diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq_conservative.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq_conservative.c | 61 |
1 files changed, 20 insertions, 41 deletions
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 7a74d175287..7fc58af748b 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -42,27 +42,12 @@ * this governor will not work. * All times here are in uS. */ -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) -/* Above MIN_SAMPLING_RATE will vanish with its sysfs file soon - * Define the minimal settable sampling rate to the greater of: - * - "HW transition latency" * 100 (same as default sampling / 10) - * - MIN_STAT_SAMPLING_RATE - * To avoid that userspace shoots itself. -*/ -static unsigned int minimum_sampling_rate(void) -{ - return max(def_sampling_rate / 10, MIN_STAT_SAMPLING_RATE); -} -/* This will also vanish soon with removing sampling_rate_max */ -#define MAX_SAMPLING_RATE (500 * def_sampling_rate) +static unsigned int min_sampling_rate; + #define LATENCY_MULTIPLIER (1000) +#define MIN_LATENCY_MULTIPLIER (100) #define DEF_SAMPLING_DOWN_FACTOR (1) #define MAX_SAMPLING_DOWN_FACTOR (10) #define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) @@ -182,27 +167,14 @@ static struct notifier_block dbs_cpufreq_notifier_block = { /************************** sysfs interface ************************/ static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf) { - static int print_once; - - if (!print_once) { - printk(KERN_INFO "CPUFREQ: conservative sampling_rate_max " - "sysfs file is deprecated - used by: %s\n", - current->comm); - print_once = 1; - } - return sprintf(buf, "%u\n", MAX_SAMPLING_RATE); + printk_once(KERN_INFO "CPUFREQ: conservative sampling_rate_max " + "sysfs file is deprecated - used by: %s\n", current->comm); + return sprintf(buf, "%u\n", -1U); } static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf) { - static int print_once; - - if (!print_once) { - printk(KERN_INFO "CPUFREQ: conservative sampling_rate_max " - "sysfs file is deprecated - used by: %s\n", current->comm); - print_once = 1; - } - return sprintf(buf, "%u\n", MIN_SAMPLING_RATE); + return sprintf(buf, "%u\n", min_sampling_rate); } #define define_one_ro(_name) \ @@ -254,7 +226,7 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused, return -EINVAL; mutex_lock(&dbs_mutex); - dbs_tuners_ins.sampling_rate = max(input, minimum_sampling_rate()); + dbs_tuners_ins.sampling_rate = max(input, min_sampling_rate); mutex_unlock(&dbs_mutex); return count; @@ -601,11 +573,18 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, if (latency == 0) latency = 1; - def_sampling_rate = - max(latency * LATENCY_MULTIPLIER, - MIN_STAT_SAMPLING_RATE); - - dbs_tuners_ins.sampling_rate = def_sampling_rate; + /* + * conservative does not implement micro like ondemand + * governor, thus we are bound to jiffes/HZ + */ + min_sampling_rate = + MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10); + /* 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); cpufreq_register_notifier( &dbs_cpufreq_notifier_block, |