Re: [PATCH v2] mm: skip folio_activate() for mlocked folios

[SeongJae Park <sj@kernel.org>]

On Wed, 8 Oct 2025 11:33:01 +0100 Kiryl Shutsemau <kas@kernel.org> wrote:

> On Tue, Oct 07, 2025 at 12:53:13PM -0700, SeongJae Park wrote:
> > On Mon, 6 Oct 2025 13:25:26 +0000 Dmitry Ilvokhin <d@ilvokhin.com> wrote:
> > 
> > > __mlock_folio() does not move folio to unevicable LRU, when
> > > folio_activate() removes folio from LRU.
> > 
> > A trivial opinion.  So the user-visible issue is the incorrect meminfo, right?
> 
> The user-visible effect is that we unnecessary postpone moving pages to
> unevictable LRU that lead to unexpected stats: Mlocked > Unevictable.

Thank you for clarifying!

> 
> > > ---
> > > Changes in v2:
> > >   - Rephrase commit message: frame it in terms of unevicable LRU, not stat
> > >     accounting.
> > 
> > Yet another trivial and personal opinion.  Adding a link to the previous
> > version could be helpful for reviewers like me.
> 
> You probably missed recent Linus rant on Link: tags :P

I didn't miss it [1] :)  And I pretty sure Linus wouldn't be angry for this,
since what he dislikes is meaningless Link: tags on commit messages.  We are
discussing something about changelog after the '---' line, which will anyway
not added to the commit message.  Also I'm saying a link in a general form, not
specifically Link: tag.

[1] https://lwn.net/Articles/1037069/


Thanks,
SJ

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