Re: [dpdk-dev] [PATCH 0/3] refresh NIC features matrix

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

> -----Original Message-----
> From: Thomas Monjalon <thomas@monjalon.net>
> Sent: Friday, March 20, 2020 6:45 PM
> To: Zhang, Qi Z <qi.z.zhang@intel.com>
> Cc: dev@dpdk.org; rahul.lakkireddy@chelsio.com; Wang, Xiao W
> <xiao.w.wang@intel.com>; xavier.huwei@huawei.com; Xing, Beilei
> <beilei.xing@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>; Yang, Qiming
> <qiming.yang@intel.com>; Ananyev, Konstantin
> <konstantin.ananyev@intel.com>; Yigit, Ferruh <ferruh.yigit@intel.com>;
> jerinj@marvell.com; rmody@marvell.com; shshaikh@marvell.com;
> maxime.coquelin@redhat.com; Ye, Xiaolong <xiaolong.ye@intel.com>
> Subject: Re: [PATCH 0/3] refresh NIC features matrix
> 
> 20/03/2020 06:35, Zhang, Qi Z:
> > Hi Thomas:
> >
> > From: Thomas Monjalon <thomas@monjalon.net>
> > >
> > > This series aims to clean-up the big table of ethdev features:
> > >   http://doc.dpdk.org/guides/nics/overview.html#id1
> > >
> > > We could reorganize the information in this table, maybe split it or
> > > add/remove some rows.
> > > Before going to such reorganization, we should clean it up.
> > >
> > > The first patch is fixing the look & size of the table with recent sphinx.
> > >
> > > The second and third patches are removing 8 columns which are
> > > clearly
> > > unneeded:
> > >   - bnx2x_vf
> > >   - bonding
> > >   - kni
> > >   - nfp_vf
> > >   - null
> > >   - ring
> > >   - softnic
> > >   - vdev_netvsc
> > >
> > > More columns can be removed by merging PF/VF and vector datapaths.
> > > If a feature cannot be supported in all cases, it should be marked
> > > as partially supported (P).
> > > If a feature is PF-specific (like flow control), that's OK to mark
> > > it fully supported because it's obviously impossible for VF.
> > > There are also some features which were probably marked in some
> > > columns and missed in its VF or vector counterpart.
> > > Please work to merge and drop these 16 columns:
> > >   - cxgbevf
> > >   - fm10k_vf
> > >   - hns3_vf
> > >   - i40e_vec
> > >   - i40e_vf
> > >   - i40e_vf_vec
> > >   - iavf_vec
> > >   - ice_vec
> > >   - igb_vf
> > >   - ixgbe_vec
> > >   - ixgbe_vf
> > >   - ixgbe_vf_vec
> > >   - octeontx2_vec
> > >   - octeontx2_vf
> > >   - qede_vf
> > >   - virtio_vec
> > >
> > > The total gain is to reduce the table size from 71 to 47 columns.
> >
> > I agree to remove all the column with "vec", since vector PMD can be
> regarded as a feature of the a PMD.
> > But I'm not sure if it is a good idea to merge VF and PF into one column.
> > From my view, for intel device, VF driver and PF driver just share the code,
> but they actually are running at two different context.
> > And likely they will support different feature, merge into one column may
> confuse our customer if they want to understand what exactly the PMD
> support.
> 
> I understand you have 2 different datapaths.
> My arguments are:
> 	- it is the same NIC

Yes, but one device can be polymorphic, ideally i40e and i40evf could be in two different folder, and the common part can be a library in driver/common/i40e.

> 	- you cannot summarize everything in a table
> 	- we have two many columns to make it readable

I don't think columns number is critical, typically user just need to focus on the first column and the specific driver's column, 
I guess it may not a big challenge to enable some filter by front end web technique?
> 
> I think the right solution is mark features as partially available (P), and give
> details in the driver guide documentation.
> 
> Can you please, at least, remove the "vec" columns, as a first step?

Sure, as I said, I agree to remove "vec".

Thanks
Qi

> Thanks
>