From 2b03f891ad3804dd3fa4dadfd33e5dcb200389c5 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Sun, 18 Jan 2009 01:43:44 -0500 Subject: [CPUFREQ] checkpatch cleanups for ondemand governor. Signed-off-by: Dave Jones --- drivers/cpufreq/cpufreq_ondemand.c | 29 +++++++++++++---------------- 1 file changed, 13 insertions(+), 16 deletions(-) (limited to 'drivers/cpufreq/cpufreq_ondemand.c') diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 6f45b1658a6..1fa4420eb33 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -65,14 +65,14 @@ 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); @@ -203,12 +203,12 @@ 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); + 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); + return sprintf(buf, "%u\n", MIN_SAMPLING_RATE); } #define define_one_ro(_name) \ @@ -279,14 +279,14 @@ 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; } @@ -337,7 +337,7 @@ 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, @@ -512,8 +512,7 @@ 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); @@ -530,7 +529,7 @@ 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) @@ -617,12 +616,10 @@ 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; } @@ -677,7 +674,7 @@ static void __exit cpufreq_gov_dbs_exit(void) MODULE_AUTHOR("Venkatesh Pallipadi "); MODULE_AUTHOR("Alexey Starikovskiy "); 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 -- cgit v1.2.3-70-g09d2 From 9411b4ef7fcb534fe1582fe02738254e398dd931 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Wed, 4 Feb 2009 11:54:04 +0100 Subject: [CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max} The same info can be obtained via the transition_latency sysfs file Signed-off-by: Thomas Renninger Signed-off-by: Dave Jones --- Documentation/cpu-freq/governors.txt | 10 ++++++++-- drivers/cpufreq/cpufreq_conservative.c | 15 +++++++++++++++ drivers/cpufreq/cpufreq_ondemand.c | 17 +++++++++++++++++ 3 files changed, 40 insertions(+), 2 deletions(-) (limited to 'drivers/cpufreq/cpufreq_ondemand.c') diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt index 5b0cfa67aff..9b1851297d4 100644 --- a/Documentation/cpu-freq/governors.txt +++ b/Documentation/cpu-freq/governors.txt @@ -119,8 +119,14 @@ want the kernel to look at the CPU usage and to make decisions on what to do about the frequency. Typically this is set to values of around '10000' or more. -show_sampling_rate_(min|max): the minimum and maximum sampling rates -available that you may set 'sampling_rate' to. +show_sampling_rate_(min|max): THIS INTERFACE IS DEPRECATED, DON'T USE IT. +You can use wider ranges now and the general +cpuinfo_transition_latency variable (cmp. with user-guide.txt) can be +used to obtain exactly the same info: +show_sampling_rate_min = transtition_latency * 500 / 1000 +show_sampling_rate_max = transtition_latency * 500000 / 1000 +(divided by 1000 is to illustrate that sampling rate is in us and +transition latency is exported ns). up_threshold: defines what the average CPU usage between the samplings of 'sampling_rate' needs to be for the kernel to make a decision on diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index c6b3c6a02fc..0912d7ca8cd 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -140,11 +140,26 @@ 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); } 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); } diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 1fa4420eb33..32ddeaa4224 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -21,6 +21,7 @@ #include #include #include +#include /* * dbs is used in this file as a shortform for demandbased switching @@ -203,11 +204,27 @@ static void ondemand_powersave_bias_init(void) /************************** 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: 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) { + 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); } -- cgit v1.2.3-70-g09d2 From 112124ab0a9f507a0d7fdbb1e1ed2b9a24f8c4ea Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Wed, 4 Feb 2009 11:55:12 +0100 Subject: [CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions Limit sampling rate to transition_latency * 100 or kernel limits. If sampling_rate is tried to be set too low, set the lowest allowed value. Signed-off-by: Thomas Renninger Signed-off-by: Dave Jones --- Documentation/cpu-freq/governors.txt | 14 +++++++++++++- drivers/cpufreq/cpufreq_conservative.c | 28 ++++++++++++++++++---------- drivers/cpufreq/cpufreq_ondemand.c | 28 ++++++++++++++++++---------- 3 files changed, 49 insertions(+), 21 deletions(-) (limited to 'drivers/cpufreq/cpufreq_ondemand.c') diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt index 9b1851297d4..ce73f3eb5dd 100644 --- a/Documentation/cpu-freq/governors.txt +++ b/Documentation/cpu-freq/governors.txt @@ -117,7 +117,19 @@ accessible parameters: sampling_rate: measured in uS (10^-6 seconds), this is how often you want the kernel to look at the CPU usage and to make decisions on what to do about the frequency. Typically this is set to values of -around '10000' or more. +around '10000' or more. It's default value is (cmp. with users-guide.txt): +transition_latency * 1000 +The lowest value you can set is: +transition_latency * 100 or it may get restricted to a value where it +makes not sense for the kernel anymore to poll that often which depends +on your HZ config variable (HZ=1000: max=20000us, HZ=250: max=5000). +Be aware that transition latency is in ns and sampling_rate is in us, so you +get the same sysfs value by default. +Sampling rate should always get adjusted considering the transition latency +To set the sampling rate 750 times as high as the transition latency +in the bash (as said, 1000 is default), do: +echo `$(($(cat cpuinfo_transition_latency) * 750 / 1000)) \ + >ondemand/sampling_rate show_sampling_rate_(min|max): THIS INTERFACE IS DEPRECATED, DON'T USE IT. You can use wider ranges now and the general diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 0912d7ca8cd..8d541c69aec 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -54,8 +54,20 @@ 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 DEF_SAMPLING_DOWN_FACTOR (1) #define MAX_SAMPLING_DOWN_FACTOR (10) #define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) @@ -208,13 +220,11 @@ 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; @@ -540,11 +550,9 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, if (latency == 0) latency = 1; - 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; + def_sampling_rate = + max(10 * latency * LATENCY_MULTIPLIER, + MIN_STAT_SAMPLING_RATE); dbs_tuners_ins.sampling_rate = def_sampling_rate; diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 32ddeaa4224..338f428a15b 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -52,8 +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); @@ -255,13 +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; @@ -607,11 +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; } -- cgit v1.2.3-70-g09d2