On Mon, Dec 17, 2018 at 04:30:05PM +0100, Björn Töpel wrote: > > > > Instead of introducing the XDP_ATTACH option to the bind call, can we > > just make this association between rx queue id and xsk every single > > time we bind? Then it is up to the user via the XDP program if he/she > > wants to use this by calling xsk_redirect. No new option needed. > > > > Nice! Then it would simply be a matter of adding the helper. Much better > than extending the uapi. Thank you for pointing this out!
Magnus's by-default association approach sounds good to me. I'm missing though why extra bpf helper is needed. This soft-bind rx queue with xsk at the time of normal bind() should work as-is and no program necessary. No prog -> default assoc. Yet the prog has an ability to redirect to specific xsk via existing bpf_redirect_map or via faster (future) xsk_redirect. Also I agree with Jesper that per-queue programs would be good to have sooner than later, but I disagree that it's mandatory for this set. It seems the patches will give us performance boost and simplification of uapi while per-queue prog api is being discussed and implemented. I like the other idea too (of having libbpf provide canned bpf progs for different use cases). That's better than loading them from the kernel.
