Re: [Patch v2 1/3] mm/khugepaged: remove redundant clearing of struct collapse_control

[Nico Pache <npache@redhat.com>]

On Thu, Nov 13, 2025 at 8:01 PM Wei Yang <richard.weiyang@gmail.com> wrote:
>
> The structure struct collapse_control is being unnecessarily cleared
> twice during the huge page collapse process.
>
> Both hpage_collapse_scan_file() and hpage_collapse_scan_pmd() currently
> perform a clear operation on this structure.
>
> Remove the redundant clear operation.

Nice! The more we can simplify/unify madvise_collapse/collapse the better :)

LGTM!

Reviewed-by: Nico Pache <npache@redhat.com>

>
> Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
> ---
>  mm/khugepaged.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 7e8cb181d5bd..1fc8986a28b3 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -2803,8 +2803,6 @@ int madvise_collapse(struct vm_area_struct *vma, unsigned long start,
>                         hend = min(hend, vma->vm_end & HPAGE_PMD_MASK);
>                 }
>                 mmap_assert_locked(mm);
> -               memset(cc->node_load, 0, sizeof(cc->node_load));
> -               nodes_clear(cc->alloc_nmask);
>                 if (!vma_is_anonymous(vma)) {
>                         struct file *file = get_file(vma->vm_file);
>                         pgoff_t pgoff = linear_page_index(vma, addr);
> --
> 2.34.1
>