From 752fe17af693323dba5622b19c858a46fed219a1 Mon Sep 17 00:00:00 2001 From: Frank van der Linden Date: Fri, 28 Feb 2025 18:29:18 +0000 Subject: mm/hugetlb: add pre-HVO framework Define flags for pre-HVOed bootmem hugetlb pages, and act on them. The most important flag is the HVO flag, signalling that a bootmem allocated gigantic page has already been HVO-ed. If this flag is seen by the hugetlb bootmem gather code, the page is marked as HVO optimized. The HVO code will then not try to optimize it again. Instead, it will just map the tail page mirror pages read-only, completing the HVO steps. No functional change, as nothing sets the flags yet. Link: https://lkml.kernel.org/r/20250228182928.2645936-18-fvdl@google.com Signed-off-by: Frank van der Linden Cc: Alexander Gordeev Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Dan Carpenter Cc: Dave Hansen Cc: David Hildenbrand Cc: Heiko Carstens Cc: Joao Martins Cc: Johannes Weiner Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Muchun Song Cc: Oscar Salvador Cc: Peter Zijlstra Cc: Roman Gushchin (Cruise) Cc: Usama Arif Cc: Vasily Gorbik Cc: Yu Zhao Cc: Zi Yan Signed-off-by: Andrew Morton --- include/linux/hugetlb.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux/hugetlb.h') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index f0ab4ca4ecf2..bbccc3e6b9dd 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -681,8 +681,12 @@ struct hstate { struct huge_bootmem_page { struct list_head list; struct hstate *hstate; + unsigned long flags; }; +#define HUGE_BOOTMEM_HVO 0x0001 +#define HUGE_BOOTMEM_ZONES_VALID 0x0002 + int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list); int replace_free_hugepage_folios(unsigned long start_pfn, unsigned long end_pfn); void wait_for_freed_hugetlb_folios(void); -- cgit v1.2.3