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 <linux/export.h> |
20 | #include <linux/kernel_stat.h> | |
4d5dcc42 | 21 | #include <linux/slab.h> |
4471a34f VK |
22 | |
23 | #include "cpufreq_governor.h" | |
24 | ||
4d5dcc42 VK |
25 | static struct attribute_group *get_sysfs_attr(struct dbs_data *dbs_data) |
26 | { | |
27 | if (have_governor_per_policy()) | |
28 | return dbs_data->cdata->attr_group_gov_pol; | |
29 | else | |
30 | return dbs_data->cdata->attr_group_gov_sys; | |
31 | } | |
32 | ||
4471a34f VK |
33 | void dbs_check_cpu(struct dbs_data *dbs_data, int cpu) |
34 | { | |
4d5dcc42 | 35 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f VK |
36 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; |
37 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
38 | struct cpufreq_policy *policy; | |
39 | unsigned int max_load = 0; | |
40 | unsigned int ignore_nice; | |
41 | unsigned int j; | |
42 | ||
4d5dcc42 | 43 | if (dbs_data->cdata->governor == GOV_ONDEMAND) |
6c4640c3 | 44 | ignore_nice = od_tuners->ignore_nice_load; |
4471a34f | 45 | else |
6c4640c3 | 46 | ignore_nice = cs_tuners->ignore_nice_load; |
4471a34f VK |
47 | |
48 | policy = cdbs->cur_policy; | |
49 | ||
dfa5bb62 | 50 | /* Get Absolute Load */ |
4471a34f VK |
51 | for_each_cpu(j, policy->cpus) { |
52 | struct cpu_dbs_common_info *j_cdbs; | |
9366d840 SK |
53 | u64 cur_wall_time, cur_idle_time; |
54 | unsigned int idle_time, wall_time; | |
4471a34f | 55 | unsigned int load; |
9366d840 | 56 | int io_busy = 0; |
4471a34f | 57 | |
4d5dcc42 | 58 | j_cdbs = dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f | 59 | |
9366d840 SK |
60 | /* |
61 | * For the purpose of ondemand, waiting for disk IO is | |
62 | * an indication that you're performance critical, and | |
63 | * not that the system is actually idle. So do not add | |
64 | * the iowait time to the cpu idle time. | |
65 | */ | |
66 | if (dbs_data->cdata->governor == GOV_ONDEMAND) | |
67 | io_busy = od_tuners->io_is_busy; | |
68 | cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy); | |
4471a34f VK |
69 | |
70 | wall_time = (unsigned int) | |
71 | (cur_wall_time - j_cdbs->prev_cpu_wall); | |
72 | j_cdbs->prev_cpu_wall = cur_wall_time; | |
73 | ||
74 | idle_time = (unsigned int) | |
75 | (cur_idle_time - j_cdbs->prev_cpu_idle); | |
76 | j_cdbs->prev_cpu_idle = cur_idle_time; | |
77 | ||
78 | if (ignore_nice) { | |
79 | u64 cur_nice; | |
80 | unsigned long cur_nice_jiffies; | |
81 | ||
82 | cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] - | |
83 | cdbs->prev_cpu_nice; | |
84 | /* | |
85 | * Assumption: nice time between sampling periods will | |
86 | * be less than 2^32 jiffies for 32 bit sys | |
87 | */ | |
88 | cur_nice_jiffies = (unsigned long) | |
89 | cputime64_to_jiffies64(cur_nice); | |
90 | ||
91 | cdbs->prev_cpu_nice = | |
92 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
93 | idle_time += jiffies_to_usecs(cur_nice_jiffies); | |
94 | } | |
95 | ||
4471a34f VK |
96 | if (unlikely(!wall_time || wall_time < idle_time)) |
97 | continue; | |
98 | ||
99 | load = 100 * (wall_time - idle_time) / wall_time; | |
100 | ||
4471a34f VK |
101 | if (load > max_load) |
102 | max_load = load; | |
103 | } | |
104 | ||
4d5dcc42 | 105 | dbs_data->cdata->gov_check_cpu(cpu, max_load); |
4471a34f VK |
106 | } |
107 | EXPORT_SYMBOL_GPL(dbs_check_cpu); | |
108 | ||
031299b3 VK |
109 | static inline void __gov_queue_work(int cpu, struct dbs_data *dbs_data, |
