+extern int register_cpu(struct cpu *cpu, int num);
+extern struct sys_device *get_cpu_sysdev(unsigned cpu);
+
+extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr);
+extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr);
+
+extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs);
+extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs);
+
+
+#ifdef CONFIG_HOTPLUG_CPU
+extern void unregister_cpu(struct cpu *cpu);
+#endif