Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * drivers/cpufreq/cpufreq_ondemand.c |
| 3 | * |
| 4 | * Copyright (C) 2001 Russell King |
| 5 | * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>. |
| 6 | * Jun Nakajima <jun.nakajima@intel.com> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License version 2 as |
| 10 | * published by the Free Software Foundation. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/init.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/cpufreq.h> |
Andrew Morton | 138a0128 | 2006-06-23 03:31:19 -0700 | [diff] [blame] | 17 | #include <linux/cpu.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <linux/jiffies.h> |
| 19 | #include <linux/kernel_stat.h> |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 20 | #include <linux/mutex.h> |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 21 | #include <linux/hrtimer.h> |
| 22 | #include <linux/tick.h> |
| 23 | #include <linux/ktime.h> |
Thomas Renninger | 9411b4e | 2009-02-04 11:54:04 +0100 | [diff] [blame^] | 24 | #include <linux/sched.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | |
| 26 | /* |
| 27 | * dbs is used in this file as a shortform for demandbased switching |
| 28 | * It helps to keep variable names smaller, simpler |
| 29 | */ |
| 30 | |
venkatesh.pallipadi@intel.com | e9d95bf | 2008-08-04 11:59:10 -0700 | [diff] [blame] | 31 | #define DEF_FREQUENCY_DOWN_DIFFERENTIAL (10) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | #define DEF_FREQUENCY_UP_THRESHOLD (80) |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 33 | #define MICRO_FREQUENCY_DOWN_DIFFERENTIAL (3) |
| 34 | #define MICRO_FREQUENCY_UP_THRESHOLD (95) |
Dave Jones | c29f140 | 2005-05-31 19:03:50 -0700 | [diff] [blame] | 35 | #define MIN_FREQUENCY_UP_THRESHOLD (11) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | #define MAX_FREQUENCY_UP_THRESHOLD (100) |
| 37 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 38 | /* |
| 39 | * The polling frequency of this governor depends on the capability of |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | * the processor. Default polling frequency is 1000 times the transition |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 41 | * latency of the processor. The governor will work on any processor with |
| 42 | * transition latency <= 10mS, using appropriate sampling |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | * rate. |
| 44 | * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL) |
| 45 | * this governor will not work. |
| 46 | * All times here are in uS. |
| 47 | */ |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 48 | static unsigned int def_sampling_rate; |
Dave Jones | df8b59b | 2005-09-20 12:39:35 -0700 | [diff] [blame] | 49 | #define MIN_SAMPLING_RATE_RATIO (2) |
| 50 | /* for correct statistics, we need at least 10 ticks between each measure */ |
Gautham R Shenoy | e08f5f5 | 2006-10-26 16:20:58 +0530 | [diff] [blame] | 51 | #define MIN_STAT_SAMPLING_RATE \ |
| 52 | (MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10)) |
| 53 | #define MIN_SAMPLING_RATE \ |
| 54 | (def_sampling_rate / MIN_SAMPLING_RATE_RATIO) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | #define MAX_SAMPLING_RATE (500 * def_sampling_rate) |
| 56 | #define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (1000) |
Thomas Renninger | 1c25624 | 2007-10-02 13:28:12 -0700 | [diff] [blame] | 57 | #define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 59 | static void do_dbs_timer(struct work_struct *work); |
| 60 | |
| 61 | /* Sampling types */ |
Venkatesh Pallipadi | 529af7a | 2007-02-05 16:12:44 -0800 | [diff] [blame] | 62 | enum {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE}; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | |
| 64 | struct cpu_dbs_info_s { |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 65 | cputime64_t prev_cpu_idle; |
| 66 | cputime64_t prev_cpu_wall; |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 67 | cputime64_t prev_cpu_nice; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 68 | struct cpufreq_policy *cur_policy; |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 69 | struct delayed_work work; |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 70 | struct cpufreq_frequency_table *freq_table; |
| 71 | unsigned int freq_lo; |
| 72 | unsigned int freq_lo_jiffies; |
| 73 | unsigned int freq_hi_jiffies; |
Venkatesh Pallipadi | 529af7a | 2007-02-05 16:12:44 -0800 | [diff] [blame] | 74 | int cpu; |
| 75 | unsigned int enable:1, |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 76 | sample_type:1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | }; |
| 78 | static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info); |
| 79 | |
| 80 | static unsigned int dbs_enable; /* number of CPUs using this policy */ |
| 81 | |
Venkatesh Pallipadi | 4ec223d | 2006-06-21 15:18:34 -0700 | [diff] [blame] | 82 | /* |
| 83 | * DEADLOCK ALERT! There is a ordering requirement between cpu_hotplug |
| 84 | * lock and dbs_mutex. cpu_hotplug lock should always be held before |
