Re: PF_PACKET RPS like using bpf

[Stanislav Fomichev <sdf@google.com>]

On 03/14, Alexandre Cassen wrote:
> Hello,
> 
> While implementing a large scale L2 processing soft, there is a need for
> high perf ingress handling.
> 
> In short: using BPF socket_filter prog with a hash func over ethernet
> address to distribute load across multiple PF_PACKET sockets: mainly
> filtering out non related hkey packets. It simplify userland app by using
> multiple PF_PACKET sockets in dedicated pthread.
> 
> Longer discussion + quick source code illustration here:
> 
> https://github.com/acassen/bpf-pfpacket-rps
> 
> 
> My question would be related to sockmap. I tried to figure out how to
> perform the same policing design using sockmap. And cant find my way around
> it :/ If bpf verdict prog can get socket fd from __sk_buff then it could
> drives the same hash/policing decision.
> 
> Is it possible to get socket fd from __sk_buff from sockmap verdict prog ?

Don't have an answer about sockmap, but I'd suggest you look at AF_XDP
if you want the best perf out there with raw frames.
IIRC, it just recently got a mode where you can redirect into multiple
sockets (== consumer threads):

https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=2863d665ea41