-----Original Message----- > Date: Mon, 30 Jul 2018 14:12:12 +0000 > From: "Ananyev, Konstantin" <konstantin.anan...@intel.com> > To: Jerin Jacob <jerin.ja...@caviumnetworks.com> > CC: Thomas Monjalon <tho...@monjalon.net>, "dev@dpdk.org" <dev@dpdk.org>, > "Yigit, Ferruh" <ferruh.yi...@intel.com>, "shah...@mellanox.com" > <shah...@mellanox.com> > Subject: RE: [dpdk-dev] [PATCH] examples: remove Rx checksum offload > > > > > > -----Original Message----- > > > Date: Mon, 30 Jul 2018 11:00:02 +0000 > > > From: "Ananyev, Konstantin" <konstantin.anan...@intel.com> > > > To: Thomas Monjalon <tho...@monjalon.net>, Jerin Jacob > > > <jerin.ja...@caviumnetworks.com> > > > CC: "dev@dpdk.org" <dev@dpdk.org>, "Yigit, Ferruh" > > > <ferruh.yi...@intel.com>, "shah...@mellanox.com" <shah...@mellanox.com> > > > Subject: RE: [dpdk-dev] [PATCH] examples: remove Rx checksum offload > > > > > > External Email > > > > > > > -----Original Message----- > > > > From: Thomas Monjalon [mailto:tho...@monjalon.net] > > > > Sent: Monday, July 30, 2018 10:51 AM > > > > To: Jerin Jacob <jerin.ja...@caviumnetworks.com>; Ananyev, Konstantin > > > > <konstantin.anan...@intel.com> > > > > Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yi...@intel.com>; > > > > shah...@mellanox.com > > > > Subject: Re: [dpdk-dev] [PATCH] examples: remove Rx checksum offload > > > > > > > > 30/07/2018 11:35, Jerin Jacob: > > > > > From: "Ananyev, Konstantin" <konstantin.anan...@intel.com> > > > > > > > > > > > > > > As of now, application does not check PKT_RX_*_CKSUM_* flags per > > > > > > > packet, so it does not matter DEV_RX_OFFLOAD_CHECKSUM enabled or > > > > > > > not. > > > > > > > > > > > > > > Removing DEV_RX_OFFLOAD_CHECKSUM offload so that driver can save > > > > > > > a few > > > > > > > cycles if possible. > > > > > > > > > > > > Personally, I'd move in other direction: keep RX checksum offload > > > > > > and add > > > > > > checks inside sample apps to handle (drop) packets with invalid > > > > > > checksum. > > > > > > > > > > OK. Till someones add the DROP logic in application, Can we take > > > > > this patch? Because there is no point in enabling > > > > > DEV_RX_OFFLOAD_CHECKSUM > > > > > without DROP or any meaning full action in application. > > > > > > Probably, but at least it gives users a right estimation how long the > > > proper > > > RX/TX routine would take. > > > > For estimation, application can add any flag they want in local setup. > > It does not need to be upstream with out feature complete. > > > > > From other side what the point to disable these flags now, if we know that > > > > At least nicvf Rx routines are crafted based DEV_RX_OFFLOAD_CHECKSUM > > flags. If driver Rx routine crafted such case it will be useful. > > > > > we are doing wrong thing and will have to re-enable them again in future? > > > > But it is not correct now either. Right? > > Yes, right now invalid cksum information is simply ignored. > As you pointed - some PMD select RX routine based on checksum offload flags. > Yes, removing these flags might produce better performance numbers. > But from my perspective - it would be an artificial and temporary improvement, > as for l3fwd like apps we'll need to revert it back and add code to drop > invalid packets.
IMO, It is OK get a performance hit when do that support in l3fwd. There is no harm in removing the DEV_RX_OFFLOAD_CHECKSUM flag for now and it is correct from application perspective.(you are enabling an offload when you are using it, else don't enable it. I believe, this was philosophy for enabling Rx/Tx offloads) Since it is going in circles, I leave decision to ethdev maintainers. > Konstantin > > > > > > > > > > > > > > If there is no patch sent to use this offload on August 1st, > > > > then I will apply this patch to remove the offload request. > > > > > > > > > > Isn't it too late to do such things right now? > > > We are in RC3 stage and doesn't look like a critical issue. > > > > Yes. We can add it when have we proper fix. Currently, it signaling a wrong > > interpretation to application. > > > > > > > Konstantin > > > > > >
