Re: [PATCH v4 2/6] cpufreq: Add boost_freq_req QoS request

[Pierre Gondois]

On 2/25/26 03:33, zhenglifeng (A) wrote:
> On 2/25/2026 1:08 AM, Pierre Gondois wrote:
> > The Power Management Quality of Service (PM QoS) allows to
> > aggregate constraints from multiple entities. It is currently
> > used to manage the min/max frequency of a given policy.
> >
> > Frequency constraints can come for instance from:
> > - Thermal framework: acpi_thermal_cpufreq_init()
> > - Firmware: _PPC objects: acpi_processor_ppc_init()
> > - User: by setting policyX/scaling_[min|max]_freq
> > The minimum of the max frequency constraints is used to compute
> > the resulting maximum allowed frequency.
> >
> > When enabling boost frequencies, the same frequency request object
> > (policy->max_freq_req) as to handle requests from users is used.
> > As a result, when setting:
> > - scaling_max_freq
> > - boost
> > The last sysfs file used overwrites the request from the other
> > sysfs file.
> >
> > To avoid this, create a per-policy boost_freq_req to save the boost
> > constraints instead of overwriting the last scaling_max_freq
> > constraint.
> >
> > Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>
> > ---
> >   drivers/cpufreq/cpufreq.c | 41 ++++++++++++++++++++++++++++++++++-----
> >   include/linux/cpufreq.h   |  1 +
> >   2 files changed, 37 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> > index db414c052658b..52efa4805afee 100644
> > --- a/drivers/cpufreq/cpufreq.c
> > +++ b/drivers/cpufreq/cpufreq.c
> > @@ -1359,17 +1359,25 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy)
> >   	/* Cancel any pending policy->update work before freeing the policy. */
> >   	cancel_work_sync(&policy->update);
> >   
> > -	if (policy->max_freq_req) {
> > +	if (policy->max_freq_req || policy->boost_freq_req) {
> >   		/*
> > -		 * Remove max_freq_req after sending CPUFREQ_REMOVE_POLICY
> > -		 * notification, since CPUFREQ_CREATE_POLICY notification was
> > -		 * sent after adding max_freq_req earlier.
> > +		 * Remove max/boost _freq_req after sending CPUFREQ_REMOVE_POLICY
> > +		 * notification, since CPUFREQ_CREATE_POLICY notification was sent
> > +		 * after adding max/boost _freq_req earlier.
> >   		 */
> >   		blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
> >   					     CPUFREQ_REMOVE_POLICY, policy);
> > -		freq_qos_remove_request(policy->max_freq_req);
> >   	}
> >   
> > +	if ((policy->max_freq_req && !policy->boost_supported) ||
> > +	    policy->boost_freq_req) {
> Is this if statement written in the wrong place?

Yes right ...

I also forgot to remove the below if conditions as you suggessted


> > +		freq_qos_remove_request(policy->boost_freq_req);
> > +		kfree(policy->boost_freq_req);
> > +	}
> > +
> > +	if (policy->max_freq_req)
> > +		freq_qos_remove_request(policy->max_freq_req);
> > +
> >   	freq_qos_remove_request(policy->min_freq_req);
> >   	kfree(policy->min_freq_req);
> >