110 | unsigned int delay) | |
4471a34f | 111 | { |
4d5dcc42 | 112 | struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); |
4471a34f | 113 | |
031299b3 | 114 | mod_delayed_work_on(cpu, system_wq, &cdbs->work, delay); |
4471a34f VK |
115 | } |
116 | ||
031299b3 VK |
117 | void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, |
118 | unsigned int delay, bool all_cpus) | |
4471a34f | 119 | { |
031299b3 VK |
120 | int i; |
121 | ||
3617f2ca SB |
122 | if (!policy->governor_enabled) |
123 | return; | |
124 | ||
031299b3 | 125 | if (!all_cpus) { |
69320783 SB |
126 | /* |
127 | * Use raw_smp_processor_id() to avoid preemptible warnings. | |
128 | * We know that this is only called with all_cpus == false from | |
129 | * works that have been queued with *_work_on() functions and | |
130 | * those works are canceled during CPU_DOWN_PREPARE so they | |
131 | * can't possibly run on any other CPU. | |
132 | */ | |
133 | __gov_queue_work(raw_smp_processor_id(), dbs_data, delay); | |
031299b3 VK |
134 | } else { |
135 | for_each_cpu(i, policy->cpus) | |
136 | __gov_queue_work(i, dbs_data, delay); | |
137 | } | |
138 | } | |
139 | EXPORT_SYMBOL_GPL(gov_queue_work); | |
140 | ||
141 | static inline void gov_cancel_work(struct dbs_data *dbs_data, | |
142 | struct cpufreq_policy *policy) | |
143 | { | |
144 | struct cpu_dbs_common_info *cdbs; | |
145 | int i; | |
58ddcead | 146 | |
031299b3 VK |
147 | for_each_cpu(i, policy->cpus) { |
148 | cdbs = dbs_data->cdata->get_cpu_cdbs(i); | |
149 | cancel_delayed_work_sync(&cdbs->work); | |
150 | } | |
4471a34f VK |
151 | } |
152 | ||
4447266b VK |
153 | /* Will return if we need to evaluate cpu load again or not */ |
154 | bool need_load_eval(struct cpu_dbs_common_info *cdbs, | |
155 | unsigned int sampling_rate) | |
156 | { | |
157 | if (policy_is_shared(cdbs->cur_policy)) { | |
158 | ktime_t time_now = ktime_get(); | |
159 | s64 delta_us = ktime_us_delta(time_now, cdbs->time_stamp); | |
160 | ||
161 | /* Do nothing if we recently have sampled */ | |
162 | if (delta_us < (s64)(sampling_rate / 2)) | |
163 | return false; | |
164 | else | |
165 | cdbs->time_stamp = time_now; | |
166 | } | |
167 | ||
168 | return true; | |
169 | } | |
170 | EXPORT_SYMBOL_GPL(need_load_eval); | |
171 | ||
4d5dcc42 VK |
172 | static void set_sampling_rate(struct dbs_data *dbs_data, |
173 | unsigned int sampling_rate) | |
174 | { | |
175 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
176 | struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; | |
177 | cs_tuners->sampling_rate = sampling_rate; | |
178 | } else { | |
179 | struct od_dbs_tuners *od_tuners = dbs_data->tuners; | |
180 | od_tuners->sampling_rate = sampling_rate; | |
181 | } | |
182 | } | |
183 | ||
184 | int cpufreq_governor_dbs(struct cpufreq_policy *policy, | |
185 | struct common_dbs_data *cdata, unsigned int event) | |
4471a34f | 186 | { |
4d5dcc42 | 187 | struct dbs_data *dbs_data; |
4471a34f VK |
188 | struct od_cpu_dbs_info_s *od_dbs_info = NULL; |
189 | struct cs_cpu_dbs_info_s *cs_dbs_info = NULL; | |
8eeed095 | 190 | struct od_ops *od_ops = NULL; |
4d5dcc42 VK |
191 | struct od_dbs_tuners *od_tuners = NULL; |
192 | struct cs_dbs_tuners *cs_tuners = NULL; | |
4471a34f | 193 | struct cpu_dbs_common_info *cpu_cdbs; |
4d5dcc42 | 194 | unsigned int sampling_rate, latency, ignore_nice, j, cpu = policy->cpu; |
9366d840 | 195 | int io_busy = 0; |
4471a34f VK |
196 | int rc; |
197 | ||
