2 files changed, 11 insertions, 14 deletions

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 6abb03dff5c0..08a765232432 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1632,7 +1632,7 @@ module_param(rcu_idle_gp_delay, int, 0644);
 static int rcu_idle_lazy_gp_delay = RCU_IDLE_LAZY_GP_DELAY;
 module_param(rcu_idle_lazy_gp_delay, int, 0644);
 
-extern int tick_nohz_enabled;
+extern int tick_nohz_active;
 
 /*
  * Try to advance callbacks for all flavors of RCU on the current CPU, but
@@ -1729,7 +1729,7 @@ static void rcu_prepare_for_idle(int cpu)
         int tne;
 
         /* Handle nohz enablement switches conservatively. */
-        tne = ACCESS_ONCE(tick_nohz_enabled);
+        tne = ACCESS_ONCE(tick_nohz_active);
         if (tne != rdtp->tick_nohz_enabled_snap) {
                 if (rcu_cpu_has_callbacks(cpu, NULL))
                         invoke_rcu_core(); /* force nohz to see update. */
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 3612fc77f834..a12df5abde0b 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -361,8 +361,8 @@ void __init tick_nohz_init(void)
 /*
  * NO HZ enabled ?
  */
-int tick_nohz_enabled __read_mostly  = 1;
-
+static int tick_nohz_enabled __read_mostly  = 1;
+int tick_nohz_active  __read_mostly;
 /*
  * Enable / Disable tickless mode
  */
@@ -465,7 +465,7 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
         struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
         ktime_t now, idle;
 
-        if (!tick_nohz_enabled)
+        if (!tick_nohz_active)
                 return -1;
 
         now = ktime_get();
@@ -506,7 +506,7 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time)
         struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
         ktime_t now, iowait;
 
-        if (!tick_nohz_enabled)
+        if (!tick_nohz_active)
                 return -1;
 
         now = ktime_get();
@@ -799,11 +799,6 @@ void tick_nohz_idle_enter(void)
         local_irq_disable();
 
         ts = &__get_cpu_var(tick_cpu_sched);
-        /*
-         * set ts->inidle unconditionally. even if the system did not
-         * switch to nohz mode the cpu frequency governers rely on the
-         * update of the idle time accounting in tick_nohz_start_idle().
-         */
         ts->inidle = 1;
         __tick_nohz_idle_enter(ts);
 
@@ -973,7 +968,7 @@ static void tick_nohz_switch_to_nohz(void)
         struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched);
         ktime_t next;
 
-        if (!tick_nohz_enabled)
+        if (!tick_nohz_active)
                 return;
 
         local_irq_disable();
@@ -981,7 +976,7 @@ static void tick_nohz_switch_to_nohz(void)
                 local_irq_enable();
                 return;
         }
-
+        tick_nohz_active = 1;
         ts->nohz_mode = NOHZ_MODE_LOWRES;
 
         /*
@@ -1139,8 +1134,10 @@ void tick_setup_sched_timer(void)
         }
 
 #ifdef CONFIG_NO_HZ_COMMON
-        if (tick_nohz_enabled)
+        if (tick_nohz_enabled) {
                 ts->nohz_mode = NOHZ_MODE_HIGHRES;
+                tick_nohz_active = 1;
+        }
 #endif
 }
 #endif /* HIGH_RES_TIMERS */