[tip:perf/core] perf sched replay: Use replay_repeat to calculate the runavg of cpu usage instead of the default value 10

From: tip-bot for Yunlong Song
Date: Wed Apr 08 2015 - 11:14:23 EST


Commit-ID: ff5f3bbd40bfb8632f826f1f83223d95363f36af
Gitweb: http://git.kernel.org/tip/ff5f3bbd40bfb8632f826f1f83223d95363f36af
Author: Yunlong Song <yunlong.song@xxxxxxxxxx>
AuthorDate: Tue, 31 Mar 2015 21:46:36 +0800
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 8 Apr 2015 09:07:27 -0300

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@xxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1427809596-29559-10-git-send-email-yunlong.song@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-sched.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 7b7b798..5275bab 100644
--- a/tools/perf/builtin-sched.c
+++ b/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);

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