#define RT_OBJECT_HOOK_CALL(func, argv) __on_##func argv

RT_OBJECT_HOOK_CALL(rt_object_attach_hook, (object));

#define RT_OBJECT_HOOK_CALL(func, argv)         __on_##func argv
展开后：__on_rt_object_attach_hook(object);

#define __on_rt_object_attach_hook(obj)         __ON_HOOK_ARGS(rt_object_attach_hook, (obj))
#define __ON_HOOK_ARGS(__hook, argv)        do {if ((__hook) != RT_NULL) __hook argv; } while (0)
其实就是执行了一次rt_object_attach_hook函数；