[RFC PATCH v3 2/6] sched/cpufreq: Attach perf domain to sugov policy

[Douglas RAILLARD <douglas.raillard@arm.com>]

Attach an Energy Model perf_domain to each sugov_policy to prepare the
ground for energy-aware schedutil.

Signed-off-by: Douglas RAILLARD <douglas.raillard@arm.com>
---
 kernel/sched/cpufreq_schedutil.c | 39 ++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index ba9e8309eec7..9abda58827c0 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -42,6 +42,10 @@ struct sugov_policy {
 
 	bool			limits_changed;
 	bool			need_freq_update;
+
+#ifdef CONFIG_ENERGY_MODEL
+	struct em_perf_domain *pd;
+#endif
 };
 
 struct sugov_cpu {
@@ -66,6 +70,38 @@ static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu);
 
 /************************ Governor internals ***********************/
 
+#ifdef CONFIG_ENERGY_MODEL
+static void sugov_policy_attach_pd(struct sugov_policy *sg_policy)
+{
+	struct em_perf_domain *pd;
+	struct cpufreq_policy *policy = sg_policy->policy;
+
+	sg_policy->pd = NULL;
+	pd = em_cpu_get(policy->cpu);
+	if (!pd)
+		return;
+
+	if (cpumask_equal(policy->related_cpus, to_cpumask(pd->cpus)))
+		sg_policy->pd = pd;
+	else
+		pr_warn("%s: Not all CPUs in schedutil policy %u share the same perf domain, no perf domain for that policy will be registered\n",
+			__func__, policy->cpu);
+}
+
+static struct em_perf_domain *sugov_policy_get_pd(
+						struct sugov_policy *sg_policy)
+{
+	return sg_policy->pd;
+}
+#else /* CONFIG_ENERGY_MODEL */
+static void sugov_policy_attach_pd(struct sugov_policy *sg_policy) {}
+static struct em_perf_domain *sugov_policy_get_pd(
+						struct sugov_policy *sg_policy)
+{
+	return NULL;
+}
+#endif /* CONFIG_ENERGY_MODEL */
+
 static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time)
 {
 	s64 delta_ns;
@@ -859,6 +895,9 @@ static int sugov_start(struct cpufreq_policy *policy)
 							sugov_update_shared :
 							sugov_update_single);
 	}
+
+	sugov_policy_attach_pd(sg_policy);
+
 	return 0;
 }
 
-- 
2.23.0