sched/accounting: Change cpustat fields to an array

This patch changes fields in cpustat from a structure, to an
u64 array. Math gets easier, and the code is more flexible.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Tuner <pjt@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1322498719-2255-2-git-send-email-glommer@parallels.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/drivers/macintosh/rack-meter.c b/drivers/macintosh/rack-meter.c
index 2637c13..66d7f1c7 100644
--- a/drivers/macintosh/rack-meter.c
+++ b/drivers/macintosh/rack-meter.c
@@ -81,13 +81,13 @@
  */
 static inline cputime64_t get_cpu_idle_time(unsigned int cpu)
 {
-	cputime64_t retval;
+	u64 retval;
 
-	retval = cputime64_add(kstat_cpu(cpu).cpustat.idle,
-			kstat_cpu(cpu).cpustat.iowait);
+	retval = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE] +
+		 kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
 
 	if (rackmeter_ignore_nice)
-		retval = cputime64_add(retval, kstat_cpu(cpu).cpustat.nice);
+		retval += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE];
 
 	return retval;
 }