cpufreq: Use the fixed and coherent frequency for scaling capacity

commit 599457ba15403037b489fe536266a3d5f9efaed7 upstream.

cpuinfo.max_freq can change at runtime because of boost as an example. This
implies that the value could be different from the frequency that has been
used to compute the capacity of a CPU.

The new arch_scale_freq_ref() returns a fixed and coherent frequency
that can be used to compute the capacity for a given frequency.

[ Also fix a arch_set_freq_scale()  newline style wart in <linux/cpufreq.h>. ]

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20231211104855.558096-3-vincent.guittot@linaro.org
Stable-dep-of: e37617c8e53a ("sched/fair: Fix frequency selection for non-invariant case")
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 6ee1767ba08f50334381e71e3d47b5fb5ae3c0f3..30d8f2ada0f176344333bccc7849b9bb8d173206 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -454,7 +454,7 @@ void cpufreq_freq_transition_end(struct cpufreq_policy *policy,
 
        arch_set_freq_scale(policy->related_cpus,
                            policy->cur,
-                           policy->cpuinfo.max_freq);
+                           arch_scale_freq_ref(policy->cpu));
 
        spin_lock(&policy->transition_lock);
        policy->transition_ongoing = false;
@@ -2205,7 +2205,7 @@ unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,
 
        policy->cur = freq;
        arch_set_freq_scale(policy->related_cpus, freq,
-                           policy->cpuinfo.max_freq);
+                           arch_scale_freq_ref(policy->cpu));
        cpufreq_stats_record_transition(policy, freq);
 
        if (trace_cpu_frequency_enabled()) {

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 184a84dd467ec787faf91877a8d6fabd243d428d..bfecd9dcb5529754359a8e966314a58f8c59d531 100644 (file)
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -1245,6 +1245,7 @@ void arch_set_freq_scale(const struct cpumask *cpus,
 {
 }
 #endif
+
 /* the following are really really optional */
 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
 extern struct freq_attr cpufreq_freq_attr_scaling_boost_freqs;