[PATCH 3/3] powercap/drivers/idle_inject: Specify the idle state to inject

[Daniel Lezcano]

Currently the idle injection framework only allows to inject the
deepest idle state available on the system.

Give the opportunity to specify which idle state we want to inject by
adding a new function helper to set the state and use it when calling
play_idle().

Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
 drivers/powercap/idle_inject.c | 15 ++++++++++++++-
 include/linux/idle_inject.h    |  3 +++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/powercap/idle_inject.c b/drivers/powercap/idle_inject.c
index 9b18667b9f26..a94ebab9ee21 100644
--- a/drivers/powercap/idle_inject.c
+++ b/drivers/powercap/idle_inject.c
@@ -38,6 +38,7 @@
 #define pr_fmt(fmt) "ii_dev: " fmt
 
 #include <linux/cpu.h>
+#include <linux/cpuidle.h>
 #include <linux/hrtimer.h>
 #include <linux/kthread.h>
 #include <linux/sched.h>
@@ -65,6 +66,7 @@ struct idle_inject_thread {
  */
 struct idle_inject_device {
 	struct hrtimer timer;
+	int state;
 	unsigned int idle_duration_us;
 	unsigned int run_duration_us;
 	unsigned long int cpumask[0];
@@ -139,7 +141,7 @@ static void idle_inject_fn(unsigned int cpu)
 	iit->should_run = 0;
 
 	play_idle(READ_ONCE(ii_dev->idle_duration_us),
-		  cpuidle_find_deepest_state());
+		  READ_ONCE(ii_dev->state));
 }
 
 /**
@@ -170,6 +172,16 @@ void idle_inject_get_duration(struct idle_inject_device *ii_dev,
 	*idle_duration_us = READ_ONCE(ii_dev->idle_duration_us);
 }
 
+/**
+ * idle_inject_set_state - set the idle state to inject
+ * @state: an integer for the idle state to inject
+ */
+void idle_inject_set_state(struct idle_inject_device *ii_dev, int state)
+{
+	if (state >= -1 && state < CPUIDLE_STATE_MAX)
+		WRITE_ONCE(ii_dev->state, state);
+}
+
 /**
  * idle_inject_start - start idle injections
  * @ii_dev: idle injection control device structure
@@ -298,6 +310,7 @@ struct idle_inject_device *idle_inject_register(struct cpumask *cpumask)
 	cpumask_copy(to_cpumask(ii_dev->cpumask), cpumask);
 	hrtimer_init(&ii_dev->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	ii_dev->timer.function = idle_inject_timer_fn;
+	ii_dev->state = cpuidle_find_deepest_state();
 
 	for_each_cpu(cpu, to_cpumask(ii_dev->cpumask)) {
 
diff --git a/include/linux/idle_inject.h b/include/linux/idle_inject.h
index a445cd1a36c5..e2b26b9ccd34 100644
--- a/include/linux/idle_inject.h
+++ b/include/linux/idle_inject.h
@@ -26,4 +26,7 @@ void idle_inject_set_duration(struct idle_inject_device *ii_dev,
 void idle_inject_get_duration(struct idle_inject_device *ii_dev,
 				 unsigned int *run_duration_us,
 				 unsigned int *idle_duration_us);
+
+void idle_inject_set_state(struct idle_inject_device *ii_dev, int state);
+
 #endif /* __IDLE_INJECT_H__ */
-- 
2.17.1