set_page_refcounted() VM_BUG_ON fix

Qi Yong · Linus Torvalds · commit ae1276b9349a · 2008-02-05T09:44:19.000-08:00
The current PageTail semantic is that a PageTail page is first a
PageCompound page.  So remove the redundant PageCompound test in
set_page_refcounted().

Signed-off-by: Qi Yong &lt;qiyong@fc-cn.com&gt;
Cc: Christoph Lameter &lt;clameter@sgi.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
diff --git a/mm/internal.h b/mm/internal.h
@@ -24,7 +24,7 @@ static inline void set_page_count(struct page *page, int v)
  */
 static inline void set_page_refcounted(struct page *page)
 {
-	VM_BUG_ON(PageCompound(page) && PageTail(page));
+	VM_BUG_ON(PageTail(page));
 	VM_BUG_ON(atomic_read(&page->_count));
 	set_page_count(page, 1);
 }

Original file line number	Diff line number	Diff line change
`@@ -24,7 +24,7 @@ static inline void set_page_count(struct page *page, int v)`
`24`	`24`	`*/`
`25`	`25`	`static inline void set_page_refcounted(struct page *page)`
`26`	`26`	`{`
`27`		`- VM_BUG_ON(PageCompound(page) && PageTail(page));`
	`27`	`+ VM_BUG_ON(PageTail(page));`
`28`	`28`	`VM_BUG_ON(atomic_read(&page->_count));`
`29`	`29`	`set_page_count(page, 1);`
`30`	`30`	`}`