perf sched replay: Use replay_repeat to calculate the runavg of cpu usage instead of the default value 10

Since sched->replay_repeat is set to 10 as default, the sched->run_avg,
sched->runavg_cpu_usage, and sched->runavg_parent_cpu_usage all use
10 to calculate their value.

However, the replay_repeat can be changed to other value by using -r
option, so the calculation above should use replay_repeat to achieve
more accurate results instead of the default value 10.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1427809596-29559-10-git-send-email-yunlong.song@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-sched.c

@@ -607,13 +607,13 @@ static void wait_for_tasks(struct perf_sched *sched)
 	cpu_usage_1 = get_cpu_usage_nsec_parent();
 	if (!sched->runavg_cpu_usage)
 		sched->runavg_cpu_usage = sched->cpu_usage;
-	sched->runavg_cpu_usage = (sched->runavg_cpu_usage * 9 + sched->cpu_usage) / 10;
+	sched->runavg_cpu_usage = (sched->runavg_cpu_usage * (sched->replay_repeat - 1) + sched->cpu_usage) / sched->replay_repeat;
 
 	sched->parent_cpu_usage = cpu_usage_1 - cpu_usage_0;
 	if (!sched->runavg_parent_cpu_usage)
 		sched->runavg_parent_cpu_usage = sched->parent_cpu_usage;
-	sched->runavg_parent_cpu_usage = (sched->runavg_parent_cpu_usage * 9 +
-					 sched->parent_cpu_usage)/10;
+	sched->runavg_parent_cpu_usage = (sched->runavg_parent_cpu_usage * (sched->replay_repeat - 1) +
+					 sched->parent_cpu_usage)/sched->replay_repeat;
 
 	ret = pthread_mutex_lock(&sched->start_work_mutex);
 	BUG_ON(ret);
@@ -645,7 +645,7 @@ static void run_one_test(struct perf_sched *sched)
 	sched->sum_fluct += fluct;
 	if (!sched->run_avg)
 		sched->run_avg = delta;
-	sched->run_avg = (sched->run_avg * 9 + delta) / 10;
+	sched->run_avg = (sched->run_avg * (sched->replay_repeat - 1) + delta) / sched->replay_repeat;
 
 	printf("#%-3ld: %0.3f, ", sched->nr_runs, (double)delta / 1000000.0);