Re: [PATCH mm-unstable v19 12/14] mm/khugepaged: avoid unnecessary mTHP collapse attempts

[Lorenzo Stoakes]

On Fri, Jun 05, 2026 at 07:49:34PM +0200, David Hildenbrand (Arm) wrote:
> On 6/5/26 18:14, Nico Pache wrote:
> > There are cases where, if an attempted collapse fails, all subsequent
> > orders are guaranteed to also fail. Avoid these collapse attempts by
> > bailing out early.
> >
> > Reviewed-by: Lorenzo Stoakes <ljs@xxxxxxxxxx>
> > Acked-by: Usama Arif <usama.arif@xxxxxxxxx>
> > Acked-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>
> > Signed-off-by: Nico Pache <npache@xxxxxxxxxx>
> > ---
> >  mm/khugepaged.c | 13 +++++++++++++
> >  1 file changed, 13 insertions(+)
> >
> > diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> > index 430047316f43..7de92b28dd30 100644
> > --- a/mm/khugepaged.c
> > +++ b/mm/khugepaged.c
> > @@ -1499,6 +1499,7 @@ static enum scan_result mthp_collapse(struct mm_struct *mm,
> >  			collapse_address = address + offset * PAGE_SIZE;
> >  			ret = collapse_huge_page(mm, collapse_address, referenced,
> >  						 unmapped, cc, order);
> > +
>
> Unrelated to this patch, but not the end of the world :)

NA....h that's fine ;)

>
> --
> Cheers,
>
> David

Cheers, Lorenzo