| 85 | * dbs_mutex. If any function that can potentially take cpu_hotplug lock |
| 86 | * (like __cpufreq_driver_target()) is being called with dbs_mutex taken, then |
| 87 | * cpu_hotplug lock should be taken before that. Note that cpu_hotplug lock |
| 88 | * is recursive for the same process. -Venki |
| 89 | */ |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 90 | static DEFINE_MUTEX(dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | |
Venkatesh Pallipadi | 2f8a835 | 2006-06-28 13:51:19 -0700 | [diff] [blame] | 92 | static struct workqueue_struct *kondemand_wq; |
Andi Kleen | 6810b54 | 2006-05-08 15:17:31 +0200 | [diff] [blame] | 93 | |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 94 | static struct dbs_tuners { |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 95 | unsigned int sampling_rate; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 96 | unsigned int up_threshold; |
venkatesh.pallipadi@intel.com | e9d95bf | 2008-08-04 11:59:10 -0700 | [diff] [blame] | 97 | unsigned int down_differential; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 98 | unsigned int ignore_nice; |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 99 | unsigned int powersave_bias; |
| 100 | } dbs_tuners_ins = { |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 101 | .up_threshold = DEF_FREQUENCY_UP_THRESHOLD, |
venkatesh.pallipadi@intel.com | e9d95bf | 2008-08-04 11:59:10 -0700 | [diff] [blame] | 102 | .down_differential = DEF_FREQUENCY_DOWN_DIFFERENTIAL, |
Eric Piel | 9cbad61 | 2006-03-10 11:35:27 +0200 | [diff] [blame] | 103 | .ignore_nice = 0, |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 104 | .powersave_bias = 0, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | }; |
| 106 | |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 107 | static inline cputime64_t get_cpu_idle_time_jiffy(unsigned int cpu, |
| 108 | cputime64_t *wall) |
Dave Jones | dac1c1a | 2005-05-31 19:03:49 -0700 | [diff] [blame] | 109 | { |
Venki Pallipadi | ea48761 | 2007-06-20 14:26:24 -0700 | [diff] [blame] | 110 | cputime64_t idle_time; |
venkatesh.pallipadi@intel.com | 3430502 | 2008-08-04 11:59:09 -0700 | [diff] [blame] | 111 | cputime64_t cur_wall_time; |
Venki Pallipadi | ea48761 | 2007-06-20 14:26:24 -0700 | [diff] [blame] | 112 | cputime64_t busy_time; |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 113 | |
venkatesh.pallipadi@intel.com | 3430502 | 2008-08-04 11:59:09 -0700 | [diff] [blame] | 114 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); |
Venki Pallipadi | ea48761 | 2007-06-20 14:26:24 -0700 | [diff] [blame] | 115 | busy_time = cputime64_add(kstat_cpu(cpu).cpustat.user, |
| 116 | kstat_cpu(cpu).cpustat.system); |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 117 | |
Venki Pallipadi | ea48761 | 2007-06-20 14:26:24 -0700 | [diff] [blame] | 118 | busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.irq); |
| 119 | busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.softirq); |
| 120 | busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.steal); |
Venkatesh Pallipadi | 1ca3abd | 2009-01-23 09:25:02 -0500 | [diff] [blame] | 121 | busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.nice); |
Venki Pallipadi | ea48761 | 2007-06-20 14:26:24 -0700 | [diff] [blame] | 122 | |
venkatesh.pallipadi@intel.com | 3430502 | 2008-08-04 11:59:09 -0700 | [diff] [blame] | 123 | idle_time = cputime64_sub(cur_wall_time, busy_time); |
| 124 | if (wall) |
| 125 | *wall = cur_wall_time; |
| 126 | |
Venki Pallipadi | ea48761 | 2007-06-20 14:26:24 -0700 | [diff] [blame] | 127 | return idle_time; |
Dave Jones | dac1c1a | 2005-05-31 19:03:49 -0700 | [diff] [blame] | 128 | } |
| 129 | |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 130 | static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall) |
| 131 | { |
| 132 | u64 idle_time = get_cpu_idle_time_us(cpu, wall); |
| 133 | |
| 134 | if (idle_time == -1ULL) |
| 135 | return get_cpu_idle_time_jiffy(cpu, wall); |
| 136 | |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 137 | return idle_time; |
| 138 | } |
| 139 | |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 140 | /* |
| 141 | * Find right freq to be set now with powersave_bias on. |
| 142 | * Returns the freq_hi to be used right now and will set freq_hi_jiffies, |
| 143 | * freq_lo, and freq_lo_jiffies in percpu area for averaging freqs. |
| 144 | */ |
Adrian Bunk | b5ecf60 | 2006-08-13 23:00:08 +0200 | [diff] [blame] | 145 | static unsigned int powersave_bias_target(struct cpufreq_policy *policy, |
| 146 | unsigned int freq_next, |
| 147 | unsigned int relation) |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 148 | { |
| 149 | unsigned int freq_req, freq_reduc, freq_avg; |
| 150 | unsigned int freq_hi, freq_lo; |
| 151 | unsigned int index = 0; |
| 152 | unsigned int jiffies_total, jiffies_hi, jiffies_lo; |
| 153 | struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, policy->cpu); |
| 154 | |
| 155 | if (!dbs_info->freq_table) { |
| 156 | dbs_info->freq_lo = 0; |
| 157 | dbs_info->freq_lo_jiffies = 0; |
| 158 | return freq_next; |
| 159 | } |
| 160 | |
