[RFC/RFT] [PATCH 06/10] cpufreq / sched: Add interface to get utilization values

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

Added cpufreq_get_sched_util() to get the CFS, DL and max utilization
values for a CPU. This is required for getting utilization values
for cpufreq drivers outside of kernel/sched folder.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 include/linux/sched/cpufreq.h |  2 ++
 kernel/sched/cpufreq.c        | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/include/linux/sched/cpufreq.h b/include/linux/sched/cpufreq.h
index 5966744..a366600 100644
--- a/include/linux/sched/cpufreq.h
+++ b/include/linux/sched/cpufreq.h
@@ -20,6 +20,8 @@ void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
                        void (*func)(struct update_util_data *data, u64 time,
 				    unsigned int flags));
 void cpufreq_remove_update_util_hook(int cpu);
+void cpufreq_get_sched_util(int cpu, unsigned long *util_cfs,
+			    unsigned long *util_dl, unsigned long *max);
 #endif /* CONFIG_CPU_FREQ */
 
 #endif /* _LINUX_SCHED_CPUFREQ_H */
diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c
index 5e54cbc..36e2839 100644
--- a/kernel/sched/cpufreq.c
+++ b/kernel/sched/cpufreq.c
@@ -60,3 +60,26 @@ void cpufreq_remove_update_util_hook(int cpu)
 	rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL);
 }
 EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook);
+
+/**
+ * cpufreq_get_sched_util - Get utilization values.
+ * @cpu: The targeted CPU.
+ *
+ * Get the CFS, DL and max utilization.
+ * This function allows cpufreq driver outside the kernel/sched to access
+ * utilization value for a CPUs run queue.
+ */
+void cpufreq_get_sched_util(int cpu, unsigned long *util_cfs,
+			    unsigned long *util_dl, unsigned long *max)
+{
+#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
+	struct rq *rq = cpu_rq(cpu);
+
+	*max = arch_scale_cpu_capacity(NULL, cpu);
+	*util_cfs = cpu_util_cfs(rq);
+	*util_dl  = cpu_util_dl(rq);
+#else
+	*util_cfs = *util_dl = 1;
+#endif
+}
+EXPORT_SYMBOL_GPL(cpufreq_get_sched_util);
-- 
2.9.5