Re: [RFC 1/9] sched: cpufreq: add cpu to update_util_data

[Rafael J. Wysocki]

On Thursday, March 09, 2017 05:15:11 PM Viresh Kumar wrote:
> From: Steve Muckle <smuckle.linux@xxxxxxxxx>
> 
> Upcoming support for scheduler cpufreq callbacks on remote wakeups
> will require the client to know what the target CPU is that the
> callback is being invoked for. Add this information into the callback
> data structure.
> 
> Signed-off-by: Steve Muckle <smuckle.linux@xxxxxxxxx>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> ---
>  include/linux/sched/cpufreq.h | 1 +
>  kernel/sched/cpufreq.c        | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/include/linux/sched/cpufreq.h b/include/linux/sched/cpufreq.h
> index d2be2ccbb372..f798f63d93e8 100644
> --- a/include/linux/sched/cpufreq.h
> +++ b/include/linux/sched/cpufreq.h
> @@ -16,6 +16,7 @@
>  #ifdef CONFIG_CPU_FREQ
>  struct update_util_data {
>         void (*func)(struct update_util_data *data, u64 time, unsigned int flags);
> +	int cpu;

unsigned int?

>  };
>  
>  void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
> diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c
> index dbc51442ecbc..ee4c596b71b4 100644
> --- a/kernel/sched/cpufreq.c
> +++ b/kernel/sched/cpufreq.c
> @@ -42,6 +42,7 @@ void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
>  		return;
>  
>  	data->func = func;
> +	data->cpu = cpu;

But I'm not convinced that this helps at all.

>  	rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), data);
>  }
>  EXPORT_SYMBOL_GPL(cpufreq_add_update_util_hook);
> 

Thanks,
Rafael