Re: [PATCH rfc 00/12] mm: BPF OOM

[Song Liu]

On Mon, Apr 28, 2025 at 6:57 PM Kumar Kartikeya Dwivedi
<memxor@xxxxxxxxx> wrote:
[...]
> >
> > It's certainly an option and I thought about it. I don't think we need a bunch
> > of hooks though. This patchset adds 2 and they belong to completely different
> > subsystems (mm and sched/psi), so Idk how well they can be gathered
> > into a single struct ops. But maybe it's fine.
> >
> > The only potentially new hook I can envision now is one to customize
> > the oom reporting.
> >
>
> If you're considering scoping it down to a particular cgroup (as you
> allude to in the TODO), or building a hierarchical interface, using
> struct_ops will be much better than fmod_ret etc., which is global in
> nature. Even if you don't support it now. I don't think a struct_ops
> is warranted only when you have more than a few callbacks. As an
> illustration, sched_ext started out without supporting hierarchical
> attachment, but will piggy-back on the struct_ops interface to do so
> in the near future.

+1 for using struct_ops, which is the best way to enable BPF in
existing use cases.

Song