Re: [PATCH v2 1/3] cpufreq: CPPC: Add cppc_cpufreq_search_cpu_data

[Pierre Gondois <pierre.gondois@arm.com>]

On 4/11/22 05:10, Viresh Kumar wrote:
> On 07-04-22, 10:16, Pierre Gondois wrote:
>> From: Pierre Gondois <Pierre.Gondois@arm.com>
>>
>> cppc_cpufreq_get_cpu_data() allocates a new struct cppc_cpudata
>> for the input CPU at each call.
>>
>> To search the struct associated with a cpu without allocating
>> a new one, add cppc_cpufreq_search_cpu_data().
>> Also add an early prototype.
>>
>> This will be used in a later patch, when generating artificial
>> performance states to register an artificial Energy Model in the
>> cppc_cpufreq driver and enable the Energy Aware Scheduler for ACPI
>> based systems.
>>
>> Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
>> ---
>>   drivers/cpufreq/cppc_cpufreq.c | 15 +++++++++++++++
>>   1 file changed, 15 insertions(+)
>>
>> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
>> index 82d370ae6a4a..ffcd9704add2 100644
>> --- a/drivers/cpufreq/cppc_cpufreq.c
>> +++ b/drivers/cpufreq/cppc_cpufreq.c
>> @@ -41,6 +41,8 @@
>>    */
>>   static LIST_HEAD(cpu_data_list);
>>   
>> +static struct cppc_cpudata *cppc_cpufreq_search_cpu_data(unsigned int cpu);
>> +
>>   static bool boost_supported;
>>   
>>   struct cppc_workaround_oem_info {
>> @@ -479,6 +481,19 @@ static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)
>>   	policy->driver_data = NULL;
>>   }
>>   
>> +static struct cppc_cpudata *
>> +cppc_cpufreq_search_cpu_data(unsigned int cpu)
>> +{
>> +	struct cppc_cpudata *iter, *tmp;
>> +
>> +	list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) {
>> +		if (cpumask_test_cpu(cpu, iter->shared_cpu_map))
>> +			return iter;
>> +	}
>> +
>> +	return NULL;
>> +}
> 
> Did you miss this in cppc_cpufreq_cpu_init() ?
> 
> 	policy->driver_data = cpu_data;
> 
> The data is saved inside the policy and it shouldn't be difficult to
> fetch it from there, instead of going through the list.
> 

A previous (internal) implementation required this function,
but this is not necessary anymore indeed. I will drop this patch,
Thanks for the review,
Pierre