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Diffstat (limited to 'drivers/cpufreq/cpufreq_ondemand.c')
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c121
1 files changed, 73 insertions, 48 deletions
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index 6a2b036c938..338f428a15b 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -21,6 +21,7 @@
#include <linux/hrtimer.h>
#include <linux/tick.h>
#include <linux/ktime.h>
+#include <linux/sched.h>
/*
* dbs is used in this file as a shortform for demandbased switching
@@ -51,8 +52,20 @@ static unsigned int def_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)
-#define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (1000)
+#define LATENCY_MULTIPLIER (1000)
#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
static void do_dbs_timer(struct work_struct *work);
@@ -65,14 +78,14 @@ struct cpu_dbs_info_s {
cputime64_t prev_cpu_wall;
cputime64_t prev_cpu_nice;
struct cpufreq_policy *cur_policy;
- struct delayed_work work;
+ struct delayed_work work;
struct cpufreq_frequency_table *freq_table;
unsigned int freq_lo;
unsigned int freq_lo_jiffies;
unsigned int freq_hi_jiffies;
int cpu;
unsigned int enable:1,
- sample_type:1;
+ sample_type:1;
};
static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
@@ -117,11 +130,7 @@ static inline cputime64_t get_cpu_idle_time_jiffy(unsigned int cpu,
busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.irq);
busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.softirq);
busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.steal);
-
- if (!dbs_tuners_ins.ignore_nice) {
- busy_time = cputime64_add(busy_time,
- kstat_cpu(cpu).cpustat.nice);
- }
+ busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.nice);
idle_time = cputime64_sub(cur_wall_time, busy_time);
if (wall)
@@ -137,23 +146,6 @@ static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
if (idle_time == -1ULL)
return get_cpu_idle_time_jiffy(cpu, wall);
- if (dbs_tuners_ins.ignore_nice) {
- cputime64_t cur_nice;
- unsigned long cur_nice_jiffies;
- struct cpu_dbs_info_s *dbs_info;
-
- dbs_info = &per_cpu(cpu_dbs_info, cpu);
- cur_nice = cputime64_sub(kstat_cpu(cpu).cpustat.nice,
- 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);
- dbs_info->prev_cpu_nice = kstat_cpu(cpu).cpustat.nice;
- return idle_time + jiffies_to_usecs(cur_nice_jiffies);
- }
return idle_time;
}
@@ -224,12 +216,28 @@ static void ondemand_powersave_bias_init(void)
/************************** sysfs interface ************************/
static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf)
{
- return sprintf (buf, "%u\n", MAX_SAMPLING_RATE);
+ static int print_once;
+
+ if (!print_once) {
+ printk(KERN_INFO "CPUFREQ: ondemand sampling_rate_max "
+ "sysfs file is deprecated - used by: %s\n",
+ current->comm);
+ print_once = 1;
+ }
+ return sprintf(buf, "%u\n", MAX_SAMPLING_RATE);
}
static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf)
{
- return sprintf (buf, "%u\n", MIN_SAMPLING_RATE);
+ static int print_once;
+
+ if (!print_once) {
+ printk(KERN_INFO "CPUFREQ: ondemand sampling_rate_min "
+ "sysfs file is deprecated - used by: %s\n",
+ current->comm);
+ print_once = 1;
+ }
+ return sprintf(buf, "%u\n", MIN_SAMPLING_RATE);
}
#define define_one_ro(_name) \
@@ -259,13 +267,11 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
ret = sscanf(buf, "%u", &input);
mutex_lock(&dbs_mutex);
- if (ret != 1 || input > MAX_SAMPLING_RATE
- || input < MIN_SAMPLING_RATE) {
+ if (ret != 1) {
mutex_unlock(&dbs_mutex);
