debugobjects: Extend to assert that an object is initialized

Calling del_timer_sync() on an uninitialized timer leads to a
never ending loop in lock_timer_base() that spins checking for a
non-NULL timer base. Add an assertion to debugobjects to catch
usage of uninitialized objects so that we can initialize timers
in the del_timer_sync() path before it calls lock_timer_base().

[ sboyd@codeaurora.org: Clarify commit message ]

Signed-off-by: Christine Chan <cschan@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1320724108-20788-3-git-send-email-sboyd@codeaurora.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/debugobjects.h b/include/linux/debugobjects.h
index 65970b8..0e5f578 100644
--- a/include/linux/debugobjects.h
+++ b/include/linux/debugobjects.h
@@ -46,6 +46,8 @@
  *			fails
  * @fixup_free:		fixup function, which is called when the free check
  *			fails
+ * @fixup_assert_init:  fixup function, which is called when the assert_init
+ *			check fails
  */
 struct debug_obj_descr {
 	const char		*name;
@@ -54,6 +56,7 @@
 	int (*fixup_activate)	(void *addr, enum debug_obj_state state);
 	int (*fixup_destroy)	(void *addr, enum debug_obj_state state);
 	int (*fixup_free)	(void *addr, enum debug_obj_state state);
+	int (*fixup_assert_init)(void *addr, enum debug_obj_state state);
 };
 
 #ifdef CONFIG_DEBUG_OBJECTS
@@ -64,6 +67,7 @@
 extern void debug_object_deactivate(void *addr, struct debug_obj_descr *descr);
 extern void debug_object_destroy   (void *addr, struct debug_obj_descr *descr);
 extern void debug_object_free      (void *addr, struct debug_obj_descr *descr);
+extern void debug_object_assert_init(void *addr, struct debug_obj_descr *descr);
 
 /*
  * Active state:
@@ -89,6 +93,8 @@
 debug_object_destroy   (void *addr, struct debug_obj_descr *descr) { }
 static inline void
 debug_object_free      (void *addr, struct debug_obj_descr *descr) { }
+static inline void
+debug_object_assert_init(void *addr, struct debug_obj_descr *descr) { }
 
 static inline void debug_objects_early_init(void) { }
 static inline void debug_objects_mem_init(void) { }