Re: [PATCH 4/7] mm/mglru: move max_seq read into walk_update_folio

[Kairui Song <ryncsn@gmail.com>]

On Wed, Aug 19, 2026 at 05:18:51PM +0800, Baolin Wang wrote:
> 
> 
> On 8/18/26 1:38 PM, Kairui Song via B4 Relay wrote:
> > From: Kairui Song <kasong@tencent.com>
> > 
> > walk_pte_range(), walk_pmd_range_locked(), and lru_gen_look_around()
> > each read lrugen->max_seq to compute the target generation used by
> > walk_update_folio(), then pass it as a parameter. Move the read into
> > walk_update_folio() itself so the callers no longer need to compute
> > or pass the value.
> > 
> > The max_seq read now happens once per folio update rather than once
> > per walk range, so folios always get promoted to the current youngest
> > generation.
> > 
> > Signed-off-by: Kairui Song <kasong@tencent.com>
> > Reviewed-by: Baoquan He <baoquan.he@linux.dev>
> > ---
> 
> LGTM. One nit below.
> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
> 
> >   mm/vmscan.c | 29 ++++++++++++-----------------
> >   1 file changed, 12 insertions(+), 17 deletions(-)
> > 
> > diff --git a/mm/vmscan.c b/mm/vmscan.c
> > index 080132997d87..a819be6b7ae9 100644
> > --- a/mm/vmscan.c
> > +++ b/mm/vmscan.c
> > @@ -3517,13 +3517,15 @@ static bool suitable_to_scan(int total, int young)
> >   }
> >   static void walk_update_folio(struct lru_gen_mm_walk *walk, struct vm_area_struct *vma,
> > -		struct folio *folio, int new_gen, bool dirty)
> > +			      struct lruvec *lruvec, struct folio *folio, bool dirty)
> 
> IIRC, MM maintainers prefer 2 tabs, which is why I changed this earlier:)

Thanks for the info! I'll keep this line untouched then, my editors auto
indent always align any code I touched to the open bracket that's why this
line is changed :)