diff options
Diffstat (limited to 'mm/page_alloc.c')
-rw-r--r-- | mm/page_alloc.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a2955e101715..da526905b4a5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -509,16 +509,26 @@ static inline int page_is_buddy(struct page *page, struct page *buddy, if (!pfn_valid_within(page_to_pfn(buddy))) return 0; - if (page_zone_id(page) != page_zone_id(buddy)) - return 0; - if (page_is_guard(buddy) && page_order(buddy) == order) { VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); + + if (page_zone_id(page) != page_zone_id(buddy)) + return 0; + return 1; } if (PageBuddy(buddy) && page_order(buddy) == order) { VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); + + /* + * zone check is done late to avoid uselessly + * calculating zone/node ids for pages that could + * never merge. + */ + if (page_zone_id(page) != page_zone_id(buddy)) + return 0; + return 1; } return 0; |