[PATCH v5 03/10] cpufreq/schedutil: add rt utilization tracking

From: Vincent Guittot
Date: Fri May 25 2018 - 09:13:36 EST


Add both cfs and rt utilization when selecting an OPP for cfs tasks as rt
can preempt and steal cfs's running time.

Signed-off-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
---
kernel/sched/cpufreq_schedutil.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 28592b6..a84b5a5 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -56,6 +56,7 @@ struct sugov_cpu {
/* The fields below are only needed when sharing a policy: */
unsigned long util_cfs;
unsigned long util_dl;
+ unsigned long util_rt;
unsigned long max;

/* The field below is for single-CPU policies only: */
@@ -178,14 +179,21 @@ static void sugov_get_util(struct sugov_cpu *sg_cpu)
sg_cpu->max = arch_scale_cpu_capacity(NULL, sg_cpu->cpu);
sg_cpu->util_cfs = cpu_util_cfs(rq);
sg_cpu->util_dl = cpu_util_dl(rq);
+ sg_cpu->util_rt = cpu_util_rt(rq);
}

static unsigned long sugov_aggregate_util(struct sugov_cpu *sg_cpu)
{
struct rq *rq = cpu_rq(sg_cpu->cpu);
+ unsigned long util;

- if (rq->rt.rt_nr_running)
- return sg_cpu->max;
+ if (rq->rt.rt_nr_running) {
+ util = sg_cpu->max;
+ } else {
+ util = sg_cpu->util_dl;
+ util += sg_cpu->util_cfs;
+ util += sg_cpu->util_rt;
+ }

/*
* Utilization required by DEADLINE must always be granted while, for
@@ -197,7 +205,7 @@ static unsigned long sugov_aggregate_util(struct sugov_cpu *sg_cpu)
* util_cfs + util_dl as requested freq. However, cpufreq is not yet
* ready for such an interface. So, we only do the latter for now.
*/
- return min(sg_cpu->max, (sg_cpu->util_dl + sg_cpu->util_cfs));
+ return min(sg_cpu->max, util);
}

static void sugov_set_iowait_boost(struct sugov_cpu *sg_cpu, u64 time, unsigned int flags)
--
2.7.4