4d5dcc42 VK |
198 | if (have_governor_per_policy()) |
199 | dbs_data = policy->governor_data; | |
200 | else | |
201 | dbs_data = cdata->gdbs_data; | |
202 | ||
203 | WARN_ON(!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT)); | |
204 | ||
205 | switch (event) { | |
206 | case CPUFREQ_GOV_POLICY_INIT: | |
207 | if (have_governor_per_policy()) { | |
208 | WARN_ON(dbs_data); | |
209 | } else if (dbs_data) { | |
a97c98ad | 210 | dbs_data->usage_count++; |
4d5dcc42 VK |
211 | policy->governor_data = dbs_data; |
212 | return 0; | |
213 | } | |
214 | ||
215 | dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL); | |
216 | if (!dbs_data) { | |
217 | pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__); | |
218 | return -ENOMEM; | |
219 | } | |
220 | ||
221 | dbs_data->cdata = cdata; | |
a97c98ad | 222 | dbs_data->usage_count = 1; |
4d5dcc42 VK |
223 | rc = cdata->init(dbs_data); |
224 | if (rc) { | |
225 | pr_err("%s: POLICY_INIT: init() failed\n", __func__); | |
226 | kfree(dbs_data); | |
227 | return rc; | |
228 | } | |
229 | ||
2361be23 VK |
230 | if (!have_governor_per_policy()) |
231 | WARN_ON(cpufreq_get_global_kobject()); | |
232 | ||
4d5dcc42 VK |
233 | rc = sysfs_create_group(get_governor_parent_kobj(policy), |
234 | get_sysfs_attr(dbs_data)); | |
235 | if (rc) { | |
236 | cdata->exit(dbs_data); | |
237 | kfree(dbs_data); | |
238 | return rc; | |
239 | } | |
240 | ||
241 | policy->governor_data = dbs_data; | |
242 | ||
c4afc410 | 243 | /* policy latency is in ns. Convert it to us first */ |
4d5dcc42 VK |
244 | latency = policy->cpuinfo.transition_latency / 1000; |
245 | if (latency == 0) | |
246 | latency = 1; | |
247 | ||
248 | /* Bring kernel and HW constraints together */ | |
249 | dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate, | |
250 | MIN_LATENCY_MULTIPLIER * latency); | |
251 | set_sampling_rate(dbs_data, max(dbs_data->min_sampling_rate, | |
252 | latency * LATENCY_MULTIPLIER)); | |
253 | ||
a97c98ad VK |
254 | if ((cdata->governor == GOV_CONSERVATIVE) && |
255 | (!policy->governor->initialized)) { | |
4d5dcc42 VK |
256 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; |
257 | ||
258 | cpufreq_register_notifier(cs_ops->notifier_block, | |
259 | CPUFREQ_TRANSITION_NOTIFIER); | |
260 | } | |
261 | ||
262 | if (!have_governor_per_policy()) | |
263 | cdata->gdbs_data = dbs_data; | |
264 | ||
265 | return 0; | |
266 | case CPUFREQ_GOV_POLICY_EXIT: | |
a97c98ad | 267 | if (!--dbs_data->usage_count) { |
4d5dcc42 VK |
268 | sysfs_remove_group(get_governor_parent_kobj(policy), |
269 | get_sysfs_attr(dbs_data)); | |
270 | ||
2361be23 VK |
271 | if (!have_governor_per_policy()) |
272 | cpufreq_put_global_kobject(); | |
273 | ||
a97c98ad VK |
274 | if ((dbs_data->cdata->governor == GOV_CONSERVATIVE) && |
275 | (policy->governor->initialized == 1)) { | |
4d5dcc42 VK |
276 | struct cs_ops *cs_ops = dbs_data->cdata->gov_ops; |
277 | ||
278 | cpufreq_unregister_notifier(cs_ops->notifier_block, | |
279 | CPUFREQ_TRANSITION_NOTIFIER); | |
280 | } | |
281 | ||
282 | cdata->exit(dbs_data); | |
283 | kfree(dbs_data); | |
284 | cdata->gdbs_data = NULL; | |
285 | } | |
4471a34f | 286 | |
4d5dcc42 VK |
287 | policy->governor_data = NULL; |
288 | return 0; | |
289 | } | |
290 | ||
291 | cpu_cdbs = dbs_data->cdata->get_cpu_cdbs(cpu); | |
292 | ||
293 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { | |
294 | cs_tuners = dbs_data->tuners; | |
