Re: [PATCHv3, RESEND 6/8] khugepaged: Allow to collapse PTE-mapped compound pages

[Kirill A. Shutemov]

On Wed, Apr 15, 2020 at 02:44:26PM -0700, Andrew Morton wrote:
> On Mon, 13 Apr 2020 15:52:18 +0300 "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> wrote:
> 
> > We can collapse PTE-mapped compound pages. We only need to avoid
> > handling them more than once: lock/unlock page only once if it's present
> > in the PMD range multiple times as it handled on compound level. The
> > same goes for LRU isolation and putback.
> > 
> > ...
> >
> > --- a/mm/khugepaged.c
> > +++ b/mm/khugepaged.c
> > @@ -515,17 +515,30 @@ void __khugepaged_exit(struct mm_struct *mm)
> >  
> >  static void release_pte_page(struct page *page)
> >  {
> > -	dec_node_page_state(page, NR_ISOLATED_ANON + page_is_file_cache(page));
> 
> I have
> 
> 	dec_node_page_state(page, NR_ISOLATED_ANON + page_is_file_lru(page));
> 
> here.  Is there some prerequisite which I wasn't able to find?

The patchset is on top of v5.6. It has been changed since. See
9de4f22a60f7 ("mm: code cleanup for MADV_FREE").

Look like a trivial fixup is required.

-- 
 Kirill A. Shutemov