diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq_ondemand.c | 157 |
1 files changed, 140 insertions, 17 deletions
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index f507a86..34874c2 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -55,6 +55,10 @@ struct cpu_dbs_info_s { struct cpufreq_policy *cur_policy; struct work_struct work; unsigned int enable; + struct cpufreq_frequency_table *freq_table; + unsigned int freq_lo; + unsigned int freq_lo_jiffies; + unsigned int freq_hi_jiffies; }; static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info); @@ -72,15 +76,15 @@ static DEFINE_MUTEX(dbs_mutex); static struct workqueue_struct *kondemand_wq; -struct dbs_tuners { +static struct dbs_tuners { unsigned int sampling_rate; unsigned int up_threshold; unsigned int ignore_nice; -}; - -static struct dbs_tuners dbs_tuners_ins = { + unsigned int powersave_bias; +} dbs_tuners_ins = { .up_threshold = DEF_FREQUENCY_UP_THRESHOLD, .ignore_nice = 0, + .powersave_bias = 0, }; static inline cputime64_t get_cpu_idle_time(unsigned int cpu) @@ -96,6 +100,69 @@ static inline cputime64_t get_cpu_idle_time(unsigned int cpu) return retval; } +/* + * Find right freq to be set now with powersave_bias on. + * Returns the freq_hi to be used right now and will set freq_hi_jiffies, + * freq_lo, and freq_lo_jiffies in percpu area for averaging freqs. + */ +unsigned int powersave_bias_target(struct cpufreq_policy *policy, + unsigned int freq_next, unsigned int relation) +{ + unsigned int freq_req, freq_reduc, freq_avg; + unsigned int freq_hi, freq_lo; + unsigned int index = 0; + unsigned int jiffies_total, jiffies_hi, jiffies_lo; + struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, policy->cpu); + + if (!dbs_info->freq_table) { + dbs_info->freq_lo = 0; + dbs_info->freq_lo_jiffies = 0; + return freq_next; + } + + cpufreq_frequency_table_target(policy, dbs_info->freq_table, freq_next, + relation, &index); + freq_req = dbs_info->freq_table[index].frequency; + freq_reduc = freq_req * dbs_tuners_ins.powersave_bias / 1000; + freq_avg = freq_req - freq_reduc; + + /* Find freq bounds for freq_avg in freq_table */ + index = 0; + cpufreq_frequency_table_target(policy, dbs_info->freq_table, freq_avg, + CPUFREQ_RELATION_H, &index); + freq_lo = dbs_info->freq_table[index].frequency; + index = 0; + cpufreq_frequency_table_target(policy, dbs_info->freq_table, freq_avg, + CPUFREQ_RELATION_L, &index); + freq_hi = dbs_info->freq_table[index].frequency; + + /* Find out how long we have to be in hi and lo freqs */ + if (freq_hi == freq_lo) { + dbs_info->freq_lo = 0; + dbs_info->freq_lo_jiffies = 0; + return freq_lo; + } + jiffies_total = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); + jiffies_hi = (freq_avg - freq_lo) * jiffies_total; + jiffies_hi += ((freq_hi - freq_lo) / 2); + jiffies_hi /= (freq_hi - freq_lo); + jiffies_lo = jiffies_total - jiffies_hi; + dbs_info->freq_lo = freq_lo; + dbs_info->freq_lo_jiffies = jiffies_lo; + dbs_info->freq_hi_jiffies = jiffies_hi; + return freq_hi; +} + +static void ondemand_powersave_bias_init(void) +{ + int i; + for_each_online_cpu(i) { + struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, i); + dbs_info->freq_table = cpufreq_frequency_get_table(i); + dbs_info->freq_lo = 0; + } +} + /************************** sysfs interface ************************/ static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf) { @@ -124,6 +191,7 @@ static ssize_t show_##file_name \ show_one(sampling_rate, sampling_rate); show_one(up_threshold, up_threshold); show_one(ignore_nice_load, ignore_nice); +show_one(powersave_bias, powersave_bias); static ssize_t store_sampling_rate(struct cpufreq_policy *unused, const char *buf, size_t count) @@ -198,6 +266,27 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy, return count; } +static ssize_t store_powersave_bias(struct cpufreq_policy *unused, + const char *buf, size_t count) +{ + unsigned int input; + int ret; + ret = sscanf(buf, "%u", &input); + + if (ret != 1) + return -EINVAL; + + if (input > 1000) + input = 1000; + + mutex_lock(&dbs_mutex); + dbs_tuners_ins.powersave_bias = input; + ondemand_powersave_bias_init(); + mutex_unlock(&dbs_mutex); + + return count; +} + #define define_one_rw(_name) \ static struct freq_attr _name = \ __ATTR(_name, 0644, show_##_name, store_##_name) @@ -205,6 +294,7 @@ __ATTR(_name, 0644, show_##_name, store_##_name) define_one_rw(sampling_rate); define_one_rw(up_threshold); define_one_rw(ignore_nice_load); +define_one_rw(powersave_bias); static struct attribute * dbs_attributes[] = { &sampling_rate_max.attr, @@ -212,6 +302,7 @@ static struct attribute * dbs_attributes[] = { &sampling_rate.attr, &up_threshold.attr, &ignore_nice_load.attr, + &powersave_bias.attr, NULL }; @@ -234,6 +325,7 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) if (!this_dbs_info->enable) return; + 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, @@ -274,11 +366,18 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) /* Check for frequency increase */ if (load > dbs_tuners_ins.up_threshold) { /* 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); + if (!dbs_tuners_ins.powersave_bias) { + if (policy->cur == policy->max) + return; + + __cpufreq_driver_target(policy, policy->max, + CPUFREQ_RELATION_H); + } else { + int freq = powersave_bias_target(policy, policy->max, + CPUFREQ_RELATION_H); + __cpufreq_driver_target(policy, freq, + CPUFREQ_RELATION_L); + } return; } @@ -293,14 +392,23 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) * policy. To be safe, we focus 10 points under the threshold. */ if (load < (dbs_tuners_ins.up_threshold - 10)) { - unsigned int freq_next; - freq_next = (policy->cur * load) / + unsigned int freq_next = (policy->cur * load) / (dbs_tuners_ins.up_threshold - 10); - - __cpufreq_driver_target(policy, freq_next, CPUFREQ_RELATION_L); + if (!dbs_tuners_ins.powersave_bias) { + __cpufreq_driver_target(policy, freq_next, + CPUFREQ_RELATION_L); + } else { + int freq = powersave_bias_target(policy, freq_next, + CPUFREQ_RELATION_L); + __cpufreq_driver_target(policy, freq, + CPUFREQ_RELATION_L); + } } } +/* Sampling types */ +enum {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE}; + static void do_dbs_timer(void *data) { unsigned int cpu = smp_processor_id(); @@ -311,10 +419,24 @@ static void do_dbs_timer(void *data) if (!dbs_info->enable) return; - - lock_cpu_hotplug(); - dbs_check_cpu(dbs_info); - unlock_cpu_hotplug(); + /* Common NORMAL_SAMPLE setup */ + INIT_WORK(&dbs_info->work, do_dbs_timer, (void *)DBS_NORMAL_SAMPLE); + if (!dbs_tuners_ins.powersave_bias || + (unsigned long) data == DBS_NORMAL_SAMPLE) { + lock_cpu_hotplug(); + dbs_check_cpu(dbs_info); + unlock_cpu_hotplug(); + if (dbs_info->freq_lo) { + /* Setup timer for SUB_SAMPLE */ + INIT_WORK(&dbs_info->work, do_dbs_timer, + (void *)DBS_SUB_SAMPLE); + delay = dbs_info->freq_hi_jiffies; + } + } else { + __cpufreq_driver_target(dbs_info->cur_policy, + dbs_info->freq_lo, + CPUFREQ_RELATION_H); + } queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay); } @@ -325,6 +447,7 @@ static inline void dbs_timer_init(unsigned int cpu) int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); delay -= jiffies % delay; + ondemand_powersave_bias_init(); INIT_WORK(&dbs_info->work, do_dbs_timer, 0); queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay); } |
