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, 3 insertions, 3 deletions

diff --git a/mm/cleancache.c b/mm/cleancache.c
index 5875f48ce279..d0eac4350403 100644
--- a/mm/cleancache.c
+++ b/mm/cleancache.c
@@ -237,7 +237,7 @@ int __cleancache_get_page(struct page *page)
                 goto out;
         }
 
-        VM_BUG_ON(!PageLocked(page));
+        VM_BUG_ON_PAGE(!PageLocked(page), page);
         fake_pool_id = page->mapping->host->i_sb->cleancache_poolid;
         if (fake_pool_id < 0)
                 goto out;
@@ -279,7 +279,7 @@ void __cleancache_put_page(struct page *page)
                 return;
         }
 
-        VM_BUG_ON(!PageLocked(page));
+        VM_BUG_ON_PAGE(!PageLocked(page), page);
         fake_pool_id = page->mapping->host->i_sb->cleancache_poolid;
         if (fake_pool_id < 0)
                 return;
@@ -318,7 +318,7 @@ void __cleancache_invalidate_page(struct address_space *mapping,
                 if (pool_id < 0)
                         return;
 
-                VM_BUG_ON(!PageLocked(page));
+                VM_BUG_ON_PAGE(!PageLocked(page), page);
                 if (cleancache_get_key(mapping->host, &key) >= 0) {
                         cleancache_ops->invalidate_page(pool_id,
                                         key, page->index);