6wind.com] > > Sent: Wednesday, December 3, 2014 10:42 PM > > To: Ananyev, Konstantin; Liu, Jijiang; dev@dpdk.org > > Subject: Re: [dpdk-dev] [PATCH v5 2/3] mbuf:add three TX ol_flags and r= epalce > > PKT_TX_VXLAN_CKSUM > > > > Hi Konstantin, > > > > On 12/03/2014 01:59 PM, Ananyev, Konstantin wrote: > > >> I still think having a flag IPV4 + another flag IP_CHECKSUM is not > > >> appropriate. > > > > > > Sorry, didn't get you here. > > > Are you talking about our discussion should PKT_TX_IP_CKSUM and > > PKT_TX_IPV4 be mutually exclusive or not? > > > > Yes > > > > >> I though Konstantin agreed on other flags, but I may have > > >> misunderstood: > > >> > > >> http://dpdk.org/ml/archives/dev/2014-November/009070.html > > > > > > In that mail, I was talking about my suggestion to make PKT_TX_IP_CK= SUM, > > PKT_TX_IPV4 and PKT_TX_IPV6 to occupy 2 bits. > > > Something like: > > > #define PKT_TX_IP_CKSUM (1 << X) > > > #define PKT_TX_IPV6 (2 << X) > > > #define PKT_TX_IPV4 (3 << X) > > > > > > "Even better, if we can squeeze these 3 flags into 2 bits. > > > Would save us 2 bits, plus might be handy, as in the PMD you can do: > > > > > > switch (ol_flags & TX_L3_MASK) { > > > case TX_IPV4: > > > ... > > > break; > > > case TX_IPV6: > > > ... > > > break; > > > case TX_IP_CKSUM: > > > ... > > > break; > > > }" > > > > > > As you pointed out, it will break backward compatibility. > > > I agreed with that and self-NACKed it. > > > > ok, so we are back between: > > > > 1/ (Jijiang's patch) > > PKT_TX_IP_CKSUM /* packet is IPv4, and we want hw cksum */ > > PKT_TX_IPV6 /* packet is IPv6 */ > > PKT_TX_IPV4 /* packet is IPv4, and we don't want hw cksum */ > > > > with PKT_TX_IP_CKSUM and PKT_TX_IPV4 exclusive > > > > and > > > > 2/ > > PKT_TX_IP_CKSUM /* we want hw IP cksum */ > > PKT_TX_IPV6 /* packet is IPv6 */ > > PKT_TX_IPV4 /* packet is IPv4 */ > > > > with PKT_TX_IP_CKSUM implies PKT_TX_IPV4 > > > > > > Solution 2/ looks better from a user point of view. Anyone else has an = opinion? >=20 > Let's think about these IPv4/6 flags in terms of checksum and IP version/= type, >=20 > 1. For IPv6 > IP checksum is meaningful only for IPv4, so we define 'PKT_TX_IPV6 = /* packet is IPv6 */' to tell driver/HW that this is IPV6 packet, > here we don't talk about the checksum for IPv6 as it is meaningless. Righ= t? >=20 > PKT_TX_IPV6 /* packet is IPv6 */ ------ IP type: v6; HW che= cksum: meaningless >=20 > 2. For IPv4, > My patch: >=20 > PKT_TX_IP_CKSUM /* packet is IPv4, and we want hw cksum */--------------= ------------IP type: v4; HW checksum: Yes > PKT_TX_IPV4 /* packet is IPv4, and we don't want hw cksum */ -------= ---------------- IP type: v4; HW checksum: No >=20 > You want: > PKT_TX_IP_CKSUM /* we want hw IP cksum */-------------------------- IP t= ype: v4; HW checksum: Yes > PKT_TX_IPV4 /* packet is IPv4*/ ------------------------ IP type: v= 4; HW checksum: yes or no? > = driver/HW don't know, just know this is packe= t with IPv4 header. > = HW checksum: meaningless?? Yep, that's why I also don't like that suggestion: PKT_TX_IPV4 itself doesn= 't contain all information. PMD will have to check PKT_TX_IP_CKSUM anyway. Konstantin >=20 > > Regards, > > Olivier