Subject: sched: Add DL utilization tracking
From: Peter Zijlstra <peterz@infradead.org>
Date: Mon Aug 7 16:49:48 CEST 2017

Track how much time we spend running DL tasks on avgerage.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
 kernel/sched/deadline.c |   11 ++++++++++-
 kernel/sched/fair.c     |   12 ++++++++++++
 kernel/sched/sched.h    |    2 ++
 3 files changed, 24 insertions(+), 1 deletion(-)

--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1655,6 +1655,8 @@ static struct sched_dl_entity *pick_next
 	return rb_entry(left, struct sched_dl_entity, rb_node);
 }
 
+extern int update_dl_rq_load_avg(u64 now, int cpu, struct dl_rq *dl_rq, int running);
+
 struct task_struct *
 pick_next_task_dl(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
 {
@@ -1702,19 +1704,25 @@ pick_next_task_dl(struct rq *rq, struct
 	p->se.exec_start = rq_clock_task(rq);
 
 	/* Running task will never be pushed. */
-       dequeue_pushable_dl_task(rq, p);
+	dequeue_pushable_dl_task(rq, p);
 
 	if (hrtick_enabled(rq))
 		start_hrtick_dl(rq, p);
 
 	queue_push_tasks(rq);
 
+	if (p) {
+		update_dl_rq_load_avg(rq_clock_task(rq), cpu_of(rq), dl_rq,
+				rq->curr->sched_class == &dl_sched_class);
+	}
+
 	return p;
 }
 
 static void put_prev_task_dl(struct rq *rq, struct task_struct *p)
 {
 	update_curr_dl(rq);
+	update_dl_rq_load_avg(rq_clock_task(rq), cpu_of(rq), &rq->dl, 1);
 
 	if (on_dl_rq(&p->dl) && p->nr_cpus_allowed > 1)
 		enqueue_pushable_dl_task(rq, p);
@@ -1723,6 +1731,7 @@ static void put_prev_task_dl(struct rq *
 static void task_tick_dl(struct rq *rq, struct task_struct *p, int queued)
 {
 	update_curr_dl(rq);
+	update_dl_rq_load_avg(rq_clock_task(rq), cpu_of(rq), &rq->dl, 1);
 
 	/*
 	 * Even when we have runtime, update_curr_dl() might have resulted in us
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3017,6 +3017,11 @@ int update_rt_rq_load_avg(u64 now, int c
 	return ___update_load_avg(now, cpu, &rt_rq->avg, 0, running, NULL);
 }
 
+int update_dl_rq_load_avg(u64 now, int cpu, struct dl_rq *dl_rq, int running)
+{
+	return ___update_load_avg(now, cpu, &dl_rq->avg, 0, running, NULL);
+}
+
 
 /*
  * Signed add and clamp on underflow.
@@ -3550,6 +3555,11 @@ int update_rt_rq_load_avg(u64 now, int c
 	return 0;
 }
 
+int update_dl_rq_load_avg(u64 now, int cpu, struct dl_rq *dl_rq, int running)
+{
+	return 0;
+}
+
 #define UPDATE_TG	0x0
 #define SKIP_AGE_LOAD	0x0
 
@@ -6945,6 +6955,7 @@ static void update_blocked_averages(int
 	}
 
 	update_rt_rq_load_avg(rq_clock_task(rq), cpu, &rq->rt, 0);
+	update_dl_rq_load_avg(rq_clock_task(rq), cpu, &rq->dl, 0);
 	rq_unlock_irqrestore(rq, &rf);
 }
 
@@ -7005,6 +7016,7 @@ static inline void update_blocked_averag
 	update_rq_clock(rq);
 	update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq, true);
 	update_rt_rq_load_avg(rq_clock_task(rq), cpu, &rq->rt, 0);
+	update_dl_rq_load_avg(rq_clock_task(rq), cpu, &rq->dl, 0);
 	rq_unlock_irqrestore(rq, &rf);
 }
 
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -580,6 +580,8 @@ struct dl_rq {
 	 */
 	struct rb_root pushable_dl_tasks_root;
 	struct rb_node *pushable_dl_tasks_leftmost;
+
+	struct sched_avg avg;
 #else
 	struct dl_bw dl_bw;
 #endif