| 161 | cpufreq_frequency_table_target(policy, dbs_info->freq_table, freq_next, |
| 162 | relation, &index); |
| 163 | freq_req = dbs_info->freq_table[index].frequency; |
| 164 | freq_reduc = freq_req * dbs_tuners_ins.powersave_bias / 1000; |
| 165 | freq_avg = freq_req - freq_reduc; |
| 166 | |
| 167 | /* Find freq bounds for freq_avg in freq_table */ |
| 168 | index = 0; |
| 169 | cpufreq_frequency_table_target(policy, dbs_info->freq_table, freq_avg, |
| 170 | CPUFREQ_RELATION_H, &index); |
| 171 | freq_lo = dbs_info->freq_table[index].frequency; |
| 172 | index = 0; |
| 173 | cpufreq_frequency_table_target(policy, dbs_info->freq_table, freq_avg, |
| 174 | CPUFREQ_RELATION_L, &index); |
| 175 | freq_hi = dbs_info->freq_table[index].frequency; |
| 176 | |
| 177 | /* Find out how long we have to be in hi and lo freqs */ |
| 178 | if (freq_hi == freq_lo) { |
| 179 | dbs_info->freq_lo = 0; |
| 180 | dbs_info->freq_lo_jiffies = 0; |
| 181 | return freq_lo; |
| 182 | } |
| 183 | jiffies_total = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); |
| 184 | jiffies_hi = (freq_avg - freq_lo) * jiffies_total; |
| 185 | jiffies_hi += ((freq_hi - freq_lo) / 2); |
| 186 | jiffies_hi /= (freq_hi - freq_lo); |
| 187 | jiffies_lo = jiffies_total - jiffies_hi; |
| 188 | dbs_info->freq_lo = freq_lo; |
| 189 | dbs_info->freq_lo_jiffies = jiffies_lo; |
| 190 | dbs_info->freq_hi_jiffies = jiffies_hi; |
| 191 | return freq_hi; |
| 192 | } |
| 193 | |
| 194 | static void ondemand_powersave_bias_init(void) |
| 195 | { |
| 196 | int i; |
| 197 | for_each_online_cpu(i) { |
| 198 | struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, i); |
| 199 | dbs_info->freq_table = cpufreq_frequency_get_table(i); |
| 200 | dbs_info->freq_lo = 0; |
| 201 | } |
| 202 | } |
| 203 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 204 | /************************** sysfs interface ************************/ |
| 205 | static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf) |
| 206 | { |
Thomas Renninger | 9411b4e | 2009-02-04 11:54:04 +0100 | [diff] [blame^] | 207 | static int print_once; |
| 208 | |
| 209 | if (!print_once) { |
| 210 | printk(KERN_INFO "CPUFREQ: ondemand sampling_rate_max " |
| 211 | "sysfs file is deprecated - used by: %s\n", |
| 212 | current->comm); |
| 213 | print_once = 1; |
| 214 | } |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 215 | return sprintf(buf, "%u\n", MAX_SAMPLING_RATE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | } |
| 217 | |
| 218 | static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf) |
| 219 | { |
Thomas Renninger | 9411b4e | 2009-02-04 11:54:04 +0100 | [diff] [blame^] | 220 | static int print_once; |
| 221 | |
| 222 | if (!print_once) { |
| 223 | printk(KERN_INFO "CPUFREQ: ondemand sampling_rate_min " |
| 224 | "sysfs file is deprecated - used by: %s\n", |
| 225 | current->comm); |
| 226 | print_once = 1; |
| 227 | } |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 228 | return sprintf(buf, "%u\n", MIN_SAMPLING_RATE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | } |
| 230 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 231 | #define define_one_ro(_name) \ |
| 232 | static struct freq_attr _name = \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | __ATTR(_name, 0444, show_##_name, NULL) |
| 234 | |
| 235 | define_one_ro(sampling_rate_max); |
| 236 | define_one_ro(sampling_rate_min); |
| 237 | |
| 238 | /* cpufreq_ondemand Governor Tunables */ |
| 239 | #define show_one(file_name, object) \ |
| 240 | static ssize_t show_##file_name \ |
| 241 | (struct cpufreq_policy *unused, char *buf) \ |
| 242 | { \ |
| 243 | return sprintf(buf, "%u\n", dbs_tuners_ins.object); \ |
| 244 | } |
| 245 | show_one(sampling_rate, sampling_rate); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | show_one(up_threshold, up_threshold); |
Alexander Clouter | 001893c | 2005-12-01 01:09:25 -0800 | [diff] [blame] | 247 | show_one(ignore_nice_load, ignore_nice); |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 248 | show_one(powersave_bias, powersave_bias); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 250 | static ssize_t store_sampling_rate(struct cpufreq_policy *unused, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | const char *buf, size_t count) |
| 252 | { |
| 253 | unsigned int input; |
| 254 | int ret; |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 255 | ret = sscanf(buf, "%u", &input); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 257 | mutex_lock(&dbs_mutex); |
Gautham R Shenoy | e08f5f5 | 2006-10-26 16:20:58 +0530 | [diff] [blame] | 258 | if (ret != 1 || input > MAX_SAMPLING_RATE |
| 259 | || input < MIN_SAMPLING_RATE) { |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 260 | mutex_unlock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | return -EINVAL; |
| 262 | } |
| 263 | |
| 264 | dbs_tuners_ins.sampling_rate = input; |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 265 | mutex_unlock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | |
| 267 | return count; |
| 268 | } |
