Re: [PATCH V5 2/3] cpuidle: play_idle: Specify play_idle with an idle state

From: Ulf Hansson
Date: Mon Oct 28 2019 - 18:26:46 EST


On Mon, 28 Oct 2019 at 15:34, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> wrote:
>
> Currently, the play_idle function does not allow to tell which idle
> state we want to go. Improve this by passing the idle state as
> parameter to the function.
>
> Export cpuidle_find_deepest_state() symbol as it is used from the
> intel_powerclamp driver as a module.
>
> There is no functional changes, the cpuidle state is the deepest one.
>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> Acked-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>

Kind regards
Uffe



> ---
> V4:
> - Add EXPORT_SYMBOL_GPL(cpuidle_find_deepest_state) for the
> intel_powerclamp driver when this one is compiled as a module
> V3:
> - Add missing cpuidle.h header
> ---
> drivers/cpuidle/cpuidle.c | 1 +
> drivers/powercap/idle_inject.c | 4 +++-
> drivers/thermal/intel/intel_powerclamp.c | 4 +++-
> include/linux/cpu.h | 2 +-
> kernel/sched/idle.c | 4 ++--
> 5 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
> index f8b54f277589..94804e532b9a 100644
> --- a/drivers/cpuidle/cpuidle.c
> +++ b/drivers/cpuidle/cpuidle.c
> @@ -126,6 +126,7 @@ int cpuidle_find_deepest_state(void)
>
> return find_deepest_state(drv, dev, UINT_MAX, 0, false);
> }
> +EXPORT_SYMBOL_GPL(cpuidle_find_deepest_state);
>
> #ifdef CONFIG_SUSPEND
> static void enter_s2idle_proper(struct cpuidle_driver *drv,
> diff --git a/drivers/powercap/idle_inject.c b/drivers/powercap/idle_inject.c
> index cd1270614cc6..233c878cbf46 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>
> @@ -138,7 +139,8 @@ static void idle_inject_fn(unsigned int cpu)
> */
> iit->should_run = 0;
>
> - play_idle(READ_ONCE(ii_dev->idle_duration_us));
> + play_idle(READ_ONCE(ii_dev->idle_duration_us),
> + cpuidle_find_deepest_state());
> }
>
> /**
> diff --git a/drivers/thermal/intel/intel_powerclamp.c b/drivers/thermal/intel/intel_powerclamp.c
> index 53216dcbe173..b55786c169ae 100644
> --- a/drivers/thermal/intel/intel_powerclamp.c
> +++ b/drivers/thermal/intel/intel_powerclamp.c
> @@ -29,6 +29,7 @@
> #include <linux/delay.h>
> #include <linux/kthread.h>
> #include <linux/cpu.h>
> +#include <linux/cpuidle.h>
> #include <linux/thermal.h>
> #include <linux/slab.h>
> #include <linux/tick.h>
> @@ -430,7 +431,8 @@ static void clamp_idle_injection_func(struct kthread_work *work)
> if (should_skip)
> goto balance;
>
> - play_idle(jiffies_to_usecs(w_data->duration_jiffies));
> + play_idle(jiffies_to_usecs(w_data->duration_jiffies),
> + cpuidle_find_deepest_state());
>
> balance:
> if (clamping && w_data->clamping && cpu_online(w_data->cpu))
> diff --git a/include/linux/cpu.h b/include/linux/cpu.h
> index d0633ebdaa9c..23478208fc55 100644
> --- a/include/linux/cpu.h
> +++ b/include/linux/cpu.h
> @@ -179,7 +179,7 @@ void arch_cpu_idle_dead(void);
> int cpu_report_state(int cpu);
> int cpu_check_up_prepare(int cpu);
> void cpu_set_state_online(int cpu);
> -void play_idle(unsigned long duration_us);
> +void play_idle(unsigned long duration_us, int state);
>
> #ifdef CONFIG_HOTPLUG_CPU
> bool cpu_wait_death(unsigned int cpu, int seconds);
> diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
> index fc7f5216b579..af90abe0c1b3 100644
> --- a/kernel/sched/idle.c
> +++ b/kernel/sched/idle.c
> @@ -314,7 +314,7 @@ static enum hrtimer_restart idle_inject_timer_fn(struct hrtimer *timer)
> return HRTIMER_NORESTART;
> }
>
> -void play_idle(unsigned long duration_us)
> +void play_idle(unsigned long duration_us, int state)
> {
> struct idle_timer it;
>
> @@ -331,7 +331,7 @@ void play_idle(unsigned long duration_us)
> rcu_sleep_check();
> preempt_disable();
> current->flags |= PF_IDLE;
> - cpuidle_use_state(cpuidle_find_deepest_state());
> + cpuidle_use_state(state);
>
> it.done = 0;
> hrtimer_init_on_stack(&it.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
> --
> 2.17.1
>