4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Rafael J. Wysocki <[email protected]>

commit 4296f23ed49a15d36949458adcc66ff993dee2a8 upstream.

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 <[email protected]>
Acked-by: Viresh Kumar <[email protected]>
Signed-off-by: Amit Pundir <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 kernel/sched/cpufreq_schedutil.c |   20 +++++++-------------
 1 file changed, 7 insertions(+), 13 deletions(-)

--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -507,20 +507,14 @@ 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;
 }


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