X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fcpufreq%2Fcpufreq_conservative.c;h=e07a35487bde7cf5b713c0c203a4819a537ae901;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=e1df376e709ea0681c0498e1cc5c548764748cab;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index e1df376e7..e07a35487 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -28,19 +28,14 @@ #include #include #include - +#include /* * dbs is used in this file as a shortform for demandbased switching * It helps to keep variable names smaller, simpler */ #define DEF_FREQUENCY_UP_THRESHOLD (80) -#define MIN_FREQUENCY_UP_THRESHOLD (0) -#define MAX_FREQUENCY_UP_THRESHOLD (100) - #define DEF_FREQUENCY_DOWN_THRESHOLD (20) -#define MIN_FREQUENCY_DOWN_THRESHOLD (0) -#define MAX_FREQUENCY_DOWN_THRESHOLD (100) /* * The polling frequency of this governor depends on the capability of @@ -53,10 +48,14 @@ * All times here are in uS. */ static unsigned int def_sampling_rate; -#define MIN_SAMPLING_RATE (def_sampling_rate / 2) +#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 MAX_SAMPLING_RATE (500 * def_sampling_rate) -#define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (100000) -#define DEF_SAMPLING_DOWN_FACTOR (5) +#define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (1000) +#define DEF_SAMPLING_DOWN_FACTOR (1) +#define MAX_SAMPLING_DOWN_FACTOR (10) #define TRANSITION_LATENCY_LIMIT (10 * 1000) static void do_dbs_timer(void *data); @@ -66,12 +65,14 @@ struct cpu_dbs_info_s { unsigned int prev_cpu_idle_up; unsigned int prev_cpu_idle_down; unsigned int enable; + unsigned int down_skip; + unsigned int requested_freq; }; static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info); static unsigned int dbs_enable; /* number of CPUs using this policy */ -static DECLARE_MUTEX (dbs_sem); +static DEFINE_MUTEX (dbs_mutex); static DECLARE_WORK (dbs_work, do_dbs_timer, NULL); struct dbs_tuners { @@ -87,13 +88,15 @@ static struct dbs_tuners dbs_tuners_ins = { .up_threshold = DEF_FREQUENCY_UP_THRESHOLD, .down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD, .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR, + .ignore_nice = 0, + .freq_step = 5, }; static inline unsigned int get_cpu_idle_time(unsigned int cpu) { return kstat_cpu(cpu).cpustat.idle + kstat_cpu(cpu).cpustat.iowait + - ( !dbs_tuners_ins.ignore_nice ? + ( dbs_tuners_ins.ignore_nice ? kstat_cpu(cpu).cpustat.nice : 0); } @@ -127,7 +130,7 @@ show_one(sampling_rate, sampling_rate); show_one(sampling_down_factor, sampling_down_factor); show_one(up_threshold, up_threshold); show_one(down_threshold, down_threshold); -show_one(ignore_nice, ignore_nice); +show_one(ignore_nice_load, ignore_nice); show_one(freq_step, freq_step); static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused, @@ -136,12 +139,12 @@ static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused, unsigned int input; int ret; ret = sscanf (buf, "%u", &input); - if (ret != 1 ) + if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1) return -EINVAL; - down(&dbs_sem); + mutex_lock(&dbs_mutex); dbs_tuners_ins.sampling_down_factor = input; - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return count; } @@ -153,14 +156,14 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused, int ret; ret = sscanf (buf, "%u", &input); - down(&dbs_sem); + mutex_lock(&dbs_mutex); if (ret != 1 || input > MAX_SAMPLING_RATE || input < MIN_SAMPLING_RATE) { - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return -EINVAL; } dbs_tuners_ins.sampling_rate = input; - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return count; } @@ -172,16 +175,14 @@ static ssize_t store_up_threshold(struct cpufreq_policy *unused, int ret; ret = sscanf (buf, "%u", &input); - down(&dbs_sem); - if (ret != 1 || input > MAX_FREQUENCY_UP_THRESHOLD || - input < MIN_FREQUENCY_UP_THRESHOLD || - input <= dbs_tuners_ins.down_threshold) { - up(&dbs_sem); + mutex_lock(&dbs_mutex); + if (ret != 1 || input > 100 || input <= dbs_tuners_ins.down_threshold) { + mutex_unlock(&dbs_mutex); return -EINVAL; } dbs_tuners_ins.up_threshold = input; - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return count; } @@ -193,21 +194,19 @@ static ssize_t store_down_threshold(struct cpufreq_policy *unused, int ret; ret = sscanf (buf, "%u", &input); - down(&dbs_sem); - if (ret != 1 || input > MAX_FREQUENCY_DOWN_THRESHOLD || - input < MIN_FREQUENCY_DOWN_THRESHOLD || - input >= dbs_tuners_ins.up_threshold) { - up(&dbs_sem); + mutex_lock(&dbs_mutex); + if (ret != 1 || input > 100 || input >= dbs_tuners_ins.up_threshold) { + mutex_unlock(&dbs_mutex); return -EINVAL; } dbs_tuners_ins.down_threshold = input; - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return count; } -static ssize_t store_ignore_nice(struct cpufreq_policy *policy, +static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy, const char *buf, size_t count) { unsigned int input; @@ -222,9 +221,9 @@ static ssize_t store_ignore_nice(struct cpufreq_policy *policy, if ( input > 1 ) input = 1; - down(&dbs_sem); + mutex_lock(&dbs_mutex); if ( input == dbs_tuners_ins.ignore_nice ) { /* nothing to do */ - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return count; } dbs_tuners_ins.ignore_nice = input; @@ -236,7 +235,7 @@ static ssize_t store_ignore_nice(struct cpufreq_policy *policy, j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j); j_dbs_info->prev_cpu_idle_down = j_dbs_info->prev_cpu_idle_up; } - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return count; } @@ -257,9 +256,9 @@ static ssize_t store_freq_step(struct cpufreq_policy *policy, /* no need to test here if freq_step is zero as the user might actually * want this, they would be crazy though :) */ - down(&dbs_sem); + mutex_lock(&dbs_mutex); dbs_tuners_ins.freq_step = input; - up(&dbs_sem); + mutex_unlock(&dbs_mutex); return count; } @@ -272,7 +271,7 @@ define_one_rw(sampling_rate); define_one_rw(sampling_down_factor); define_one_rw(up_threshold); define_one_rw(down_threshold); -define_one_rw(ignore_nice); +define_one_rw(ignore_nice_load); define_one_rw(freq_step); static struct attribute * dbs_attributes[] = { @@ -282,7 +281,7 @@ static struct attribute * dbs_attributes[] = { &sampling_down_factor.attr, &up_threshold.attr, &down_threshold.attr, - &ignore_nice.attr, + &ignore_nice_load.attr, &freq_step.attr, NULL }; @@ -297,31 +296,17 @@ static struct attribute_group dbs_attr_group = { static void dbs_check_cpu(int cpu) { unsigned int idle_ticks, up_idle_ticks, down_idle_ticks; + unsigned int tmp_idle_ticks, total_idle_ticks; unsigned int freq_step; unsigned int freq_down_sampling_rate; - static int down_skip[NR_CPUS]; - static int requested_freq[NR_CPUS]; - static unsigned short init_flag = 0; - struct cpu_dbs_info_s *this_dbs_info; - struct cpu_dbs_info_s *dbs_info; - + struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cpu_dbs_info, cpu); struct cpufreq_policy *policy; - unsigned int j; - this_dbs_info = &per_cpu(cpu_dbs_info, cpu); if (!this_dbs_info->enable) return; policy = this_dbs_info->cur_policy; - if ( init_flag == 0 ) { - for ( /* NULL */; init_flag < NR_CPUS; init_flag++ ) { - dbs_info = &per_cpu(cpu_dbs_info, init_flag); - requested_freq[cpu] = dbs_info->cur_policy->cur; - } - init_flag = 1; - } - /* * The default safe range is 20% to 80% * Every sampling_rate, we check @@ -337,39 +322,29 @@ static void dbs_check_cpu(int cpu) */ /* Check for frequency increase */ - idle_ticks = UINT_MAX; - for_each_cpu_mask(j, policy->cpus) { - unsigned int tmp_idle_ticks, total_idle_ticks; - struct cpu_dbs_info_s *j_dbs_info; - j_dbs_info = &per_cpu(cpu_dbs_info, j); - /* Check for frequency increase */ - total_idle_ticks = get_cpu_idle_time(j); - tmp_idle_ticks = total_idle_ticks - - j_dbs_info->prev_cpu_idle_up; - j_dbs_info->prev_cpu_idle_up = total_idle_ticks; - - if (tmp_idle_ticks < idle_ticks) - idle_ticks = tmp_idle_ticks; - } + /* Check for frequency increase */ + total_idle_ticks = get_cpu_idle_time(cpu); + tmp_idle_ticks = total_idle_ticks - + this_dbs_info->prev_cpu_idle_up; + this_dbs_info->prev_cpu_idle_up = total_idle_ticks; + + if (tmp_idle_ticks < idle_ticks) + idle_ticks = tmp_idle_ticks; /* Scale idle ticks by 100 and compare with up and down ticks */ idle_ticks *= 100; up_idle_ticks = (100 - dbs_tuners_ins.up_threshold) * - usecs_to_jiffies(dbs_tuners_ins.sampling_rate); + usecs_to_jiffies(dbs_tuners_ins.sampling_rate); if (idle_ticks < up_idle_ticks) { - down_skip[cpu] = 0; - for_each_cpu_mask(j, policy->cpus) { - struct cpu_dbs_info_s *j_dbs_info; + this_dbs_info->down_skip = 0; + this_dbs_info->prev_cpu_idle_down = + this_dbs_info->prev_cpu_idle_up; - j_dbs_info = &per_cpu(cpu_dbs_info, j); - j_dbs_info->prev_cpu_idle_down = - j_dbs_info->prev_cpu_idle_up; - } /* if we are already at full speed then break out early */ - if (requested_freq[cpu] == policy->max) + if (this_dbs_info->requested_freq == policy->max) return; freq_step = (dbs_tuners_ins.freq_step * policy->max) / 100; @@ -378,49 +353,45 @@ static void dbs_check_cpu(int cpu) if (unlikely(freq_step == 0)) freq_step = 5; - requested_freq[cpu] += freq_step; - if (requested_freq[cpu] > policy->max) - requested_freq[cpu] = policy->max; + this_dbs_info->requested_freq += freq_step; + if (this_dbs_info->requested_freq > policy->max) + this_dbs_info->requested_freq = policy->max; - __cpufreq_driver_target(policy, requested_freq[cpu], + __cpufreq_driver_target(policy, this_dbs_info->requested_freq, CPUFREQ_RELATION_H); return; } /* Check for frequency decrease */ - down_skip[cpu]++; - if (down_skip[cpu] < dbs_tuners_ins.sampling_down_factor) + this_dbs_info->down_skip++; + if (this_dbs_info->down_skip < dbs_tuners_ins.sampling_down_factor) return; - idle_ticks = UINT_MAX; - for_each_cpu_mask(j, policy->cpus) { - unsigned int tmp_idle_ticks, total_idle_ticks; - struct cpu_dbs_info_s *j_dbs_info; + /* Check for frequency decrease */ + total_idle_ticks = this_dbs_info->prev_cpu_idle_up; + tmp_idle_ticks = total_idle_ticks - + this_dbs_info->prev_cpu_idle_down; + this_dbs_info->prev_cpu_idle_down = total_idle_ticks; - j_dbs_info = &per_cpu(cpu_dbs_info, j); - total_idle_ticks = j_dbs_info->prev_cpu_idle_up; - tmp_idle_ticks = total_idle_ticks - - j_dbs_info->prev_cpu_idle_down; - j_dbs_info->prev_cpu_idle_down = total_idle_ticks; - - if (tmp_idle_ticks < idle_ticks) - idle_ticks = tmp_idle_ticks; - } + if (tmp_idle_ticks < idle_ticks) + idle_ticks = tmp_idle_ticks; /* Scale idle ticks by 100 and compare with up and down ticks */ idle_ticks *= 100; - down_skip[cpu] = 0; + this_dbs_info->down_skip = 0; freq_down_sampling_rate = dbs_tuners_ins.sampling_rate * dbs_tuners_ins.sampling_down_factor; down_idle_ticks = (100 - dbs_tuners_ins.down_threshold) * - usecs_to_jiffies(freq_down_sampling_rate); + usecs_to_jiffies(freq_down_sampling_rate); if (idle_ticks > down_idle_ticks) { - /* if we are already at the lowest speed then break out early + /* + * if we are already at the lowest speed then break out early * or if we 'cannot' reduce the speed as the user might want - * freq_step to be zero */ - if (requested_freq[cpu] == policy->min + * freq_step to be zero + */ + if (this_dbs_info->requested_freq == policy->min || dbs_tuners_ins.freq_step == 0) return; @@ -430,13 +401,12 @@ static void dbs_check_cpu(int cpu) if (unlikely(freq_step == 0)) freq_step = 5; - requested_freq[cpu] -= freq_step; - if (requested_freq[cpu] < policy->min) - requested_freq[cpu] = policy->min; + this_dbs_info->requested_freq -= freq_step; + if (this_dbs_info->requested_freq < policy->min) + this_dbs_info->requested_freq = policy->min; - __cpufreq_driver_target(policy, - requested_freq[cpu], - CPUFREQ_RELATION_H); + __cpufreq_driver_target(policy, this_dbs_info->requested_freq, + CPUFREQ_RELATION_H); return; } } @@ -444,12 +414,12 @@ static void dbs_check_cpu(int cpu) static void do_dbs_timer(void *data) { int i; - down(&dbs_sem); + mutex_lock(&dbs_mutex); for_each_online_cpu(i) dbs_check_cpu(i); schedule_delayed_work(&dbs_work, usecs_to_jiffies(dbs_tuners_ins.sampling_rate)); - up(&dbs_sem); + mutex_unlock(&dbs_mutex); } static inline void dbs_timer_init(void) @@ -487,17 +457,19 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, if (this_dbs_info->enable) /* Already enabled */ break; - down(&dbs_sem); + mutex_lock(&dbs_mutex); 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->cur_policy = policy; - j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j); + j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(cpu); j_dbs_info->prev_cpu_idle_down = j_dbs_info->prev_cpu_idle_up; } this_dbs_info->enable = 1; + this_dbs_info->down_skip = 0; + this_dbs_info->requested_freq = policy->cur; sysfs_create_group(&policy->kobj, &dbs_attr_group); dbs_enable++; /* @@ -507,25 +479,26 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, if (dbs_enable == 1) { unsigned int latency; /* policy latency is in nS. Convert it to uS first */ + latency = policy->cpuinfo.transition_latency / 1000; + if (latency == 0) + latency = 1; - latency = policy->cpuinfo.transition_latency; - if (latency < 1000) - latency = 1000; - - def_sampling_rate = (latency / 1000) * + def_sampling_rate = 10 * latency * DEF_SAMPLING_RATE_LATENCY_MULTIPLIER; + + if (def_sampling_rate < MIN_STAT_SAMPLING_RATE) + def_sampling_rate = MIN_STAT_SAMPLING_RATE; + dbs_tuners_ins.sampling_rate = def_sampling_rate; - dbs_tuners_ins.ignore_nice = 0; - dbs_tuners_ins.freq_step = 5; dbs_timer_init(); } - up(&dbs_sem); + mutex_unlock(&dbs_mutex); break; case CPUFREQ_GOV_STOP: - down(&dbs_sem); + mutex_lock(&dbs_mutex); this_dbs_info->enable = 0; sysfs_remove_group(&policy->kobj, &dbs_attr_group); dbs_enable--; @@ -536,12 +509,12 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, if (dbs_enable == 0) dbs_timer_exit(); - up(&dbs_sem); + mutex_unlock(&dbs_mutex); break; case CPUFREQ_GOV_LIMITS: - down(&dbs_sem); + mutex_lock(&dbs_mutex); if (policy->max < this_dbs_info->cur_policy->cur) __cpufreq_driver_target( this_dbs_info->cur_policy, @@ -550,7 +523,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, __cpufreq_driver_target( this_dbs_info->cur_policy, policy->min, CPUFREQ_RELATION_L); - up(&dbs_sem); + mutex_unlock(&dbs_mutex); break; } return 0;