On 21.08.23 18:08, David Hildenbrand wrote:
Let's stop using page->private on tail pages, making it possible to
just unconditionally reuse that field in the tail pages of large folios.
The remaining usage of the private field for THP_SWAP is in the THP
splitting code (mm/huge_memory.c), that we'll handle separately later.
Update the THP_SWAP documentation and sanity checks in mm_types.h and
__split_huge_page_tail().
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
---
@Andrew, the following change on top
From 2b1fd10ef07c6d47aa9cd0ce10445ab1e1b97361 Mon Sep 17 00:00:00 2001
From: David Hildenbrand <david@xxxxxxxxxx>
Date: Tue, 22 Aug 2023 19:16:55 +0200
Subject: [PATCH] fixup: mm/swap: stop using page->private on tail pages for
THP_SWAP
Per Yoshry, use folio_page_idx(). It shouldn't make a difference for
our (THP) use case, but it's certainly cleaner.
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
---
include/linux/swap.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 84fe0e94f5cd..e5cf58a1cf9e 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -344,7 +344,7 @@ static inline swp_entry_t page_swap_entry(struct page *page)
struct folio *folio = page_folio(page);
swp_entry_t entry = folio_swap_entry(folio);
- entry.val += page - &folio->page;
+ entry.val += folio_page_idx(folio, page);
return entry;
}
--
2.41.0
--
Cheers,
David / dhildenb
