diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq_ondemand.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq_ondemand.c | 731 |
1 files changed, 229 insertions, 502 deletions
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 396322f2a83f..7731f7c7e79a 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -10,24 +10,23 @@ * published by the Free Software Foundation. */ -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/init.h> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/cpufreq.h> -#include <linux/cpu.h> -#include <linux/jiffies.h> +#include <linux/init.h> +#include <linux/kernel.h> #include <linux/kernel_stat.h> +#include <linux/kobject.h> +#include <linux/module.h> #include <linux/mutex.h> -#include <linux/hrtimer.h> +#include <linux/percpu-defs.h> +#include <linux/sysfs.h> #include <linux/tick.h> -#include <linux/ktime.h> -#include <linux/sched.h> +#include <linux/types.h> -/* - * dbs is used in this file as a shortform for demandbased switching - * It helps to keep variable names smaller, simpler - */ +#include "cpufreq_governor.h" +/* On-demand governor macors */ #define DEF_FREQUENCY_DOWN_DIFFERENTIAL (10) #define DEF_FREQUENCY_UP_THRESHOLD (80) #define DEF_SAMPLING_DOWN_FACTOR (1) @@ -38,80 +37,14 @@ #define MIN_FREQUENCY_UP_THRESHOLD (11) #define MAX_FREQUENCY_UP_THRESHOLD (100) -/* - * 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 - * rate. - * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL) - * this governor will not work. - * All times here are in uS. - */ -#define MIN_SAMPLING_RATE_RATIO (2) - -static unsigned int min_sampling_rate; - -#define LATENCY_MULTIPLIER (1000) -#define MIN_LATENCY_MULTIPLIER (100) -#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) - -static void do_dbs_timer(struct work_struct *work); -static int cpufreq_governor_dbs(struct cpufreq_policy *policy, - unsigned int event); +static struct dbs_data od_dbs_data; +static DEFINE_PER_CPU(struct od_cpu_dbs_info_s, od_cpu_dbs_info); #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND -static +static struct cpufreq_governor cpufreq_gov_ondemand; #endif -struct cpufreq_governor cpufreq_gov_ondemand = { - .name = "ondemand", - .governor = cpufreq_governor_dbs, - .max_transition_latency = TRANSITION_LATENCY_LIMIT, - .owner = THIS_MODULE, -}; -/* Sampling types */ -enum {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE}; - -struct cpu_dbs_info_s { - cputime64_t prev_cpu_idle; - cputime64_t prev_cpu_iowait; - cputime64_t prev_cpu_wall; - cputime64_t prev_cpu_nice; - struct cpufreq_policy *cur_policy; - struct delayed_work work; - struct cpufreq_frequency_table *freq_table; - unsigned int freq_lo; - unsigned int freq_lo_jiffies; - unsigned int freq_hi_jiffies; - unsigned int rate_mult; - int cpu; - unsigned int sample_type:1; - /* - * percpu mutex that serializes governor limit change with - * do_dbs_timer invocation. We do not want do_dbs_timer to run - * when user is changing the governor or limits. - */ - struct mutex timer_mutex; -}; -static DEFINE_PER_CPU(struct cpu_dbs_info_s, od_cpu_dbs_info); - -static unsigned int dbs_enable; /* number of CPUs using this policy */ - -/* - * dbs_mutex protects dbs_enable in governor start/stop. - */ -static DEFINE_MUTEX(dbs_mutex); - -static struct dbs_tuners { - unsigned int sampling_rate; - unsigned int up_threshold; - unsigned int down_differential; - unsigned int ignore_nice; - unsigned int sampling_down_factor; - unsigned int powersave_bias; - unsigned int io_is_busy; -} dbs_tuners_ins = { +static struct od_dbs_tuners od_tuners = { .up_threshold = DEF_FREQUENCY_UP_THRESHOLD, .