path: root/mm/internal.h
diff options
authorMel Gorman <mel@csn.ul.ie>2007-10-16 01:26:10 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-16 09:43:01 -0700
commit48f13bf3e742fca8aab87f6c39451d03bf5952d4 (patch)
tree668160019ab157500a90655cf44f798ed3c77893 /mm/internal.h
parentea3061d227816d00717446ac12b853d7ae04b4fe (diff)
Breakout page_order() to internal.h to avoid special knowledge of the buddy allocator
The statistics patch later needs to know what order a free page is on the free lists. Rather than having special knowledge of page_private() when PageBuddy() is set, this patch places out page_order() in internal.h and adds a VM_BUG_ON to catch using it on non-PageBuddy pages. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Christoph Lameter <clameter@sgi.com> Acked-by: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/internal.h')
1 files changed, 10 insertions, 0 deletions
diff --git a/mm/internal.h b/mm/internal.h
index a3110c02aea..953f941ea86 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -37,4 +37,14 @@ static inline void __put_page(struct page *page)
extern void fastcall __init __free_pages_bootmem(struct page *page,
unsigned int order);
+ * function for dealing with page's order in buddy system.
+ * zone->lock is already acquired when we use these.
+ * So, we don't need atomic page->flags operations here.
+ */
+static inline unsigned long page_order(struct page *page)
+ VM_BUG_ON(!PageBuddy(page));
+ return page_private(page);