[RFC PATCH v3 2/5] cpuidle: Add Cpufreq Active Stats calls tracking idle entry/exit

From: Lukasz Luba
Date: Wed Apr 06 2022 - 18:08:37 EST


The Cpufreq Active Stats tracks and accounts the activity of the CPU
for each performance level. It accounts the real residency, when the CPU
was not idle, at a given performance level. This patch adds needed calls
which provide the CPU idle entry/exit events to the Cpufreq Active Stats.

Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>
---
drivers/cpuidle/cpuidle.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index ef2ea1b12cd8..f19711b95afb 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -16,6 +16,7 @@
#include <linux/notifier.h>
#include <linux/pm_qos.h>
#include <linux/cpu.h>
+#include <linux/cpufreq_stats.h>
#include <linux/cpuidle.h>
#include <linux/ktime.h>
#include <linux/hrtimer.h>
@@ -231,6 +232,8 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
trace_cpu_idle(index, dev->cpu);
time_start = ns_to_ktime(local_clock());

+ cpufreq_active_stats_cpu_idle_enter(time_start);
+
stop_critical_timings();
if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
rcu_idle_enter();
@@ -243,6 +246,8 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
time_end = ns_to_ktime(local_clock());
trace_cpu_idle(PWR_EVENT_EXIT, dev->cpu);

+ cpufreq_active_stats_cpu_idle_exit(time_end);
+
/* The cpu is no longer idle or about to enter idle. */
sched_idle_set_state(NULL);

--
2.17.1