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR, .down_differential = DEF_FREQUENCY_DOWN_DIFFERENTIAL, @@ -119,48 +52,35 @@ static struct dbs_tuners { .powersave_bias = 0, }; -static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) -{ - u64 idle_time; - u64 cur_wall_time; - u64 busy_time; - - cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); - - busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; - - idle_time = cur_wall_time - busy_time; - if (wall) - *wall = jiffies_to_usecs(cur_wall_time); - - return jiffies_to_usecs(idle_time); -} - -static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall) +static void ondemand_powersave_bias_init_cpu(int cpu) { - u64 idle_time = get_cpu_idle_time_us(cpu, NULL); - - if (idle_time == -1ULL) - return get_cpu_idle_time_jiffy(cpu, wall); - else - idle_time += get_cpu_iowait_time_us(cpu, wall); + struct od_cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, cpu); - return idle_time; + dbs_info->freq_table = cpufreq_frequency_get_table(cpu); + dbs_info->freq_lo = 0; } -static inline cputime64_t get_cpu_iowait_time(unsigned int cpu, cputime64_t *wall) +/* + * Not all CPUs want IO time to be accounted as busy; this depends on how + * efficient idling at a higher frequency/voltage is. + * Pavel Machek says this is not so for various generations of AMD and old + * Intel systems. + * Mike Chan (androidlcom) calis this is also not true for ARM. + * Because of this, whitelist specific known (series) of CPUs by default, and + * leave all others up to the user. + */ +static int should_io_be_busy(void) { - u64 iowait_time = get_cpu_iowait_time_us(cpu, wall); - - if (iowait_time == -1ULL) - return 0; - - return iowait_time; +#if defined(CONFIG_X86) + /* + * For Intel, Core 2 (model 15) andl later have an efficient idle. + */ + if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && + boot_cpu_data.x86 == 6 && + boot_cpu_data.x86_model >= 15) + return 1; +#endif + return 0; } /* @@ -169,14 +89,13 @@ static inline cputime64_t get_cpu_iowait_time(unsigned int cpu, cputime64_t *wal * freq_lo, and freq_lo_jiffies in percpu area for averaging freqs. */ static unsigned int powersave_bias_target(struct cpufreq_policy *policy, - unsigned int freq_next, - unsigned int relation) + 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(od_cpu_dbs_info, + struct od_cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, policy->cpu); if (!dbs_info->freq_table) { @@ -188,7 +107,7 @@ static unsigned int powersave_bias_target(struct cpufreq_policy *policy, 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_reduc = freq_req * od_tuners.powersave_bias / 1000; freq_avg = freq_req - freq_reduc; /* Find freq bounds for freq_avg in freq_table */ @@ -207,7 +126,7 @@ static unsigned int powersave_bias_target(struct cpufreq_policy *policy, dbs_info->freq_lo_jiffies = 0; return freq_lo; } - jiffies_total = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); + jiffies_total = usecs_to_jiffies(od_tuners.sampling_rate); jiffies_hi = (freq_avg - freq_lo) * jiffies_total; jiffies_hi += ((freq_hi - freq_lo) / 2); jiffies_hi /= (freq_hi - freq_lo); @@ -218,13 +137,6 @@ static unsigned int powersave_bias_target(struct cpufreq_policy *policy, return freq_hi; } -static void ondemand_powersave_bias_init_cpu(int cpu) -{ - struct cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, cpu); - dbs_info->freq_table = cpufreq_frequency_get_table(cpu); - dbs_info->freq_lo = 0; -} - static void ondemand_powersave_bias_init(void) { int i; @@ -233,83 +145,173 @@ static void ondemand_powersave_bias_init(void) } } -/************************** sysfs interface ************************/ +static void dbs_freq_increase(struct cpufreq_policy *p, unsigned int freq) +{ + if (od_tuners.powersave_bias) + freq = powersave_bias_target(p, freq, CPUFREQ_RELATION_H); + else if (p->cur == p->max) + return; -static ssize_t show_sampling_rate_min(struct kobject *kobj, - struct attribute *attr, char *buf) + __cpufreq_driver_target(p, freq, od_tuners.powersave_bias ? + CPUFREQ_RELATION_L : CPUFREQ_RELATION_H); +} + +/* + * Every sampling_rate, we check, if current idle time is less than 20% + * (default), then we try to increase