Re: [PATCH 5/7] cpufreq: balance out cpufreq_cpu_{get,put} forscaling drivers using setpolicy

From: Viresh Kumar
Date: Tue Feb 05 2013 - 21:45:36 EST


On 6 February 2013 07:38, Dirk Brandewie <dirk.brandewie@xxxxxxxxx> wrote:
> On 02/05/2013 05:58 PM, Viresh Kumar wrote:
>>
>> On Tue, Feb 5, 2013 at 11:54 PM, <dirk.brandewie@xxxxxxxxx> wrote:
>>>
>>> From: Dirk Brandewie <dirk.brandewie@xxxxxxxxx>
>>>
>>> There is an additional reference added to the driver in
>>> cpufreq_add_dev() that is removed in__cpufreq_governor() if the
>>>
>>> driver implements target(). Remove the last reference when the
>>> driver implements setpolicy()
>>>
>>> Signed-off-by: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx>
>>>
>>> ---
>>> drivers/cpufreq/cpufreq.c | 3 +++
>>> 1 files changed, 3 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
>>> index 622e282..d17477b 100644
>>> --- a/drivers/cpufreq/cpufreq.c
>>> +++ b/drivers/cpufreq/cpufreq.c
>>> @@ -1049,6 +1049,9 @@ static int __cpufreq_remove_dev(struct device *dev,
>>> struct subsys_interface *sif
>>>
>>> if (cpufreq_driver->target)
>>> __cpufreq_governor(data, CPUFREQ_GOV_STOP);
>>>
>>> + if (cpufreq_driver->setpolicy)
>>> + cpufreq_cpu_put(data);
>>
>>
>> I don't understand this patch at all.. I grepped both cpufreq_cpu_get() &
>> put()
>> in bleeding-edge and found everything to be correct.
>>
>> Can you please point me to the exact line numbers ?
>>
>
> Line 878 in cpufreq_add_dev()

Following is line 878:

for_each_online_cpu(sibling) {
struct cpufreq_policy *cp = per_cpu(cpufreq_cpu_data, sibling);
if (cp && cpumask_test_cpu(cpu, cp->related_cpus))
return cpufreq_add_policy_cpu(cpu, sibling, dev);
}

How is this related to your patch?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/