Re: [PATCH 1/2] mm/huge_memory: introduce __split_folio_and_update_stats() to consolidate split task

[Wei Yang <richard.weiyang@gmail.com>]

On Mon, Nov 03, 2025 at 05:22:10PM +0100, David Hildenbrand (Red Hat) wrote:
>On 03.11.25 17:21, David Hildenbrand (Red Hat) wrote:
>> On 03.11.25 17:20, David Hildenbrand (Red Hat) wrote:
>> > On 01.11.25 01:29, Wei Yang wrote:
>> > > The folio splitting process involves several related tasks that are
>> > > executed together:
>> > > 
>> > >        Adjusting memcg (memory control group) accounting.
>> > >        Updating page owner tracking.
>> > >        Splitting the folio to the target size (new_order).
>> > >        Updating necessary folio statistics.
>> > > 
>> > > This commit introduces the new helper function,
>> > > __split_folio_and_update_stats(), to gather all these tasks. This
>> > > consolidation improves modularity and is a necessary preparation step
>> > > for further cleanup and simplification of the surrounding folio
>> > > splitting logic.
>> > > 
>> > > Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
>> > > Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
>> > > Cc: Zi Yan <ziy@nvidia.com>
>> > > ---
>> > >     mm/huge_memory.c | 28 +++++++++++++++++-----------
>> > >     1 file changed, 17 insertions(+), 11 deletions(-)
>> > > 
>> > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>> > > index c37fe6ad0c96..abde0f1aa8ff 100644
>> > > --- a/mm/huge_memory.c
>> > > +++ b/mm/huge_memory.c
>> > > @@ -3567,6 +3567,22 @@ static void __split_folio_to_order(struct folio *folio, int old_order,
>> > >     		ClearPageCompound(&folio->page);
>> > >     }
>> > > +static void __split_folio_and_update_stats(struct folio *folio, int old_order,
>> > > +		int new_order, bool is_anon)
>> > 
>> > Is there any good reason we want to pass things like "is_anon" instead
>> > of just querying it in that helper?
>> > 
>> > 
>> > > +{
>> > > +	int nr_new_folios = 1UL << (old_order - new_order);
>> > 
>> > Could be const.
>> > 
>> > 
>> 
>> Looking at it again, and that we are not reusing this function on patch
>> #2, I am not sure factoring this out is really helpful at this point?
>
>Ignore that, I was briefly confused by patch #2 :)
>

Hi, David

Would you mind be more specific on which part confuse you?

>-- 
>Cheers
>
>David

-- 
Wei Yang
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