On 06/06/13 04:40, Rafael J. Wysocki wrote:
> On Wednesday, June 05, 2013 08:52:52 AM Joe Jin wrote:
>> When _PPC changed dynamically the user_policy.max will not be updated,
>> this prevent CPU run on the highest frequency.
>
> Why should the user setting be always related to the current maximum available
> frequency? What if the user sets the limit for power capping purposes?
cpufreq_update_policy() get policy->max from user_policy.max:
1782 int cpufreq_update_policy(unsigned int cpu)
1783 {
[...]
1800 policy.min = data->user_policy.min;
1801 policy.max = data->user_policy.max;
1802 policy.policy = data->user_policy.policy;
1803 policy.governor = data->user_policy.governor;
[...]
1819 ret = __cpufreq_set_policy(data, &policy);
[...]
/sys/devices/system/cpu/cpu$/cpufreq/scaling_max_freq using policy->max
and user_policy->max, when update it, so I think _PPC changes also need
to update these two?
Thanks,
Joe
>
> Rafael
>
>
>> Signed-off-by: Joe Jin <joe....@oracle.com>
>> Cc: Rafael J. Wysocki <r...@sisk.pl>
>> Cc: Viresh Kumar <viresh.ku...@linaro.org>
>> ---
>> drivers/acpi/processor_perflib.c | 17 ++++++++++++++++-
>> 1 file changed, 16 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/acpi/processor_perflib.c
>> b/drivers/acpi/processor_perflib.c
>> index e854582..e01aa7d 100644
>> --- a/drivers/acpi/processor_perflib.c
>> +++ b/drivers/acpi/processor_perflib.c
>> @@ -180,6 +180,7 @@ static void acpi_processor_ppc_ost(acpi_handle handle,
>> int status)
>> int acpi_processor_ppc_has_changed(struct acpi_processor *pr, int
>> event_flag)
>> {
>> int ret;
>> + unsigned int saved = (unsigned int)pr->performance_platform_limit;
>>
>> if (ignore_ppc) {
>> /*
>> @@ -204,8 +205,22 @@ int acpi_processor_ppc_has_changed(struct
>> acpi_processor *pr, int event_flag)
>> }
>> if (ret < 0)
>> return (ret);
>> - else
>> + else {
>> + unsigned int ppc = (unsigned int)pr->performance_platform_limit;
>> +
>> + if (saved != ppc) {
>> + struct cpufreq_policy *policy;
>> +
>> + policy = cpufreq_cpu_get(pr->id);
>> + if (likely(policy))
>> + policy->user_policy.max =
>> + pr->performance->states[ppc].
>> + core_frequency * 1000;
>> + cpufreq_cpu_put(policy);
>> + }
>> +
>> return cpufreq_update_policy(pr->id);
>> + }
>> }
>>
>> int acpi_processor_get_bios_limit(int cpu, unsigned int *limit)
>>
--
Oracle <http://www.oracle.com>
Joe Jin | Software Development Senior Manager | +8610.6106.5624
ORACLE | Linux and Virtualization
No. 24 Zhongguancun Software Park, Haidian District | 100193 Beijing
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