summaryrefslogtreecommitdiff
path: root/include/linux/mmdebug.h
diff options
context:
space:
mode:
authorDave Hansen <dave.hansen@linux.intel.com>2014-06-04 16:07:02 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-06-04 16:53:58 -0700
commite4f674229ce63dac60be0c4ddfb5ef8d1225d30d (patch)
treedc271d2e95ab57c72db32978de7e2a24924e1ea9 /include/linux/mmdebug.h
parent3dae7fec5e884a4e72e5416db0894de66f586201 (diff)
mm: pass VM_BUG_ON() reason to dump_page()
I recently added a patch to let folks pass a "reason" string dump_page() which gets dumped out along with the page's data. This essentially saves the bug-reader a trip in to the source to figure out why we BUG_ON()'d. The new VM_BUG_ON_PAGE() passes in NULL for "reason". It seems like we might as well pass the BUG_ON() condition if we have it. This will bloat kernels a bit with ~160 new strings, but this is all under a debugging option anyway. page:ffffea0008560280 count:1 mapcount:0 mapping:(null) index:0x0 page flags: 0xbfffc0000000001(locked) page dumped because: VM_BUG_ON_PAGE(PageLocked(page)) ------------[ cut here ]------------ kernel BUG at /home/davehans/linux.git/mm/filemap.c:464! invalid opcode: 0000 [#1] SMP CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.0+ #251 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 ... [akpm@linux-foundation.org: include stringify.h] Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Davidlohr Bueso <davidlohr@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/mmdebug.h')
-rw-r--r--include/linux/mmdebug.h11
1 files changed, 9 insertions, 2 deletions
diff --git a/include/linux/mmdebug.h b/include/linux/mmdebug.h
index a3499d7b0e8a..edd82a105220 100644
--- a/include/linux/mmdebug.h
+++ b/include/linux/mmdebug.h
@@ -1,6 +1,8 @@
#ifndef LINUX_MM_DEBUG_H
#define LINUX_MM_DEBUG_H 1
+#include <linux/stringify.h>
+
struct page;
extern void dump_page(struct page *page, const char *reason);
@@ -9,8 +11,13 @@ extern void dump_page_badflags(struct page *page, const char *reason,
#ifdef CONFIG_DEBUG_VM
#define VM_BUG_ON(cond) BUG_ON(cond)
-#define VM_BUG_ON_PAGE(cond, page) \
- do { if (unlikely(cond)) { dump_page(page, NULL); BUG(); } } while (0)
+#define VM_BUG_ON_PAGE(cond, page) \
+ do { \
+ if (unlikely(cond)) { \
+ dump_page(page, "VM_BUG_ON_PAGE(" __stringify(cond)")");\
+ BUG(); \
+ } \
+ } while (0)
#define VM_WARN_ON(cond) WARN_ON(cond)
#define VM_WARN_ON_ONCE(cond) WARN_ON_ONCE(cond)
#else