Re: [PATCH 3/5] hugetlb_cgroup: remove unnecessary VM_BUG_ON_PAGE in hugetlb_cgroup_migrate()

[Mike Kravetz]

On 3/8/21 3:28 AM, Miaohe Lin wrote:
> !PageHuge(oldhpage) is implicitly checked in page_hstate() above, so we
> remove this explicit one.

Correct.  In addition, this will only be called for hugetlb pages.  The
VM_BUG_ON_PAGE is unnecessary.

> 
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> ---
>  mm/hugetlb_cgroup.c | 1 -
>  1 file changed, 1 deletion(-)

Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
-- 
Mike Kravetz

> 
> diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c
> index 8668ba87cfe4..3dde6ddf0170 100644
> --- a/mm/hugetlb_cgroup.c
> +++ b/mm/hugetlb_cgroup.c
> @@ -785,7 +785,6 @@ void hugetlb_cgroup_migrate(struct page *oldhpage, struct page *newhpage)
>  	if (hugetlb_cgroup_disabled())
>  		return;
>  
> -	VM_BUG_ON_PAGE(!PageHuge(oldhpage), oldhpage);
>  	spin_lock(&hugetlb_lock);
>  	h_cg = hugetlb_cgroup_from_page(oldhpage);
>  	h_cg_rsvd = hugetlb_cgroup_from_page_rsvd(oldhpage);
>