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path: root/drivers/cpufreq/cpufreq_ondemand.c
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Diffstat (limited to 'drivers/cpufreq/cpufreq_ondemand.c')
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c65
1 files changed, 35 insertions, 30 deletions
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index f56debd..42fcb14 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -334,9 +334,7 @@ static struct attribute_group dbs_attr_group = {
static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
{
- unsigned int idle_ticks, total_ticks;
- unsigned int load = 0;
- cputime64_t cur_jiffies;
+ unsigned int max_load_freq;
struct cpufreq_policy *policy;
unsigned int j;
@@ -346,13 +344,7 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
this_dbs_info->freq_lo = 0;
policy = this_dbs_info->cur_policy;
- cur_jiffies = jiffies64_to_cputime64(get_jiffies_64());
- total_ticks = (unsigned int) cputime64_sub(cur_jiffies,
- this_dbs_info->prev_cpu_wall);
- this_dbs_info->prev_cpu_wall = get_jiffies_64();
- if (!total_ticks)
- return;
/*
* Every sampling_rate, we check, if current idle time is less
* than 20% (default), then we try to increase frequency
@@ -365,27 +357,46 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
* 5% (default) of current frequency
*/
- /* Get Idle Time */
- idle_ticks = UINT_MAX;
+ /* Get Absolute Load - in terms of freq */
+ max_load_freq = 0;
+
for_each_cpu_mask_nr(j, policy->cpus) {
- cputime64_t total_idle_ticks;
- unsigned int tmp_idle_ticks;
struct cpu_dbs_info_s *j_dbs_info;
+ cputime64_t cur_wall_time, cur_idle_time;
+ unsigned int idle_time, wall_time;
+ unsigned int load, load_freq;
+ int freq_avg;
j_dbs_info = &per_cpu(cpu_dbs_info, j);
- total_idle_ticks = get_cpu_idle_time(j);
- tmp_idle_ticks = (unsigned int) cputime64_sub(total_idle_ticks,
+ cur_wall_time = jiffies64_to_cputime64(get_jiffies_64());
+ wall_time = (unsigned int) cputime64_sub(cur_wall_time,
+ j_dbs_info->prev_cpu_wall);
+ j_dbs_info->prev_cpu_wall = cur_wall_time;
+
+ cur_idle_time = get_cpu_idle_time(j);
+ idle_time = (unsigned int) cputime64_sub(cur_idle_time,
j_dbs_info->prev_cpu_idle);
- j_dbs_info->prev_cpu_idle = total_idle_ticks;
+ j_dbs_info->prev_cpu_idle = cur_idle_time;
- if (tmp_idle_ticks < idle_ticks)
- idle_ticks = tmp_idle_ticks;
+ if (unlikely(wall_time <= idle_time ||
+ (cputime_to_msecs(wall_time) <
+ dbs_tuners_ins.sampling_rate / (2 * 1000)))) {
+ continue;
+ }
+
+ load = 100 * (wall_time - idle_time) / wall_time;
+
+ freq_avg = __cpufreq_driver_getavg(policy, j);
+ if (freq_avg <= 0)
+ freq_avg = policy->cur;
+
+ load_freq = load * freq_avg;
+ if (load_freq > max_load_freq)
+ max_load_freq = load_freq;
}
- if (likely(total_ticks > idle_ticks))
- load = (100 * (total_ticks - idle_ticks)) / total_ticks;
/* Check for frequency increase */
- if (load > dbs_tuners_ins.up_threshold) {
+ if (max_load_freq > dbs_tuners_ins.up_threshold * policy->cur) {
/* if we are already at full speed then break out early */
if (!dbs_tuners_ins.powersave_bias) {
if (policy->cur == policy->max)
@@ -412,15 +423,9 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
* can support the current CPU usage without triggering the up
* policy. To be safe, we focus 10 points under the threshold.
*/
- if (load < (dbs_tuners_ins.up_threshold - 10)) {
- unsigned int freq_next, freq_cur;
-
- freq_cur = __cpufreq_driver_getavg(policy, policy->cpu);
- if (!freq_cur)
- freq_cur = policy->cur;
-
- freq_next = (freq_cur * load) /
- (dbs_tuners_ins.up_threshold - 10);
+ if (max_load_freq < (dbs_tuners_ins.up_threshold - 10) * policy->cur) {
+ unsigned int freq_next;
+ freq_next = max_load_freq / (dbs_tuners_ins.up_threshold - 10);
if (!dbs_tuners_ins.powersave_bias) {
__cpufreq_driver_target(policy, freq_next,
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