sched: make sched_{rt,fair}.c ifdefs more readable

Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched_fair.c

@@ -921,7 +921,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
 		hrtick_start(rq, delta, requeue);
 	}
 }
-#else
+#else /* !CONFIG_SCHED_HRTICK */
 static inline void
 hrtick_start_fair(struct rq *rq, struct task_struct *p)
 {
@@ -1062,7 +1062,7 @@ static int wake_idle(int cpu, struct task_struct *p)
 	}
 	return cpu;
 }
-#else
+#else /* !ARCH_HAS_SCHED_WAKE_IDLE*/
 static inline int wake_idle(int cpu, struct task_struct *p)
 {
 	return cpu;
@@ -1586,7 +1586,7 @@ move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
 
 	return 0;
 }
-#endif
+#endif /* CONFIG_SMP */
 
 /*
  * scheduler tick hitting a task of our scheduling class:

kernel/sched_rt.c

@@ -161,7 +161,7 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
 	return &rt_rq->tg->rt_bandwidth;
 }
 
-#else
+#else /* !CONFIG_RT_GROUP_SCHED */
 
 static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
 {
@@ -226,7 +226,7 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
 	return &def_rt_bandwidth;
 }
 
-#endif
+#endif /* CONFIG_RT_GROUP_SCHED */
 
 #ifdef CONFIG_SMP
 static int do_balance_runtime(struct rt_rq *rt_rq)
@@ -374,12 +374,12 @@ static int balance_runtime(struct rt_rq *rt_rq)
 
 	return more;
 }
-#else
+#else /* !CONFIG_SMP */
 static inline int balance_runtime(struct rt_rq *rt_rq)
 {
 	return 0;
 }
-#endif
+#endif /* CONFIG_SMP */
 
 static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
 {
@@ -1472,4 +1472,4 @@ static void print_rt_stats(struct seq_file *m, int cpu)
 		print_rt_rq(m, cpu, rt_rq);
 	rcu_read_unlock();
 }
-#endif
+#endif /* CONFIG_SCHED_DEBUG */