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/types.h> |
4471a34f VK |
27 | #include <linux/workqueue.h> |
28 | ||
29 | #include "cpufreq_governor.h" | |
30 | ||
4d5dcc42 VK |
31 | static struct attribute_group *get_sysfs_attr(struct dbs_data *dbs_data) |
32 | { | |
33 | if (have_governor_per_policy()) | |
34 | return dbs_data->cdata->attr_group_gov_pol; | |
35 | else | |
36 | return dbs_data->cdata->attr_group_gov_sys; | |
37 | } | |
38 | ||
4471a34f VK |
39 | void dbs_check_cpu(struct dbs_data *dbs_data, int cpu) |
40 | { | |
4d5dcc42 | 41 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f VK |
42 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; |
43 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
44 | struct cpufreq_policy *policy; | |
45 | unsigned int max_load = 0; | |
46 | unsigned int ignore_nice; | |
47 | unsigned int j; | |
48 | ||
4d5dcc42 | 49 | if (dbs_data->cdata->governor == GOV_ONDEMAND) |
4471a34f VK |
50 | ignore_nice = od_tuners->ignore_nice; |
51 | else | |
52 | ignore_nice = cs_tuners->ignore_nice; | |
53 | ||
54 | policy = cdbs->cur_policy; | |
55 | ||
56 | /* Get Absolute Load (in terms of freq for ondemand gov) */ | |
57 | for_each_cpu(j, policy->cpus) { | |
58 | struct cpu_dbs_common_info *j_cdbs; | |
9366d840 SK |
59 | u64 cur_wall_time, cur_idle_time; |
60 | unsigned int idle_time, wall_time; | |
4471a34f | 61 | unsigned int load; |
9366d840 | 62 | int io_busy = 0; |
4471a34f | 63 | |
4d5dcc42 | 64 | j_cdbs = dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f | 65 | |
9366d840 SK |
66 | /* |
67 | * For the purpose of ondemand, waiting for disk IO is | |
68 | * an indication that you're performance critical, and | |
69 | * not that the system is actually idle. So do not add | |
70 | * the iowait time to the cpu idle time. | |
71 | */ | |
72 | if (dbs_data->cdata->governor == GOV_ONDEMAND) | |
73 | io_busy = od_tuners->io_is_busy; | |
74 | cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy); | |
4471a34f VK |
75 | |
76 | wall_time = (unsigned int) | |
77 | (cur_wall_time - j_cdbs->prev_cpu_wall); | |
78 | j_cdbs->prev_cpu_wall = cur_wall_time; | |
79 | ||
80 | idle_time = (unsigned int) | |
81 | (cur_idle_time - j_cdbs->prev_cpu_idle); | |
82 | j_cdbs->prev_cpu_idle = cur_idle_time; | |
83 | ||
84 | if (ignore_nice) { | |
85 | u64 cur_nice; | |
86 | unsigned long cur_nice_jiffies; | |
87 | ||
88 | cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] - | |
89 | cdbs->prev_cpu_nice; | |
90 | /* | |
91 | * Assumption: nice time between sampling periods will | |
92 | * be less than 2^32 jiffies for 32 bit sys | |
93 | */ | |
94 | cur_nice_jiffies = (unsigned long) | |
95 | cputime64_to_jiffies64(cur_nice); | |
96 | ||
97 | cdbs->prev_cpu_nice = | |
98 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
99 | idle_time += jiffies_to_usecs(cur_nice_jiffies); | |
100 | } | |
101 | ||
4471a34f VK |
102 | if (unlikely(!wall_time || wall_time < idle_time)) |
103 | continue; | |
104 | ||
105 | load = 100 * (wall_time - idle_time) / wall_time; | |
106 | ||
4d5dcc42 | 107 | if (dbs_data->cdata->governor == GOV_ONDEMAND) { |
4471a34f VK |
108 | int freq_avg = __cpufreq_driver_getavg(policy, j); |
109 | if (freq_avg <= 0) | |
110 | freq_avg = policy->cur; | |
111 | ||
112 | load *= freq_avg; | |
113 | } | |
114 | ||
115 | if (load > max_load) | |
