sched/nohz: Clean up select_nohz_load_balancer()

There is no load_balancer to be selected now. It just sets the
state of the nohz tick to stop.

So rename the function, pass the 'cpu' as a parameter and then
remove the useless call from tick_nohz_restart_sched_tick().

[ s/set_nohz_tick_stopped/nohz_balance_enter_idle/g
  s/clear_nohz_tick_stopped/nohz_balance_exit_idle/g ]
Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1347261059-24747-1-git-send-email-alex.shi@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 10 insertions, 15 deletions

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 9ae3a5b68ba4..de596a2f626c 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4603,7 +4603,7 @@ static void nohz_balancer_kick(int cpu)
         return;
 }
 
-static inline void clear_nohz_tick_stopped(int cpu)
+static inline void nohz_balance_exit_idle(int cpu)
 {
         if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
                 cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
@@ -4643,28 +4643,23 @@ void set_cpu_sd_state_idle(void)
 }
 
 /*
- * This routine will record that this cpu is going idle with tick stopped.
+ * This routine will record that the cpu is going idle with tick stopped.
  * This info will be used in performing idle load balancing in the future.
  */
-void select_nohz_load_balancer(int stop_tick)
+void nohz_balance_enter_idle(int cpu)
 {
-        int cpu = smp_processor_id();
-
         /*
          * If this cpu is going down, then nothing needs to be done.
          */
         if (!cpu_active(cpu))
                 return;
 
-        if (stop_tick) {
-                if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))
-                        return;
+        if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))
+                return;
 
-                cpumask_set_cpu(cpu, nohz.idle_cpus_mask);
-                atomic_inc(&nohz.nr_cpus);
-                set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
-        }
-        return;
+        cpumask_set_cpu(cpu, nohz.idle_cpus_mask);
+        atomic_inc(&nohz.nr_cpus);
+        set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
 }
 
 static int __cpuinit sched_ilb_notifier(struct notifier_block *nfb,
@@ -4672,7 +4667,7 @@ static int __cpuinit sched_ilb_notifier(struct notifier_block *nfb,
 {
         switch (action & ~CPU_TASKS_FROZEN) {
         case CPU_DYING:
-                clear_nohz_tick_stopped(smp_processor_id());
+                nohz_balance_exit_idle(smp_processor_id());
                 return NOTIFY_OK;
         default:
                 return NOTIFY_DONE;
@@ -4833,7 +4828,7 @@ static inline int nohz_kick_needed(struct rq *rq, int cpu)
         * busy tick after returning from idle, we will update the busy stats.
         */
         set_cpu_sd_state_busy();
-        clear_nohz_tick_stopped(cpu);
+        nohz_balance_exit_idle(cpu);
 
         /*
          * None are in tickless mode and hence no need for NOHZ idle load