[1/2] cpufreq: schedutil: Fix per-CPU structure initialization in sugov_start()
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Message ID 2230625.Zj7J7bOCCf@aspire.rjw.lan
State Mainlined
Delegated to: Rafael Wysocki
Headers show

Commit Message

Rafael J. Wysocki March 19, 2017, 1:30 p.m. UTC
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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

Comments

Viresh Kumar March 20, 2017, 3:28 a.m. UTC | #1
On 19-03-17, 14:30, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> 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@intel.com>

Cc: 4.9+ <stable@vger.kernel.org> # 4.9+

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki March 20, 2017, 12:36 p.m. UTC | #2
On Monday, March 20, 2017 08:58:40 AM Viresh Kumar wrote:
> On 19-03-17, 14:30, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > 
> > 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@intel.com>
> 
> Cc: 4.9+ <stable@vger.kernel.org> # 4.9+

"stable" checks Fixes: tags too, but yes.

> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

Thanks,
Rafael

Patch
diff mbox

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;
 }