Re: [PATCH v2 2/5] mm/thp: fix node page state in split_huge_page_to_list()

[Yang Shi]

On Thu, Oct 17, 2019 at 9:42 AM Song Liu <songliubraving@xxxxxx> wrote:
>
> From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
>
> Make sure split_huge_page_to_list() handle the state of shmem THP and
> file THP properly.
>
> Fixes: 60fbf0ab5da1 ("mm,thp: stats for file backed THP")
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> Tested-by: Song Liu <songliubraving@xxxxxx>
> Signed-off-by: Song Liu <songliubraving@xxxxxx>

Acked-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>

> ---
>  mm/huge_memory.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index c5cb6dcd6c69..13cc93785006 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -2789,8 +2789,13 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
>                         ds_queue->split_queue_len--;
>                         list_del(page_deferred_list(head));
>                 }
> -               if (mapping)
> -                       __dec_node_page_state(page, NR_SHMEM_THPS);
> +               if (mapping) {
> +                       if (PageSwapBacked(page))
> +                               __dec_node_page_state(page, NR_SHMEM_THPS);
> +                       else
> +                               __dec_node_page_state(page, NR_FILE_THPS);
> +               }
> +
>                 spin_unlock(&ds_queue->split_queue_lock);
>                 __split_huge_page(page, list, end, flags);
>                 if (PageSwapCache(head)) {
> --
> 2.17.1
>
>