116 | max_load = load; | |
117 | } | |
118 | ||
4d5dcc42 | 119 | dbs_data->cdata->gov_check_cpu(cpu, max_load); |
4471a34f VK |
120 | } |
121 | EXPORT_SYMBOL_GPL(dbs_check_cpu); | |
122 | ||
031299b3 VK |
123 | static inline void __gov_queue_work(int cpu, struct dbs_data *dbs_data, |
124 | unsigned int delay) | |
4471a34f | 125 | { |
4d5dcc42 | 126 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f | 127 | |
031299b3 | 128 | mod_delayed_work_on(cpu, system_wq, &cdbs->work, delay); |
4471a34f VK |
129 | } |
130 | ||
031299b3 VK |
131 | void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, |
132 | unsigned int delay, bool all_cpus) | |
4471a34f | 133 | { |
031299b3 VK |
134 | int i; |
135 | ||
136 | if (!all_cpus) { | |
137 | __gov_queue_work(smp_processor_id(), dbs_data, delay); | |
138 | } else { | |
139 | for_each_cpu(i, policy->cpus) | |
140 | __gov_queue_work(i, dbs_data, delay); | |
141 | } | |
142 | } | |
143 | EXPORT_SYMBOL_GPL(gov_queue_work); | |
144 | ||
145 | static inline void gov_cancel_work(struct dbs_data *dbs_data, | |
146 | struct cpufreq_policy *policy) | |
147 | { | |
148 | struct cpu_dbs_common_info *cdbs; | |
149 | int i; | |
58ddcead | 150 | |
031299b3 VK |
151 | for_each_cpu(i, policy->cpus) { |
152 | cdbs = dbs_data->cdata->get_cpu_cdbs(i); | |
153 | cancel_delayed_work_sync(&cdbs->work); | |
154 | } | |
4471a34f VK |
155 | } |
156 | ||
4447266b VK |
157 | /* Will return if we need to evaluate cpu load again or not */ |
158 | bool need_load_eval(struct cpu_dbs_common_info *cdbs, | |
159 | unsigned int sampling_rate) | |
160 | { | |
161 | if (policy_is_shared(cdbs->cur_policy)) { | |
162 | ktime_t time_now = ktime_get(); | |
163 | s64 delta_us = ktime_us_delta(time_now, cdbs->time_stamp); | |
164 | ||
165 | /* Do nothing if we recently have sampled */ | |
166 | if (delta_us < (s64)(sampling_rate / 2)) | |
167 | return false; | |
168 | else | |
169 | cdbs->time_stamp = time_now; | |
170 | } | |
171 | ||
172 | return true; | |
173 | } | |
174 | EXPORT_SYMBOL_GPL(need_load_eval); | |
175 | ||
4d5dcc42 VK |
176 | static void set_sampling_rate(struct dbs_data *dbs_data, |
177 | unsigned int sampling_rate) | |
178 | { | |
179 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
180 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
181 | cs_tuners->sampling_rate = sampling_rate; | |
182 | } else { | |
183 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; | |
184 | od_tuners->sampling_rate = sampling_rate; | |
185 | } | |
186 | } | |
187 | ||
188 | int cpufreq_governor_dbs(struct cpufreq_policy *policy, | |
189 | struct common_dbs_data *cdata, unsigned int event) | |
4471a34f | 190 | { |
4d5dcc42 | 191 | struct dbs_data *dbs_data; |
4471a34f VK |
192 | struct od_cpu_dbs_info_s *od_dbs_info = NULL; |
193 | struct cs_cpu_dbs_info_s *cs_dbs_info = NULL; | |
8eeed095 | 194 | struct od_ops *od_ops = NULL; |
4d5dcc42 VK |
195 | struct od_dbs_tuners *od_tuners = NULL; |
196 | struct cs_dbs_tuners *cs_tuners = NULL; | |
4471a34f | 197 | struct cpu_dbs_common_info *cpu_cdbs; |
4d5dcc42 | 198 | unsigned int sampling_rate, latency, ignore_nice, j, cpu = policy->cpu; |
9366d840 | 199 | int io_busy = 0; |
4471a34f VK |
200 | int rc; |
201 | ||
4d5dcc42 VK |
202 | if (have_governor_per_policy()) |
203 | dbs_data = policy->governor_data; | |
204 | else | |
205 | dbs_data = cdata->gdbs_data; | |
