sched/core: Add API to set cluster d-state

Add new API to the scheduler to allow low power mode driver to inform
the scheduler about the d-state of a cluster. This can be leveraged by
the scheduler to make an informed decision about the cost of placing a task
on a cluster.

Change-Id: If0fe0fdba7acad1c2eb73654ebccfdb421225e62
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
[joonwoop@codeaurora.org: omitted fixes for qhmp_core.c and qhmp_core.h]
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index cc3ba6ee00d8..1150d8665ac8 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -787,6 +787,29 @@ sched_set_cpu_cstate(int cpu, int cstate, int wakeup_energy, int wakeup_latency)
 	rq->wakeup_energy = wakeup_energy;
 	rq->wakeup_latency = wakeup_latency;
 }
+
+/*
+ * Note D-state for (idle) cluster.
+ *
+ * @dstate = dstate index, 0 -> active state
+ * @wakeup_energy = energy spent in waking up cluster
+ * @wakeup_latency = latency to wakeup from cluster
+ *
+ */
+void sched_set_cluster_dstate(const cpumask_t *cluster_cpus, int dstate,
+			int wakeup_energy, int wakeup_latency)
+{
+	int cpu;
+
+	for_each_cpu(cpu, cluster_cpus) {
+		struct rq *rq = cpu_rq(cpu);
+
+		rq->dstate = dstate;
+		rq->dstate_wakeup_energy = wakeup_energy;
+		rq->dstate_wakeup_latency = wakeup_latency;
+	}
+}
+
 #endif /* CONFIG_SMP */
 
 #if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \
@@ -9385,6 +9408,10 @@ void __init sched_init(void)
 		rq->cstate = 0;
 		rq->wakeup_latency = 0;
 
+		rq->dstate = 0;
+		rq->dstate_wakeup_latency = 0;
+		rq->dstate_wakeup_energy = 0;
+
 		INIT_LIST_HEAD(&rq->cfs_tasks);
 
 		rq_attach_root(rq, &def_root_domain);