Re: [RFC 00/19] Split netmem from struct page

[Byungchul Park <byungchul@sk.com>]

On Fri, May 09, 2025 at 07:09:16AM -0700, Mina Almasry wrote:
> On Fri, May 9, 2025 at 4:51 AM Byungchul Park <byungchul@sk.com> wrote:
> >
> > The MM subsystem is trying to reduce struct page to a single pointer.
> > The first step towards that is splitting struct page by its individual
> > users, as has already been done with folio and slab.  This patchset does
> > that for netmem which is used for page pools.
> >
> > Matthew Wilcox tried and stopped the same work, you can see in:
> >
> >    https://lore.kernel.org/linux-mm/20230111042214.907030-1-willy@infradead.org/
> >
> > Mina Almasry already has done a lot fo prerequisite works by luck, he
> > said :).  I stacked my patches on the top of his work e.i. netmem.
> >
> > I focused on removing the page pool members in struct page this time,
> > not moving the allocation code of page pool from net to mm.  It can be
> > done later if needed.
> >
> > There are still a lot of works to do, to remove the dependency on struct
> > page in the network subsystem.  I will continue to work on this after
> > this base patchset is merged.
> >
> > This patchset is based on mm tree's mm-unstable branch.
> >
> 
> This series largely looks good to me, but a couple of things:
> 
> - For deep changes like this to the page_pool, I think we need a
> before/after run to Jesper's currently out-of-tree benchmark to see
> any regressions:
> https://lore.kernel.org/netdev/20250309084118.3080950-1-almasrymina@google.com/

Sure.  I will check it.

> - Also please CC Pavel on iterations related to netmem/net_iov, they
> are reusing that in io_uring code for iouring rx rc as well.

I will.  Thank you.

	Byungchul

> --
> Thanks,
> Mina