Re: [PATCH] mm/huge_memory: remove unneeded local variable follflags

From: Anshuman Khandual
Date: Thu Mar 10 2022 - 23:51:41 EST


Hi Miaohe,

On 3/10/22 18:42, Miaohe Lin wrote:
> We can pass FOLL_GET | FOLL_DUMP to follow_page directly to simplify
> the code a bit.
>
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> ---
> mm/huge_memory.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 3557aabe86fe..418d077da246 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -2838,7 +2838,6 @@ static int split_huge_pages_pid(int pid, unsigned long vaddr_start,
> */
> for (addr = vaddr_start; addr < vaddr_end; addr += PAGE_SIZE) {
> struct vm_area_struct *vma = find_vma(mm, addr);
> - unsigned int follflags;
> struct page *page;
>
> if (!vma || addr < vma->vm_start)
> @@ -2851,8 +2850,7 @@ static int split_huge_pages_pid(int pid, unsigned long vaddr_start,
> }
>
> /* FOLL_DUMP to ignore special (like zero) pages */
> - follflags = FOLL_GET | FOLL_DUMP;
> - page = follow_page(vma, addr, follflags);
> + page = follow_page(vma, addr, FOLL_GET | FOLL_DUMP);
>
> if (IS_ERR(page))
> continue;

LGTM, but there is another similar instance in add_page_for_migration()
inside mm/migrate.c, requiring this exact clean up.

Hence with that change in place.

Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>