Re: [PATCH bpf-next v3 1/3] xsk: Support UMEM chunk_size > PAGE_SIZE

From: Maciej Fijalkowski
Date: Fri Apr 07 2023 - 12:28:39 EST


On Thu, Apr 06, 2023 at 08:38:05PM +0200, Toke Høiland-Jørgensen wrote:
> Kal Conley <kal.conley@xxxxxxxxxxx> writes:
>
> > Add core AF_XDP support for chunk sizes larger than PAGE_SIZE. This
> > enables sending/receiving jumbo ethernet frames up to the theoretical
> > maxiumum of 64 KiB. For chunk sizes > PAGE_SIZE, the UMEM is required
> > to consist of HugeTLB VMAs (and be hugepage aligned). Initially, only
> > SKB mode is usable pending future driver work.
>
> Hmm, interesting. So how does this interact with XDP multibuf?

To me it currently does not interact with mbuf in any way as it is enabled
only for skb mode which linearizes the skb from what i see.

I'd like to hear more about Kal's use case - Kal do you use AF_XDP in SKB
mode on your side?

>
> -Toke
>