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))
-#define MIN_SAMPLING_RATE (def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
+#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 TRANSITION_LATENCY_LIMIT (10 * 1000)
static void do_dbs_timer(struct work_struct *work);
/* Sampling types */
-enum dbs_sample {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE};
+enum {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE};
struct cpu_dbs_info_s {
cputime64_t prev_cpu_idle;
cputime64_t prev_cpu_wall;
struct cpufreq_policy *cur_policy;
struct delayed_work work;
- enum dbs_sample sample_type;
- unsigned int enable;
struct cpufreq_frequency_table *freq_table;
unsigned int freq_lo;
unsigned int freq_lo_jiffies;
unsigned int freq_hi_jiffies;
+ int cpu;
+ unsigned int enable:1,
+ sample_type:1;
};
static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
ret = sscanf(buf, "%u", &input);
mutex_lock(&dbs_mutex);
- if (ret != 1 || input > MAX_SAMPLING_RATE || input < MIN_SAMPLING_RATE) {
+ if (ret != 1 || input > MAX_SAMPLING_RATE
+ || input < MIN_SAMPLING_RATE) {
mutex_unlock(&dbs_mutex);
return -EINVAL;
}
* policy. To be safe, we focus 10 points under the threshold.
*/
if (load < (dbs_tuners_ins.up_threshold - 10)) {
- unsigned int freq_next = (policy->cur * load) /
+ unsigned int freq_next, freq_cur;
+
+ freq_cur = __cpufreq_driver_getavg(policy);
+ if (!freq_cur)
+ freq_cur = policy->cur;
+
+ freq_next = (freq_cur * load) /
(dbs_tuners_ins.up_threshold - 10);
+
if (!dbs_tuners_ins.powersave_bias) {
__cpufreq_driver_target(policy, freq_next,
CPUFREQ_RELATION_L);
static void do_dbs_timer(struct work_struct *work)
{
- unsigned int cpu = smp_processor_id();
- struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
- enum dbs_sample sample_type = dbs_info->sample_type;
+ struct cpu_dbs_info_s *dbs_info =
+ container_of(work, struct cpu_dbs_info_s, work.work);
+ unsigned int cpu = dbs_info->cpu;
+ int sample_type = dbs_info->sample_type;
+
/* We want all CPUs to do sampling nearly on same jiffy */
int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
- /* Permit rescheduling of this work item */
- work_release(work);
-
delay -= jiffies % delay;
- if (!dbs_info->enable)
+ if (lock_policy_rwsem_write(cpu) < 0)
+ return;
+
+ if (!dbs_info->enable) {
+ unlock_policy_rwsem_write(cpu);
return;
+ }
+
/* Common NORMAL_SAMPLE setup */
dbs_info->sample_type = DBS_NORMAL_SAMPLE;
if (!dbs_tuners_ins.powersave_bias ||
sample_type == DBS_NORMAL_SAMPLE) {
- lock_cpu_hotplug();
dbs_check_cpu(dbs_info);
- unlock_cpu_hotplug();
if (dbs_info->freq_lo) {
/* Setup timer for SUB_SAMPLE */
dbs_info->sample_type = DBS_SUB_SAMPLE;
CPUFREQ_RELATION_H);
}
queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay);
+ unlock_policy_rwsem_write(cpu);
}
-static inline void dbs_timer_init(unsigned int cpu)
+static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info)
{
- struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
/* We want all CPUs to do sampling nearly on same jiffy */
int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
delay -= jiffies % delay;
+ dbs_info->enable = 1;
ondemand_powersave_bias_init();
- INIT_DELAYED_WORK_NAR(&dbs_info->work, do_dbs_timer);
dbs_info->sample_type = DBS_NORMAL_SAMPLE;
- queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay);
+ INIT_DELAYED_WORK_DEFERRABLE(&dbs_info->work, do_dbs_timer);
+ queue_delayed_work_on(dbs_info->cpu, kondemand_wq, &dbs_info->work,
+ delay);
}
static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info)
{
dbs_info->enable = 0;
cancel_delayed_work(&dbs_info->work);
- flush_workqueue(kondemand_wq);
}
static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
unsigned int cpu = policy->cpu;
struct cpu_dbs_info_s *this_dbs_info;
unsigned int j;
+ int rc;
this_dbs_info = &per_cpu(cpu_dbs_info, cpu);
mutex_lock(&dbs_mutex);
dbs_enable++;
- if (dbs_enable == 1) {
- kondemand_wq = create_workqueue("kondemand");
- if (!kondemand_wq) {
- printk(KERN_ERR "Creation of kondemand failed\n");
- dbs_enable--;
- mutex_unlock(&dbs_mutex);
- return -ENOSPC;
- }
+
+ rc = sysfs_create_group(&policy->kobj, &dbs_attr_group);
+ if (rc) {
+ dbs_enable--;
+ mutex_unlock(&dbs_mutex);
+ return rc;
}
+
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 = get_cpu_idle_time(j);
j_dbs_info->prev_cpu_wall = get_jiffies_64();
}
- this_dbs_info->enable = 1;
- sysfs_create_group(&policy->kobj, &dbs_attr_group);
+ this_dbs_info->cpu = cpu;
/*
* Start the timerschedule work, when this governor
* is used for first time
dbs_tuners_ins.sampling_rate = def_sampling_rate;
}
- dbs_timer_init(policy->cpu);
+ dbs_timer_init(this_dbs_info);
mutex_unlock(&dbs_mutex);
break;
dbs_timer_exit(this_dbs_info);
sysfs_remove_group(&policy->kobj, &dbs_attr_group);
dbs_enable--;
- if (dbs_enable == 0)
- destroy_workqueue(kondemand_wq);
-
mutex_unlock(&dbs_mutex);
break;
static int __init cpufreq_gov_dbs_init(void)
{
+ kondemand_wq = create_workqueue("kondemand");
+ if (!kondemand_wq) {
+ printk(KERN_ERR "Creation of kondemand failed\n");
+ return -EFAULT;
+ }
return cpufreq_register_governor(&cpufreq_gov_dbs);
}
static void __exit cpufreq_gov_dbs_exit(void)
{
cpufreq_unregister_governor(&cpufreq_gov_dbs);
+ destroy_workqueue(kondemand_wq);
}
module_init(cpufreq_gov_dbs_init);
module_exit(cpufreq_gov_dbs_exit);
+