| 269 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 270 | static ssize_t store_up_threshold(struct cpufreq_policy *unused, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | const char *buf, size_t count) |
| 272 | { |
| 273 | unsigned int input; |
| 274 | int ret; |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 275 | ret = sscanf(buf, "%u", &input); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 277 | mutex_lock(&dbs_mutex); |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 278 | if (ret != 1 || input > MAX_FREQUENCY_UP_THRESHOLD || |
Dave Jones | c29f140 | 2005-05-31 19:03:50 -0700 | [diff] [blame] | 279 | input < MIN_FREQUENCY_UP_THRESHOLD) { |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 280 | mutex_unlock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | return -EINVAL; |
| 282 | } |
| 283 | |
| 284 | dbs_tuners_ins.up_threshold = input; |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 285 | mutex_unlock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | |
| 287 | return count; |
| 288 | } |
| 289 | |
Alexander Clouter | 001893c | 2005-12-01 01:09:25 -0800 | [diff] [blame] | 290 | static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy, |
Dave Jones | 3d5ee9e | 2005-05-31 19:03:47 -0700 | [diff] [blame] | 291 | const char *buf, size_t count) |
| 292 | { |
| 293 | unsigned int input; |
| 294 | int ret; |
| 295 | |
| 296 | unsigned int j; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 297 | |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 298 | ret = sscanf(buf, "%u", &input); |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 299 | if (ret != 1) |
Dave Jones | 3d5ee9e | 2005-05-31 19:03:47 -0700 | [diff] [blame] | 300 | return -EINVAL; |
| 301 | |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 302 | if (input > 1) |
Dave Jones | 3d5ee9e | 2005-05-31 19:03:47 -0700 | [diff] [blame] | 303 | input = 1; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 304 | |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 305 | mutex_lock(&dbs_mutex); |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 306 | if (input == dbs_tuners_ins.ignore_nice) { /* nothing to do */ |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 307 | mutex_unlock(&dbs_mutex); |
Dave Jones | 3d5ee9e | 2005-05-31 19:03:47 -0700 | [diff] [blame] | 308 | return count; |
| 309 | } |
| 310 | dbs_tuners_ins.ignore_nice = input; |
| 311 | |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 312 | /* we need to re-evaluate prev_cpu_idle */ |
Dave Jones | dac1c1a | 2005-05-31 19:03:49 -0700 | [diff] [blame] | 313 | for_each_online_cpu(j) { |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 314 | struct cpu_dbs_info_s *dbs_info; |
| 315 | dbs_info = &per_cpu(cpu_dbs_info, j); |
venkatesh.pallipadi@intel.com | 3430502 | 2008-08-04 11:59:09 -0700 | [diff] [blame] | 316 | dbs_info->prev_cpu_idle = get_cpu_idle_time(j, |
| 317 | &dbs_info->prev_cpu_wall); |
Venkatesh Pallipadi | 1ca3abd | 2009-01-23 09:25:02 -0500 | [diff] [blame] | 318 | if (dbs_tuners_ins.ignore_nice) |
| 319 | dbs_info->prev_cpu_nice = kstat_cpu(j).cpustat.nice; |
| 320 | |
Dave Jones | 3d5ee9e | 2005-05-31 19:03:47 -0700 | [diff] [blame] | 321 | } |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 322 | mutex_unlock(&dbs_mutex); |
Dave Jones | 3d5ee9e | 2005-05-31 19:03:47 -0700 | [diff] [blame] | 323 | |
| 324 | return count; |
| 325 | } |
| 326 | |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 327 | static ssize_t store_powersave_bias(struct cpufreq_policy *unused, |
| 328 | const char *buf, size_t count) |
| 329 | { |
| 330 | unsigned int input; |
| 331 | int ret; |
| 332 | ret = sscanf(buf, "%u", &input); |
| 333 | |
| 334 | if (ret != 1) |
| 335 | return -EINVAL; |
| 336 | |
| 337 | if (input > 1000) |
| 338 | input = 1000; |
| 339 | |
| 340 | mutex_lock(&dbs_mutex); |
| 341 | dbs_tuners_ins.powersave_bias = input; |
| 342 | ondemand_powersave_bias_init(); |
| 343 | mutex_unlock(&dbs_mutex); |
| 344 | |
| 345 | return count; |
| 346 | } |
| 347 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | #define define_one_rw(_name) \ |
| 349 | static struct freq_attr _name = \ |
| 350 | __ATTR(_name, 0644, show_##_name, store_##_name) |
| 351 | |
| 352 | define_one_rw(sampling_rate); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | define_one_rw(up_threshold); |
Alexander Clouter | 001893c | 2005-12-01 01:09:25 -0800 | [diff] [blame] | 354 | define_one_rw(ignore_nice_load); |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 355 | define_one_rw(powersave_bias); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 357 | static struct attribute *dbs_attributes[] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | &sampling_rate_max.attr, |
| 359 | &sampling_rate_min.attr, |
| 360 | &sampling_rate.attr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | &up_threshold.attr, |
Alexander Clouter | 001893c | 2005-12-01 01:09:25 -0800 | [diff] [blame] | 362 | &ignore_nice_load.attr, |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 363 | &powersave_bias.attr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | NULL |
| 365 | }; |
