mm: rename page_order() to buddy_order()
The current page_order() can only be called on pages in the buddy
allocator. For compound pages, you have to use compound_order(). This is
confusing and led to a bug, so rename page_order() to buddy_order().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/20201001152259.14932-2-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 83692b9..abbf422 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -88,7 +88,7 @@ static void unset_migratetype_isolate(struct page *page, unsigned migratetype)
* these pages to be merged.
*/
if (PageBuddy(page)) {
- order = page_order(page);
+ order = buddy_order(page);
if (order >= pageblock_order) {
pfn = page_to_pfn(page);
buddy_pfn = __find_buddy_pfn(pfn, order);
@@ -261,7 +261,7 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
* the correct MIGRATE_ISOLATE freelist. There is no
* simple way to verify that as VM_BUG_ON(), though.
*/
- pfn += 1 << page_order(page);
+ pfn += 1 << buddy_order(page);
else if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
/* A HWPoisoned page cannot be also PageBuddy */
pfn++;