frequency Every sampling_rate, 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 + */ +static void od_check_cpu(int cpu, unsigned int load_freq) { - return sprintf(buf, "%u\n", min_sampling_rate); + struct od_cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, cpu); + struct cpufreq_policy *policy = dbs_info->cdbs.cur_policy; + + dbs_info->freq_lo = 0; + + /* Check for frequency increase */ + if (load_freq > od_tuners.up_threshold * policy->cur) { + /* If switching to max speed, apply sampling_down_factor */ + if (policy->cur < policy->max) + dbs_info->rate_mult = + od_tuners.sampling_down_factor; + dbs_freq_increase(policy, policy->max); + return; + } + + /* Check for frequency decrease */ + /* if we cannot reduce the frequency anymore, break out early */ + if (policy->cur == policy->min) + return; + + /* + * The optimal frequency is the frequency that is the lowest that can + * support the current CPU usage without triggering the up policy. To be + * safe, we focus 10 points under the threshold. + */ + if (load_freq < (od_tuners.up_threshold - od_tuners.down_differential) * + policy->cur) { + unsigned int freq_next; + freq_next = load_freq / (od_tuners.up_threshold - + od_tuners.down_differential); + + /* No longer fully busy, reset rate_mult */ + dbs_info->rate_mult = 1; + + if (freq_next < policy->min) + freq_next = policy->min; + + if (!od_tuners.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); + } + } } -define_one_global_ro(sampling_rate_min); +static void od_dbs_timer(struct work_struct *work) +{ + struct od_cpu_dbs_info_s *dbs_info = + container_of(work, struct od_cpu_dbs_info_s, cdbs.work.work); + unsigned int cpu = dbs_info->cdbs.cpu; + int delay, sample_type = dbs_info->sample_type; + + mutex_lock(&dbs_info->cdbs.timer_mutex); + + /* Common NORMAL_SAMPLE setup */ + dbs_info->sample_type = OD_NORMAL_SAMPLE; + if (sample_type == OD_SUB_SAMPLE) { + delay = dbs_info->freq_lo_jiffies; + __cpufreq_driver_target(dbs_info->cdbs.cur_policy, + dbs_info->freq_lo, CPUFREQ_RELATION_H); + } else { + dbs_check_cpu(&od_dbs_data, cpu); + if (dbs_info->freq_lo) { + /* Setup timer for SUB_SAMPLE */ + dbs_info->sample_type = OD_SUB_SAMPLE; + delay = dbs_info->freq_hi_jiffies; + } else { + delay = delay_for_sampling_rate(od_tuners.sampling_rate + * dbs_info->rate_mult); + } + } + + schedule_delayed_work_on(cpu, &dbs_info->cdbs.work, delay); + mutex_unlock(&dbs_info->cdbs.timer_mutex); +} + +/************************** sysfs interface ************************/ -/* cpufreq_ondemand Governor Tunables */ -#define show_one(file_name, object) \ -static ssize_t show_##file_name \ -(struct kobject *kobj, struct attribute *attr, char *buf) \ -{ \ - return sprintf(buf, "%u\n", dbs_tuners_ins.object); \ +static ssize_t show_sampling_rate_min(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return sprintf(buf, "%u\n", od_dbs_data.min_sampling_rate); } -show_one(sampling_rate, sampling_rate); -show_one(io_is_busy, io_is_busy); -show_one(up_threshold, up_threshold); -show_one(sampling_down_factor, sampling_down_factor); -show_one(ignore_nice_load, ignore_nice); -show_one(powersave_bias, powersave_bias); /** * update_sampling_rate - update sampling rate effective immediately if needed. * @new_rate: new sampling rate * * If new rate is smaller than the old, simply updaing - * dbs_tuners_int.sampling_rate might not be appropriate. For example, - * if the original sampling_rate was 1 second and the requested new sampling - * rate is 10 ms because the user needs immediate reaction from ondemand - * governor, but not sure if higher frequency will be required or not, - * then, the governor may change the sampling rate too late; up to 1 second - * later. Thus, if we are reducing the sampling rate, we need to make the - * new value effective immediately. + * dbs_tuners_int.sampling_rate might not be appropriate. For example, if the + * original