configuring RSS offloads with Netvsc PMD

[Stephen Hemminger]

On Wed, 28 Aug 2024 10:32:17 -0700
Nandini Rangaswamy <nandini.rangaswamy at broadcom.com> wrote:

> Hi Long and Stephen,
> I am trying to configure RSS offloads from my DPDK App with netvsc PMD.
> Netvsc seems to be supporting the following offloads:
> RTE_ETH_RSS_NONFRAG_IPV4_UDP RTE_ETH_RSS_NONFRAG_IPV4_TCP
> RTE_ETH_RSS_NONFRAG_IPV6_TCP RTE_ETH_RSS_IPV4
> RTE_ETH_RSS_IPV6
> 
> However, the app is trying to configure the following offloads and failing:
> 
> RTE_ETH_RSS_NONFRAG_IPV4_UDP
> RTE_ETH_RSS_NONFRAG_IPV4_TCP
> RTE_ETH_RSS_NONFRAG_IPV6_TCP
> RTE_ETH_RSS_NONFRAG_IPV6_UDP

Confusing, both of these overlap should work.
Please instrument the configure code in netvsc to see why it is complaining.

> 
> Is it possible to bypass the netvsc PMD and configure these offloads on VF
> ? I am aware that app should not directly program the VF interface
> but for performance sake, I want the above offloads to be supported on VF.

No can't bypass driver.

You do need to configure multiqueue and enable RSS in configure
to get anything.

If you look at hn_rss_hash_init, the driver needs to convert the
requested flags into NDIS flags to tell the host what to do.