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Commit | Line | Data |
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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 VK |
28 | #include <linux/workqueue.h> |
29 | ||
30 | #include "cpufreq_governor.h" | |
31 | ||
4d5dcc42 VK |
32 | static struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
33 | { | |
34 | if (have_governor_per_policy()) | |
35 | return &policy->kobj; | |
36 | else | |
37 | return cpufreq_global_kobject; | |
38 | } | |
39 | ||
40 | static struct attribute_group *get_sysfs_attr(struct dbs_data *dbs_data) | |
41 | { | |
42 | if (have_governor_per_policy()) | |
43 | return dbs_data->cdata->attr_group_gov_pol; | |
44 | else | |
45 | return dbs_data->cdata->attr_group_gov_sys; | |
46 | } | |
47 | ||
2aacdfff | 48 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
49 | { | |
50 | u64 idle_time; | |
51 | u64 cur_wall_time; | |
52 | u64 busy_time; | |
53 | ||
54 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
55 | ||
56 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
57 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
58 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
59 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
60 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
61 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
62 | ||
63 | idle_time = cur_wall_time - busy_time; | |
64 | if (wall) | |
a0e5af3c | 65 | *wall = cputime_to_usecs(cur_wall_time); |
2aacdfff | 66 | |
a0e5af3c | 67 | return cputime_to_usecs(idle_time); |
2aacdfff | 68 | } |
69 | ||
1e7586a1 | 70 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall) |
2aacdfff | 71 | { |
72 | u64 idle_time = get_cpu_idle_time_us(cpu, NULL); | |
73 | ||
74 | if (idle_time == -1ULL) | |
75 | return get_cpu_idle_time_jiffy(cpu, wall); | |
76 | else | |
77 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
78 | ||
79 | return idle_time; | |
80 | } | |
81 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
4471a34f VK |
82 | |
83 | void dbs_check_cpu(struct dbs_data *dbs_data, int cpu) | |
84 | { | |
4d5dcc42 | 85 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f VK |
86 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; |
87 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
88 | struct cpufreq_policy *policy; | |
89 | unsigned int max_load = 0; | |
90 | unsigned int ignore_nice; | |
91 | unsigned int j; | |
92 | ||
4d5dcc42 | 93 | if (dbs_data->cdata->governor == GOV_ONDEMAND) |
4471a34f VK |
94 | ignore_nice = od_tuners->ignore_nice; |
95 | else | |
96 | ignore_nice = cs_tuners->ignore_nice; | |
97 | ||
98 | policy = cdbs->cur_policy; | |
99 | ||
100 | /* Get Absolute Load (in terms of freq for ondemand gov) */ | |
101 | for_each_cpu(j, policy->cpus) { | |
102 | struct cpu_dbs_common_info *j_cdbs; | |
1e7586a1 | 103 | u64 cur_wall_time, cur_idle_time, cur_iowait_time; |
4471a34f VK |
104 | unsigned int idle_time, wall_time, iowait_time; |
105 | unsigned int load; | |
106 | ||
4d5dcc42 | 107 | j_cdbs = dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f VK |
108 | |
109 | cur_idle_time = get_cpu_idle_time(j, &cur_wall_time); | |
110 | ||
111 | wall_time = (unsigned int) | |
112 | (cur_wall_time - j_cdbs->prev_cpu_wall); | |
113 | j_cdbs->prev_cpu_wall = cur_wall_time; | |
114 | ||
115 | idle_time = (unsigned int) | |
116 | (cur_idle_time - j_cdbs->prev_cpu_idle); | |
117 | j_cdbs->prev_cpu_idle = cur_idle_time; | |
118 | ||
119 | if (ignore_nice) { | |
120 | u64 cur_nice; | |
121 | unsigned long cur_nice_jiffies; | |
122 | ||
123 | cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] - | |
124 | cdbs->prev_cpu_nice; | |
125 | /* | |
126 | * Assumption: nice time between sampling periods will | |
