[PATCH v5 03/23] PM: EM: Find first CPU active while updating OPP efficiency

Lukasz Luba
2023-11-29T11:08:23Z

The Energy Model might be updated at runtime and the energy efficiency
for each OPP may change. Thus, there is a need to update also the
cpufreq framework and make it aligned to the new values. In order to
do that, use a first active CPU from the Performance Domain. This is
needed since the first CPU in the cpumask might be offline when we
run this code path.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
---
kernel/power/energy_model.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
index 42486674b834..aa7c89f9e115 100644
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -243,12 +243,19 @@ em_cpufreq_update_efficiencies(struct device *dev, struct em_perf_state *table)
struct em_perf_domain *pd = dev->em_pd;
struct cpufreq_policy *policy;
int found = 0;
- int i;
+ int i, cpu;

if (!_is_cpu_device(dev) || !pd)
return;

- policy = cpufreq_cpu_get(cpumask_first(em_span_cpus(pd)));
+ /* Try to get a CPU which is active and in this PD */
+ cpu = cpumask_first_and(em_span_cpus(pd), cpu_active_mask);
+ if (cpu >= nr_cpu_ids) {
+ dev_warn(dev, "EM: No online CPU for CPUFreq policy\n");
+ return;
+ }
+
+ policy = cpufreq_cpu_get(cpu);
if (!policy) {
dev_warn(dev, "EM: Access to CPUFreq policy failed\n");
return;
--
2.25.1