206 | ||
207 | WARN_ON(!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT)); | |
208 | ||
209 | switch (event) { | |
210 | case CPUFREQ_GOV_POLICY_INIT: | |
211 | if (have_governor_per_policy()) { | |
212 | WARN_ON(dbs_data); | |
213 | } else if (dbs_data) { | |
a97c98ad | 214 | dbs_data->usage_count++; |
4d5dcc42 VK |
215 | policy->governor_data = dbs_data; |
216 | return 0; | |
217 | } | |
218 | ||
219 | dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL); | |
220 | if (!dbs_data) { | |
221 | pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__); | |
222 | return -ENOMEM; | |
223 | } | |
224 | ||
225 | dbs_data->cdata = cdata; | |
a97c98ad | 226 | dbs_data->usage_count = 1; |
4d5dcc42 VK |
227 | rc = cdata->init(dbs_data); |
228 | if (rc) { | |
229 | pr_err("%s: POLICY_INIT: init() failed\n", __func__); | |
230 | kfree(dbs_data); | |
231 | return rc; | |
232 | } | |
233 | ||
2361be23 VK |
234 | if (!have_governor_per_policy()) |
235 | WARN_ON(cpufreq_get_global_kobject()); | |
236 | ||
4d5dcc42 VK |
237 | rc = sysfs_create_group(get_governor_parent_kobj(policy), |
238 | get_sysfs_attr(dbs_data)); | |
239 | if (rc) { | |
240 | cdata->exit(dbs_data); | |
241 | kfree(dbs_data); | |
242 | return rc; | |
243 | } | |
244 | ||
245 | policy->governor_data = dbs_data; | |
246 | ||
247 | /* policy latency is in nS. Convert it to uS first */ | |
248 | latency = policy->cpuinfo.transition_latency / 1000; | |
249 | if (latency == 0) | |
250 | latency = 1; | |
251 | ||
252 | /* Bring kernel and HW constraints together */ | |
253 | dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate, | |
254 | MIN_LATENCY_MULTIPLIER * latency); | |
255 | set_sampling_rate(dbs_data, max(dbs_data->min_sampling_rate, | |
256 | latency * LATENCY_MULTIPLIER)); | |
257 | ||
a97c98ad VK |
258 | if ((cdata->governor == GOV_CONSERVATIVE) && |
259 | (!policy->governor->initialized)) { | |
4d5dcc42 VK |
260 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; |
261 | ||
262 | cpufreq_register_notifier(cs_ops->notifier_block, | |
263 | CPUFREQ_TRANSITION_NOTIFIER); | |
264 | } | |
265 | ||
266 | if (!have_governor_per_policy()) | |
267 | cdata->gdbs_data = dbs_data; | |
268 | ||
269 | return 0; | |
270 | case CPUFREQ_GOV_POLICY_EXIT: | |
a97c98ad | 271 | if (!--dbs_data->usage_count) { |
4d5dcc42 VK |
272 | sysfs_remove_group(get_governor_parent_kobj(policy), |
273 | get_sysfs_attr(dbs_data)); | |
274 | ||
2361be23 VK |
275 | if (!have_governor_per_policy()) |
276 | cpufreq_put_global_kobject(); | |
277 | ||
a97c98ad VK |
278 | if ((dbs_data->cdata->governor == GOV_CONSERVATIVE) && |
279 | (policy->governor->initialized == 1)) { | |
4d5dcc42 VK |
280 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; |
281 | ||
282 | cpufreq_unregister_notifier(cs_ops->notifier_block, | |
283 | CPUFREQ_TRANSITION_NOTIFIER); | |
284 | } | |
285 | ||
286 | cdata->exit(dbs_data); | |
287 | kfree(dbs_data); | |
288 | cdata->gdbs_data = NULL; | |
289 | } | |
4471a34f | 290 | |
4d5dcc42 VK |
291 | policy->governor_data = NULL; |
292 | return 0; | |
293 | } | |
294 | ||
295 | cpu_cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); | |
296 | ||
297 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
298 | cs_tuners = dbs_data->tuners; | |
299 | cs_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
300 | sampling_rate = cs_tuners->sampling_rate; | |
