Re: [RFC/RFT] [PATCH 06/10] cpufreq / sched: Add interface to get utilization values

From: Viresh Kumar
Date: Wed May 16 2018 - 02:08:16 EST


On 15-05-18, 21:49, Srinivas Pandruvada wrote:
> Added cpufreq_get_sched_util() to get the CFS, DL and max utilization
> values for a CPU. This is required for getting utilization values
> for cpufreq drivers outside of kernel/sched folder.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
> ---
> include/linux/sched/cpufreq.h | 2 ++
> kernel/sched/cpufreq.c | 23 +++++++++++++++++++++++
> 2 files changed, 25 insertions(+)
>
> diff --git a/include/linux/sched/cpufreq.h b/include/linux/sched/cpufreq.h
> index 5966744..a366600 100644
> --- a/include/linux/sched/cpufreq.h
> +++ b/include/linux/sched/cpufreq.h
> @@ -20,6 +20,8 @@ void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
> void (*func)(struct update_util_data *data, u64 time,
> unsigned int flags));
> void cpufreq_remove_update_util_hook(int cpu);
> +void cpufreq_get_sched_util(int cpu, unsigned long *util_cfs,
> + unsigned long *util_dl, unsigned long *max);
> #endif /* CONFIG_CPU_FREQ */
>
> #endif /* _LINUX_SCHED_CPUFREQ_H */
> diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c
> index 5e54cbc..36e2839 100644
> --- a/kernel/sched/cpufreq.c
> +++ b/kernel/sched/cpufreq.c
> @@ -60,3 +60,26 @@ void cpufreq_remove_update_util_hook(int cpu)
> rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL);
> }
> EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook);
> +
> +/**
> + * cpufreq_get_sched_util - Get utilization values.
> + * @cpu: The targeted CPU.
> + *
> + * Get the CFS, DL and max utilization.
> + * This function allows cpufreq driver outside the kernel/sched to access
> + * utilization value for a CPUs run queue.
> + */
> +void cpufreq_get_sched_util(int cpu, unsigned long *util_cfs,
> + unsigned long *util_dl, unsigned long *max)
> +{
> +#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL

What will happen when schedutil is compiled in the kernel but ondemand
is the one getting used currently ?

> + struct rq *rq = cpu_rq(cpu);
> +
> + *max = arch_scale_cpu_capacity(NULL, cpu);
> + *util_cfs = cpu_util_cfs(rq);
> + *util_dl = cpu_util_dl(rq);
> +#else
> + *util_cfs = *util_dl = 1;
> +#endif
> +}
> +EXPORT_SYMBOL_GPL(cpufreq_get_sched_util);
> --
> 2.9.5

--
viresh