From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from stargate.chelsio.com (stargate.chelsio.com [12.32.117.8]) by dpdk.org (Postfix) with ESMTP id 35DB2379B for ; Thu, 1 Dec 2016 09:26:54 +0100 (CET) Received: from localhost (scalar.blr.asicdesigners.com [10.193.185.94]) by stargate.chelsio.com (8.13.8/8.13.8) with ESMTP id uB18Qa2e017132; Thu, 1 Dec 2016 00:26:37 -0800 Date: Thu, 1 Dec 2016 13:54:24 +0530 From: Rahul Lakkireddy To: Thomas Monjalon Cc: "dev@dpdk.org" , Stephen Hurd , Jan Medala , Jakub Palider , John Daley , Adrien Mazarguil , Alejandro Lucero , Harish Patil , Rasesh Mody , Jerin Jacob , Yuanhan Liu , Yong Wang , Tomasz Kulasek , "konstantin.ananyev@intel.com" , "olivier.matz@6wind.com" Message-ID: <20161201082422.GA5216@chelsio.com> References: <1477486575-25148-1-git-send-email-tomaszx.kulasek@intel.com> <1479922585-8640-1-git-send-email-tomaszx.kulasek@intel.com> <8317180.L80Qf11uiu@xps13> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8317180.L80Qf11uiu@xps13> User-Agent: Mutt/1.5.24 (2015-08-30) Subject: Re: [dpdk-dev] [PATCH v12 0/6] add Tx preparation 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, 01 Dec 2016 08:26:55 -0000 Hi Thomas, On Monday, November 11/28/16, 2016 at 16:33:06 +0530, Thomas Monjalon wrote: > We need attention of every PMD developers on this thread. > > Reminder of what Konstantin suggested: > " > - if the PMD supports TX offloads AND > - if to be able use any of these offloads the upper layer SW would have to: > * modify the contents of the packet OR > * obey HW specific restrictions > then it is a PMD developer responsibility to provide tx_prep() that would implement > expected modifications of the packet contents and restriction checks. > Otherwise, tx_prep() implementation is not required and can be safely set to NULL. > " > > I copy/paste also my previous conclusion: > > Before txprep, there is only one API: the application must prepare the > packets checksum itself (get_psd_sum in testpmd). > With txprep, the application have 2 choices: keep doing the job itself > or call txprep which calls a PMD-specific function. > The question is: does non-Intel drivers need a checksum preparation for TSO? > Will it behave well if txprep does nothing in these drivers? > > When looking at the code, most of drivers handle the TSO flags. > But it is hard to know whether they rely on the pseudo checksum or not. > > git grep -l 'PKT_TX_UDP_CKSUM\|PKT_TX_TCP_CKSUM\|PKT_TX_TCP_SEG' drivers/net/ > > drivers/net/bnxt/bnxt_txr.c > drivers/net/cxgbe/sge.c > drivers/net/e1000/em_rxtx.c > drivers/net/e1000/igb_rxtx.c > drivers/net/ena/ena_ethdev.c > drivers/net/enic/enic_rxtx.c > drivers/net/fm10k/fm10k_rxtx.c > drivers/net/i40e/i40e_rxtx.c > drivers/net/ixgbe/ixgbe_rxtx.c > drivers/net/mlx4/mlx4.c > drivers/net/mlx5/mlx5_rxtx.c > drivers/net/nfp/nfp_net.c > drivers/net/qede/qede_rxtx.c > drivers/net/thunderx/nicvf_rxtx.c > drivers/net/virtio/virtio_rxtx.c > drivers/net/vmxnet3/vmxnet3_rxtx.c > > Please, we need a comment for each driver saying > "it is OK, we do not need any checksum preparation for TSO" > or > "yes we have to implement tx_prepare or TSO will not work in this mode" For CXGBE PMD, "it is OK, we do not need any checksum preparation for TSO". Thanks, Rahul