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-rw-r--r--drivers/cpufreq/cpufreq.c3
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c18
-rw-r--r--drivers/cpufreq/cpufreq_stats.c12
3 files changed, 21 insertions, 12 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 6c6121b85a54..25acf478c9e8 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -593,12 +593,11 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
goto module_out;
}
- policy = kmalloc(sizeof(struct cpufreq_policy), GFP_KERNEL);
+ policy = kzalloc(sizeof(struct cpufreq_policy), GFP_KERNEL);
if (!policy) {
ret = -ENOMEM;
goto nomem_out;
}
- memset(policy, 0, sizeof(struct cpufreq_policy));
policy->cpu = cpu;
policy->cpus = cpumask_of_cpu(cpu);
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index c1fc9c62bb51..17741111246b 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -48,7 +48,10 @@
* All times here are in uS.
*/
static unsigned int def_sampling_rate;
-#define MIN_SAMPLING_RATE (def_sampling_rate / 2)
+#define MIN_SAMPLING_RATE_RATIO (2)
+/* for correct statistics, we need at least 10 ticks between each measure */
+#define MIN_STAT_SAMPLING_RATE (MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10))
+#define MIN_SAMPLING_RATE (def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
#define MAX_SAMPLING_RATE (500 * def_sampling_rate)
#define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (1000)
#define DEF_SAMPLING_DOWN_FACTOR (1)
@@ -416,13 +419,16 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
if (dbs_enable == 1) {
unsigned int latency;
/* policy latency is in nS. Convert it to uS first */
+ latency = policy->cpuinfo.transition_latency / 1000;
+ if (latency == 0)
+ latency = 1;
- latency = policy->cpuinfo.transition_latency;
- if (latency < 1000)
- latency = 1000;
-
- def_sampling_rate = (latency / 1000) *
+ def_sampling_rate = latency *
DEF_SAMPLING_RATE_LATENCY_MULTIPLIER;
+
+ if (def_sampling_rate < MIN_STAT_SAMPLING_RATE)
+ def_sampling_rate = MIN_STAT_SAMPLING_RATE;
+
dbs_tuners_ins.sampling_rate = def_sampling_rate;
dbs_tuners_ins.ignore_nice = 0;
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index 3597f25d5efa..0bddb8e694d9 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -193,11 +193,15 @@ cpufreq_stats_create_table (struct cpufreq_policy *policy,
unsigned int cpu = policy->cpu;
if (cpufreq_stats_table[cpu])
return -EBUSY;
- if ((stat = kmalloc(sizeof(struct cpufreq_stats), GFP_KERNEL)) == NULL)
+ if ((stat = kzalloc(sizeof(struct cpufreq_stats), GFP_KERNEL)) == NULL)
return -ENOMEM;
- memset(stat, 0, sizeof (struct cpufreq_stats));
data = cpufreq_cpu_get(cpu);
+ if (data == NULL) {
+ ret = -EINVAL;
+ goto error_get_fail;
+ }
+
if ((ret = sysfs_create_group(&data->kobj, &stats_attr_group)))
goto error_out;
@@ -217,12 +221,11 @@ cpufreq_stats_create_table (struct cpufreq_policy *policy,
alloc_size += count * count * sizeof(int);
#endif
stat->max_state = count;
- stat->time_in_state = kmalloc(alloc_size, GFP_KERNEL);
+ stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
if (!stat->time_in_state) {
ret = -ENOMEM;
goto error_out;
}
- memset(stat->time_in_state, 0, alloc_size);
stat->freq_table = (unsigned int *)(stat->time_in_state + count);
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
@@ -245,6 +248,7 @@ cpufreq_stats_create_table (struct cpufreq_policy *policy,
return 0;
error_out:
cpufreq_cpu_put(data);
+error_get_fail:
kfree(stat);
cpufreq_stats_table[cpu] = NULL;
return ret;