sampling_rate was 1 second and the requested new sampling rate is 10 + * ms because the user needs immediate reaction from ondemand governor, but not + * sure if higher frequency will be required or not, then, the governor may + * change the sampling rate too late; up to 1 second later. Thus, if we are + * reducing the sampling rate, we need to make the new value effective + * immediately. */ static void update_sampling_rate(unsigned int new_rate) { int cpu; - dbs_tuners_ins.sampling_rate = new_rate - = max(new_rate, min_sampling_rate); + od_tuners.sampling_rate = new_rate = max(new_rate, + od_dbs_data.min_sampling_rate); for_each_online_cpu(cpu) { struct cpufreq_policy *policy; - struct cpu_dbs_info_s *dbs_info; + struct od_cpu_dbs_info_s *dbs_info; unsigned long next_sampling, appointed_at; policy = cpufreq_cpu_get(cpu); if (!policy) continue; + if (policy->governor != &cpufreq_gov_ondemand) { + cpufreq_cpu_put(policy); + continue; + } dbs_info = &per_cpu(od_cpu_dbs_info, policy->cpu); cpufreq_cpu_put(policy); - mutex_lock(&dbs_info->timer_mutex); + mutex_lock(&dbs_info->cdbs.timer_mutex); - if (!delayed_work_pending(&dbs_info->work)) { - mutex_unlock(&dbs_info->timer_mutex); + if (!delayed_work_pending(&dbs_info->cdbs.work)) { + mutex_unlock(&dbs_info->cdbs.timer_mutex); continue; } - next_sampling = jiffies + usecs_to_jiffies(new_rate); - appointed_at = dbs_info->work.timer.expires; - + next_sampling = jiffies + usecs_to_jiffies(new_rate); + appointed_at = dbs_info->cdbs.work.timer.expires; if (time_before(next_sampling, appointed_at)) { - mutex_unlock(&dbs_info->timer_mutex); - cancel_delayed_work_sync(&dbs_info->work); - mutex_lock(&dbs_info->timer_mutex); + mutex_unlock(&dbs_info->cdbs.timer_mutex); + cancel_delayed_work_sync(&dbs_info->cdbs.work); + mutex_lock(&dbs_info->cdbs.timer_mutex); - schedule_delayed_work_on(dbs_info->cpu, &dbs_info->work, - usecs_to_jiffies(new_rate)); + schedule_delayed_work_on(dbs_info->cdbs.cpu, + &dbs_info->cdbs.work, + usecs_to_jiffies(new_rate)); } - mutex_unlock(&dbs_info->timer_mutex); + mutex_unlock(&dbs_info->cdbs.timer_mutex); } } @@ -334,7 +336,7 @@ static ssize_t store_io_is_busy(struct kobject *a, struct attribute *b, ret = sscanf(buf, "%u", &input); if (ret != 1) return -EINVAL; - dbs_tuners_ins.io_is_busy = !!input; + od_tuners.io_is_busy = !!input; return count; } @@ -349,7 +351,7 @@ static ssize_t store_up_threshold(struct kobject *a, struct attribute *b, input < MIN_FREQUENCY_UP_THRESHOLD) { return -EINVAL; } - dbs_tuners_ins.up_threshold = input; + od_tuners.up_threshold = input; return count; } @@ -362,12 +364,12 @@ static ssize_t store_sampling_down_factor(struct kobject *a, if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1) return -EINVAL; - dbs_tuners_ins.sampling_down_factor = input; + od_tuners.sampling_down_factor = input; /* Reset down sampling multiplier in case it was active */ for_each_online_cpu(j) { - struct cpu_dbs_info_s *dbs_info; - dbs_info = &per_cpu(od_cpu_dbs_info, j); + struct od_cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, + j); dbs_info->rate_mult = 1; } return count; @@ -388,19 +390,20 @@ static ssize_t store_ignore_nice_load(struct kobject *a, struct attribute *b, if (input > 1) input = 1; - if (input == dbs_tuners_ins.ignore_nice) { /* nothing to do */ + if (input == od_tuners.ignore_nice) { /* nothing to do */ return count; } - dbs_tuners_ins.ignore_nice = input; + od_tuners.ignore_nice = input; /* we need to re-evaluate prev_cpu_idle */ for_each_online_cpu(j) { - struct cpu_dbs_info_s *dbs_info; + struct od_cpu_dbs_info_s *dbs_info; dbs_info = &per_cpu(od_cpu_dbs_info, j); - dbs_info->prev_cpu_idle = get_cpu_idle_time(j, - &dbs_info->prev_cpu_wall); - if (dbs_tuners_ins.ignore_nice) - dbs_info->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; + dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j, + &dbs_info->cdbs.prev_cpu_wall); + if (od_tuners.ignore_nice) + dbs_info->cdbs.prev_cpu_nice = + kcpustat_cpu(j).cpustat[CPUTIME_NICE]; } return count; @@ -419,17 +422,25 @@ static ssize_t store_powersave_bias(struct kobject *a, struct attribute *b, if (input > 1000) input = 1000; - dbs_tuners_ins.powersave_bias = input; + od_tuners.powersave_bias = input; ondemand_powersave_bias_init(); return count; } +show_one(od, sampling_rate, sampling_rate); +show_one(od, io_is_busy, io_is_busy); +show_one(od, up_threshold, up_threshold); +show_one(od, sampling_down_factor, sampling_down_factor); +show_one(od, ignore_nice_load, ignore_nice); +show_one(od, powersave_bias, powersave_bias); + define_one_global_rw(sampling_rate); define_one_global_rw(io_is_busy); define_one_global_rw(up_threshold); define_one_global_rw(sampling_down_factor); define_one_global_rw(ignore_nice_load); define_one_global_rw(powersave_bias); +define_one_global_ro(sampling_rate_min); static struct attribute *dbs_attributes[] = { &sampling_rate_min.attr, @@ -442,354 +453,71 @@ static struct attribute *dbs_attributes[] = { NULL }; -static struct attribute_group dbs_attr_group = { +static struct attribute_group od_attr_group = { .attrs = dbs_attributes, .name = "ondemand", }; /************************** sysfs end ************************/ -static void dbs_freq_increase(struct cpufreq_policy *p, unsigned int freq) -{ - if (dbs_tuners_ins.powersave_bias) - freq = powersave_bias_target(p, freq, CPUFREQ_RELATION_H); - else if (p->cur == p->max) - return; - - __cpufreq_driver_target(p, freq, dbs_tuners_ins.powersave_bias ? - CPUFREQ_RELATION_L : CPUFREQ_RELATION_H); -} - -static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) -{ - unsigned int max_load_freq; - - struct cpufreq_policy *policy; - unsigned int j; - - this_dbs_info->freq_lo = 0; - 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, 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 - */ - - /* Get Absolute Load - in terms of freq */ - max_load_freq = 0; - - for_each_cpu(j, policy->cpus) { - struct cpu_dbs_info_s *j_dbs_info; - cputime64_t cur_wall_time, cur_idle_time, cur_iowait_time; - unsigned int idle_time, wall_time, iowait_time; - unsigned int load, load_freq; - int freq_avg; - - j_dbs_info = &per_cpu(od_cpu_dbs_info, j); - - cur_idle_time = get_cpu_idle_time(j, &cur_wall_time); - cur_iowait_time = get_cpu_iowait_time(j, &cur_wall_time); - - wall_time = (unsigned int) - (cur_wall_time - j_dbs_info->prev_cpu_wall); - j_dbs_info->prev_cpu_wall = cur_wall_time; - - idle_time = (unsigned int) - (cur_idle_time - j_dbs_info->prev_cpu_idle); - j_dbs_info->prev_cpu_idle = cur_idle_time; - - iowait_time = (unsigned int) - (cur_iowait_time - j_dbs_info->prev_cpu_iowait); - j_dbs_info->prev_cpu_iowait = cur_iowait_time; - - if (dbs_tuners_ins.ignore_nice) { - u64 cur_nice; - unsigned long cur_nice_jiffies; - - cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] - - j_dbs_info->prev_cpu_nice; - /* - * Assumption: nice time between sampling periods will - * be less than 2^32 jiffies for 32 bit sys - */ - cur_nice_jiffies = (unsigned long) - cputime64_to_jiffies64(cur_nice); - - j_dbs_info->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; - idle_time += jiffies_to_usecs(cur_nice_jiffies); - } - - /* - * For the purpose of ondemand, waiting for disk IO is an - * indication that you're performance critical, and not that - * the system is actually idle. So subtract the iowait time - * from the cpu idle time. - */ - - if (dbs_tuners_ins.io_is_busy && idle_time >= iowait_time) - idle_time -= iowait_time; - - if (unlikely(!wall_time || wall_time < idle_time)) - 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; - } +define_get_cpu_dbs_routines(od_cpu_dbs_info); - /* Check for frequency increase */ - if (max_load_freq > dbs_tuners_ins.up_threshold * policy->cur) { - /* If switching to max speed, apply sampling_down_factor */ - if (policy->cur < policy->max) - this_dbs_info->rate_mult = - dbs_tuners_ins.sampling_down_factor; - dbs_freq_increase(policy, policy->max); - return; - } - - /* Check for frequency decrease */ - /* if we cannot reduce the frequency anymore, break out early */ - if (policy->cur == policy->min) - return; - - /* - * The optimal frequency is the frequency that is the lowest that - * can support the current CPU usage without triggering the up - * policy. To be safe, we focus 10 points under the threshold. - */ - if (max_load_freq < - (dbs_tuners_ins.up_threshold - dbs_tuners_ins.down_differential) * - policy->cur) { - unsigned int freq_next; - freq_next = max_load_freq / - (dbs_tuners_ins.up_threshold - - dbs_tuners_ins.down_differential); - - /* No longer fully busy, reset rate_mult */ - this_dbs_info->rate_mult = 1; - - if (freq_next < policy->min) - freq_next = policy->min; - - 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); - } - } -} - -static void do_dbs_timer(struct work_struct *work) -{ - 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; - - int delay; - - mutex_lock(&dbs_info->timer_mutex); - - /* Common NORMAL_SAMPLE setup */ - dbs_info->sample_type = DBS_NORMAL_SAMPLE; - if (!dbs_tuners_ins.powersave_bias || - sample_type == DBS_NORMAL_SAMPLE) { - dbs_check_cpu(dbs_info); - if (dbs_info->freq_lo) { - /* Setup timer for SUB_SAMPLE */ - dbs_info->sample_type = DBS_SUB_SAMPLE; - delay = dbs_info->freq_hi_jiffies; - } else { - /* We want all CPUs to do sampling nearly on - * same jiffy - */ - delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate - * dbs_info->rate_mult); - - if (num_online_cpus() > 1) - delay -= jiffies % delay; - } - } else { - __cpufreq_driver_target(dbs_info->cur_policy, - dbs_info->freq_lo, CPUFREQ_RELATION_H); - delay = dbs_info->freq_lo_jiffies; - } - schedule_delayed_work_on(cpu, &dbs_info->work, delay); - mutex_unlock(&dbs_info->timer_mutex); -} - -static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info) -{ - /* We want all CPUs to do sampling nearly on same jiffy */ - int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); - - if (num_online_cpus() > 1) - delay -= jiffies % delay; +static struct od_ops od_ops = { + .io_busy = should_io_be_busy, + .powersave_bias_init_cpu = ondemand_powersave_bias_init_cpu, + .powersave_bias_target = powersave_bias_target, + .freq_increase = dbs_freq_increase, +}; - dbs_info->sample_type = DBS_NORMAL_SAMPLE; - INIT_DEFERRABLE_WORK(&dbs_info->work, do_dbs_timer); - schedule_delayed_work_on(dbs_info->cpu, &dbs_info->work, delay); -} +static struct dbs_data od_dbs_data = { + .governor = GOV_ONDEMAND, + .attr_group = &od_attr_group, + .tuners = &od_tuners, + .get_cpu_cdbs = get_cpu_cdbs, + .get_cpu_dbs_info_s = get_cpu_dbs_info_s, + .gov_dbs_timer = od_dbs_timer, + .gov_check_cpu = od_check_cpu, + .gov_ops = &od_ops, +}; -static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info) +static int od_cpufreq_governor_dbs(struct cpufreq_policy *policy, + unsigned int event) { - cancel_delayed_work_sync(&dbs_info->work); + return cpufreq_governor_dbs(&od_dbs_data, policy, event); } -/* - * Not all CPUs want IO time to be accounted as busy; this dependson how - * efficient idling at a higher frequency/voltage is. - * Pavel Machek says this is not so for various generations of AMD and old - * Intel systems. - * Mike Chan (androidlcom) calis this is also not true for ARM. - * Because of this, whitelist specific known (series) of CPUs by default, and - * leave all others up to the user. - */ -static int should_io_be_busy(void) -{ -#if defined(CONFIG_X86) - /* - * For Intel, Core 2 (model 15) andl later have an efficient idle. - */ - if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && - boot_cpu_data.x86 == 6 && - boot_cpu_data.x86_model >= 15) - return 1; +#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND +static #endif - return 0; -} - -static int cpufreq_governor_dbs(struct