Re: [PATCH v2 bpf 2/3] module: introduce module_alloc_huge

From: Song Liu
Date: Tue Apr 12 2022 - 02:12:15 EST


On Mon, Apr 11, 2022 at 9:20 PM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote:
>
> On Mon, Apr 11, 2022 at 04:35:47PM -0700, Song Liu wrote:
> > Introduce module_alloc_huge, which allocates huge page backed memory in
> > module memory space. The primary user of this memory is bpf_prog_pack
> > (multiple BPF programs sharing a huge page).
>
> I kow I lead you downthis road first, but I wonder if we just want to
> pass a flag to module_alloc instead. This avoids duplicating all the
> arch overrides.

I don't think we will see many archs support bpf_prog_pack, so the __weak
version might be good enough for a long time. Adding an argument to
module_alloc seems like more trouble to me.

Thanks,
Song