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

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Message-ID: <d3b6ca06-92d5-4989-9d5a-5a6f93300bcc@redhat.com>
Date: Wed, 2 Jul 2025 11:16:23 +0200
From: David Hildenbrand <david@...hat.com>
To: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org,
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Subject: Re: [PATCH v1 23/29] mm/page-alloc: remove PageMappingFlags()

On 02.07.25 11:09, Lorenzo Stoakes wrote:
> 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... :>)

Heh, I don't think we ever used PAE in the src + git log when talking 
about PageAnonExclusive at least :)

-- 
Cheers,

David / dhildenb