Re: [PATCH 08/10] hugetlb: remove unneeded SetHPageVmemmapOptimized()

From: Muchun Song
Date: Fri Aug 26 2022 - 21:36:07 EST




> On Aug 26, 2022, at 17:24, Miaohe Lin <linmiaohe@xxxxxxxxxx> wrote:
>
> If code reaches here, it's guaranteed that HPageVmemmapOptimized is set
> for the hugetlb page (or VM_BUG_ON_PAGE() will complain about it). It's

Hi Miaohe,

Right.

> unnecessary to set it again.

No, I suppose you didn’t test this patch since it does not work. The
HPageVmemmapOptimized is cleared in the above code of line
(set_page_private(page, 0)). So NAck.

Thanks,
Muchun

>
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> ---
> mm/hugetlb.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 7934188bbed0..b432a00061e3 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -1520,7 +1520,6 @@ static void add_hugetlb_page(struct hstate *h, struct page *page,
>
> set_compound_page_dtor(page, HUGETLB_PAGE_DTOR);
> set_page_private(page, 0);
> - SetHPageVmemmapOptimized(page);
>
> /*
> * This page is about to be managed by the hugetlb allocator and
> --
> 2.23.0
>
>