Re: [RFC v2] current devlink extension plan for NICs

["Samudrala, Sridhar" <sridhar.samudrala@intel.com>]

On 5/1/2020 2:14 AM, Jiri Pirko wrote:
> Hi all.
> 
> First, I would like to apologize for very long email. But I think it
> would be beneficial to the see the whole picture, where we are going.
> 
> Currently we are working internally on several features with
> need of extension of the current devlink infrastructure. I took a stab
> at putting it all together in a single txt file, inlined below.
> 
> Most of the stuff is based on a new port sub-object called "func"
> (called "slice" previously" and "subdev" originally in Yuval's patchsets
> sent some while ago).
> 
> The text describes how things should behave and provides a draft
> of user facing console input/outputs. I think it is important to clear
> that up before we go in and implement the devlink core and
> driver pieces.
> 
> I would like to ask you to read this and comment. Especially, I would
> like to ask vendors if what is described fits the needs of your
> NIC/e-switch.
> 
> Please note that something is already implemented, but most of this
> isn't (see "what needs to be implemented" section).
> 
> v1->v2
> - mainly move from separate slice object into port/func subobject
> - couple of small fixes here and there
> 

<snip>

> 
> 
> 
> ==================================================================
> ||                                                              ||
> ||             Port func user cmdline API draft                 ||
> ||                                                              ||
> ==================================================================
> 
> Note that some of the "devlink port" attributes may be forgotten or misordered.
> 
> Funcs are created as sub-objects of ports where it makes sense to have them
> The driver takes care of that. The "func" is a handle to configure "the other
> side of the wire". The original port object has port leve properties,
> the new "func" sub-object on the other hand has device level properties".
> 
> This is example for the HOST A from the example above:
> 
> $ devlink port show
> pci/0000:06:00.0/0: flavour physical pfnum 0 type eth netdev enp6s0f0np1
> pci/0000:06:00.0/1: flavour physical pfnum 1 type eth netdev enp6s0f0np2
> pci/0000:06:00.0/2: flavour pcipf pfnum 2 type eth netdev enp6s0pf2
>                      func: hw_addr 10:22:33:44:55:66 state active
> pci/0000:06:00.0/3: flavour pcivf pfnum 2 vfnum 0 type eth netdev enp6s0pf2vf0
>                      func: hw_addr 10:22:33:44:55:77 state active
> pci/0000:06:00.0/4: flavour pcivf pfnum 0 vfnum 0 type eth netdev enp6s0pf0vf0
>                      func: hw_addr 10:22:33:44:55:88 state active
> pci/0000:06:00.0/5: flavour pcisf pfnum 0 sfnum 1 type eth netdev enp6s0pf0sf1
>                      func: hw_addr 10:22:33:44:55:99 state active
> pci/0000:06:00.0/6: flavour pcivf pfnum 1 vfnum 2 type nvme
>                      func: state active


I am trying to understand how the current implementation of 'devlink 
port' is being refactored to support this new model.

Today 'devlink port show' on a system with 2 port mlx5 NIC with 1 VFs 
created on each PF shows

pci/0000:af:00.0/1: type eth netdev enp175s0f0np0 flavour physical port 0
pci/0000:af:00.1/1: type eth netdev enp175s0f1np1 flavour physical port 1
pci/0000:af:00.2/1: type eth netdev enp175s0f2np0 flavour virtual port 0
pci/0000:af:08.2/1: type eth netdev enp175s8f2np0 flavour virtual port 0


Can you tell me how this will be represented in the new model?

It looks like you are assigning a pfnum to physical port as well as PCI 
PF. However, i am little confused as both pfnum 0 and pfnum 1 which seem 
to be 2 physical ports have the same bus/dev/func 06:00.0 and also the 
VF ports.

Thanks
Sridhar