debugobjects: make fixup functions return bool instead of int

I am going to introduce debugobjects infrastructure to USB subsystem.
But before this, I found the code of debugobjects could be improved.
This patchset will make fixup functions return bool type instead of int.
Because fixup only need report success or no.  boolean is the 'real'
type.

This patch (of 7):

The object debugging infrastructure core provides some fixup callbacks
for the subsystem who use it.  These callbacks are called from the debug
code whenever a problem in debug_object_init is detected.  And
debugobjects core suppose them returns 1 when the fixup was successful,
otherwise 0.  So the return type is boolean.

A bad thing is that debug_object_fixup use the return value for
arithmetic operation.  It confused me that what is the reall return
type.

Reading over the whole code, I found some place do use the return value
incorrectly(see next patch).  So why use bool type instead?

Signed-off-by: Du, Changbin <changbin.du@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Triplett <josh@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/debugobjects.h

@@ -39,7 +39,8 @@ struct debug_obj {
  * @debug_hint:		function returning address, which have associated
  *			kernel symbol, to allow identify the object
  * @fixup_init:		fixup function, which is called when the init check
- *			fails
+ *			fails. All fixup functions must return true if fixup
+ *			was successful, otherwise return false
  * @fixup_activate:	fixup function, which is called when the activate check
  *			fails
  * @fixup_destroy:	fixup function, which is called when the destroy check
@@ -51,12 +52,12 @@ struct debug_obj {
  */
 struct debug_obj_descr {
 	const char		*name;
-	void *(*debug_hint)	(void *addr);
-	int (*fixup_init)	(void *addr, enum debug_obj_state state);
-	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);
+	void *(*debug_hint)(void *addr);
+	bool (*fixup_init)(void *addr, enum debug_obj_state state);
+	bool (*fixup_activate)(void *addr, enum debug_obj_state state);
+	bool (*fixup_destroy)(void *addr, enum debug_obj_state state);
+	bool (*fixup_free)(void *addr, enum debug_obj_state state);
+	bool (*fixup_assert_init)(void *addr, enum debug_obj_state state);
 };
 
 #ifdef CONFIG_DEBUG_OBJECTS

lib/debugobjects.c

@@ -269,16 +269,15 @@ static void debug_print_object(struct debug_obj *obj, char *msg)
  * Try to repair the damage, so we have a better chance to get useful
  * debug output.
  */
-static int
-debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),
+static bool
+debug_object_fixup(bool (*fixup)(void *addr, enum debug_obj_state state),
 		   void * addr, enum debug_obj_state state)
 {
-	int fixed = 0;
-
-	if (fixup)
-		fixed = fixup(addr, state);
-	debug_objects_fixups += fixed;
-	return fixed;
+	if (fixup && fixup(addr, state)) {
+		debug_objects_fixups++;
+		return true;
+	}
+	return false;
 }
 
 static void debug_object_is_on_stack(void *addr, int onstack)
@@ -797,7 +796,7 @@ static __initdata struct debug_obj_descr descr_type_test;
  * fixup_init is called when:
  * - an active object is initialized
  */
-static int __init fixup_init(void *addr, enum debug_obj_state state)
+static bool __init fixup_init(void *addr, enum debug_obj_state state)
 {
 	struct self_test *obj = addr;
 
@@ -805,9 +804,9 @@ static int __init fixup_init(void *addr, enum debug_obj_state state)
 	case ODEBUG_STATE_ACTIVE:
 		debug_object_deactivate(obj, &descr_type_test);
 		debug_object_init(obj, &descr_type_test);
-		return 1;
+		return true;
 	default:
-		return 0;
+		return false;
 	}
 }
 
@@ -816,7 +815,7 @@ static int __init fixup_init(void *addr, enum debug_obj_state state)
  * - an active object is activated
  * - an unknown object is activated (might be a statically initialized object)
  */
-static int __init fixup_activate(void *addr, enum debug_obj_state state)
+static bool __init fixup_activate(void *addr, enum debug_obj_state state)
 {
 	struct self_test *obj = addr;
 
@@ -825,17 +824,17 @@ static int __init fixup_activate(void *addr, enum debug_obj_state state)
 		if (obj->static_init == 1) {
 			debug_object_init(obj, &descr_type_test);
 			debug_object_activate(obj, &descr_type_test);
-			return 0;
+			return false;
 		}
-		return 1;
+		return true;
 
 	case ODEBUG_STATE_ACTIVE:
 		debug_object_deactivate(obj, &descr_type_test);
 		debug_object_activate(obj, &descr_type_test);
-		return 1;
+		return true;
 
 	default:
-		return 0;
+		return false;
 	}
 }
 
@@ -843,7 +842,7 @@ static int __init fixup_activate(void *addr, enum debug_obj_state state)
  * fixup_destroy is called when:
  * - an active object is destroyed
  */
-static int __init fixup_destroy(void *addr, enum debug_obj_state state)
+static bool __init fixup_destroy(void *addr, enum debug_obj_state state)
 {
 	struct self_test *obj = addr;
 
@@ -851,9 +850,9 @@ static int __init fixup_destroy(void *addr, enum debug_obj_state state)
 	case ODEBUG_STATE_ACTIVE:
 		debug_object_deactivate(obj, &descr_type_test);
 		debug_object_destroy(obj, &descr_type_test);
-		return 1;
+		return true;
 	default:
-		return 0;
+		return false;
 	}
 }
 
@@ -861,7 +860,7 @@ static int __init fixup_destroy(void *addr, enum debug_obj_state state)
  * fixup_free is called when:
  * - an active object is freed
  */
-static int __init fixup_free(void *addr, enum debug_obj_state state)
+static bool __init fixup_free(void *addr, enum debug_obj_state state)
 {
 	struct self_test *obj = addr;
 
@@ -869,9 +868,9 @@ static int __init fixup_free(void *addr, enum debug_obj_state state)
 	case ODEBUG_STATE_ACTIVE:
 		debug_object_deactivate(obj, &descr_type_test);
 		debug_object_free(obj, &descr_type_test);
-		return 1;
+		return true;
 	default:
-		return 0;
+		return false;
 	}
 }