3 files changed, 18 insertions, 11 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 6bdaa73ede13..a25168f4ab86 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -808,6 +808,8 @@ struct sched_domain {
         unsigned int wake_idx;
         unsigned int forkexec_idx;
         unsigned int smt_gain;
+
+        int nohz_idle;                  /* NOHZ IDLE status */
         int flags;                      /* See SD_* */
         int level;
 
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index acaf567a03d2..8bf7081b1ec5 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5420,13 +5420,16 @@ static inline void set_cpu_sd_state_busy(void)
         struct sched_domain *sd;
         int cpu = smp_processor_id();
 
-        if (!test_bit(NOHZ_IDLE, nohz_flags(cpu)))
-                return;
-        clear_bit(NOHZ_IDLE, nohz_flags(cpu));
-
         rcu_read_lock();
-        for_each_domain(cpu, sd)
+        sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd);
+
+        if (!sd || !sd->nohz_idle)
+                goto unlock;
+        sd->nohz_idle = 0;
+
+        for (; sd; sd = sd->parent)
                 atomic_inc(&sd->groups->sgp->nr_busy_cpus);
+unlock:
         rcu_read_unlock();
 }
 
@@ -5435,13 +5438,16 @@ void set_cpu_sd_state_idle(void)
         struct sched_domain *sd;
         int cpu = smp_processor_id();
 
-        if (test_bit(NOHZ_IDLE, nohz_flags(cpu)))
-                return;
-        set_bit(NOHZ_IDLE, nohz_flags(cpu));
-
         rcu_read_lock();
-        for_each_domain(cpu, sd)
+        sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd);
+
+        if (!sd || sd->nohz_idle)
+                goto unlock;
+        sd->nohz_idle = 1;
+
+        for (; sd; sd = sd->parent)
                 atomic_dec(&sd->groups->sgp->nr_busy_cpus);
+unlock:
         rcu_read_unlock();
 }
 
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 605426a63588..4c225c4c7111 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1303,7 +1303,6 @@ extern void account_cfs_bandwidth_used(int enabled, int was_enabled);
 enum rq_nohz_flag_bits {
         NOHZ_TICK_STOPPED,
         NOHZ_BALANCE_KICK,
-        NOHZ_IDLE,
 };
 
 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)