mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE

Most of the VM_BUG_ON assertions are performed on a page.  Usually, when
one of these assertions fails we'll get a BUG_ON with a call stack and
the registers.

I've recently noticed based on the requests to add a small piece of code
that dumps the page to various VM_BUG_ON sites that the page dump is
quite useful to people debugging issues in mm.

This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what
VM_BUG_ON() does, also dumps the page before executing the actual
BUG_ON.

[akpm@linux-foundation.org: fix up includes]
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 5 deletions

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 98ada58..e464b4e 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -412,7 +412,7 @@ static inline void ClearPageCompound(struct page *page)
  */
 static inline int PageTransHuge(struct page *page)
 {
-	VM_BUG_ON(PageTail(page));
+	VM_BUG_ON_PAGE(PageTail(page), page);
 	return PageHead(page);
 }
 
@@ -460,25 +460,25 @@ static inline int PageTransTail(struct page *page)
  */
 static inline int PageSlabPfmemalloc(struct page *page)
 {
-	VM_BUG_ON(!PageSlab(page));
+	VM_BUG_ON_PAGE(!PageSlab(page), page);
 	return PageActive(page);
 }
 
 static inline void SetPageSlabPfmemalloc(struct page *page)
 {
-	VM_BUG_ON(!PageSlab(page));
+	VM_BUG_ON_PAGE(!PageSlab(page), page);
 	SetPageActive(page);
 }
 
 static inline void __ClearPageSlabPfmemalloc(struct page *page)
 {
-	VM_BUG_ON(!PageSlab(page));
+	VM_BUG_ON_PAGE(!PageSlab(page), page);
 	__ClearPageActive(page);
 }
 
 static inline void ClearPageSlabPfmemalloc(struct page *page)
 {
-	VM_BUG_ON(!PageSlab(page));
+	VM_BUG_ON_PAGE(!PageSlab(page), page);
 	ClearPageActive(page);
 }