From: Colin Cross <ccross@android.com>
Date: Sat, 29 Jan 2011 03:32:31 +0000 (-0800)
Subject: cpufreq: Prevent memory leak in cpufreq_stats on hotplug
X-Git-Tag: firefly_0821_release~4090^2~817
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=32d3498d047d71b706e7a55803203a969cc2bacf;p=firefly-linux-kernel-4.4.55.git

cpufreq: Prevent memory leak in cpufreq_stats on hotplug

Ensures that cpufreq_stats_free_table is called before
__cpufreq_remove_dev on cpu hotplug (which also occurs during
suspend on SMP systems) to make sure that sysfs_remove_group
can get called before the cpufreq kobj is freed.  Otherwise,
the sysfs file structures are leaked.

Change-Id: I87e55277272f5cfad47e9e7c92630e990bb90069
Signed-off-by: Colin Cross <ccross@android.com>
---

diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index fb65decffa28..2ccfaed7d844 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -341,6 +341,27 @@ static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
 	return 0;
 }
 
+static int cpufreq_stats_create_table_cpu(unsigned int cpu)
+{
+	struct cpufreq_policy *policy;
+	struct cpufreq_frequency_table *table;
+	int ret = -ENODEV;
+
+	policy = cpufreq_cpu_get(cpu);
+	if (!policy)
+		return -ENODEV;
+
+	table = cpufreq_frequency_get_table(cpu);
+	if (!table)
+		goto out;
+
+	ret = cpufreq_stats_create_table(policy, table);
+
+out:
+	cpufreq_cpu_put(policy);
+	return ret;
+}
+
 static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb,
 					       unsigned long action,
 					       void *hcpu)
@@ -361,6 +382,10 @@ static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb,
 		cpufreq_stats_free_sysfs(cpu);
 		cpufreq_stats_free_table(cpu);
 		break;
+	case CPU_DOWN_FAILED:
+	case CPU_DOWN_FAILED_FROZEN:
+		cpufreq_stats_create_table_cpu(cpu);
+		break;
 	}
 	return NOTIFY_OK;
 }