Re: [dpdk-dev] [PATCH v2 1/4] ethdev: add Rx offload outer UDP checksum definition

[Jerin Jacob <jerin.jacob@caviumnetworks.com>]

-----Original Message-----
> Date: Mon, 8 Oct 2018 09:12:34 +0100
> From: Ferruh Yigit <ferruh.yigit@intel.com>
> To: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>, Jerin Jacob
>  <jerin.jacob@caviumnetworks.com>, Thomas Monjalon <thomas@monjalon.net>
> CC: Andrew Rybchenko <arybchenko@solarflare.com>, "Lu, Wenzhuo"
>  <wenzhuo.lu@intel.com>, "Wu, Jingjing" <jingjing.wu@intel.com>,
>  "Iremonger, Bernard" <bernard.iremonger@intel.com>, "Mcnamara, John"
>  <john.mcnamara@intel.com>, "Kovacevic, Marko" <marko.kovacevic@intel.com>,
>  Olivier Matz <olivier.matz@6wind.com>, "dev@dpdk.org" <dev@dpdk.org>,
>  "shahafs@mellanox.com" <shahafs@mellanox.com>, "didier.pallard@6wind.com"
>  <didier.pallard@6wind.com>
> Subject: Re: [dpdk-dev] [PATCH v2 1/4] ethdev: add Rx offload outer UDP
>  checksum definition
> User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101
>  Thunderbird/52.9.1
> 
> 
> On 10/6/2018 1:18 PM, Ananyev, Konstantin wrote:
> >
> >
> >> -----Original Message-----
> >> From: Jerin Jacob [mailto:jerin.jacob@caviumnetworks.com]
> >> Sent: Saturday, October 6, 2018 9:16 AM
> >> To: Thomas Monjalon <thomas@monjalon.net>
> >> Cc: Yigit, Ferruh <ferruh.yigit@intel.com>; Andrew Rybchenko <arybchenko@solarflare.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>; Wu,
> >> Jingjing <jingjing.wu@intel.com>; Iremonger, Bernard <bernard.iremonger@intel.com>; Mcnamara, John <john.mcnamara@intel.com>;
> >> Kovacevic, Marko <marko.kovacevic@intel.com>; Olivier Matz <olivier.matz@6wind.com>; dev@dpdk.org; shahafs@mellanox.com;
> >> Ananyev, Konstantin <konstantin.ananyev@intel.com>; didier.pallard@6wind.com
> >> Subject: Re: [dpdk-dev] [PATCH v2 1/4] ethdev: add Rx offload outer UDP checksum definition
> >>
> >> -----Original Message-----
> >>> Date: Sat, 06 Oct 2018 00:44:52 +0200
> >>> From: Thomas Monjalon <thomas@monjalon.net>
> >>> To: Ferruh Yigit <ferruh.yigit@intel.com>, Jerin Jacob
> >>>  <jerin.jacob@caviumnetworks.com>, Andrew Rybchenko
> >>>  <arybchenko@solarflare.com>
> >>> Cc: Wenzhuo Lu <wenzhuo.lu@intel.com>, Jingjing Wu <jingjing.wu@intel.com>,
> >>>  Bernard Iremonger <bernard.iremonger@intel.com>, John McNamara
> >>>  <john.mcnamara@intel.com>, Marko Kovacevic <marko.kovacevic@intel.com>,
> >>>  Olivier Matz <olivier.matz@6wind.com>, dev@dpdk.org, shahafs@mellanox.com,
> >>>  "Ananyev, Konstantin" <konstantin.ananyev@intel.com>,
> >>>  didier.pallard@6wind.com
> >>> Subject: Re: [dpdk-dev] [PATCH v2 1/4] ethdev: add Rx offload outer UDP
> >>>  checksum definition
> >>>
> >>>
> >>> 05/10/2018 22:04, Ferruh Yigit:
> >>>> On 10/4/2018 6:59 AM, Jerin Jacob wrote:
> >>>>> From: Andrew Rybchenko <arybchenko@solarflare.com>
> >>>>>> On 03.10.2018 21:14, Jerin Jacob wrote:
> >>>>>>> From: Andrew Rybchenko <arybchenko@solarflare.com>
> >>>>>>>> On 03.10.2018 20:12, Jerin Jacob wrote:
> >>>>>>>>> From: Jerin Jacob <jerin.jacob@caviumnetworks.com>
> >>>>>>>>>> From: Andrew Rybchenko <arybchenko@solarflare.com>
> >>>>>>>>>>> 3. PKT_RX_L4_CKSUM_MASK description says nothing if it is inner or outer.
> >>>>>>>>>>>      May be it is not directly related to changeset, but I think it would be really
> >>>>>>>>>>>      useful to clarify it.
> >>>>>>>>>> I will update the comment.
> >>>>>>>>> Hi Andrew,
> >>>>>>>>>
> >>>
> >>> However, we should re-visit the flag PKT_RX_EIP_CKSUM_BAD.
> >>
> >> Do we need to block this patch due to the exiting PKT_RX_EIP_CKSUM_BAD
> >> definition?
> >>
> >> I already added the author of the PKT_RX_EIP_CKSUM_BAD flag and ethdev and mbuf
> >> maintainers in this list. So what else I need make forward progress
> >> on this patch?
> >>
> >> I think, the definition of PKT_RX_EIP_CKSUM_BAD based on HW capability. It
> >> is safe to assume that ALL HW can support CKSUM BAD if the feature is
> >> available and hence it is more portable.
> >
> > Yes, as I remember PKT_RX_EIP_CKSUM_BAD is based on DEV_RX_OFFLOAD_OUTER_IPV4_CKSUM.
> 
> Switching to two bit won't reduce the portability, HW supports only reporting
> CKSUM_BAD can set BAD || UNKNOWN.

UNKNOWN is not a bit. It is represented as 0. It spec has 2 bit, then
driver need to report GOOD as well.

Same applies for PKT_RX_EL4_CKSUM as well.

> 
> And I think patch is not blocked by PKT_RX_EIP_CKSUM_BAD, it can be changed
> separately, for this patch question is can we represent PKT_RX_EL4_CKSUM_* with
> two bits, to have BAD/GOOD/UNKNOWN?