Commit | Line | Data |
---|---|---|
2aacdfff | 1 | /* |
2 | * drivers/cpufreq/cpufreq_governor.c | |
3 | * | |
4 | * CPUFREQ governors common code | |
5 | * | |
4471a34f VK |
6 | * Copyright (C) 2001 Russell King |
7 | * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>. | |
8 | * (C) 2003 Jun Nakajima <jun.nakajima@intel.com> | |
9 | * (C) 2009 Alexander Clouter <alex@digriz.org.uk> | |
10 | * (c) 2012 Viresh Kumar <viresh.kumar@linaro.org> | |
11 | * | |
2aacdfff | 12 | * This program is free software; you can redistribute it and/or modify |
13 | * it under the terms of the GNU General Public License version 2 as | |
14 | * published by the Free Software Foundation. | |
15 | */ | |
16 | ||
4471a34f VK |
17 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
18 | ||
2aacdfff | 19 | #include <asm/cputime.h> |
4471a34f VK |
20 | #include <linux/cpufreq.h> |
21 | #include <linux/cpumask.h> | |
2aacdfff | 22 | #include <linux/export.h> |
23 | #include <linux/kernel_stat.h> | |
4471a34f | 24 | #include <linux/mutex.h> |
4d5dcc42 | 25 | #include <linux/slab.h> |
2aacdfff | 26 | #include <linux/tick.h> |
27 | #include <linux/types.h> | |
4471a34f | 28 | #include <linux/workqueue.h> |
2f7021a8 | 29 | #include <linux/cpu.h> |
4471a34f VK |
30 | |
31 | #include "cpufreq_governor.h" | |
32 | ||
4d5dcc42 VK |
33 | static struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
34 | { | |
35 | if (have_governor_per_policy()) | |
36 | return &policy->kobj; | |
37 | else | |
38 | return cpufreq_global_kobject; | |
39 | } | |
40 | ||
41 | static struct attribute_group *get_sysfs_attr(struct dbs_data *dbs_data) | |
42 | { | |
43 | if (have_governor_per_policy()) | |
44 | return dbs_data->cdata->attr_group_gov_pol; | |
45 | else | |
46 | return dbs_data->cdata->attr_group_gov_sys; | |
47 | } | |
48 | ||
2aacdfff | 49 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
50 | { | |
51 | u64 idle_time; | |
52 | u64 cur_wall_time; | |
53 | u64 busy_time; | |
54 | ||
55 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
56 | ||
57 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
58 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
59 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
60 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
61 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
62 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
63 | ||
64 | idle_time = cur_wall_time - busy_time; | |
65 | if (wall) | |
a0e5af3c | 66 | *wall = cputime_to_usecs(cur_wall_time); |
2aacdfff | 67 | |
a0e5af3c | 68 | return cputime_to_usecs(idle_time); |
2aacdfff | 69 | } |
70 | ||
9366d840 | 71 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) |
2aacdfff | 72 | { |
9366d840 | 73 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); |
2aacdfff | 74 | |
75 | if (idle_time == -1ULL) | |
76 | return get_cpu_idle_time_jiffy(cpu, wall); | |
9366d840 | 77 | else if (!io_busy) |
2aacdfff | 78 | idle_time += get_cpu_iowait_time_us(cpu, wall); |
79 | ||
80 | return idle_time; | |
81 | } | |
82 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
4471a34f VK |
83 | |
84 | void dbs_check_cpu(struct dbs_data *dbs_data, int cpu) | |
85 | { | |