cpufreq_policy *policy, - unsigned int event) -{ - unsigned int cpu = policy->cpu; - struct cpu_dbs_info_s *this_dbs_info; - unsigned int j; - int rc; - - this_dbs_info = &per_cpu(od_cpu_dbs_info, cpu); - - switch (event) { - case CPUFREQ_GOV_START: - if ((!cpu_online(cpu)) || (!policy->cur)) - return -EINVAL; - - mutex_lock(&dbs_mutex); - - dbs_enable++; - for_each_cpu(j, policy->cpus) { - struct cpu_dbs_info_s *j_dbs_info; - j_dbs_info = &per_cpu(od_cpu_dbs_info, j); - j_dbs_info->cur_policy = policy; - - j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j, - &j_dbs_info->prev_cpu_wall); - if (dbs_tuners_ins.ignore_nice) - j_dbs_info->prev_cpu_nice = - kcpustat_cpu(j).cpustat[CPUTIME_NICE]; - } - this_dbs_info->cpu = cpu; - this_dbs_info->rate_mult = 1; - ondemand_powersave_bias_init_cpu(cpu); - /* - * Start the timerschedule work, when this governor - * is used for first time - */ - if (dbs_enable == 1) { - unsigned int latency; - - rc = sysfs_create_group(cpufreq_global_kobject, - &dbs_attr_group); - if (rc) { - mutex_unlock(&dbs_mutex); - return rc; - } - - /* policy latency is in nS. Convert it to uS first */ - latency = policy->cpuinfo.transition_latency / 1000; - if (latency == 0) - latency = 1; - /* Bring kernel and HW constraints together */ - min_sampling_rate = max(min_sampling_rate, - MIN_LATENCY_MULTIPLIER * latency); - dbs_tuners_ins.sampling_rate = - max(min_sampling_rate, - latency * LATENCY_MULTIPLIER); - dbs_tuners_ins.io_is_busy = should_io_be_busy(); - } - mutex_unlock(&dbs_mutex); - - mutex_init(&this_dbs_info->timer_mutex); - dbs_timer_init(this_dbs_info); - break; - - case CPUFREQ_GOV_STOP: - dbs_timer_exit(this_dbs_info); - - mutex_lock(&dbs_mutex); - mutex_destroy(&this_dbs_info->timer_mutex); - dbs_enable--; - mutex_unlock(&dbs_mutex); - if (!dbs_enable) - sysfs_remove_group(cpufreq_global_kobject, - &dbs_attr_group); - - break; - - case CPUFREQ_GOV_LIMITS: - mutex_lock(&this_dbs_info->timer_mutex); - if (policy->max < this_dbs_info->cur_policy->cur) - __cpufreq_driver_target(this_dbs_info->cur_policy, - 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); - dbs_check_cpu(this_dbs_info); - mutex_unlock(&this_dbs_info->timer_mutex); - break; - } - return 0; -} +struct cpufreq_governor cpufreq_gov_ondemand = { + .name = "ondemand", + .governor = od_cpufreq_governor_dbs, + .max_transition_latency = TRANSITION_LATENCY_LIMIT, + .owner = THIS_MODULE, +}; static int __init cpufreq_gov_dbs_init(void) { u64 idle_time; int cpu = get_cpu(); + mutex_init(&od_dbs_data.mutex); idle_time = get_cpu_idle_time_us(cpu, NULL); put_cpu(); if (idle_time != -1ULL) { /* Idle micro accounting is supported. Use finer thresholds */ - dbs_tuners_ins.up_threshold = MICRO_FREQUENCY_UP_THRESHOLD; - dbs_tuners_ins.down_differential = - MICRO_FREQUENCY_DOWN_DIFFERENTIAL; + od_tuners.up_threshold = MICRO_FREQUENCY_UP_THRESHOLD; + od_tuners.down_differential = MICRO_FREQUENCY_DOWN_DIFFERENTIAL; /* * In nohz/micro accounting case we set the minimum frequency * not depending on HZ, but fixed (very low). The deferred * timer might skip some samples if idle/sleeping as needed. */ - min_sampling_rate = MICRO_FREQUENCY_MIN_SAMPLE_RATE; + od_dbs_data.min_sampling_rate = MICRO_FREQUENCY_MIN_SAMPLE_RATE; } else { /* For correct statistics, we need 10 ticks for each measure */ - min_sampling_rate = - MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10); + od_dbs_data.min_sampling_rate = MIN_SAMPLING_RATE_RATIO * + jiffies_to_usecs(10); } return cpufreq_register_governor(&cpufreq_gov_ondemand); @@ -800,7 +528,6 @@ static void __exit cpufreq_gov_dbs_exit(void) cpufreq_unregister_governor(&cpufreq_gov_ondemand); } - MODULE_AUTHOR("Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>"); MODULE_AUTHOR("Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>"); MODULE_DESCRIPTION("'cpufreq_ondemand' - A dynamic cpufreq governor for " |