127 | * be less than 2^32 jiffies for 32 bit sys | |
128 | */ | |
129 | cur_nice_jiffies = (unsigned long) | |
130 | cputime64_to_jiffies64(cur_nice); | |
131 | ||
132 | cdbs->prev_cpu_nice = | |
133 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
134 | idle_time += jiffies_to_usecs(cur_nice_jiffies); | |
135 | } | |
136 | ||
4d5dcc42 | 137 | if (dbs_data->cdata->governor == GOV_ONDEMAND) { |
4471a34f | 138 | struct od_cpu_dbs_info_s *od_j_dbs_info = |
4d5dcc42 | 139 | dbs_data->cdata->get_cpu_dbs_info_s(cpu); |
4471a34f VK |
140 | |
141 | cur_iowait_time = get_cpu_iowait_time_us(j, | |
142 | &cur_wall_time); | |
143 | if (cur_iowait_time == -1ULL) | |
144 | cur_iowait_time = 0; | |
145 | ||
146 | iowait_time = (unsigned int) (cur_iowait_time - | |
147 | od_j_dbs_info->prev_cpu_iowait); | |
148 | od_j_dbs_info->prev_cpu_iowait = cur_iowait_time; | |
149 | ||
150 | /* | |
151 | * For the purpose of ondemand, waiting for disk IO is | |
152 | * an indication that you're performance critical, and | |
153 | * not that the system is actually idle. So subtract the | |
154 | * iowait time from the cpu idle time. | |
155 | */ | |
156 | if (od_tuners->io_is_busy && idle_time >= iowait_time) | |
157 | idle_time -= iowait_time; | |
158 | } | |
159 | ||
160 | if (unlikely(!wall_time || wall_time < idle_time)) | |
161 | continue; | |
162 | ||
163 | load = 100 * (wall_time - idle_time) / wall_time; | |
164 | ||
4d5dcc42 | 165 | if (dbs_data->cdata->governor == GOV_ONDEMAND) { |
4471a34f VK |
166 | int freq_avg = __cpufreq_driver_getavg(policy, j); |
167 | if (freq_avg <= 0) | |
168 | freq_avg = policy->cur; | |
169 | ||
170 | load *= freq_avg; | |
171 | } | |
172 | ||
173 | if (load > max_load) | |
174 | max_load = load; | |
175 | } | |
176 | ||
4d5dcc42 | 177 | dbs_data->cdata->gov_check_cpu(cpu, max_load); |
4471a34f VK |
178 | } |
179 | EXPORT_SYMBOL_GPL(dbs_check_cpu); | |
180 | ||
031299b3 VK |
181 | static inline void __gov_queue_work(int cpu, struct dbs_data *dbs_data, |
182 | unsigned int delay) | |
4471a34f | 183 | { |
4d5dcc42 | 184 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f | 185 | |
031299b3 | 186 | mod_delayed_work_on(cpu, system_wq, &cdbs->work, delay); |
4471a34f VK |
187 | } |
188 | ||
031299b3 VK |
189 | void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, |
190 | unsigned int delay, bool all_cpus) | |
4471a34f | 191 | { |
031299b3 VK |
192 | int i; |
193 | ||
194 | if (!all_cpus) { | |
195 | __gov_queue_work(smp_processor_id(), dbs_data, delay); | |
196 | } else { | |
197 | for_each_cpu(i, policy->cpus) | |
198 | __gov_queue_work(i, dbs_data, delay); | |
199 | } | |
200 | } | |
201 | EXPORT_SYMBOL_GPL(gov_queue_work); | |
202 | ||
203 | static inline void gov_cancel_work(struct dbs_data *dbs_data, | |
204 | struct cpufreq_policy *policy) | |
205 | { | |
206 | struct cpu_dbs_common_info *cdbs; | |
207 | int i; | |
58ddcead | 208 | |
031299b3 VK |
209 | for_each_cpu(i, policy->cpus) { |
210 | cdbs = dbs_data->cdata->get_cpu_cdbs(i); | |
211 | cancel_delayed_work_sync(&cdbs->work); | |
212 | } | |
4471a34f VK |
213 | } |
214 | ||
4447266b VK |
215 | /* Will return if we need to evaluate cpu load again or not */ |
216 | bool need_load_eval(struct cpu_dbs_common_info *cdbs, | |
217 | unsigned int sampling_rate) | |
218 | { | |
219 | if (policy_is_shared(cdbs->cur_policy)) { | |
220 | ktime_t time_now = ktime_get(); | |
221 | s64 delta_us = ktime_us_delta(time_now, cdbs->time_stamp); | |
222 | ||
223 | /* Do nothing if we recently have sampled */ | |
224 | if (delta_us < (s64)(sampling_rate / 2)) | |
225 | return false; | |
226 | else | |
227 | cdbs->time_stamp = time_now; | |
228 | } | |
229 | ||
230 | return true; | |
231 | } | |
