[PATCH 1/2] cpufreq: schedutil: Don't restrict kthread to related_cpus unnecessarily

From: Viresh Kumar
Date: Thu Aug 10 2017 - 00:21:18 EST


Utilization update callbacks are now processed remotely, even on the
CPUs that don't share cpufreq policy with the target CPU (if
dvfs_possible_from_any_cpu flag is set).

But in non-fast switch paths, the frequency is changed only from one of
policy->related_cpus. This happens because the kthread which does the
actual update is bound to a subset of CPUs (i.e. related_cpus).

Allow frequency to be remotely updated as well (i.e. call
__cpufreq_driver_target()) if dvfs_possible_from_any_cpu flag is set.

Reported-by: Pavan Kondeti <pkondeti@xxxxxxxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
kernel/sched/cpufreq_schedutil.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 2e74c49776be..504d0752f8f2 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -487,7 +487,11 @@ static int sugov_kthread_create(struct sugov_policy *sg_policy)
}

sg_policy->thread = thread;
- kthread_bind_mask(thread, policy->related_cpus);
+
+ /* Kthread is bound to all CPUs by default */
+ if (!policy->dvfs_possible_from_any_cpu)
+ kthread_bind_mask(thread, policy->related_cpus);
+
init_irq_work(&sg_policy->irq_work, sugov_irq_work);
mutex_init(&sg_policy->work_lock);

--
2.13.0.71.gd7076ec9c9cb