On 01-07-20, 10:07, Ionela Voinescu wrote:
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 83b58483a39b..60b5272c5d80 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -59,6 +59,9 @@ static struct cpufreq_driver *cpufreq_driver;
> static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
> static DEFINE_RWLOCK(cpufreq_driver_lock);
>
> +/* Mark support for the scheduler's frequency invariance engine */
> +static DEFINE_STATIC_KEY_FALSE(cpufreq_set_freq_scale);
> +
> /* Flag to suspend/resume CPUFreq governors */
> static bool cpufreq_suspended;
>
> @@ -67,6 +70,26 @@ static inline bool has_target(void)
> return cpufreq_driver->target_index || cpufreq_driver->target;
> }
>
> +static inline
> +void enable_cpufreq_freq_invariance(struct cpufreq_driver *driver)
> +{
> + if ((driver->flags & CPUFREQ_CUSTOM_SET_FREQ_SCALE) ||
> + ((driver->target_index || driver->fast_switch)
> + && !(driver->target || driver->setpolicy))) {
This will get simplified with the way I suggested it I believe.
> +
> + static_branch_enable_cpuslocked(&cpufreq_set_freq_scale);
> + pr_debug("%s: Driver %s can provide frequency invariance.",
> + __func__, driver->name);
> + } else
> + pr_err("%s: Driver %s cannot provide frequency invariance.",
> + __func__, driver->name);
> +}
> +
> +bool cpufreq_sets_freq_scale(void)
> +{
> + return static_branch_likely(&cpufreq_set_freq_scale);
> +}
> +
> /* internal prototypes */
> static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
> static int cpufreq_init_governor(struct cpufreq_policy *policy);
> @@ -2713,6 +2736,8 @@ int cpufreq_register_driver(struct cpufreq_driver
> *driver_data)
> cpufreq_driver = driver_data;
> write_unlock_irqrestore(&cpufreq_driver_lock, flags);
>
> + enable_cpufreq_freq_invariance(cpufreq_driver);
> +
> if (driver_data->setpolicy)
> driver_data->flags |= CPUFREQ_CONST_LOOPS;
>
> @@ -2782,6 +2807,7 @@ int cpufreq_unregister_driver(struct cpufreq_driver
> *driver)
> cpus_read_lock();
> subsys_interface_unregister(&cpufreq_interface);
> remove_boost_sysfs_file();
> + static_branch_disable_cpuslocked(&cpufreq_set_freq_scale);
> cpuhp_remove_state_nocalls_cpuslocked(hp_online);
>
> write_lock_irqsave(&cpufreq_driver_lock, flags);
> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
> index 42668588f9f8..8b6369d657bd 100644
> --- a/include/linux/cpufreq.h
> +++ b/include/linux/cpufreq.h
> @@ -217,6 +217,7 @@ void refresh_frequency_limits(struct cpufreq_policy
> *policy);
> void cpufreq_update_policy(unsigned int cpu);
> void cpufreq_update_limits(unsigned int cpu);
> bool have_governor_per_policy(void);
> +bool cpufreq_sets_freq_scale(void);
> struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
> void cpufreq_enable_fast_switch(struct cpufreq_policy *policy);
> void cpufreq_disable_fast_switch(struct cpufreq_policy *policy);
> @@ -237,6 +238,10 @@ static inline unsigned int
> cpufreq_get_hw_max_freq(unsigned int cpu)
> {
> return 0;
> }
> +static inline bool cpufreq_sets_freq_scale(void)
> +{
> + return false;
> +}
> static inline void disable_cpufreq(void) { }
> #endif
>
> --
> 2.17.1
--
viresh
