On 2023/11/8 21:59, Matthew Wilcox wrote:
On Wed, Nov 08, 2023 at 09:40:09AM +0800, Kefeng Wang wrote:
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?
I'm asking you what we should do.
Tail pages already don't have a valid ->index (or ->mapping).
So presumably we can't see a tail page here today. But will we in future?
I think we could replace page->index to page_to_pgoff(page).
Just to remind you, the goal here is:
struct page {
unsigned long memdesc;
};
Get your point, that will be great.
so folios will be the only thing that have a ->index. I haven't looked
at this code; I know nothing about it. But you're changing it, so you
must have some understanding of it.
