linux-kernel - Re: [PATCH v1 06/10] cpufreq: Use locking guard and __free() in cpufreq_update

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Message-ID: <20250401084625.345sbknbhslzagzu@vireshk-i7>
Date: Tue, 1 Apr 2025 14:16:25 +0530
From: Viresh Kumar <viresh.kumar@...aro.org>
To: "Rafael J. Wysocki" <rjw@...ysocki.net>
Cc: Linux PM <linux-pm@...r.kernel.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
	Mario Limonciello <mario.limonciello@....com>,
	Sudeep Holla <sudeep.holla@....com>
Subject: Re: [PATCH v1 06/10] cpufreq: Use locking guard and __free() in
 cpufreq_update_policy()

On 28-03-25, 21:44, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
> 
> Instead of using cpufreq_cpu_acquire() and cpufreq_cpu_release() in
> cpufreq_update_policy(), which is the last user of these functions,
> make it use __free() for policy reference counting cleanup and the
> "write" locking guard for policy locking.
> 
> No intentional functional impact.
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
> ---
>  drivers/cpufreq/cpufreq.c |   10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -2752,23 +2752,23 @@
>   */
>  void cpufreq_update_policy(unsigned int cpu)
>  {
> -	struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu);
> +	struct cpufreq_policy *policy __free(put_cpufreq_policy);
>  
> +	policy = cpufreq_cpu_get(cpu);
>  	if (!policy)
>  		return;
>  
> +	guard(cpufreq_policy_write)(policy);
> +
>  	/*
>  	 * BIOS might change freq behind our back
>  	 * -> ask driver for current freq and notify governors about a change
>  	 */
>  	if (cpufreq_driver->get && has_target() &&
>  	    (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false))))
> -		goto unlock;
> +		return;
>  
>  	refresh_frequency_limits(policy);
> -
> -unlock:
> -	cpufreq_cpu_release(policy);

Acked-by: Viresh Kumar <viresh.kumar@...aro.org>

-- 
viresh