From 310183de7bb2ed114a80d057690ddb23d0cfe814 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 9 Aug 2024 14:48:50 +0300 Subject: [PATCH] mm: introduce PageUnaccepted() page type The new page type allows physical memory scanners to detect unaccepted memory and handle it accordingly. The page type is serialized with zone lock. Link: https://lkml.kernel.org/r/20240809114854.3745464-5-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Acked-by: David Hildenbrand Cc: Borislav Petkov Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Mel Gorman Cc: Mike Rapoport (Microsoft) Cc: Tom Lendacky Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/page-flags.h | 8 ++++++++ mm/page_alloc.c | 2 ++ 2 files changed, 10 insertions(+) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index a0a29bd092f8..17175a328e6b 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -939,6 +939,7 @@ enum pagetype { PG_hugetlb = 0x04000000, PG_slab = 0x02000000, PG_zsmalloc = 0x01000000, + PG_unaccepted = 0x00800000, PAGE_TYPE_BASE = 0x80000000, @@ -1072,6 +1073,13 @@ FOLIO_TEST_FLAG_FALSE(hugetlb) PAGE_TYPE_OPS(Zsmalloc, zsmalloc, zsmalloc) +/* + * Mark pages that has to be accepted before touched for the first time. + * + * Serialized with zone lock. + */ +PAGE_TYPE_OPS(Unaccepted, unaccepted, unaccepted) + /** * PageHuge - Determine if the page belongs to hugetlbfs * @page: The page to test. diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 9dde1b04a04e..fec7ed5a04f2 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6963,6 +6963,7 @@ static bool try_to_accept_memory_one(struct zone *zone) account_freepages(zone, -MAX_ORDER_NR_PAGES, MIGRATE_MOVABLE); __mod_zone_page_state(zone, NR_UNACCEPTED, -MAX_ORDER_NR_PAGES); + __ClearPageUnaccepted(page); spin_unlock_irqrestore(&zone->lock, flags); accept_page(page, MAX_PAGE_ORDER); @@ -7021,6 +7022,7 @@ static bool __free_unaccepted(struct page *page) list_add_tail(&page->lru, &zone->unaccepted_pages); account_freepages(zone, MAX_ORDER_NR_PAGES, MIGRATE_MOVABLE); __mod_zone_page_state(zone, NR_UNACCEPTED, MAX_ORDER_NR_PAGES); + __SetPageUnaccepted(page); spin_unlock_irqrestore(&zone->lock, flags); if (first)