| 366 | |
| 367 | static struct attribute_group dbs_attr_group = { |
| 368 | .attrs = dbs_attributes, |
| 369 | .name = "ondemand", |
| 370 | }; |
| 371 | |
| 372 | /************************** sysfs end ************************/ |
| 373 | |
Venkatesh Pallipadi | 2f8a835 | 2006-06-28 13:51:19 -0700 | [diff] [blame] | 374 | static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | { |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 376 | unsigned int max_load_freq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | |
| 378 | struct cpufreq_policy *policy; |
| 379 | unsigned int j; |
| 380 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 381 | if (!this_dbs_info->enable) |
| 382 | return; |
| 383 | |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 384 | this_dbs_info->freq_lo = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 385 | policy = this_dbs_info->cur_policy; |
Venki Pallipadi | ea48761 | 2007-06-20 14:26:24 -0700 | [diff] [blame] | 386 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 387 | /* |
Dave Jones | c29f140 | 2005-05-31 19:03:50 -0700 | [diff] [blame] | 388 | * Every sampling_rate, we check, if current idle time is less |
| 389 | * than 20% (default), then we try to increase frequency |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 390 | * Every sampling_rate, we look for a the lowest |
Dave Jones | c29f140 | 2005-05-31 19:03:50 -0700 | [diff] [blame] | 391 | * frequency which can sustain the load while keeping idle time over |
| 392 | * 30%. If such a frequency exist, we try to decrease to this frequency. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | * |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 394 | * Any frequency increase takes it to the maximum frequency. |
| 395 | * Frequency reduction happens at minimum steps of |
| 396 | * 5% (default) of current frequency |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | */ |
| 398 | |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 399 | /* Get Absolute Load - in terms of freq */ |
| 400 | max_load_freq = 0; |
| 401 | |
Rusty Russell | 835481d | 2009-01-04 05:18:06 -0800 | [diff] [blame] | 402 | for_each_cpu(j, policy->cpus) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 403 | struct cpu_dbs_info_s *j_dbs_info; |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 404 | cputime64_t cur_wall_time, cur_idle_time; |
| 405 | unsigned int idle_time, wall_time; |
| 406 | unsigned int load, load_freq; |
| 407 | int freq_avg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | j_dbs_info = &per_cpu(cpu_dbs_info, j); |
venkatesh.pallipadi@intel.com | 3430502 | 2008-08-04 11:59:09 -0700 | [diff] [blame] | 410 | |
| 411 | cur_idle_time = get_cpu_idle_time(j, &cur_wall_time); |
| 412 | |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 413 | wall_time = (unsigned int) cputime64_sub(cur_wall_time, |
| 414 | j_dbs_info->prev_cpu_wall); |
| 415 | j_dbs_info->prev_cpu_wall = cur_wall_time; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 416 | |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 417 | idle_time = (unsigned int) cputime64_sub(cur_idle_time, |
| 418 | j_dbs_info->prev_cpu_idle); |
| 419 | j_dbs_info->prev_cpu_idle = cur_idle_time; |
| 420 | |
Venkatesh Pallipadi | 1ca3abd | 2009-01-23 09:25:02 -0500 | [diff] [blame] | 421 | if (dbs_tuners_ins.ignore_nice) { |
| 422 | cputime64_t cur_nice; |
| 423 | unsigned long cur_nice_jiffies; |
| 424 | |
| 425 | cur_nice = cputime64_sub(kstat_cpu(j).cpustat.nice, |
| 426 | j_dbs_info->prev_cpu_nice); |
| 427 | /* |
| 428 | * Assumption: nice time between sampling periods will |
| 429 | * be less than 2^32 jiffies for 32 bit sys |
| 430 | */ |
| 431 | cur_nice_jiffies = (unsigned long) |
| 432 | cputime64_to_jiffies64(cur_nice); |
| 433 | |
| 434 | j_dbs_info->prev_cpu_nice = kstat_cpu(j).cpustat.nice; |
| 435 | idle_time += jiffies_to_usecs(cur_nice_jiffies); |
| 436 | } |
| 437 | |
venkatesh.pallipadi@intel.com | 3430502 | 2008-08-04 11:59:09 -0700 | [diff] [blame] | 438 | if (unlikely(!wall_time || wall_time < idle_time)) |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 439 | continue; |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 440 | |
| 441 | load = 100 * (wall_time - idle_time) / wall_time; |
| 442 | |
| 443 | freq_avg = __cpufreq_driver_getavg(policy, j); |
| 444 | if (freq_avg <= 0) |
| 445 | freq_avg = policy->cur; |
| 446 | |
| 447 | load_freq = load * freq_avg; |
| 448 | if (load_freq > max_load_freq) |
| 449 | max_load_freq = load_freq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | } |
| 451 | |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 452 | /* Check for frequency increase */ |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 453 | if (max_load_freq > dbs_tuners_ins.up_threshold * policy->cur) { |
Dave Jones | c11420a | 2005-05-31 19:03:48 -0700 | [diff] [blame] | 454 | /* if we are already at full speed then break out early */ |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 455 | if (!dbs_tuners_ins.powersave_bias) { |
| 456 | if (policy->cur == policy->max) |
