+int __cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+ struct task_struct *p;
+ int ret;
+
+ ret = mp_ops->cpu_disable(cpu);
+ if (ret)
+ return ret;
+
+ /*
+ * Take this CPU offline. Once we clear this, we can't return,
+ * and we must not schedule until we're ready to give up the cpu.
+ */
+ set_cpu_online(cpu, false);
+
+ /*
+ * OK - migrate IRQs away from this CPU
+ */
+ migrate_irqs();
+
+ /*
+ * Stop the local timer for this CPU.
+ */
+ local_timer_stop(cpu);
+
+ /*
+ * Flush user cache and TLB mappings, and then remove this CPU
+ * from the vm mask set of all processes.
+ */
+ flush_cache_all();
+ local_flush_tlb_all();
+
+ read_lock(&tasklist_lock);
+ for_each_process(p)
+ if (p->mm)
+ cpumask_clear_cpu(cpu, mm_cpumask(p->mm));
+ read_unlock(&tasklist_lock);
+
+ return 0;
+}
+#else /* ... !CONFIG_HOTPLUG_CPU */
+int native_cpu_disable(unsigned int cpu)
+{
+ return -ENOSYS;
+}
+
+void native_cpu_die(unsigned int cpu)
+{
+ /* We said "no" in __cpu_disable */
+ BUG();
+}
+
+void native_play_dead(void)
+{
+ BUG();
+}
+#endif
+