1 files changed, 30 insertions, 40 deletions

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index ce203154d8c..eb768ce8867 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -76,6 +76,7 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
  * Need to know about CPUs going idle?
  */
 static ATOMIC_NOTIFIER_HEAD(idle_chain);
+DEFINE_PER_CPU(struct s390_idle_data, s390_idle);
 
 int register_idle_notifier(struct notifier_block *nb)
 {
@@ -89,9 +90,33 @@ int unregister_idle_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL(unregister_idle_notifier);
 
-void do_monitor_call(struct pt_regs *regs, long interruption_code)
+static int s390_idle_enter(void)
+{
+	struct s390_idle_data *idle;
+	int nr_calls = 0;
+	void *hcpu;
+	int rc;
+
+	hcpu = (void *)(long)smp_processor_id();
+	rc = __atomic_notifier_call_chain(&idle_chain, S390_CPU_IDLE, hcpu, -1,
+					  &nr_calls);
+	if (rc == NOTIFY_BAD) {
+		nr_calls--;
+		__atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,
+					     hcpu, nr_calls, NULL);
+		return rc;
+	}
+	idle = &__get_cpu_var(s390_idle);
+	spin_lock(&idle->lock);
+	idle->idle_count++;
+	idle->in_idle = 1;
+	idle->idle_enter = get_clock();
+	spin_unlock(&idle->lock);
+	return NOTIFY_OK;
+}
+
+void s390_idle_leave(void)
 {
-#ifdef CONFIG_SMP
 	struct s390_idle_data *idle;
 
 	idle = &__get_cpu_var(s390_idle);
@@ -99,10 +124,6 @@ void do_monitor_call(struct pt_regs *regs, long interruption_code)
 	idle->idle_time += get_clock() - idle->idle_enter;
 	idle->in_idle = 0;
 	spin_unlock(&idle->lock);
-#endif
-	/* disable monitor call class 0 */
-	__ctl_clear_bit(8, 15);
-
 	atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,
 				   (void *)(long) smp_processor_id());
 }
@@ -113,61 +134,30 @@ extern void s390_handle_mcck(void);
  */
 static void default_idle(void)
 {
-	int cpu, rc;
-	int nr_calls = 0;
-	void *hcpu;
-#ifdef CONFIG_SMP
-	struct s390_idle_data *idle;
-#endif
-
 	/* CPU is going idle. */
-	cpu = smp_processor_id();
-	hcpu = (void *)(long)cpu;
 	local_irq_disable();
 	if (need_resched()) {
 		local_irq_enable();
 		return;
 	}
-
-	rc = __atomic_notifier_call_chain(&idle_chain, S390_CPU_IDLE, hcpu, -1,
-					  &nr_calls);
-	if (rc == NOTIFY_BAD) {
-		nr_calls--;
-		__atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,
-					     hcpu, nr_calls, NULL);
+	if (s390_idle_enter() == NOTIFY_BAD) {
 		local_irq_enable();
 		return;
 	}
-
-	/* enable monitor call class 0 */
-	__ctl_set_bit(8, 15);
-
 #ifdef CONFIG_HOTPLUG_CPU
-	if (cpu_is_offline(cpu)) {
+	if (cpu_is_offline(smp_processor_id())) {
 		preempt_enable_no_resched();
 		cpu_die();
 	}
 #endif
-
 	local_mcck_disable();
 	if (test_thread_flag(TIF_MCCK_PENDING)) {
 		local_mcck_enable();
-		/* disable monitor call class 0 */
-		__ctl_clear_bit(8, 15);
-		atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,
-					   hcpu);
+		s390_idle_leave();
 		local_irq_enable();
 		s390_handle_mcck();
 		return;
 	}
-#ifdef CONFIG_SMP
-	idle = &__get_cpu_var(s390_idle);
-	spin_lock(&idle->lock);
-	idle->idle_count++;
-	idle->in_idle = 1;
-	idle->idle_enter = get_clock();
-	spin_unlock(&idle->lock);
-#endif
 	trace_hardirqs_on();
 	/* Wait for external, I/O or machine check interrupt. */
 	__load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT |