Re: [PATCH 1/2] mm: mmap: no need to call khugepaged_enter_vma() for stack

From: Huang, Ying
Date: Mon Jan 15 2024 - 00:52:39 EST


Yang Shi <shy828301@xxxxxxxxx> writes:

> From: Yang Shi <yang@xxxxxxxxxxxxxxxxxxxxxx>
>
> We avoid allocating THP for temporary stack, even tnough
~~~~~~
though?

--
Best Regards,
Huang, Ying

> khugepaged_enter_vma() is called for stack VMAs, it actualy returns
> false. So no need to call it in the first place at all.
>
> Signed-off-by: Yang Shi <yang@xxxxxxxxxxxxxxxxxxxxxx>
> ---
> mm/mmap.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index b78e83d351d2..2ff79b1d1564 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -2046,7 +2046,6 @@ static int expand_upwards(struct vm_area_struct *vma, unsigned long address)
> }
> }
> anon_vma_unlock_write(vma->anon_vma);
> - khugepaged_enter_vma(vma, vma->vm_flags);
> mas_destroy(&mas);
> validate_mm(mm);
> return error;
> @@ -2140,7 +2139,6 @@ int expand_downwards(struct vm_area_struct *vma, unsigned long address)
> }
> }
> anon_vma_unlock_write(vma->anon_vma);
> - khugepaged_enter_vma(vma, vma->vm_flags);
> mas_destroy(&mas);
> validate_mm(mm);
> return error;