[Devel] [PATCH v3 1/6] measure exec_clock for rt sched entities

[Glauber Costa]

For simetry with the cfq tasks, measure exec_clock for the rt
sched entities (rt_se).

This can be used in a number of fashions. For instance, to
compute total cpu usage in a cgroup that is generated by
rt tasks.

Signed-off-by: Glauber Costa <glommer at parallels.com>
CC: Peter Zijlstra <a.p.zijlstra at chello.nl>
CC: Paul Turner <pjt at google.com>
---
 kernel/sched/rt.c    |    5 +++++
 kernel/sched/sched.h |    1 +
 2 files changed, 6 insertions(+)

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index c5565c3..30ee4e2 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -919,6 +919,11 @@ static void update_curr_rt(struct rq *rq)
 
 	sched_rt_avg_update(rq, delta_exec);
 
+	for_each_sched_rt_entity(rt_se) {
+		rt_rq = rt_rq_of_se(rt_se);
+		schedstat_add(rt_rq, exec_clock, delta_exec);
+	}
+
 	if (!rt_bandwidth_enabled())
 		return;
 
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index ba9dccf..cd2f1e1 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -295,6 +295,7 @@ struct rt_rq {
 	struct plist_head pushable_tasks;
 #endif
 	int rt_throttled;
+	u64 exec_clock;
 	u64 rt_time;
 	u64 rt_runtime;
 	/* Nests inside the rq lock: */
-- 
1.7.10.2