232 | EXPORT_SYMBOL_GPL(need_load_eval); | |
233 | ||
4d5dcc42 VK |
234 | static void set_sampling_rate(struct dbs_data *dbs_data, |
235 | unsigned int sampling_rate) | |
236 | { | |
237 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
238 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
239 | cs_tuners->sampling_rate = sampling_rate; | |
240 | } else { | |
241 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; | |
242 | od_tuners->sampling_rate = sampling_rate; | |
243 | } | |
244 | } | |
245 | ||
246 | int cpufreq_governor_dbs(struct cpufreq_policy *policy, | |
247 | struct common_dbs_data *cdata, unsigned int event) | |
4471a34f | 248 | { |
4d5dcc42 | 249 | struct dbs_data *dbs_data; |
4471a34f VK |
250 | struct od_cpu_dbs_info_s *od_dbs_info = NULL; |
251 | struct cs_cpu_dbs_info_s *cs_dbs_info = NULL; | |
8eeed095 | 252 | struct od_ops *od_ops = NULL; |
4d5dcc42 VK |
253 | struct od_dbs_tuners *od_tuners = NULL; |
254 | struct cs_dbs_tuners *cs_tuners = NULL; | |
4471a34f | 255 | struct cpu_dbs_common_info *cpu_cdbs; |
4d5dcc42 | 256 | unsigned int sampling_rate, latency, ignore_nice, j, cpu = policy->cpu; |
4471a34f VK |
257 | int rc; |
258 | ||
4d5dcc42 VK |
259 | if (have_governor_per_policy()) |
260 | dbs_data = policy->governor_data; | |
261 | else | |
262 | dbs_data = cdata->gdbs_data; | |
263 | ||
264 | WARN_ON(!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT)); | |
265 | ||
266 | switch (event) { | |
267 | case CPUFREQ_GOV_POLICY_INIT: | |
268 | if (have_governor_per_policy()) { | |
269 | WARN_ON(dbs_data); | |
270 | } else if (dbs_data) { | |
271 | policy->governor_data = dbs_data; | |
272 | return 0; | |
273 | } | |
274 | ||
275 | dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL); | |
276 | if (!dbs_data) { | |
277 | pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__); | |
278 | return -ENOMEM; | |
279 | } | |
280 | ||
281 | dbs_data->cdata = cdata; | |
282 | rc = cdata->init(dbs_data); | |
283 | if (rc) { | |
284 | pr_err("%s: POLICY_INIT: init() failed\n", __func__); | |
285 | kfree(dbs_data); | |
286 | return rc; | |
287 | } | |
288 | ||
289 | rc = sysfs_create_group(get_governor_parent_kobj(policy), | |
290 | get_sysfs_attr(dbs_data)); | |
291 | if (rc) { | |
292 | cdata->exit(dbs_data); | |
293 | kfree(dbs_data); | |
294 | return rc; | |
295 | } | |
296 | ||
297 | policy->governor_data = dbs_data; | |
298 | ||
299 | /* policy latency is in nS. Convert it to uS first */ | |
300 | latency = policy->cpuinfo.transition_latency / 1000; | |
301 | if (latency == 0) | |
302 | latency = 1; | |
303 | ||
304 | /* Bring kernel and HW constraints together */ | |
305 | dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate, | |
306 | MIN_LATENCY_MULTIPLIER * latency); | |
307 | set_sampling_rate(dbs_data, max(dbs_data->min_sampling_rate, | |
308 | latency * LATENCY_MULTIPLIER)); | |
309 | ||
310 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
311 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; | |
312 | ||
313 | cpufreq_register_notifier(cs_ops->notifier_block, | |
314 | CPUFREQ_TRANSITION_NOTIFIER); | |
315 | } | |
316 | ||
317 | if (!have_governor_per_policy()) | |
318 | cdata->gdbs_data = dbs_data; | |
319 | ||
320 | return 0; | |
321 | case CPUFREQ_GOV_POLICY_EXIT: | |
322 | if ((policy->governor->initialized == 1) || | |
323 | have_governor_per_policy()) { | |
324 | sysfs_remove_group(get_governor_parent_kobj(policy), | |
325 | get_sysfs_attr(dbs_data)); | |
326 | ||
327 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
328 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; | |
329 | ||
330 | cpufreq_unregister_notifier(cs_ops->notifier_block, | |
331 | CPUFREQ_TRANSITION_NOTIFIER); | |
332 | } | |
