#include <linux/jiffies.h>
#include <linux/kernel_stat.h>
#include <linux/percpu.h>
+#include <linux/mutex.h>
/*
* dbs is used in this file as a shortform for demandbased switching
#define MIN_FREQUENCY_UP_THRESHOLD (11)
#define MAX_FREQUENCY_UP_THRESHOLD (100)
-/*
- * The polling frequency of this governor depends on the capability of
+/*
+ * The polling frequency of this governor depends on the capability of
* the processor. Default polling frequency is 1000 times the transition
- * latency of the processor. The governor will work on any processor with
- * transition latency <= 10mS, using appropriate sampling
+ * latency of the processor. The governor will work on any processor with
+ * transition latency <= 10mS, using appropriate sampling
* rate.
* For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL)
* this governor will not work.
* All times here are in uS.
*/
-static unsigned int def_sampling_rate;
+static unsigned int def_sampling_rate;
#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))
static void do_dbs_timer(void *data);
struct cpu_dbs_info_s {
- struct cpufreq_policy *cur_policy;
- unsigned int prev_cpu_idle_up;
- unsigned int prev_cpu_idle_down;
- unsigned int enable;
+ struct cpufreq_policy *cur_policy;
+ unsigned int prev_cpu_idle_up;
+ unsigned int prev_cpu_idle_down;
+ unsigned int enable;
};
static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
static unsigned int dbs_enable; /* number of CPUs using this policy */
-static DECLARE_MUTEX (dbs_sem);
+static DEFINE_MUTEX (dbs_mutex);
static DECLARE_WORK (dbs_work, do_dbs_timer, NULL);
struct dbs_tuners {
- unsigned int sampling_rate;
- unsigned int sampling_down_factor;
- unsigned int up_threshold;
- unsigned int ignore_nice;
+ unsigned int sampling_rate;
+ unsigned int sampling_down_factor;
+ unsigned int up_threshold;
+ unsigned int ignore_nice;
};
static struct dbs_tuners dbs_tuners_ins = {
- .up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
- .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
+ .up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
+ .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
+ .ignore_nice = 0,
};
static inline unsigned int get_cpu_idle_time(unsigned int cpu)
{
return kstat_cpu(cpu).cpustat.idle +
kstat_cpu(cpu).cpustat.iowait +
- ( !dbs_tuners_ins.ignore_nice ?
+ ( dbs_tuners_ins.ignore_nice ?
kstat_cpu(cpu).cpustat.nice :
0);
}
return sprintf (buf, "%u\n", MIN_SAMPLING_RATE);
}
-#define define_one_ro(_name) \
-static struct freq_attr _name = \
+#define define_one_ro(_name) \
+static struct freq_attr _name = \
__ATTR(_name, 0444, show_##_name, NULL)
define_one_ro(sampling_rate_max);
show_one(sampling_rate, sampling_rate);
show_one(sampling_down_factor, sampling_down_factor);
show_one(up_threshold, up_threshold);
-show_one(ignore_nice, ignore_nice);
+show_one(ignore_nice_load, ignore_nice);
-static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
+static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
const char *buf, size_t count)
{
unsigned int input;
if (input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
return -EINVAL;
- down(&dbs_sem);
+ mutex_lock(&dbs_mutex);
dbs_tuners_ins.sampling_down_factor = input;
- up(&dbs_sem);
+ mutex_unlock(&dbs_mutex);
return count;
}
-static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
+static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
const char *buf, size_t count)
{
unsigned int input;
int ret;
ret = sscanf (buf, "%u", &input);
- down(&dbs_sem);
+ mutex_lock(&dbs_mutex);
if (ret != 1 || input > MAX_SAMPLING_RATE || input < MIN_SAMPLING_RATE) {
- up(&dbs_sem);
+ mutex_unlock(&dbs_mutex);
return -EINVAL;
}
dbs_tuners_ins.sampling_rate = input;
- up(&dbs_sem);
+ mutex_unlock(&dbs_mutex);
return count;
}
-static ssize_t store_up_threshold(struct cpufreq_policy *unused,
+static ssize_t store_up_threshold(struct cpufreq_policy *unused,
const char *buf, size_t count)
{
unsigned int input;
int ret;
ret = sscanf (buf, "%u", &input);
- down(&dbs_sem);
- if (ret != 1 || input > MAX_FREQUENCY_UP_THRESHOLD ||
+ mutex_lock(&dbs_mutex);
+ if (ret != 1 || input > MAX_FREQUENCY_UP_THRESHOLD ||
input < MIN_FREQUENCY_UP_THRESHOLD) {
- up(&dbs_sem);
+ mutex_unlock(&dbs_mutex);
return -EINVAL;
}
dbs_tuners_ins.up_threshold = input;
- up(&dbs_sem);
+ mutex_unlock(&dbs_mutex);
return count;
}
-static ssize_t store_ignore_nice(struct cpufreq_policy *policy,
+static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
const char *buf, size_t count)
{
unsigned int input;
int ret;
unsigned int j;
-
+
ret = sscanf (buf, "%u", &input);
if ( ret != 1 )
return -EINVAL;
if ( input > 1 )
input = 1;
-
- down(&dbs_sem);
+
+ mutex_lock(&dbs_mutex);
if ( input == dbs_tuners_ins.ignore_nice ) { /* nothing to do */
- up(&dbs_sem);
+ mutex_unlock(&dbs_mutex);
return count;
}
dbs_tuners_ins.ignore_nice = input;
j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j);
j_dbs_info->prev_cpu_idle_down = j_dbs_info->prev_cpu_idle_up;
}
- up(&dbs_sem);
+ mutex_unlock(&dbs_mutex);
return count;
}
define_one_rw(sampling_rate);
define_one_rw(sampling_down_factor);
define_one_rw(up_threshold);
-define_one_rw(ignore_nice);
+define_one_rw(ignore_nice_load);
static struct attribute * dbs_attributes[] = {
&sampling_rate_max.attr,
&sampling_rate.attr,
&sampling_down_factor.attr,
&up_threshold.attr,
- &ignore_nice.attr,
+ &ignore_nice_load.attr,
NULL
};
return;
policy = this_dbs_info->cur_policy;
- /*
+ /*
* Every sampling_rate, we check, if current idle time is less
* than 20% (default), then we try to increase frequency
* Every sampling_rate*sampling_down_factor, we look for a the lowest
* frequency which can sustain the load while keeping idle time over
* 30%. If such a frequency exist, we try to decrease to this frequency.
