Re: [RFC 03/11] mm: remove SWAP_DIRTY in ttu

[Hillf Danton]

On March 02, 2017 2:39 PM Minchan Kim wrote: 
> @@ -1424,7 +1424,8 @@ static int try_to_unmap_one(struct page *page, struct 
> vm_area_struct *vma,
>                       } else if (!PageSwapBacked(page)) {
>                               /* dirty MADV_FREE page */

Nit: enrich the comment please.
>                               set_pte_at(mm, address, pvmw.pte, pteval);
> -                             ret = SWAP_DIRTY;
> +                             SetPageSwapBacked(page);
> +                             ret = SWAP_FAIL;
>                               page_vma_mapped_walk_done(&pvmw);
>                               break;
>                       }