sched/dl: Add dl_rq utilization tracking

Similarly to what happens with RT tasks, CFS tasks can be preempted by DL
tasks and the CFS's utilization might no longer describes the real
utilization level.

Current DL bandwidth reflects the requirements to meet deadline when tasks are
enqueued but not the current utilization of the DL sched class. We track
DL class utilization to estimate the system utilization.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: claudio@evidence.eu.com
Cc: daniel.lezcano@linaro.org
Cc: dietmar.eggemann@arm.com
Cc: joel@joelfernandes.org
Cc: juri.lelli@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: patrick.bellasi@arm.com
Cc: quentin.perret@arm.com
Cc: rjw@rjwysocki.net
Cc: valentin.schneider@arm.com
Cc: viresh.kumar@linaro.org
Link: http://lkml.kernel.org/r/1530200714-4504-5-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 8 insertions, 3 deletions

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 5b453213cd18..f096275c7df2 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7290,11 +7290,14 @@ static inline bool cfs_rq_has_blocked(struct cfs_rq *cfs_rq)
 	return false;
 }
 
-static inline bool rt_rq_has_blocked(struct rq *rq)
+static inline bool others_rqs_have_blocked(struct rq *rq)
 {
 	if (READ_ONCE(rq->avg_rt.util_avg))
 		return true;
 
+	if (READ_ONCE(rq->avg_dl.util_avg))
+		return true;
+
 	return false;
 }
 
@@ -7358,8 +7361,9 @@ static void update_blocked_averages(int cpu)
 			done = false;
 	}
 	update_rt_rq_load_avg(rq_clock_task(rq), rq, 0);
+	update_dl_rq_load_avg(rq_clock_task(rq), rq, 0);
 	/* Don't need periodic decay once load/util_avg are null */
-	if (rt_rq_has_blocked(rq))
+	if (others_rqs_have_blocked(rq))
 		done = false;
 
 #ifdef CONFIG_NO_HZ_COMMON
@@ -7427,9 +7431,10 @@ static inline void update_blocked_averages(int cpu)
 	update_rq_clock(rq);
 	update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq);
 	update_rt_rq_load_avg(rq_clock_task(rq), rq, 0);
+	update_dl_rq_load_avg(rq_clock_task(rq), rq, 0);
 #ifdef CONFIG_NO_HZ_COMMON
 	rq->last_blocked_load_update_tick = jiffies;
-	if (!cfs_rq_has_blocked(cfs_rq) && !rt_rq_has_blocked(rq))
+	if (!cfs_rq_has_blocked(cfs_rq) && !others_rqs_have_blocked(rq))
 		rq->has_blocked_load = 0;
 #endif
 	rq_unlock_irqrestore(rq, &rf);