Re: [PATCH v4 3/4] mm: Support batched unmap for lazyfree large folios during reclamation

[David Hildenbrand]

On 26.06.25 23:46, Barry Song wrote:
> On Thu, Jun 26, 2025 at 9:29 PM Lance Yang <ioworker0@xxxxxxxxx> wrote:
> >
> [...]
> > +
> > +               /*
> > +                * If we are sure that we batched the entire folio and cleared
> > +                * all PTEs, we can just optimize and stop right here.
> > +                */
> > +               if (nr_pages == folio_nr_pages(folio))
>
> David also mentioned if (nr_pages > 1 && nr_pages == folio_nr_pages(folio)).
> I assume it’s still fine when nr_pages == 1 for small folios? No?

Yeah, as raised I think it is fine. We should never have any folio page 
mapped multiple times into the same VMA in any case. (excluding KSM 
pages, but they are handled differenty, using a specialized rmap walk)

--
Cheers,

David / dhildenb