Re: [dpdk-dev] [PATCH v4 0/2] enable protocol agnostic flow offloading in RSS

["Zhang, Qi Z" <qi.z.zhang@intel.com>]

> -----Original Message-----
> From: Xu, Ting <ting.xu@intel.com>
> Sent: Friday, November 5, 2021 10:54 PM
> To: Thomas Monjalon <thomas@monjalon.net>; Zhang, Qi Z
> <qi.z.zhang@intel.com>
> Cc: dev@dpdk.org; Yang, Qiming <qiming.yang@intel.com>; Guo, Junfeng
> <junfeng.guo@intel.com>; orika@nvidia.com; viacheslavo@nvidia.com;
> Yigit, Ferruh <ferruh.yigit@intel.com>; andrew.rybchenko@oktetlabs.ru
> Subject: RE: [dpdk-dev] [PATCH v4 0/2] enable protocol agnostic flow
> offloading in RSS
> 
> > -----Original Message-----
> > From: Thomas Monjalon <thomas@monjalon.net>
> > Sent: Friday, November 5, 2021 9:23 PM
> > To: Zhang, Qi Z <qi.z.zhang@intel.com>; Xu, Ting <ting.xu@intel.com>
> > Cc: dev@dpdk.org; Yang, Qiming <qiming.yang@intel.com>; Guo, Junfeng
> > <junfeng.guo@intel.com>; orika@nvidia.com; viacheslavo@nvidia.com;
> > Yigit, Ferruh <ferruh.yigit@intel.com>; andrew.rybchenko@oktetlabs.ru
> > Subject: Re: [dpdk-dev] [PATCH v4 0/2] enable protocol agnostic flow
> > offloading in RSS
> >
> > 05/11/2021 14:18, Xu, Ting:
> > > From: Thomas Monjalon <thomas@monjalon.net>
> > > > 04/11/2021 03:22, Ting Xu:
> > > > > Enable protocol agnostic flow offloading to support raw pattern
> > > > > input for RSS hash flow rule creation. It is based on Parser
> > > > > Library
> > feature.
> > > > > Current rte_flow raw API is utilized.
> > > >
> > > > I remember raw item was especially targetting encapsulation action.
> > > > Which action do you achieve in ice PMD? Only RSS with raw item?
> > > >
> > > > For matching, raw item is quite limited. I think the new flex item
> > > > is more appropriate for general custom protocol parsing.
> > > > Did you look into flex item feature?
> > > >
> > > Hi, Thomas, we make use of the API for rte_raw to achieve our
> > > protocol agnostic flow offloading method, including RSS and FDIR.
> > > Behind it is the new Parser Library feature based on DDP,
> >
> > Where is this parser library code?
> 
> Parser Library is committed before as ice base code.
> 
> >
> > > rather than the original logic I think.
> >
> > > Binary-format pattern spec and mask are passed to Parser Library and
> > > the corresponding protocol ID and offset will be provided.
> >
> > Sorry you didn't reply about the new flex item added in this release.
> > Do you know it was added?
> > 	https://git.dpdk.org/dpdk/commit/?id=dc4d860e8a89
> >
> 
> Protocol agnostic flow offloading is based on ice DDP feature, although
> they all want to make flow creation more flexible, I think it is different
> with flex item.
> @Zhang, Qi Z Hi, Qi, are you familiar with flex item?
> 

Yes, this is a very Intel DDP specific feature, the goal is to make our driver to support any customized parser (DDP) without change code.

Below steps are planned:

1. raw packet interface, this help on quick POC, as its simply the rte_flow parser, but of cause it's not scale for an DPDK application to support different vendor.
2. enable a build-in util to forge a packet from a sequence of rte_flow headers, then the application will be scale, but the missing part is how to describe a customized header, we have similar idea like json, but seems "Flex Item" already help to fix this gap, and we will improve the solution base on it.

Thanks
Qi