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 26BCC95DC for ; Tue, 2 Feb 2016 14:49:57 +0100 (CET) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga103.jf.intel.com with ESMTP; 02 Feb 2016 05:49:55 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,384,1449561600"; d="scan'208";a="903863938" Received: from irsmsx151.ger.corp.intel.com ([163.33.192.59]) by orsmga002.jf.intel.com with ESMTP; 02 Feb 2016 05:49:54 -0800 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.237]) by IRSMSX151.ger.corp.intel.com ([169.254.4.108]) with mapi id 14.03.0248.002; Tue, 2 Feb 2016 13:49:53 +0000 From: "Ananyev, Konstantin" To: "Kulasek, TomaszX" , "dev@dpdk.org" Thread-Topic: [dpdk-dev] [PATCH 1/2] ethdev: add buffered tx api Thread-Index: AQHRT6NgF5mTPTzM9EGbrlxNGe76s57822EQgBvGfYCAAD2l4A== Date: Tue, 2 Feb 2016 13:49:52 +0000 Message-ID: <2601191342CEEE43887BDE71AB97725836B024AC@irsmsx105.ger.corp.intel.com> References: <1452869038-9140-1-git-send-email-tomaszx.kulasek@intel.com> <1452869038-9140-2-git-send-email-tomaszx.kulasek@intel.com> <2601191342CEEE43887BDE71AB97725836AE637C@irsmsx105.ger.corp.intel.com> <3042915272161B4EB253DA4D77EB373A14E440C3@IRSMSX102.ger.corp.intel.com> In-Reply-To: <3042915272161B4EB253DA4D77EB373A14E440C3@IRSMSX102.ger.corp.intel.com> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [163.33.239.181] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH 1/2] ethdev: add buffered tx api 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: Tue, 02 Feb 2016 13:49:57 -0000 Hi Tomasz, > -----Original Message----- > From: Kulasek, TomaszX > Sent: Tuesday, February 02, 2016 10:01 AM > To: Ananyev, Konstantin; dev@dpdk.org > Subject: RE: [dpdk-dev] [PATCH 1/2] ethdev: add buffered tx api >=20 > Hi Konstantin, >=20 > > -----Original Message----- > > From: Ananyev, Konstantin > > Sent: Friday, January 15, 2016 19:45 > > To: Kulasek, TomaszX; dev@dpdk.org > > Subject: RE: [dpdk-dev] [PATCH 1/2] ethdev: add buffered tx api > > > > Hi Tomasz, > > > > > > > > + /* get new buffer space first, but keep old space around */ > > > + new_bufs =3D rte_zmalloc("ethdev->txq_bufs", > > > + sizeof(*dev->data->txq_bufs) * nb_queues, 0); > > > + if (new_bufs =3D=3D NULL) > > > + return -(ENOMEM); > > > + > > > > Why not to allocate space for txq_bufs together with tx_queues (as one > > chunk for both)? > > As I understand there is always one to one mapping between them anyway. > > Would simplify things a bit. > > Or even introduce a new struct to group with all related tx queue info > > togetehr struct rte_eth_txq_data { > > void *queue; /*actual pmd queue*/ > > struct rte_eth_dev_tx_buffer buf; > > uint8_t state; > > } > > And use it inside struct rte_eth_dev_data? > > Would probably give a better data locality. > > >=20 > Introducing such a struct will require a huge rework of pmd drivers. I do= n't think it's worth only for this one feature. Why not? Things are getting more and more messy here: now we have a separate array o= f pointer to queues, Separate array of queue states, you are going to add separate array of tx b= uffers. For me it seems logical to unite all these 3 fields into one sub-struct.=20 >=20 >=20 > > > +/** > > > + * @internal > > > + * Structure used to buffer packets for future TX > > > + * Used by APIs rte_eth_tx_buffer and rte_eth_tx_buffer_flush */ > > > +struct rte_eth_dev_tx_buffer { > > > + struct rte_mbuf *pkts[RTE_ETHDEV_TX_BUFSIZE]; > > > > I think it is better to make size of pkts[] configurable at runtime. > > There are a lot of different usage scenarios - hard to predict what wou= ld > > be an optimal buffer size for all cases. > > >=20 > This buffer is allocated in eth_dev shared memory, so there are two scena= rios: > 1) We have prealocated buffer with maximal size, and then we can set thre= shold level without restarting device, or > 2) We need to set its size before starting device. >=20 > Second one is better, I think. Yep, I was thinking about 2) too. Might be an extra parameter in struct rte_eth_txconf. >=20 > Tomasz