333 | ||
334 | cdata->exit(dbs_data); | |
335 | kfree(dbs_data); | |
336 | cdata->gdbs_data = NULL; | |
337 | } | |
4471a34f | 338 | |
4d5dcc42 VK |
339 | policy->governor_data = NULL; |
340 | return 0; | |
341 | } | |
342 | ||
343 | cpu_cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); | |
344 | ||
345 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
346 | cs_tuners = dbs_data->tuners; | |
347 | cs_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
348 | sampling_rate = cs_tuners->sampling_rate; | |
4471a34f VK |
349 | ignore_nice = cs_tuners->ignore_nice; |
350 | } else { | |
4d5dcc42 VK |
351 | od_tuners = dbs_data->tuners; |
352 | od_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
353 | sampling_rate = od_tuners->sampling_rate; | |
4471a34f | 354 | ignore_nice = od_tuners->ignore_nice; |
4d5dcc42 | 355 | od_ops = dbs_data->cdata->gov_ops; |
4471a34f VK |
356 | } |
357 | ||
358 | switch (event) { | |
359 | case CPUFREQ_GOV_START: | |
3361b7b1 | 360 | if (!policy->cur) |
4471a34f VK |
361 | return -EINVAL; |
362 | ||
363 | mutex_lock(&dbs_data->mutex); | |
364 | ||
4471a34f | 365 | for_each_cpu(j, policy->cpus) { |
8eeed095 | 366 | struct cpu_dbs_common_info *j_cdbs = |
4d5dcc42 | 367 | dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f | 368 | |
09dca5ae | 369 | j_cdbs->cpu = j; |
4471a34f VK |
370 | j_cdbs->cur_policy = policy; |
371 | j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, | |
372 | &j_cdbs->prev_cpu_wall); | |
373 | if (ignore_nice) | |
374 | j_cdbs->prev_cpu_nice = | |
375 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
2abfa876 RA |
376 | |
377 | mutex_init(&j_cdbs->timer_mutex); | |
378 | INIT_DEFERRABLE_WORK(&j_cdbs->work, | |
4d5dcc42 | 379 | dbs_data->cdata->gov_dbs_timer); |
4471a34f VK |
380 | } |
381 | ||
4471a34f VK |
382 | /* |
383 | * conservative does not implement micro like ondemand | |
384 | * governor, thus we are bound to jiffes/HZ | |
385 | */ | |
4d5dcc42 | 386 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { |
8eeed095 VK |
387 | cs_dbs_info->down_skip = 0; |
388 | cs_dbs_info->enable = 1; | |
389 | cs_dbs_info->requested_freq = policy->cur; | |
4471a34f | 390 | } else { |
8eeed095 VK |
391 | od_dbs_info->rate_mult = 1; |
392 | od_dbs_info->sample_type = OD_NORMAL_SAMPLE; | |
393 | od_ops->powersave_bias_init_cpu(cpu); | |
4471a34f VK |
394 | } |
395 | ||
4471a34f VK |
396 | mutex_unlock(&dbs_data->mutex); |
397 | ||
58ddcead FB |
398 | /* Initiate timer time stamp */ |
399 | cpu_cdbs->time_stamp = ktime_get(); | |
da53d61e | 400 | |
031299b3 VK |
401 | gov_queue_work(dbs_data, policy, |
402 | delay_for_sampling_rate(sampling_rate), true); | |
4471a34f VK |
403 | break; |
404 | ||
405 | case CPUFREQ_GOV_STOP: | |
4d5dcc42 | 406 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) |
4471a34f VK |
407 | cs_dbs_info->enable = 0; |
408 | ||
031299b3 | 409 | gov_cancel_work(dbs_data, policy); |
4471a34f VK |
410 | |
411 | mutex_lock(&dbs_data->mutex); | |
412 | mutex_destroy(&cpu_cdbs->timer_mutex); | |
8eeed095 | 413 | |
4471a34f VK |
414 | mutex_unlock(&dbs_data->mutex); |
415 | ||
416 | break; | |
417 | ||
418 | case CPUFREQ_GOV_LIMITS: | |
419 | mutex_lock(&cpu_cdbs->timer_mutex); | |
420 | if (policy->max < cpu_cdbs->cur_policy->cur) | |
421 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
422 | policy->max, CPUFREQ_RELATION_H); | |
423 | else if (policy->min > cpu_cdbs->cur_policy->cur) | |
424 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
425 | policy->min, CPUFREQ_RELATION_L); | |
426 | dbs_check_cpu(dbs_data, cpu); | |
427 | mutex_unlock(&cpu_cdbs->timer_mutex); | |
428 | break; | |
429 | } | |
430 | return 0; | |
431 | } | |
432 | EXPORT_SYMBOL_GPL(cpufreq_governor_dbs); |