Re: [PATCHv3, RESEND 8/8] khugepaged: Introduce 'max_ptes_shared' tunable

[Kirill A. Shutemov]

On Wed, Apr 15, 2020 at 02:25:30PM -0700, Yang Shi wrote:
> > @@ -595,6 +626,12 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> >   		VM_BUG_ON_PAGE(!PageAnon(page), page);
> > +		if (page_mapcount(page) > 1 &&
> > +				++shared > khugepaged_max_ptes_shared) {
> > +			result = SCAN_EXCEED_SHARED_PTE;
> 
> It may be better to extract the check into a helper? For example, bool
> exceed_max_ptes_shared(struct page)?

It might be reasonable as part of wider cleanup: the same has to be done
to khugepaged_max_ptes_none and khugepaged_max_ptes_swap.

Volunteers? :P

-- 
 Kirill A. Shutemov