4471a34f VK |
301 | ignore_nice = cs_tuners->ignore_nice; |
302 | } else { | |
4d5dcc42 VK |
303 | od_tuners = dbs_data->tuners; |
304 | od_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
305 | sampling_rate = od_tuners->sampling_rate; | |
4471a34f | 306 | ignore_nice = od_tuners->ignore_nice; |
4d5dcc42 | 307 | od_ops = dbs_data->cdata->gov_ops; |
9366d840 | 308 | io_busy = od_tuners->io_is_busy; |
4471a34f VK |
309 | } |
310 | ||
311 | switch (event) { | |
312 | case CPUFREQ_GOV_START: | |
3361b7b1 | 313 | if (!policy->cur) |
4471a34f VK |
314 | return -EINVAL; |
315 | ||
316 | mutex_lock(&dbs_data->mutex); | |
317 | ||
4471a34f | 318 | for_each_cpu(j, policy->cpus) { |
8eeed095 | 319 | struct cpu_dbs_common_info *j_cdbs = |
4d5dcc42 | 320 | dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f | 321 | |
09dca5ae | 322 | j_cdbs->cpu = j; |
4471a34f VK |
323 | j_cdbs->cur_policy = policy; |
324 | j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, | |
9366d840 | 325 | &j_cdbs->prev_cpu_wall, io_busy); |
4471a34f VK |
326 | if (ignore_nice) |
327 | j_cdbs->prev_cpu_nice = | |
328 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
2abfa876 RA |
329 | |
330 | mutex_init(&j_cdbs->timer_mutex); | |
331 | INIT_DEFERRABLE_WORK(&j_cdbs->work, | |
4d5dcc42 | 332 | dbs_data->cdata->gov_dbs_timer); |
4471a34f VK |
333 | } |
334 | ||
4471a34f VK |
335 | /* |
336 | * conservative does not implement micro like ondemand | |
337 | * governor, thus we are bound to jiffes/HZ | |
338 | */ | |
4d5dcc42 | 339 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { |
8eeed095 VK |
340 | cs_dbs_info->down_skip = 0; |
341 | cs_dbs_info->enable = 1; | |
342 | cs_dbs_info->requested_freq = policy->cur; | |
4471a34f | 343 | } else { |
8eeed095 VK |
344 | od_dbs_info->rate_mult = 1; |
345 | od_dbs_info->sample_type = OD_NORMAL_SAMPLE; | |
346 | od_ops->powersave_bias_init_cpu(cpu); | |
4471a34f VK |
347 | } |
348 | ||
4471a34f VK |
349 | mutex_unlock(&dbs_data->mutex); |
350 | ||
58ddcead FB |
351 | /* Initiate timer time stamp */ |
352 | cpu_cdbs->time_stamp = ktime_get(); | |
da53d61e | 353 | |
031299b3 VK |
354 | gov_queue_work(dbs_data, policy, |
355 | delay_for_sampling_rate(sampling_rate), true); | |
4471a34f VK |
356 | break; |
357 | ||
358 | case CPUFREQ_GOV_STOP: | |
4d5dcc42 | 359 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) |
4471a34f VK |
360 | cs_dbs_info->enable = 0; |
361 | ||
031299b3 | 362 | gov_cancel_work(dbs_data, policy); |
4471a34f VK |
363 | |
364 | mutex_lock(&dbs_data->mutex); | |
365 | mutex_destroy(&cpu_cdbs->timer_mutex); | |
419e1721 | 366 | cpu_cdbs->cur_policy = NULL; |
8eeed095 | 367 | |
4471a34f VK |
368 | mutex_unlock(&dbs_data->mutex); |
369 | ||
370 | break; | |
371 | ||
372 | case CPUFREQ_GOV_LIMITS: | |
373 | mutex_lock(&cpu_cdbs->timer_mutex); | |
374 | if (policy->max < cpu_cdbs->cur_policy->cur) | |
375 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
376 | policy->max, CPUFREQ_RELATION_H); | |
377 | else if (policy->min > cpu_cdbs->cur_policy->cur) | |
378 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
379 | policy->min, CPUFREQ_RELATION_L); | |
380 | dbs_check_cpu(dbs_data, cpu); | |
381 | mutex_unlock(&cpu_cdbs->timer_mutex); | |
382 | break; | |
383 | } | |
384 | return 0; | |
385 | } | |
386 | EXPORT_SYMBOL_GPL(cpufreq_governor_dbs); |