[PATCH V3] cpufreq: Restore policy min/max limits on CPU online

From: Viresh Kumar
Date: Tue Mar 21 2017 - 02:14:09 EST


On CPU online the cpufreq core restores the previous governor (or
the previous "policy" setting for ->setpolicy drivers), but it does
not restore the min/max limits at the same time, which is confusing,
inconsistent and real pain for users who set the limits and then
suspend/resume the system (using full suspend), in which case the
limits are reset on all CPUs except for the boot one.

Fix this by making cpufreq_online() restore the limits when an inactive
policy is brought online.

The commit log and patch are inspired from Rafael's earlier work.

Reported-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
V1 and V2 were sent by Rafael and were trying to fix this differently.

drivers/cpufreq/cpufreq.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 38b9fdf854a4..87e7b9d0db1b 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1182,6 +1182,9 @@ static int cpufreq_online(unsigned int cpu)
for_each_cpu(j, policy->related_cpus)
per_cpu(cpufreq_cpu_data, j) = policy;
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ } else {
+ policy->min = policy->user_policy.min;
+ policy->max = policy->user_policy.max;
}

if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
--
2.12.0.432.g71c3a4f4ba37