4d5dcc42 | 86 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f VK |
87 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; |
88 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
89 | struct cpufreq_policy *policy; | |
90 | unsigned int max_load = 0; | |
91 | unsigned int ignore_nice; | |
92 | unsigned int j; | |
93 | ||
4d5dcc42 | 94 | if (dbs_data->cdata->governor == GOV_ONDEMAND) |
4471a34f VK |
95 | ignore_nice = od_tuners->ignore_nice; |
96 | else | |
97 | ignore_nice = cs_tuners->ignore_nice; | |
98 | ||
99 | policy = cdbs->cur_policy; | |
100 | ||
101 | /* Get Absolute Load (in terms of freq for ondemand gov) */ | |
102 | for_each_cpu(j, policy->cpus) { | |
103 | struct cpu_dbs_common_info *j_cdbs; | |
9366d840 SK |
104 | u64 cur_wall_time, cur_idle_time; |
105 | unsigned int idle_time, wall_time; | |
4471a34f | 106 | unsigned int load; |
9366d840 | 107 | int io_busy = 0; |
4471a34f | 108 | |
4d5dcc42 | 109 | j_cdbs = dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f | 110 | |
9366d840 SK |
111 | /* |
112 | * For the purpose of ondemand, waiting for disk IO is | |
113 | * an indication that you're performance critical, and | |
114 | * not that the system is actually idle. So do not add | |
115 | * the iowait time to the cpu idle time. | |
116 | */ | |
117 | if (dbs_data->cdata->governor == GOV_ONDEMAND) | |
118 | io_busy = od_tuners->io_is_busy; | |
119 | cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy); | |
4471a34f VK |
120 | |
121 | wall_time = (unsigned int) | |
122 | (cur_wall_time - j_cdbs->prev_cpu_wall); | |
123 | j_cdbs->prev_cpu_wall = cur_wall_time; | |
124 | ||
125 | idle_time = (unsigned int) | |
126 | (cur_idle_time - j_cdbs->prev_cpu_idle); | |
127 | j_cdbs->prev_cpu_idle = cur_idle_time; | |
128 | ||
129 | if (ignore_nice) { | |
130 | u64 cur_nice; | |
131 | unsigned long cur_nice_jiffies; | |
132 | ||
133 | cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] - | |
134 | cdbs->prev_cpu_nice; | |
135 | /* | |
136 | * Assumption: nice time between sampling periods will | |
137 | * be less than 2^32 jiffies for 32 bit sys | |
138 | */ | |
139 | cur_nice_jiffies = (unsigned long) | |
140 | cputime64_to_jiffies64(cur_nice); | |
141 | ||
142 | cdbs->prev_cpu_nice = | |
143 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
144 | idle_time += jiffies_to_usecs(cur_nice_jiffies); | |
145 | } | |
146 | ||
4471a34f VK |
147 | if (unlikely(!wall_time || wall_time < idle_time)) |
148 | continue; | |
149 | ||
150 | load = 100 * (wall_time - idle_time) / wall_time; | |
151 | ||
4d5dcc42 | 152 | if (dbs_data->cdata->governor == GOV_ONDEMAND) { |
4471a34f VK |
153 | int freq_avg = __cpufreq_driver_getavg(policy, j); |
154 | if (freq_avg <= 0) | |
155 | freq_avg = policy->cur; | |
156 | ||
157 | load *= freq_avg; | |
158 | } | |
159 | ||
160 | if (load > max_load) | |
161 | max_load = load; | |
162 | } | |
163 | ||
4d5dcc42 | 164 | dbs_data->cdata->gov_check_cpu(cpu, max_load); |
4471a34f VK |
165 | } |
166 | EXPORT_SYMBOL_GPL(dbs_check_cpu); | |
167 | ||
031299b3 VK |
168 | static inline void __gov_queue_work(int cpu, struct dbs_data *dbs_data, |
169 | unsigned int delay) | |
4471a34f | 170 | { |
