From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerin Jacob Subject: Re: [PATCH] doc: announce ABI change on ethdev Date: Tue, 9 May 2017 22:34:13 +0530 Message-ID: <20170509170412.GA14727@jerin> References: <20170501065812.5185-1-shahafs@mellanox.com> <20170509134004.GO16218@6wind.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Shahaf Shuler , Konstantin Ananyev , Olivier Matz , Tomasz Kulasek , dev@dpdk.org To: Adrien Mazarguil Return-path: Received: from NAM03-CO1-obe.outbound.protection.outlook.com (mail-co1nam03on0049.outbound.protection.outlook.com [104.47.40.49]) by dpdk.org (Postfix) with ESMTP id 15C9B4A63 for ; Tue, 9 May 2017 19:04:36 +0200 (CEST) Content-Disposition: inline In-Reply-To: <20170509134004.GO16218@6wind.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" -----Original Message----- > Date: Tue, 9 May 2017 15:40:04 +0200 > From: Adrien Mazarguil > To: Shahaf Shuler , Konstantin Ananyev > , Olivier Matz , > Tomasz Kulasek > Cc: dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH] doc: announce ABI change on ethdev > > On Mon, May 01, 2017 at 09:58:12AM +0300, Shahaf Shuler wrote: > > This is an ABI change notice for DPDK 17.08 in librte_ether > > about changes in rte_eth_txmode structure. > > > > Currently Tx offloads are enabled by default, and can be disabled > > using ETH_TXQ_FLAGS_NO* flags. This behaviour is not consistent with > > the Rx side where the Rx offloads are disabled by default and enabled > > according to bit field in rte_eth_rxmode structure. > > > > The proposal is to disable the Tx offloads by default, and provide > > a way for the application to enable them in rte_eth_txmode structure. > > Besides of making the Tx configuration API more consistent for > > applications, PMDs will be able to provide a better out of the > > box performance. > > Finally, as part of the work, the ETH_TXQ_FLAGS_NO* will > > be superseded as well. > > > > Signed-off-by: Shahaf Shuler > > Basically, TX mbuf flags like TSO and checksum offloads won't have to be > honored by PMDs unless applications request them first while configuring the > device, just like RX offloads. > > Considering more and more TX offloads will be added over time, I do not > think expecting them all to be enabled by default is sane. There will always > be an associated software cost in PMDs, and this solution allows > applications to selectively enable them as needed for maximum performance. > > Konstantin/Olivier/Tomasz, I do not want to resume the thread about > tx_prepare(), however this could provide an alternative means to benefit > from improved performance when applications do not need TSO (or any other > offload for that matter), while adding consistency to device configuration. > > What's your opinion? > > In any case I'm fine with this change: > > Acked-by: Adrien Mazarguil Acked-by: Jerin Jacob