Re: [PATCH] cpufreq: pass policy to ->get() driver callback

From: Viresh Kumar
Date: Fri Sep 11 2015 - 12:18:15 EST


On 10-09-15, 23:36, Rafael J. Wysocki wrote:
> BTW, I wonder how much of the stuff in cpufreq.h can be moved to a local header
> under drivers/cpufreq/. It looks like the majority of it is not used by
> anybody else.

Okay, will check that out and do some cleanup.

> ---
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> Subject: cpufreq: acpi-cpufreq: Use cpufreq_cpu_get_raw() in ->get()
>
> cpufreq_cpu_get() called by get_cur_freq_on_cpu() is overkill,
> because the ->get() callback is always invoked in a context in
> which all of the conditions checked by cpufreq_cpu_get() are
> guaranteed to be satisfied.
>
> Use cpufreq_cpu_get_raw() instead of it and drop the
> corresponding cpufreq_cpu_put() from get_cur_freq_on_cpu().
>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
> drivers/cpufreq/acpi-cpufreq.c | 3 +--
> drivers/cpufreq/cpufreq.c | 2 +-
> include/linux/cpufreq.h | 5 +++++
> 3 files changed, 7 insertions(+), 3 deletions(-)
>
> Index: linux-pm/drivers/cpufreq/acpi-cpufreq.c
> ===================================================================
> --- linux-pm.orig/drivers/cpufreq/acpi-cpufreq.c
> +++ linux-pm/drivers/cpufreq/acpi-cpufreq.c
> @@ -375,12 +375,11 @@ static unsigned int get_cur_freq_on_cpu(
>
> pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
>
> - policy = cpufreq_cpu_get(cpu);
> + policy = cpufreq_cpu_get_raw(cpu);
> if (unlikely(!policy))
> return 0;
>
> data = policy->driver_data;
> - cpufreq_cpu_put(policy);
> if (unlikely(!data || !data->freq_table))
> return 0;
>
> Index: linux-pm/drivers/cpufreq/cpufreq.c
> ===================================================================
> --- linux-pm.orig/drivers/cpufreq/cpufreq.c
> +++ linux-pm/drivers/cpufreq/cpufreq.c
> @@ -238,13 +238,13 @@ int cpufreq_generic_init(struct cpufreq_
> }
> EXPORT_SYMBOL_GPL(cpufreq_generic_init);
>
> -/* Only for cpufreq core internal use */
> struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
> {
> struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
>
> return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL;
> }
> +EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw);
>
> unsigned int cpufreq_generic_get(unsigned int cpu)
> {
> Index: linux-pm/include/linux/cpufreq.h
> ===================================================================
> --- linux-pm.orig/include/linux/cpufreq.h
> +++ linux-pm/include/linux/cpufreq.h
> @@ -129,9 +129,14 @@ struct cpufreq_policy {
> #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/
>
> #ifdef CONFIG_CPU_FREQ
> +struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu);
> struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu);
> void cpufreq_cpu_put(struct cpufreq_policy *policy);
> #else
> +static inline struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
> +{
> + return NULL;
> +}
> static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
> {
> return NULL;

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

--
viresh
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