Re: [PATCH] cpufreq: conservative: Fix incorrect frequency decrease due to stale target

[zhenglifeng (A)]

On 5/7/2026 5:33 PM, Viresh Kumar wrote:
> On 23-04-26, 15:12, zhenglifeng (A) wrote:
>> Yes, I think you are right. The behaviors are not the same. I modified this
>> just in order to keep it consistent with the case exceeding down_threshold.
>> I'm not sure if this change of behavior is reasonable. Perhaps Rafael or
>> Viresh could give us some advice.
> 
>>>> diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
>>>> @@ -104,7 +104,7 @@ static unsigned int cs_dbs_update(struct cpufreq_policy *policy)
>>>>           dbs_info->down_skip = 0;
>>>>             /* if we are already at full speed then break out early */
>>>> -        if (requested_freq == policy->max)
>>>> +        if (dbs_info->requested_freq == policy->max)
>>>>               goto out;
> 
>>>> -        if (requested_freq == policy->min)
>>>> +        if (dbs_info->requested_freq == policy->min)
> 
> What about dropping these `if` blocks completely ? i.e. always call
> __cpufreq_driver_target().
> 
> __cpufreq_driver_target() already have similar checks in place to optimize
> unnecessary freq changes. We don't really need callers to do the same.
> 

__cpufreq_driver_target() only skips this when !(cpufreq_driver->flags & CPUFREQ_NEED_UPDATE_LIMITS),
this means that for cppc_cpufreq, amd-pstate and intel_pstate the
unnecessary freq change will still be called.