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Diffstat (limited to 'drivers/cpufreq/cpufreq_ondemand.c')
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c731
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 "