| 457 | return; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 458 | |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 459 | __cpufreq_driver_target(policy, policy->max, |
| 460 | CPUFREQ_RELATION_H); |
| 461 | } else { |
| 462 | int freq = powersave_bias_target(policy, policy->max, |
| 463 | CPUFREQ_RELATION_H); |
| 464 | __cpufreq_driver_target(policy, freq, |
| 465 | CPUFREQ_RELATION_L); |
| 466 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | return; |
| 468 | } |
| 469 | |
| 470 | /* Check for frequency decrease */ |
Dave Jones | c29f140 | 2005-05-31 19:03:50 -0700 | [diff] [blame] | 471 | /* if we cannot reduce the frequency anymore, break out early */ |
| 472 | if (policy->cur == policy->min) |
| 473 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | |
Dave Jones | c29f140 | 2005-05-31 19:03:50 -0700 | [diff] [blame] | 475 | /* |
| 476 | * The optimal frequency is the frequency that is the lowest that |
| 477 | * can support the current CPU usage without triggering the up |
| 478 | * policy. To be safe, we focus 10 points under the threshold. |
| 479 | */ |
venkatesh.pallipadi@intel.com | e9d95bf | 2008-08-04 11:59:10 -0700 | [diff] [blame] | 480 | if (max_load_freq < |
| 481 | (dbs_tuners_ins.up_threshold - dbs_tuners_ins.down_differential) * |
| 482 | policy->cur) { |
venkatesh.pallipadi@intel.com | c43aa3b | 2008-08-04 11:59:08 -0700 | [diff] [blame] | 483 | unsigned int freq_next; |
venkatesh.pallipadi@intel.com | e9d95bf | 2008-08-04 11:59:10 -0700 | [diff] [blame] | 484 | freq_next = max_load_freq / |
| 485 | (dbs_tuners_ins.up_threshold - |
| 486 | dbs_tuners_ins.down_differential); |
Venkatesh Pallipadi | dfde5d6 | 2006-10-03 12:38:45 -0700 | [diff] [blame] | 487 | |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 488 | if (!dbs_tuners_ins.powersave_bias) { |
| 489 | __cpufreq_driver_target(policy, freq_next, |
| 490 | CPUFREQ_RELATION_L); |
| 491 | } else { |
| 492 | int freq = powersave_bias_target(policy, freq_next, |
| 493 | CPUFREQ_RELATION_L); |
| 494 | __cpufreq_driver_target(policy, freq, |
| 495 | CPUFREQ_RELATION_L); |
| 496 | } |
Venkatesh Pallipadi | ccb2fe2 | 2006-06-28 13:49:52 -0700 | [diff] [blame] | 497 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | } |
| 499 | |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 500 | static void do_dbs_timer(struct work_struct *work) |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 501 | { |
Venkatesh Pallipadi | 529af7a | 2007-02-05 16:12:44 -0800 | [diff] [blame] | 502 | struct cpu_dbs_info_s *dbs_info = |
| 503 | container_of(work, struct cpu_dbs_info_s, work.work); |
| 504 | unsigned int cpu = dbs_info->cpu; |
| 505 | int sample_type = dbs_info->sample_type; |
| 506 | |
Alexey Starikovskiy | 1ce28d6 | 2006-07-31 22:25:20 +0400 | [diff] [blame] | 507 | /* We want all CPUs to do sampling nearly on same jiffy */ |
| 508 | int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 509 | |
Alexey Starikovskiy | 1ce28d6 | 2006-07-31 22:25:20 +0400 | [diff] [blame] | 510 | delay -= jiffies % delay; |
Venkatesh Pallipadi | 2f8a835 | 2006-06-28 13:51:19 -0700 | [diff] [blame] | 511 | |
Venkatesh Pallipadi | 56463b7 | 2007-02-05 16:12:45 -0800 | [diff] [blame] | 512 | if (lock_policy_rwsem_write(cpu) < 0) |
Linus Torvalds | 2cd7cbd | 2006-07-23 12:05:00 -0700 | [diff] [blame] | 513 | return; |
Venkatesh Pallipadi | 56463b7 | 2007-02-05 16:12:45 -0800 | [diff] [blame] | 514 | |
| 515 | if (!dbs_info->enable) { |
| 516 | unlock_policy_rwsem_write(cpu); |
| 517 | return; |
| 518 | } |
| 519 | |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 520 | /* Common NORMAL_SAMPLE setup */ |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 521 | dbs_info->sample_type = DBS_NORMAL_SAMPLE; |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 522 | if (!dbs_tuners_ins.powersave_bias || |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 523 | sample_type == DBS_NORMAL_SAMPLE) { |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 524 | dbs_check_cpu(dbs_info); |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 525 | if (dbs_info->freq_lo) { |
| 526 | /* Setup timer for SUB_SAMPLE */ |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 527 | dbs_info->sample_type = DBS_SUB_SAMPLE; |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 528 | delay = dbs_info->freq_hi_jiffies; |
| 529 | } |
| 530 | } else { |
| 531 | __cpufreq_driver_target(dbs_info->cur_policy, |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 532 | dbs_info->freq_lo, CPUFREQ_RELATION_H); |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 533 | } |
Alexey Starikovskiy | 1ce28d6 | 2006-07-31 22:25:20 +0400 | [diff] [blame] | 534 | queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay); |
Venkatesh Pallipadi | 56463b7 | 2007-02-05 16:12:45 -0800 | [diff] [blame] | 535 | unlock_policy_rwsem_write(cpu); |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 536 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | |
Venkatesh Pallipadi | 529af7a | 2007-02-05 16:12:44 -0800 | [diff] [blame] | 538 | static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 539 | { |