*
- * Any frequency increase takes it to the maximum frequency.
- * Frequency reduction happens at minimum steps of
- * 5% (default) of current frequency
+ * Any frequency increase takes it to the maximum frequency.
+ * Frequency reduction happens at minimum steps of
+ * 5% (default) of current frequency
*/
/* Check for frequency increase */
struct cpu_dbs_info_s *j_dbs_info;
j_dbs_info = &per_cpu(cpu_dbs_info, j);
- j_dbs_info->prev_cpu_idle_down =
+ j_dbs_info->prev_cpu_idle_down =
j_dbs_info->prev_cpu_idle_up;
}
/* if we are already at full speed then break out early */
if (policy->cur == policy->max)
return;
-
- __cpufreq_driver_target(policy, policy->max,
+
+ __cpufreq_driver_target(policy, policy->max,
CPUFREQ_RELATION_H);
return;
}
* policy. To be safe, we focus 10 points under the threshold.
*/
freq_next = ((total_ticks - idle_ticks) * 100) / total_ticks;
- freq_next = (freq_next * policy->cur) /
+ freq_next = (freq_next * policy->cur) /
(dbs_tuners_ins.up_threshold - 10);
if (freq_next <= ((policy->cur * 95) / 100))
}
static void do_dbs_timer(void *data)
-{
+{
int i;
- down(&dbs_sem);
+ mutex_lock(&dbs_mutex);
for_each_online_cpu(i)
dbs_check_cpu(i);
- schedule_delayed_work(&dbs_work,
+ schedule_delayed_work(&dbs_work,
usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
- up(&dbs_sem);
-}
+ mutex_unlock(&dbs_mutex);
+}
static inline void dbs_timer_init(void)
{
switch (event) {
case CPUFREQ_GOV_START:
- if ((!cpu_online(cpu)) ||
+ if ((!cpu_online(cpu)) ||
(!policy->cur))
return -EINVAL;
if (policy->cpuinfo.transition_latency >
- (TRANSITION_LATENCY_LIMIT * 1000))
+ (TRANSITION_LATENCY_LIMIT * 1000)) {
+ printk(KERN_WARNING "ondemand governor failed to load "
+ "due to too long transition latency\n");
return -EINVAL;
+ }
if (this_dbs_info->enable) /* Already enabled */
break;
-
- down(&dbs_sem);
+
+ mutex_lock(&dbs_mutex);
for_each_cpu_mask(j, policy->cpus) {
struct cpu_dbs_info_s *j_dbs_info;
j_dbs_info = &per_cpu(cpu_dbs_info, j);
j_dbs_info->cur_policy = policy;
-
+
j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j);
j_dbs_info->prev_cpu_idle_down
= j_dbs_info->prev_cpu_idle_up;
def_sampling_rate = MIN_STAT_SAMPLING_RATE;
dbs_tuners_ins.sampling_rate = def_sampling_rate;
- dbs_tuners_ins.ignore_nice = 0;
-
dbs_timer_init();
}
-
- up(&dbs_sem);
+
+ mutex_unlock(&dbs_mutex);
break;
case CPUFREQ_GOV_STOP:
- down(&dbs_sem);
+ mutex_lock(&dbs_mutex);
this_dbs_info->enable = 0;
sysfs_remove_group(&policy->kobj, &dbs_attr_group);
dbs_enable--;
* Stop the timerschedule work, when this governor
* is used for first time
*/
- if (dbs_enable == 0)
+ if (dbs_enable == 0)
dbs_timer_exit();
-
- up(&dbs_sem);
+
+ mutex_unlock(&dbs_mutex);
break;
case CPUFREQ_GOV_LIMITS:
- down(&dbs_sem);
+ mutex_lock(&dbs_mutex);
if (policy->max < this_dbs_info->cur_policy->cur)
__cpufreq_driver_target(
this_dbs_info->cur_policy,
- policy->max, CPUFREQ_RELATION_H);
+ policy->max, CPUFREQ_RELATION_H);
else if (policy->min > this_dbs_info->cur_policy->cur)
__cpufreq_driver_target(
this_dbs_info->cur_policy,
- policy->min, CPUFREQ_RELATION_L);
- up(&dbs_sem);
+ policy->min, CPUFREQ_RELATION_L);
+ mutex_unlock(&dbs_mutex);
break;
}
return 0;
git.openpandora.org / pandora-kernel.git / blobdiff