Message-ID: <bd162903-6854-4b69-ad4b-89deb8e0d695@redhat.com>
Date: Wed, 2 Jul 2025 16:52:53 +0200
From: David Hildenbrand <david@...hat.com>
To: Harry Yoo <harry.yoo@...cle.com>
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Subject: Re: [PATCH v1 27/29] docs/mm: convert from "Non-LRU page migration"
 to "movable_ops page migration"

On 02.07.25 16:23, Harry Yoo wrote:
> On Mon, Jun 30, 2025 at 03:00:08PM +0200, David Hildenbrand wrote:
>> Let's bring the docs up-to-date.
>>
>> Reviewed-by: Zi Yan <ziy@...dia.com>
>> Signed-off-by: David Hildenbrand <david@...hat.com>
>> ---
>>
>> +movable_ops page migration
>> +==========================
>> +
>> +Selected typed, non-folio pages (e.g., pages inflated in a memory balloon,
>> +zsmalloc pages) can be migrated using the movable_ops migration framework.
>> +
>> +The "struct movable_operations" provide callbacks specific to a page type
>> +for isolating, migrating and un-isolating (putback) these pages.
>> +
>> +Once a page is indicated as having movable_ops, that condition must not
>> +change until the page was freed back to the buddy. This includes not
>> +changing/clearing the page type and not changing/clearing the
>> +PG_movable_ops page flag.
>> +
>> +Arbitrary drivers cannot currently make use of this framework, as it
>> +requires:
>> +
>> +(a) a page type
>> +(b) indicating them as possibly having movable_ops in page_has_movable_ops()
>> +    based on the page type
> 
>> +(c) returning the movable_ops from page_has_movable_ops() based on the page
>> +    type
> 
> I think you meant page_movable_ops()?

Very right, thanks!

-- 
Cheers,

David / dhildenb

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