Alexey Starikovskiy | 1ce28d6 | 2006-07-31 22:25:20 +0400 | [diff] [blame] | 540 | /* We want all CPUs to do sampling nearly on same jiffy */ |
| 541 | int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); |
| 542 | delay -= jiffies % delay; |
Venkatesh Pallipadi | 2f8a835 | 2006-06-28 13:51:19 -0700 | [diff] [blame] | 543 | |
Dave Jones | c18a148 | 2007-02-10 20:03:51 -0500 | [diff] [blame] | 544 | dbs_info->enable = 1; |
Alexey Starikovskiy | 05ca035 | 2006-07-31 22:28:12 +0400 | [diff] [blame] | 545 | ondemand_powersave_bias_init(); |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 546 | dbs_info->sample_type = DBS_NORMAL_SAMPLE; |
Venki Pallipadi | 2828703 | 2007-05-08 00:27:47 -0700 | [diff] [blame] | 547 | INIT_DELAYED_WORK_DEFERRABLE(&dbs_info->work, do_dbs_timer); |
Venkatesh Pallipadi | 529af7a | 2007-02-05 16:12:44 -0800 | [diff] [blame] | 548 | queue_delayed_work_on(dbs_info->cpu, kondemand_wq, &dbs_info->work, |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 549 | delay); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 550 | } |
| 551 | |
Linus Torvalds | 2cd7cbd | 2006-07-23 12:05:00 -0700 | [diff] [blame] | 552 | static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 553 | { |
Linus Torvalds | 2cd7cbd | 2006-07-23 12:05:00 -0700 | [diff] [blame] | 554 | dbs_info->enable = 0; |
| 555 | cancel_delayed_work(&dbs_info->work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | } |
| 557 | |
| 558 | static int cpufreq_governor_dbs(struct cpufreq_policy *policy, |
| 559 | unsigned int event) |
| 560 | { |
| 561 | unsigned int cpu = policy->cpu; |
| 562 | struct cpu_dbs_info_s *this_dbs_info; |
| 563 | unsigned int j; |
Jeff Garzik | 914f7c3 | 2006-10-20 14:31:00 -0700 | [diff] [blame] | 564 | int rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 565 | |
| 566 | this_dbs_info = &per_cpu(cpu_dbs_info, cpu); |
| 567 | |
| 568 | switch (event) { |
| 569 | case CPUFREQ_GOV_START: |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 570 | if ((!cpu_online(cpu)) || (!policy->cur)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 571 | return -EINVAL; |
| 572 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | if (this_dbs_info->enable) /* Already enabled */ |
| 574 | break; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 575 | |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 576 | mutex_lock(&dbs_mutex); |
Venkatesh Pallipadi | 2f8a835 | 2006-06-28 13:51:19 -0700 | [diff] [blame] | 577 | dbs_enable++; |
Jeff Garzik | 914f7c3 | 2006-10-20 14:31:00 -0700 | [diff] [blame] | 578 | |
| 579 | rc = sysfs_create_group(&policy->kobj, &dbs_attr_group); |
| 580 | if (rc) { |
Jeff Garzik | 914f7c3 | 2006-10-20 14:31:00 -0700 | [diff] [blame] | 581 | dbs_enable--; |
| 582 | mutex_unlock(&dbs_mutex); |
| 583 | return rc; |
| 584 | } |
| 585 | |
Rusty Russell | 835481d | 2009-01-04 05:18:06 -0800 | [diff] [blame] | 586 | for_each_cpu(j, policy->cpus) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | struct cpu_dbs_info_s *j_dbs_info; |
| 588 | j_dbs_info = &per_cpu(cpu_dbs_info, j); |
| 589 | j_dbs_info->cur_policy = policy; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 590 | |
venkatesh.pallipadi@intel.com | 3430502 | 2008-08-04 11:59:09 -0700 | [diff] [blame] | 591 | j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j, |
| 592 | &j_dbs_info->prev_cpu_wall); |
Venkatesh Pallipadi | 1ca3abd | 2009-01-23 09:25:02 -0500 | [diff] [blame] | 593 | if (dbs_tuners_ins.ignore_nice) { |
| 594 | j_dbs_info->prev_cpu_nice = |
| 595 | kstat_cpu(j).cpustat.nice; |
| 596 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 597 | } |
Venkatesh Pallipadi | 529af7a | 2007-02-05 16:12:44 -0800 | [diff] [blame] | 598 | this_dbs_info->cpu = cpu; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | /* |
| 600 | * Start the timerschedule work, when this governor |
| 601 | * is used for first time |
| 602 | */ |
| 603 | if (dbs_enable == 1) { |
| 604 | unsigned int latency; |
| 605 | /* policy latency is in nS. Convert it to uS first */ |
Dave Jones | df8b59b | 2005-09-20 12:39:35 -0700 | [diff] [blame] | 606 | latency = policy->cpuinfo.transition_latency / 1000; |
| 607 | if (latency == 0) |
| 608 | latency = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | |
Dave Jones | df8b59b | 2005-09-20 12:39:35 -0700 | [diff] [blame] | 610 | def_sampling_rate = latency * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | DEF_SAMPLING_RATE_LATENCY_MULTIPLIER; |
Dave Jones | df8b59b | 2005-09-20 12:39:35 -0700 | [diff] [blame] | 612 | |
| 613 | if (def_sampling_rate < MIN_STAT_SAMPLING_RATE) |
| 614 | def_sampling_rate = MIN_STAT_SAMPLING_RATE; |
| 615 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | dbs_tuners_ins.sampling_rate = def_sampling_rate; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | } |
Venkatesh Pallipadi | 529af7a | 2007-02-05 16:12:44 -0800 | [diff] [blame] | 618 | dbs_timer_init(this_dbs_info); |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 619 | |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 620 | mutex_unlock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | break; |