return -EINVAL;
}
-
- dbs_tuners_ins.sampling_rate = input;
+ dbs_tuners_ins.sampling_rate = max(input, minimum_sampling_rate());
mutex_unlock(&dbs_mutex);
return count;
@@ -300,14 +306,14 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
unsigned int j;
ret = sscanf(buf, "%u", &input);
- if ( ret != 1 )
+ if (ret != 1)
return -EINVAL;
- if ( input > 1 )
+ if (input > 1)
input = 1;
mutex_lock(&dbs_mutex);
- if ( input == dbs_tuners_ins.ignore_nice ) { /* nothing to do */
+ if (input == dbs_tuners_ins.ignore_nice) { /* nothing to do */
mutex_unlock(&dbs_mutex);
return count;
}
@@ -319,6 +325,9 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
dbs_info = &per_cpu(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 = kstat_cpu(j).cpustat.nice;
+
}
mutex_unlock(&dbs_mutex);
@@ -355,7 +364,7 @@ define_one_rw(up_threshold);
define_one_rw(ignore_nice_load);
define_one_rw(powersave_bias);
-static struct attribute * dbs_attributes[] = {
+static struct attribute *dbs_attributes[] = {
&sampling_rate_max.attr,
&sampling_rate_min.attr,
&sampling_rate.attr,
@@ -419,6 +428,23 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
j_dbs_info->prev_cpu_idle);
j_dbs_info->prev_cpu_idle = cur_idle_time;
+ if (dbs_tuners_ins.ignore_nice) {
+ cputime64_t cur_nice;
+ unsigned long cur_nice_jiffies;
+
+ cur_nice = cputime64_sub(kstat_cpu(j).cpustat.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 = kstat_cpu(j).cpustat.nice;
+ idle_time += jiffies_to_usecs(cur_nice_jiffies);
+ }
+
if (unlikely(!wall_time || wall_time < idle_time))
continue;
@@ -513,8 +539,7 @@ static void do_dbs_timer(struct work_struct *work)
}
} else {
__cpufreq_driver_target(dbs_info->cur_policy,
- dbs_info->freq_lo,
- CPUFREQ_RELATION_H);
+ dbs_info->freq_lo, CPUFREQ_RELATION_H);
}
queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay);
unlock_policy_rwsem_write(cpu);
@@ -531,7 +556,7 @@ static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info)
dbs_info->sample_type = DBS_NORMAL_SAMPLE;
INIT_DELAYED_WORK_DEFERRABLE(&dbs_info->work, do_dbs_timer);
queue_delayed_work_on(dbs_info->cpu, kondemand_wq, &dbs_info->work,
- delay);
+ delay);
}
static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info)
@@ -575,6 +600,10 @@ static int cpufreq_governor_dbs(struct cpufreq_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 =
+ kstat_cpu(j).cpustat.nice;
+ }
}
this_dbs_info->cpu = cpu;
/*
@@ -588,11 +617,9 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
if (latency == 0)
latency = 1;
- def_sampling_rate = latency *
- DEF_SAMPLING_RATE_LATENCY_MULTIPLIER;
-
- if (def_sampling_rate < MIN_STAT_SAMPLING_RATE)
- def_sampling_rate = MIN_STAT_SAMPLING_RATE;
+ def_sampling_rate =
+ max(latency * LATENCY_MULTIPLIER,
+ MIN_STAT_SAMPLING_RATE);
dbs_tuners_ins.sampling_rate = def_sampling_rate;
}
@@ -614,12 +641,10 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
mutex_lock(&dbs_mutex);
if (policy->max < this_dbs_info->cur_policy->cur)
__cpufreq_driver_target(this_dbs_info->cur_policy,
- policy->max,
- CPUFREQ_RELATION_H);
+ 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);
+ policy->min, CPUFREQ_RELATION_L);
mutex_unlock(&dbs_mutex);
break;
}
@@ -674,7 +699,7 @@ static void __exit cpufreq_gov_dbs_exit(void)
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 "
- "Low Latency Frequency Transition capable processors");
+ "Low Latency Frequency Transition capable processors");
MODULE_LICENSE("GPL");
#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-25 17:54:21 +0000