diff options
Diffstat (limited to 'mm')
-rw-r--r-- | mm/page_alloc.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 96d48d24e1ef..5afdf495c374 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -705,16 +705,14 @@ static inline void rmv_page_order(struct page *page) /* * This function checks whether a page is free && is the buddy - * we can do coalesce a page and its buddy if + * we can coalesce a page and its buddy if * (a) the buddy is not in a hole (check before calling!) && * (b) the buddy is in the buddy system && * (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 set ->_mapcount - * PAGE_BUDDY_MAPCOUNT_VALUE. - * Setting, clearing, and testing _mapcount PAGE_BUDDY_MAPCOUNT_VALUE is - * serialized by zone->lock. + * For recording whether a page is in the buddy system, we set PageBuddy. + * Setting, clearing, and testing PageBuddy is serialized by zone->lock. * * For recording page's order, we use page_private(page). */ @@ -759,9 +757,8 @@ static inline int page_is_buddy(struct page *page, struct page *buddy, * as necessary, plus some accounting needed to play nicely with other * parts of the VM system. * At each level, we keep a list of pages, which are heads of continuous - * free pages of length of (1 << order) and marked with _mapcount - * PAGE_BUDDY_MAPCOUNT_VALUE. Page's order is recorded in page_private(page) - * field. + * free pages of length of (1 << order) and marked with PageBuddy. + * Page's order is recorded in page_private(page) field. * So when we are allocating or freeing one, we can derive the state of the * other. That is, if we allocate a small block, and both were * free, the remainder of the region must be split into blocks. |