diff --git a/include/linux/mm.h b/include/linux/mm.h index e2fa375e478e..697c6bf248c2 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -465,10 +465,13 @@ static inline unsigned long page_zonenum(struct page *page) struct zone; extern struct zone *zone_table[]; +static inline int page_zone_id(struct page *page) +{ + return (page->flags >> ZONETABLE_PGSHIFT) & ZONETABLE_MASK; +} static inline struct zone *page_zone(struct page *page) { - return zone_table[(page->flags >> ZONETABLE_PGSHIFT) & - ZONETABLE_MASK]; + return zone_table[page_zone_id(page)]; } static inline unsigned long page_to_nid(struct page *page) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 253a450c400d..fd631c2536a5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -286,22 +286,27 @@ __find_combined_index(unsigned long page_idx, unsigned int order) * we can do coalesce a page and its buddy if * (a) the buddy is not in a hole && * (b) the buddy is in the buddy system && - * (c) a page and its buddy have the same order. + * (c) a page and its buddy have the same order && + * (d) a page and its buddy are in the same zone. * * For recording whether a page is in the buddy system, we use PG_buddy. * Setting, clearing, and testing PG_buddy is serialized by zone->lock. * * For recording page's order, we use page_private(page). */ -static inline int page_is_buddy(struct page *page, int order) +static inline int page_is_buddy(struct page *page, struct page *buddy, + int order) { #ifdef CONFIG_HOLES_IN_ZONE - if (!pfn_valid(page_to_pfn(page))) + if (!pfn_valid(page_to_pfn(buddy))) return 0; #endif - if (PageBuddy(page) && page_order(page) == order) { - BUG_ON(page_count(page) != 0); + if (page_zone_id(page) != page_zone_id(buddy)) + return 0; + + if (PageBuddy(buddy) && page_order(buddy) == order) { + BUG_ON(page_count(buddy) != 0); return 1; } return 0; @@ -352,7 +357,7 @@ static inline void __free_one_page(struct page *page, struct page *buddy; buddy = __page_find_buddy(page, page_idx, order); - if (!page_is_buddy(buddy, order)) + if (!page_is_buddy(page, buddy, order)) break; /* Move the buddy up one level. */ list_del(&buddy->lru);