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

From: Mathieu Poirier
Date: Wed Sep 18 2019 - 15:36:00 EST


On Mon, Sep 09, 2019 at 04:50:15PM +0200, Daniel Lezcano wrote:
> 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().
>
> There is no functional changes, the cpuidle state is the deepest one.
>
> 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..a612c425d74c 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 >= CPUIDLE_STATE_NOUSE && 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);
> +

The above function is not used in this patch and as such should be introduce as
part of future work. Otherwise I agree that this patch does not carry any
functional changes.

Without function idle_inject_set_state():

Acked-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

> #endif /* __IDLE_INJECT_H__ */
> --
> 2.17.1
>