sched: revert revert of: fair-group: SMP-nice for group scheduling

Try again..

Initial commit: 18d95a2832c1392a2d63227a7a6d433cb9f2037e
Revert: 6363ca57c76b7b83639ca8c83fc285fa26a7880e

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 6b4a6b5..765932d 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -670,6 +670,8 @@
 		rt_se->timeout = 0;
 
 	enqueue_rt_entity(rt_se);
+
+	inc_cpu_load(rq, p->se.load.weight);
 }
 
 static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
@@ -678,6 +680,8 @@
 
 	update_curr_rt(rq);
 	dequeue_rt_entity(rt_se);
+
+	dec_cpu_load(rq, p->se.load.weight);
 }
 
 /*