3 files changed, 27 insertions, 9 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 9004f6e19eac..10626e2ee688 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1851,9 +1851,9 @@ static inline void idle_task_exit(void) {}
 #endif
 
 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
-extern void wake_up_idle_cpu(int cpu);
+extern void wake_up_nohz_cpu(int cpu);
 #else
-static inline void wake_up_idle_cpu(int cpu) { }
+static inline void wake_up_nohz_cpu(int cpu) { }
 #endif
 
 #ifdef CONFIG_SCHED_AUTOGROUP
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 849deb96e61e..e91ee589f793 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -587,7 +587,7 @@ unlock:
  * account when the CPU goes back to idle and evaluates the timer
  * wheel for the next timer event.
  */
-void wake_up_idle_cpu(int cpu)
+static void wake_up_idle_cpu(int cpu)
 {
         struct rq *rq = cpu_rq(cpu);
 
@@ -617,6 +617,24 @@ void wake_up_idle_cpu(int cpu)
                 smp_send_reschedule(cpu);
 }
 
+static bool wake_up_extended_nohz_cpu(int cpu)
+{
+        if (tick_nohz_extended_cpu(cpu)) {
+                if (cpu != smp_processor_id() ||
+                    tick_nohz_tick_stopped())
+                        smp_send_reschedule(cpu);
+                return true;
+        }
+
+        return false;
+}
+
+void wake_up_nohz_cpu(int cpu)
+{
+        if (!wake_up_extended_nohz_cpu(cpu))
+                wake_up_idle_cpu(cpu);
+}
+
 static inline bool got_nohz_idle_kick(void)
 {
         int cpu = smp_processor_id();
diff --git a/kernel/timer.c b/kernel/timer.c
index dbf7a78a1ef1..4e3040b40d16 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -930,14 +930,14 @@ void add_timer_on(struct timer_list *timer, int cpu)
         debug_activate(timer, timer->expires);
         internal_add_timer(base, timer);
         /*
-         * Check whether the other CPU is idle and needs to be
-         * triggered to reevaluate the timer wheel when nohz is
-         * active. We are protected against the other CPU fiddling
+         * Check whether the other CPU is in dynticks mode and needs
+         * to be triggered to reevaluate the timer wheel.
+         * We are protected against the other CPU fiddling
          * with the timer by holding the timer base lock. This also
-         * makes sure that a CPU on the way to idle can not evaluate
-         * the timer wheel.
+         * makes sure that a CPU on the way to stop its tick can not
+         * evaluate the timer wheel.
          */
-        wake_up_idle_cpu(cpu);
+        wake_up_nohz_cpu(cpu);
         spin_unlock_irqrestore(&base->lock, flags);
 }
 EXPORT_SYMBOL_GPL(add_timer_on);