linux-kernel - Re: [PATCH v1 23/29] mm/page-alloc: remove PageMappingFlags()

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Message-ID: <f080fd36-8587-42d9-a411-59128bcce195@lucifer.local>
Date: Wed, 2 Jul 2025 10:09:55 +0100
From: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
To: David Hildenbrand <david@...hat.com>
Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        linux-doc@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
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        Shakeel Butt <shakeel.butt@...ux.dev>
Subject: Re: [PATCH v1 23/29] mm/page-alloc: remove PageMappingFlags()

On Wed, Jul 02, 2025 at 11:02:21AM +0200, David Hildenbrand wrote:
> On 02.07.25 10:49, Lorenzo Stoakes wrote:
> > On Tue, Jul 01, 2025 at 09:34:41PM +0200, David Hildenbrand wrote:
> > > On 01.07.25 15:02, Lorenzo Stoakes wrote:
> > > > On Mon, Jun 30, 2025 at 03:00:04PM +0200, David Hildenbrand wrote:
> > > > > We can now simply check for PageAnon() and remove PageMappingFlags().
> > > > >
> > > > > ... and while at it, use the folio instead and operate on
> > > > > folio->mapping.
> > > >
> > > > Probably worth mentioning to be super crystal clear that this is because
> > > > now it's either an anon folio or a KSM folio, both of which set the
> > > > FOLIO_MAPPING_ANON flag.
> > >
> > > "As PageMappingFlags() now only indicates anon (incl. ksm) folios, we can
> > > now simply check for PageAnon() and remove PageMappingFlags()."
> >
> > Sounds good! Though the extremely nitty part of me says 'capitalise KSM' :P
>
> Like we do so consistently with vma, pte and all the other acronyms ;)

Don't forget pae which now means something different depending on whether you're
talking about x86-64 page tables or anon exclusive flags... :>)

Yeah, I mean it's throwing teaspoons of water out of a reservoir but might as
well :P

>
> Can do!
>
> --
> Cheers,
>
> David / dhildenb
>