[PATCH v2 6/6] mm/hugetlb: use folio->lru int demote_free_hugetlb_folios()

David Hildenbrand
2025-01-13T13:17:02Z

We are demoting hugetlb folios to smaller hugetlb folios; let's avoid
messing with pages where avoidable and handle it more similar to
__split_huge_page_tail().

Signed-off-by: David Hildenbrand <david@redhat.com>
---
mm/hugetlb.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index bc4ab45d9b93b..a94d52dd53728 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3822,13 +3822,15 @@ static long demote_free_hugetlb_folios(struct hstate *src, struct hstate *dst,

for (i = 0; i < pages_per_huge_page(src); i += pages_per_huge_page(dst)) {
struct page *page = folio_page(folio, i);
+ /* Careful: see __split_huge_page_tail() */
+ struct folio *new_folio = (struct folio *)page;

- page->mapping = NULL;
clear_compound_head(page);
prep_compound_page(page, dst->order);

- init_new_hugetlb_folio(dst, page_folio(page));
- list_add(&page->lru, &dst_list);
+ new_folio->mapping = NULL;
+ init_new_hugetlb_folio(dst, new_folio);
+ list_add(&new_folio->lru, &dst_list);
}
}

--
2.47.1