Re: [PATCH 1/6] mm: ksm: use more folio api in ksm_might_need_to_copy()

[Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>]

On 2023/11/7 22:24, Matthew Wilcox wrote:
> On Tue, Nov 07, 2023 at 09:52:11PM +0800, Kefeng Wang wrote:
> >   struct page *ksm_might_need_to_copy(struct page *page,
> > -			struct vm_area_struct *vma, unsigned long address)
> > +			struct vm_area_struct *vma, unsigned long addr)
> >   {
> >   	struct folio *folio = page_folio(page);
> >   	struct anon_vma *anon_vma = folio_anon_vma(folio);
> > -	struct page *new_page;
> > +	struct folio *new_folio;
> >   
> > -	if (PageKsm(page)) {
> > -		if (page_stable_node(page) &&
> > +	if (folio_test_ksm(folio)) {
> > +		if (folio_stable_node(folio) &&
> >   		    !(ksm_run & KSM_RUN_UNMERGE))
> >   			return page;	/* no need to copy it */
> >   	} else if (!anon_vma) {
> >   		return page;		/* no need to copy it */
> > -	} else if (page->index == linear_page_index(vma, address) &&
> > +	} else if (page->index == linear_page_index(vma, addr) &&
>
> Hmm.  page->index is going away.  What should we do here instead?

Do you mean to replace page->index to folio->index, or kill index from
struct page?

> The rest of this looks good.