295 | cs_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
296 | sampling_rate = cs_tuners->sampling_rate; | |
6c4640c3 | 297 | ignore_nice = cs_tuners->ignore_nice_load; |
4471a34f | 298 | } else { |
4d5dcc42 VK |
299 | od_tuners = dbs_data->tuners; |
300 | od_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu); | |
301 | sampling_rate = od_tuners->sampling_rate; | |
6c4640c3 | 302 | ignore_nice = od_tuners->ignore_nice_load; |
4d5dcc42 | 303 | od_ops = dbs_data->cdata->gov_ops; |
9366d840 | 304 | io_busy = od_tuners->io_is_busy; |
4471a34f VK |
305 | } |
306 | ||
307 | switch (event) { | |
308 | case CPUFREQ_GOV_START: | |
3361b7b1 | 309 | if (!policy->cur) |
4471a34f VK |
310 | return -EINVAL; |
311 | ||
312 | mutex_lock(&dbs_data->mutex); | |
313 | ||
4471a34f | 314 | for_each_cpu(j, policy->cpus) { |
8eeed095 | 315 | struct cpu_dbs_common_info *j_cdbs = |
4d5dcc42 | 316 | dbs_data->cdata->get_cpu_cdbs(j); |
4471a34f | 317 | |
09dca5ae | 318 | j_cdbs->cpu = j; |
4471a34f VK |
319 | j_cdbs->cur_policy = policy; |
320 | j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, | |
9366d840 | 321 | &j_cdbs->prev_cpu_wall, io_busy); |
4471a34f VK |
322 | if (ignore_nice) |
323 | j_cdbs->prev_cpu_nice = | |
324 | kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
2abfa876 RA |
325 | |
326 | mutex_init(&j_cdbs->timer_mutex); | |
327 | INIT_DEFERRABLE_WORK(&j_cdbs->work, | |
4d5dcc42 | 328 | dbs_data->cdata->gov_dbs_timer); |
4471a34f VK |
329 | } |
330 | ||
4471a34f VK |
331 | /* |
332 | * conservative does not implement micro like ondemand | |
333 | * governor, thus we are bound to jiffes/HZ | |
334 | */ | |
4d5dcc42 | 335 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { |
8eeed095 VK |
336 | cs_dbs_info->down_skip = 0; |
337 | cs_dbs_info->enable = 1; | |
338 | cs_dbs_info->requested_freq = policy->cur; | |
4471a34f | 339 | } else { |
8eeed095 VK |
340 | od_dbs_info->rate_mult = 1; |
341 | od_dbs_info->sample_type = OD_NORMAL_SAMPLE; | |
342 | od_ops->powersave_bias_init_cpu(cpu); | |
4471a34f VK |
343 | } |
344 | ||
4471a34f VK |
345 | mutex_unlock(&dbs_data->mutex); |
346 | ||
58ddcead FB |
347 | /* Initiate timer time stamp */ |
348 | cpu_cdbs->time_stamp = ktime_get(); | |
da53d61e | 349 | |
031299b3 VK |
350 | gov_queue_work(dbs_data, policy, |
351 | delay_for_sampling_rate(sampling_rate), true); | |
4471a34f VK |
352 | break; |
353 | ||
354 | case CPUFREQ_GOV_STOP: | |
4d5dcc42 | 355 | if (dbs_data->cdata->governor == GOV_CONSERVATIVE) |
4471a34f VK |
356 | cs_dbs_info->enable = 0; |
357 | ||
031299b3 | 358 | gov_cancel_work(dbs_data, policy); |
4471a34f VK |
359 | |
360 | mutex_lock(&dbs_data->mutex); | |
361 | mutex_destroy(&cpu_cdbs->timer_mutex); | |
419e1721 | 362 | cpu_cdbs->cur_policy = NULL; |
8eeed095 | 363 | |
4471a34f VK |
364 | mutex_unlock(&dbs_data->mutex); |
365 | ||
366 | break; | |
367 | ||
368 | case CPUFREQ_GOV_LIMITS: | |
369 | mutex_lock(&cpu_cdbs->timer_mutex); | |
370 | if (policy->max < cpu_cdbs->cur_policy->cur) | |
371 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
372 | policy->max, CPUFREQ_RELATION_H); | |
373 | else if (policy->min > cpu_cdbs->cur_policy->cur) | |
374 | __cpufreq_driver_target(cpu_cdbs->cur_policy, | |
375 | policy->min, CPUFREQ_RELATION_L); | |
376 | dbs_check_cpu(dbs_data, cpu); | |
377 | mutex_unlock(&cpu_cdbs->timer_mutex); | |
378 | break; | |
379 | } | |
380 | return 0; | |
381 | } | |
382 | EXPORT_SYMBOL_GPL(cpufreq_governor_dbs); |