[dpdk-dev] [PATCH v8 00/25] Support VFD on i40e

[JOSHI, KAUSTUBH (KAUSTUBH)]

Hi Vincent, 

Greetings! Jumping into this debate a bit late, but let me share our point of view based on how we are using this code within AT&T for our NFV cloud. 

Actually, we first started with trying to do the configuration within the kernel drivers as you suggest, but quickly realized that besides the practical problem of kernel upstreaming being a much more arduous road (which can be overcome), the bigger problem was that there is no standardization in the configuration interfaces for the NICs in the kernel community. So different drivers do things differently and expose different settings, and no forum exists to drive towards such standardization. This was leading to vendors have to maintain patched versions of drivers for doing PF configuration, which is not a desirable situation. 

So, to build a portable (to multiple NICs) SRIOV VF manager like VFd, DPDK seemed like a good a forum with some hope for driving towards a standard set of interfaces and without having to worry about a lot of legacy baggage and old hardware. Especially since DPDK already takes on the role of configuring NICs for the data plane functions anyway - both PF and VF drivers will have to be included for data plane usage anyway - we viewed that adding VF config options will not cause any forking, but simply flush out the DPDK drivers and their interfaces to be more complete. These APIs could be optional, so new vendors aren’t obligated to add them. 

Furthermore, allowing VF config using the DPDK PF driver also has the side benefit of allowing a complete SRIOV system (both VF and PF) to be built entirely with DPDK, also making version alignment easier.

We started with Niantic, which already had PF and VF drivers, and things have worked out very well with it. However, we would like VFd to be a multi-NIC vendor agnostic VF management tool, which is why we’ve been asking for making the PF config APIs richer.    

Regards

KJ


> On Jan 10, 2017, at 3:23 PM, Vincent Jardin <vincent.jardin at 6wind.com> wrote:
> 
> Nope. First one needs to assess if DPDK should be intensively used to become a PF knowing Linux can do the jobs. Linux kernel community does not like the forking of Kernel drivers, I tend to agree that we should not keep duplicating options that can be solved with the Linux kernel.
> 
> Best regards,
> Vincent
> 
>