unsigned int up_threshold;
unsigned int down_threshold;
unsigned int ignore_nice;
+ unsigned int freq_step;
};
static struct dbs_tuners dbs_tuners_ins = {
.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
};
+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 ?
+ kstat_cpu(cpu).cpustat.nice :
+ 0);
+}
+
/************************** sysfs interface ************************/
static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf)
{
show_one(up_threshold, up_threshold);
show_one(down_threshold, down_threshold);
show_one(ignore_nice, ignore_nice);
+show_one(freq_step, freq_step);
static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
const char *buf, size_t count)
dbs_tuners_ins.ignore_nice = input;
/* we need to re-evaluate prev_cpu_idle_up and prev_cpu_idle_down */
- for_each_cpu_mask(j, policy->cpus) {
+ for_each_online_cpu(j) {
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 =
- kstat_cpu(j).cpustat.idle +
- kstat_cpu(j).cpustat.iowait +
- ( !dbs_tuners_ins.ignore_nice
- ? kstat_cpu(j).cpustat.nice : 0 );
+ 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);
return count;
}
+static ssize_t store_freq_step(struct cpufreq_policy *policy,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+
+ ret = sscanf (buf, "%u", &input);
+
+ if ( ret != 1 )
+ return -EINVAL;
+
+ if ( input > 100 )
+ input = 100;
+
+ /* no need to test here if freq_step is zero as the user might actually
+ * want this, they would be crazy though :) */
+ down(&dbs_sem);
+ dbs_tuners_ins.freq_step = input;
+ up(&dbs_sem);
+
+ return count;
+}
+
#define define_one_rw(_name) \
static struct freq_attr _name = \
__ATTR(_name, 0644, show_##_name, store_##_name)
define_one_rw(up_threshold);
define_one_rw(down_threshold);
define_one_rw(ignore_nice);
+define_one_rw(freq_step);
static struct attribute * dbs_attributes[] = {
&sampling_rate_max.attr,
&up_threshold.attr,
&down_threshold.attr,
&ignore_nice.attr,
+ &freq_step.attr,
NULL
};
*
* Any frequency increase takes it to the maximum frequency.
* Frequency reduction happens at minimum steps of
- * 5% of max_frequency
+ * 5% (default) of max_frequency
*/
/* Check for frequency increase */
- total_idle_ticks = kstat_cpu(cpu).cpustat.idle +
- kstat_cpu(cpu).cpustat.iowait;
- /* consider 'nice' tasks as 'idle' time too if required */
- if (dbs_tuners_ins.ignore_nice == 0)
- total_idle_ticks += kstat_cpu(cpu).cpustat.nice;
+ total_idle_ticks = get_cpu_idle_time(cpu);
idle_ticks = total_idle_ticks -
this_dbs_info->prev_cpu_idle_up;
this_dbs_info->prev_cpu_idle_up = total_idle_ticks;
-
for_each_cpu_mask(j, policy->cpus) {
unsigned int tmp_idle_ticks;
j_dbs_info = &per_cpu(cpu_dbs_info, j);
/* Check for frequency increase */
- total_idle_ticks = kstat_cpu(j).cpustat.idle +
- kstat_cpu(j).cpustat.iowait;
- /* consider 'nice' too? */
- if (dbs_tuners_ins.ignore_nice == 0)
- total_idle_ticks += kstat_cpu(j).cpustat.nice;
+ total_idle_ticks = get_cpu_idle_time(j);
tmp_idle_ticks = total_idle_ticks -
j_dbs_info->prev_cpu_idle_up;
j_dbs_info->prev_cpu_idle_up = total_idle_ticks;
usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
if (idle_ticks < up_idle_ticks) {
+ down_skip[cpu] = 0;
+ 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->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_RELATION_H);
- down_skip[cpu] = 0;
- this_dbs_info->prev_cpu_idle_down = total_idle_ticks;
return;
}
if (down_skip[cpu] < dbs_tuners_ins.sampling_down_factor)
return;
- total_idle_ticks = kstat_cpu(cpu).cpustat.idle +
- kstat_cpu(cpu).cpustat.iowait;
- /* consider 'nice' too? */
- if (dbs_tuners_ins.ignore_nice == 0)
- total_idle_ticks += kstat_cpu(cpu).cpustat.nice;
+ total_idle_ticks = this_dbs_info->prev_cpu_idle_up;
idle_ticks = total_idle_ticks -
this_dbs_info->prev_cpu_idle_down;
this_dbs_info->prev_cpu_idle_down = total_idle_ticks;
continue;
j_dbs_info = &per_cpu(cpu_dbs_info, j);
- /* Check for frequency increase */
- total_idle_ticks = kstat_cpu(j).cpustat.idle +
- kstat_cpu(j).cpustat.iowait;
- /* consider 'nice' too? */
- if (dbs_tuners_ins.ignore_nice == 0)
- total_idle_ticks += kstat_cpu(j).cpustat.nice;
+ /* Check for frequency decrease */
+ total_idle_ticks = j_dbs_info->prev_cpu_idle_up;
tmp_idle_ticks = total_idle_ticks -
j_dbs_info->prev_cpu_idle_down;
j_dbs_info->prev_cpu_idle_down = total_idle_ticks;
freq_down_sampling_rate = dbs_tuners_ins.sampling_rate *
dbs_tuners_ins.sampling_down_factor;
down_idle_ticks = (100 - dbs_tuners_ins.down_threshold) *
- usecs_to_jiffies(freq_down_sampling_rate);
+ usecs_to_jiffies(freq_down_sampling_rate);
if (idle_ticks > down_idle_ticks ) {
- freq_down_step = (5 * policy->max) / 100;
+ /* if we are already at the lowest speed then break out early
+ * or if we 'cannot' reduce the speed as the user might want
+ * freq_step to be zero */
+ if (policy->cur == policy->min || dbs_tuners_ins.freq_step == 0)
+ return;
+
+ freq_down_step = (dbs_tuners_ins.freq_step * policy->max) / 100;
/* max freq cannot be less than 100. But who knows.... */
if (unlikely(freq_down_step == 0))
freq_down_step = 5;
__cpufreq_driver_target(policy,
- policy->cur - freq_down_step,
+ policy->cur - freq_down_step,
CPUFREQ_RELATION_H);
return;
}
j_dbs_info = &per_cpu(cpu_dbs_info, j);
j_dbs_info->cur_policy = policy;
- j_dbs_info->prev_cpu_idle_up =
- kstat_cpu(j).cpustat.idle +
- kstat_cpu(j).cpustat.iowait +
- ( !dbs_tuners_ins.ignore_nice
- ? kstat_cpu(j).cpustat.nice : 0 );
+ 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_LATENCY_MULTIPLIER;
dbs_tuners_ins.sampling_rate = def_sampling_rate;
dbs_tuners_ins.ignore_nice = 0;
+ dbs_tuners_ins.freq_step = 5;
dbs_timer_init();
}