linux-kernel - Re: [PATCH v1 2/7] powercap/dtpm_cpu: Reset per

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Date:   Wed, 16 Feb 2022 17:24:35 +0100
From:   Ulf Hansson <ulf.hansson@...aro.org>
To:     Daniel Lezcano <daniel.lezcano@...aro.org>
Cc:     rjw@...ysocki.net, heiko@...ech.de, lukasz.luba@....com,
        linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        Daniel Lezcano <daniel.lezcano@...nel.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>
Subject: Re: [PATCH v1 2/7] powercap/dtpm_cpu: Reset per_cpu variable in the
 release function

On Sun, 30 Jan 2022 at 22:02, Daniel Lezcano <daniel.lezcano@...aro.org> wrote:
>
> The release function does not reset the per cpu variable when it is
> called. That will prevent creation again as the variable will be
> already from the previous creation.
>
> Fix it by resetting them.
>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>

Reviewed-by: Ulf Hansson <ulf.hansson@...aro.org>

Kind regards
Uffe


> ---
>  drivers/powercap/dtpm_cpu.c | 7 +++++++
>  1 file changed, 7 insertions(+)
>
> diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c
> index eed5ad688d46..71f45d2f5a60 100644
> --- a/drivers/powercap/dtpm_cpu.c
> +++ b/drivers/powercap/dtpm_cpu.c
> @@ -151,10 +151,17 @@ static int update_pd_power_uw(struct dtpm *dtpm)
>  static void pd_release(struct dtpm *dtpm)
>  {
>         struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm);
> +       struct cpufreq_policy *policy;
>
>         if (freq_qos_request_active(&dtpm_cpu->qos_req))
>                 freq_qos_remove_request(&dtpm_cpu->qos_req);
>
> +       policy = cpufreq_cpu_get(dtpm_cpu->cpu);
> +       if (policy) {
> +               for_each_cpu(dtpm_cpu->cpu, policy->related_cpus)
> +                       per_cpu(dtpm_per_cpu, dtpm_cpu->cpu) = NULL;
> +       }
> +
>         kfree(dtpm_cpu);
>  }
>
> --
> 2.25.1
>