[PATCH 1/2] cpufreq: schedutil: Fix per-CPU structure initialization in sugov_start()

From: Rafael J. Wysocki
Date: Sun Mar 19 2017 - 09:41:52 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

sugov_start() only initializes struct sugov_cpu per-CPU structures
for shared policies, but it should do that for single-CPU policies too.

That in particular makes the IO-wait boost mechanism work in the
cases when cpufreq policies correspond to individual CPUs.

Fixes: 21ca6d2c52f8 (cpufreq: schedutil: Add iowait boosting)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
kernel/sched/cpufreq_schedutil.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)

Index: linux-pm/kernel/sched/cpufreq_schedutil.c
===================================================================
--- linux-pm.orig/kernel/sched/cpufreq_schedutil.c
+++ linux-pm/kernel/sched/cpufreq_schedutil.c
@@ -577,20 +577,14 @@ static int sugov_start(struct cpufreq_po
for_each_cpu(cpu, policy->cpus) {
struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu);

+ memset(sg_cpu, 0, sizeof(*sg_cpu));
sg_cpu->sg_policy = sg_policy;
- if (policy_is_shared(policy)) {
- sg_cpu->util = 0;
- sg_cpu->max = 0;
- sg_cpu->flags = SCHED_CPUFREQ_RT;
- sg_cpu->last_update = 0;
- sg_cpu->iowait_boost = 0;
- sg_cpu->iowait_boost_max = policy->cpuinfo.max_freq;
- cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util,
- sugov_update_shared);
- } else {
- cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util,
- sugov_update_single);
- }
+ sg_cpu->flags = SCHED_CPUFREQ_RT;
+ sg_cpu->iowait_boost_max = policy->cpuinfo.max_freq;
+ cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util,
+ policy_is_shared(policy) ?
+ sugov_update_shared :
+ sugov_update_single);
}
return 0;
}