4d5dcc42 | 171 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f | 172 | |
031299b3 | 173 | mod_delayed_work_on(cpu, system_wq, &cdbs->work, delay); |
4471a34f VK |
174 | } |
175 | ||
031299b3 VK |
176 | void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, |
177 | unsigned int delay, bool all_cpus) | |
4471a34f | 178 | { |
031299b3 VK |
179 | int i; |
180 | ||
181 | if (!all_cpus) { | |
182 | __gov_queue_work(smp_processor_id(), dbs_data, delay); | |
183 | } else { | |
2f7021a8 | 184 | get_online_cpus(); |
031299b3 VK |
185 | for_each_cpu(i, policy->cpus) |
186 | __gov_queue_work(i, dbs_data, delay); | |
2f7021a8 | 187 | put_online_cpus(); |
031299b3 VK |
188 | } |
189 | } | |
190 | EXPORT_SYMBOL_GPL(gov_queue_work); | |
191 | ||
192 | static inline void gov_cancel_work(struct dbs_data *dbs_data, | |
193 | struct cpufreq_policy *policy) | |
194 | { | |
195 | struct cpu_dbs_common_info *cdbs; | |
196 | int i; | |
58ddcead | 197 | |
031299b3 VK |
198 | for_each_cpu(i, policy->cpus) { |
199 | cdbs = dbs_data->cdata->get_cpu_cdbs(i); | |
200 | cancel_delayed_work_sync(&cdbs->work); | |
201 | } | |
4471a34f VK |
202 | } |
203 | ||
4447266b VK |
204 | /* Will return if we need to evaluate cpu load again or not */ |
205 | bool need_load_eval(struct cpu_dbs_common_info *cdbs, | |
206 | unsigned int sampling_rate) | |
207 | { | |
208 | if (policy_is_shared(cdbs->cur_policy)) { | |
209 | ktime_t time_now = ktime_get(); | |
210 | s64 delta_us = ktime_us_delta(time_now, cdbs->time_stamp); | |
211 | ||
212 | /* Do nothing if we recently have sampled */ | |
213 | if (delta_us < (s64)(sampling_rate / 2)) | |
214 | return false; | |
215 | else | |
216 | cdbs->time_stamp = time_now; | |
217 | } | |
218 | ||
219 | return true; | |
220 | } | |
221 | EXPORT_SYMBOL_GPL(need_load_eval); | |
222 | ||
4d5dcc42 VK |
223 | static void set_sampling_rate(struct dbs_data *dbs_data, |
224 | unsigned int sampling_rate) | |
225 | { | |
226 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
227 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
228 | cs_tuners->sampling_rate = sampling_rate; | |
229 | } else { | |
230 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; | |
231 | od_tuners->sampling_rate = sampling_rate; | |
232 | } | |
233 | } | |
234 | ||
235 | int cpufreq_governor_dbs(struct cpufreq_policy *policy, | |
236 | struct common_dbs_data *cdata, unsigned int event) | |
4471a34f | 237 | { |
4d5dcc42 | 238 | struct dbs_data *dbs_data; |
4471a34f VK |
239 | struct od_cpu_dbs_info_s *od_dbs_info = NULL; |
240 | struct cs_cpu_dbs_info_s *cs_dbs_info = NULL; | |
8eeed095 | 241 | struct od_ops *od_ops = NULL; |
4d5dcc42 VK |
242 | struct od_dbs_tuners *od_tuners = NULL; |
243 | struct cs_dbs_tuners *cs_tuners = NULL; | |
4471a34f | 244 | struct cpu_dbs_common_info *cpu_cdbs; |
4d5dcc42 | 245 | unsigned int sampling_rate, latency, ignore_nice, j, cpu = policy->cpu; |
9366d840 | 246 | int io_busy = 0; |
4471a34f VK |
247 | int rc; |
248 | ||
4d5dcc42 VK |
249 | if (have_governor_per_policy()) |
250 | dbs_data = policy->governor_data; | |
251 | else | |
252 | dbs_data = cdata->gdbs_data; | |
253 | ||
254 | WARN_ON(!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT)); | |
