Re: [PATCH v3] cpufreq: ondemand: handle SW coordinated CPUs

From: Fabio Baltieri
Date: Thu Nov 22 2012 - 13:38:52 EST


Hello Rafael,

thanks for the review! I only have one concern before sending a v4:

On Thu, Nov 22, 2012 at 01:10:15AM +0100, Rafael J. Wysocki wrote:
> > @@ -627,32 +659,41 @@ static void do_dbs_timer(struct work_struct *work)
> > delay -= jiffies % delay;
> > }
> > } else {
> > - __cpufreq_driver_target(dbs_info->cur_policy,
> > - dbs_info->freq_lo, CPUFREQ_RELATION_H);
> > + if (sample)
> > + __cpufreq_driver_target(dbs_info->cur_policy,
> > + dbs_info->freq_lo,
> > + CPUFREQ_RELATION_H);
> > delay = dbs_info->freq_lo_jiffies;
> > }
> > - schedule_delayed_work_on(cpu, &dbs_info->work, delay);
> > + schedule_delayed_work_on(smp_processor_id(), dw, delay);
>
> We're not supposed to be using smp_processor_id() any more.
> get_cpu()/put_cpu() should be used instead.

That's going to add preemption protection, do I need that? The function
is called from a kworker with the affinity set on a specific CPU, so it
should not migrate to a different one during execution.

I agree with you for all the other comments.

Thanks,
Fabio

--
Fabio Baltieri
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