Re: [PATCH 1/5] cpufreq: Use cpumask_copy instead of cpumask_or to copy a mask

From: Viresh Kumar
Date: Mon Oct 12 2015 - 23:23:27 EST


On 12-10-15, 12:12, Saravana Kannan wrote:
> > if (new_policy) {
> > /* related_cpus should at least include policy->cpus. */
> >- cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);
> >+ cpumask_copy(policy->related_cpus, policy->cpus);
>
> Again, why? It actually seems wrong. A 4 core cluster could come up
> with just 2 cores when the policy is added. But the related CPUs
> would be 4 CPUs.

Firstly, the patch hasn't changed anything at all. related_cpus was
empty until this point, and orring or setting it with ->cpus will
result in the same output.

Secondly, this is what we always wanted. related_cpus should contain
the mask of all possible CPUs for that cluster.

--
viresh
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