255 | ||
256 | switch (event) { | |
257 | case CPUFREQ_GOV_POLICY_INIT: | |
258 | if (have_governor_per_policy()) { | |
259 | WARN_ON(dbs_data); | |
260 | } else if (dbs_data) { | |
a97c98ad | 261 | dbs_data->usage_count++; |
4d5dcc42 VK |
262 | policy->governor_data = dbs_data; |
263 | return 0; | |
264 | } | |
265 | ||
266 | dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL); | |
267 | if (!dbs_data) { | |
268 | pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__); | |
269 | return -ENOMEM; | |
270 | } | |
271 | ||
272 | dbs_data->cdata = cdata; | |
a97c98ad | 273 | dbs_data->usage_count = 1; |
4d5dcc42 VK |
274 | rc = cdata->init(dbs_data); |
275 | if (rc) { | |
276 | pr_err("%s: POLICY_INIT: init() failed\n", __func__); | |
277 | kfree(dbs_data); | |
278 | return rc; | |
279 | } | |
280 | ||
281 | rc = sysfs_create_group(get_governor_parent_kobj(policy), | |
282 | get_sysfs_attr(dbs_data)); | |
283 | if (rc) { | |
284 | cdata->exit(dbs_data); | |
285 | kfree(dbs_data); | |
286 | return rc; | |
287 | } | |
288 | ||
289 | policy->governor_data = dbs_data; | |
290 | ||
291 | /* policy latency is in nS. Convert it to uS first */ | |
292 | latency = policy->cpuinfo.transition_latency / 1000; | |
293 | if (latency == 0) | |
294 | latency = 1; | |
295 | ||
296 | /* Bring kernel and HW constraints together */ | |
297 | dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate, | |
298 | MIN_LATENCY_MULTIPLIER * latency); | |
299 | set_sampling_rate(dbs_data, max(dbs_data->min_sampling_rate, | |
300 | latency * LATENCY_MULTIPLIER)); | |
301 | ||
a97c98ad VK |
302 | if ((cdata->governor == GOV_CONSERVATIVE) && |
303 | (!policy->governor->initialized)) { | |
4d5dcc42 VK |
304 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; |
305 | ||
306 | cpufreq_register_notifier(cs_ops->notifier_block, | |
307 | CPUFREQ_TRANSITION_NOTIFIER); | |
308 | } | |
309 | ||
310 | if (!have_governor_per_policy()) | |
311 | cdata->gdbs_data = dbs_data; | |
312 | ||
313 | return 0; | |
314 | case CPUFREQ_GOV_POLICY_EXIT: | |
a97c98ad | 315 | if (!--dbs_data->usage_count) { |
4d5dcc42 VK |
316 | sysfs_remove_group(get_governor_parent_kobj(policy), |
317 | get_sysfs_attr(dbs_data)); | |
318 | ||
a97c98ad VK |
319 | if ((dbs_data->cdata->governor == GOV_CONSERVATIVE) && |
320 | (policy->governor->initialized == 1)) { | |
4d5dcc42 VK |
321 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; |
322 | ||
323 | cpufreq_unregister_notifier(cs_ops->notifier_block, | |
324 | CPUFREQ_TRANSITION_NOTIFIER); | |
325 | } | |
326 | ||
327 | cdata->exit(dbs_data); | |
328 | kfree(dbs_data); | |
329 | cdata->gdbs_data = NULL; | |
330 | } | |
4471a34f | 331 | |
4d5dcc42 VK |
332 | policy->governor_data = NULL; |
333 | return 0; | |
334 | } | |
335 | ||
336 | cpu_cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); | |
337 | ||
338 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
339 | cs_tuners = dbs_data->tuners; | |
340 | cs_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
341 | sampling_rate = cs_tuners->sampling_rate; | |
4471a34f VK |
342 | ignore_nice = cs_tuners->ignore_nice; |
343 | } else { | |
4d5dcc42 VK |
