diff mbox series

[v3,2/6] cpufreq: use the fixed and coherent frequency for scaling capacity

Message ID 20231018162540.667646-3-vincent.guittot@linaro.org
State Superseded
Headers show
Series consolidate and cleanup CPU capacity | expand

Commit Message

Vincent Guittot Oct. 18, 2023, 4:25 p.m. UTC 
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.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>

---
 drivers/cpufreq/cpufreq.c | 4 ++--
 include/linux/cpufreq.h   | 9 +++++++++
 2 files changed, 11 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 60ed89000e82..8c4f9c2f9c44 100644
--- 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;
@@ -2174,7 +2174,7 @@  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 71d186d6933a..bbc483b4b6e5 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -1211,6 +1211,15 @@  void arch_set_freq_scale(const struct cpumask *cpus,
 {
 }
 #endif
+
+#ifndef arch_scale_freq_ref
+static __always_inline
+unsigned int arch_scale_freq_ref(int cpu)
+{
+	return 0;
+}
+#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;