Re: [PATCH V2] cpufreq: drivers with target_index() must set freq_table

[Rafael J. Wysocki]

On Tue, Apr 4, 2023 at 1:39 AM Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
>
> Since the cpufreq core directly uses freq_table, for cpufreq drivers
> that set their target_index() callback, make it mandatory for them to
> set the same.
>
> Since this is set per policy and normally from policy->init(), do this
> from cpufreq_table_validate_and_sort() which gets called right after
> ->init().
>
> Reported-by: Yajun Deng <yajun.deng@xxxxxxxxx>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> ---
> V2: Move declaration to cpufreq.h.
>
>  drivers/cpufreq/cpufreq.c    | 5 +++++
>  drivers/cpufreq/freq_table.c | 7 ++++++-
>  include/linux/cpufreq.h      | 1 +
>  3 files changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 6d8fd3b8dcb5..09131c54703f 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -73,6 +73,11 @@ static inline bool has_target(void)
>         return cpufreq_driver->target_index || cpufreq_driver->target;
>  }
>
> +bool has_target_index(void)
> +{
> +       return !!cpufreq_driver->target_index;
> +}
> +
>  /* internal prototypes */
>  static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
>  static int cpufreq_init_governor(struct cpufreq_policy *policy);
> diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
> index 90bfc27ed1ba..c4d4643b6ca6 100644
> --- a/drivers/cpufreq/freq_table.c
> +++ b/drivers/cpufreq/freq_table.c
> @@ -355,8 +355,13 @@ int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy)
>  {
>         int ret;
>
> -       if (!policy->freq_table)
> +       if (!policy->freq_table) {
> +               /* Freq table must be passed by drivers with target_index() */
> +               if (has_target_index())
> +                       return -EINVAL;
> +
>                 return 0;
> +       }
>
>         ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table);
>         if (ret)
> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
> index 65623233ab2f..541013487a0e 100644
> --- a/include/linux/cpufreq.h
> +++ b/include/linux/cpufreq.h
> @@ -237,6 +237,7 @@ bool cpufreq_supports_freq_invariance(void);
>  struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
>  void cpufreq_enable_fast_switch(struct cpufreq_policy *policy);
>  void cpufreq_disable_fast_switch(struct cpufreq_policy *policy);
> +bool has_target_index(void);
>  #else
>  static inline unsigned int cpufreq_get(unsigned int cpu)
>  {
> --

Applied as 6.4 material, thanks!