344 | od_tuners = dbs_data->tuners; |
345 | od_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
346 | sampling_rate = od_tuners->sampling_rate; | |
4471a34f | 347 | ignore_nice = od_tuners->ignore_nice; |
4d5dcc42 | 348 | od_ops = dbs_data->cdata->gov_ops; |
9366d840 | 349 | io_busy = od_tuners->io_is_busy; |
4471a34f VK |
350 | } |
351 | ||
352 | switch (event) { | |
353 | case CPUFREQ_GOV_START: | |
3361b7b1 | 354 | if (!policy->cur) |
4471a34f VK |
355 | return -EINVAL; |
356 | ||
357 | mutex_lock(&dbs_data->mutex); | |
358 | ||
4471a34f | 359 | for_each_cpu(j, policy->cpus) { |
8eeed095 | 360 | struct cpu_dbs_common_info *j_cdbs = |
4d5dcc42 | 361 | dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f | 362 | |
09dca5ae | 363 | j_cdbs->cpu = j; |
4471a34f VK |
364 | j_cdbs->cur_policy = policy; |
365 | j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, | |
9366d840 | 366 | &j_cdbs->prev_cpu_wall, io_busy); |
4471a34f VK |
367 | if (ignore_nice) |
368 | j_cdbs->prev_cpu_nice = | |
369 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
2abfa876 RA |
370 | |
371 | mutex_init(&j_cdbs->timer_mutex); | |
372 | INIT_DEFERRABLE_WORK(&j_cdbs->work, | |
4d5dcc42 | 373 | dbs_data->cdata->gov_dbs_timer); |
4471a34f VK |
374 | } |
375 | ||
4471a34f VK |
376 | /* |
377 | * conservative does not implement micro like ondemand | |
378 | * governor, thus we are bound to jiffes/HZ | |
379 | */ | |
4d5dcc42 | 380 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { |
8eeed095 VK |
381 | cs_dbs_info->down_skip = 0; |
382 | cs_dbs_info->enable = 1; | |
383 | cs_dbs_info->requested_freq = policy->cur; | |
4471a34f | 384 | } else { |
8eeed095 VK |
385 | od_dbs_info->rate_mult = 1; |
386 | od_dbs_info->sample_type = OD_NORMAL_SAMPLE; | |
387 | od_ops->powersave_bias_init_cpu(cpu); | |
4471a34f VK |
388 | } |
389 | ||
4471a34f VK |
390 | mutex_unlock(&dbs_data->mutex); |
391 | ||
58ddcead FB |
392 | /* Initiate timer time stamp */ |
393 | cpu_cdbs->time_stamp = ktime_get(); | |
da53d61e | 394 | |
031299b3 VK |
395 | gov_queue_work(dbs_data, policy, |
396 | delay_for_sampling_rate(sampling_rate), true); | |
4471a34f VK |
397 | break; |
398 | ||
399 | case CPUFREQ_GOV_STOP: | |
4d5dcc42 | 400 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) |
4471a34f VK |
401 | cs_dbs_info->enable = 0; |
402 | ||
031299b3 | 403 | gov_cancel_work(dbs_data, policy); |
4471a34f VK |
404 | |
405 | mutex_lock(&dbs_data->mutex); | |
406 | mutex_destroy(&cpu_cdbs->timer_mutex); | |
8eeed095 | 407 | |
4471a34f VK |
408 | mutex_unlock(&dbs_data->mutex); |
409 | ||
410 | break; | |
411 | ||
412 | case CPUFREQ_GOV_LIMITS: | |
413 | mutex_lock(&cpu_cdbs->timer_mutex); | |
414 | if (policy->max < cpu_cdbs->cur_policy->cur) | |
415 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
416 | policy->max, CPUFREQ_RELATION_H); | |
417 | else if (policy->min > cpu_cdbs->cur_policy->cur) | |
418 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
419 | policy->min, CPUFREQ_RELATION_L); | |
420 | dbs_check_cpu(dbs_data, cpu); | |
421 | mutex_unlock(&cpu_cdbs->timer_mutex); | |
422 | break; | |
423 | } | |
424 | return 0; | |
425 | } | |
426 | EXPORT_SYMBOL_GPL(cpufreq_governor_dbs); |