| 622 | |
| 623 | case CPUFREQ_GOV_STOP: |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 624 | mutex_lock(&dbs_mutex); |
Linus Torvalds | 2cd7cbd | 2006-07-23 12:05:00 -0700 | [diff] [blame] | 625 | dbs_timer_exit(this_dbs_info); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | sysfs_remove_group(&policy->kobj, &dbs_attr_group); |
| 627 | dbs_enable--; |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 628 | mutex_unlock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | |
| 630 | break; |
| 631 | |
| 632 | case CPUFREQ_GOV_LIMITS: |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 633 | mutex_lock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | if (policy->max < this_dbs_info->cur_policy->cur) |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 635 | __cpufreq_driver_target(this_dbs_info->cur_policy, |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 636 | policy->max, CPUFREQ_RELATION_H); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 637 | else if (policy->min > this_dbs_info->cur_policy->cur) |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 638 | __cpufreq_driver_target(this_dbs_info->cur_policy, |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 639 | policy->min, CPUFREQ_RELATION_L); |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 640 | mutex_unlock(&dbs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | break; |
| 642 | } |
| 643 | return 0; |
| 644 | } |
| 645 | |
Sven Wegener | c4d14bc | 2008-09-20 16:50:08 +0200 | [diff] [blame] | 646 | #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND |
| 647 | static |
| 648 | #endif |
Thomas Renninger | 1c25624 | 2007-10-02 13:28:12 -0700 | [diff] [blame] | 649 | struct cpufreq_governor cpufreq_gov_ondemand = { |
| 650 | .name = "ondemand", |
| 651 | .governor = cpufreq_governor_dbs, |
| 652 | .max_transition_latency = TRANSITION_LATENCY_LIMIT, |
| 653 | .owner = THIS_MODULE, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 654 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | |
| 656 | static int __init cpufreq_gov_dbs_init(void) |
| 657 | { |
Akinobu Mita | 888a794 | 2008-07-14 12:00:45 +0900 | [diff] [blame] | 658 | int err; |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 659 | cputime64_t wall; |
Andrea Righi | 4f6e6b9 | 2008-09-18 10:43:40 +0000 | [diff] [blame] | 660 | u64 idle_time; |
| 661 | int cpu = get_cpu(); |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 662 | |
Andrea Righi | 4f6e6b9 | 2008-09-18 10:43:40 +0000 | [diff] [blame] | 663 | idle_time = get_cpu_idle_time_us(cpu, &wall); |
| 664 | put_cpu(); |
venkatesh.pallipadi@intel.com | 8080091 | 2008-08-04 11:59:12 -0700 | [diff] [blame] | 665 | if (idle_time != -1ULL) { |
| 666 | /* Idle micro accounting is supported. Use finer thresholds */ |
| 667 | dbs_tuners_ins.up_threshold = MICRO_FREQUENCY_UP_THRESHOLD; |
| 668 | dbs_tuners_ins.down_differential = |
| 669 | MICRO_FREQUENCY_DOWN_DIFFERENTIAL; |
| 670 | } |
Akinobu Mita | 888a794 | 2008-07-14 12:00:45 +0900 | [diff] [blame] | 671 | |
Venkatesh Pallipadi | 56463b7 | 2007-02-05 16:12:45 -0800 | [diff] [blame] | 672 | kondemand_wq = create_workqueue("kondemand"); |
| 673 | if (!kondemand_wq) { |
| 674 | printk(KERN_ERR "Creation of kondemand failed\n"); |
| 675 | return -EFAULT; |
| 676 | } |
Akinobu Mita | 888a794 | 2008-07-14 12:00:45 +0900 | [diff] [blame] | 677 | err = cpufreq_register_governor(&cpufreq_gov_ondemand); |
| 678 | if (err) |
| 679 | destroy_workqueue(kondemand_wq); |
| 680 | |
| 681 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 682 | } |
| 683 | |
| 684 | static void __exit cpufreq_gov_dbs_exit(void) |
| 685 | { |
Thomas Renninger | 1c25624 | 2007-10-02 13:28:12 -0700 | [diff] [blame] | 686 | cpufreq_unregister_governor(&cpufreq_gov_ondemand); |
Venkatesh Pallipadi | 56463b7 | 2007-02-05 16:12:45 -0800 | [diff] [blame] | 687 | destroy_workqueue(kondemand_wq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 688 | } |
| 689 | |
| 690 | |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 691 | MODULE_AUTHOR("Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>"); |
| 692 | MODULE_AUTHOR("Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>"); |
| 693 | MODULE_DESCRIPTION("'cpufreq_ondemand' - A dynamic cpufreq governor for " |
Dave Jones | 2b03f89 | 2009-01-18 01:43:44 -0500 | [diff] [blame] | 694 | "Low Latency Frequency Transition capable processors"); |
Venkatesh Pallipadi | ffac80e | 2006-06-28 13:52:18 -0700 | [diff] [blame] | 695 | MODULE_LICENSE("GPL"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | |
Johannes Weiner | 6915719 | 2008-01-17 15:21:08 -0800 | [diff] [blame] | 697 | #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND |
| 698 | fs_initcall(cpufreq_gov_dbs_init); |
| 699 | #else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | module_init(cpufreq_gov_dbs_init); |
Johannes Weiner | 6915719 | 2008-01-17 15:21:08 -0800 | [diff] [blame] | 701 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | module_exit(cpufreq_gov_dbs_exit); |