]>
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 | ||
2bb8d94f RW |
25 | DEFINE_MUTEX(dbs_data_mutex); |
26 | EXPORT_SYMBOL_GPL(dbs_data_mutex); | |
27 | ||
aded387b VK |
28 | /* Common sysfs tunables */ |
29 | /** | |
30 | * store_sampling_rate - update sampling rate effective immediately if needed. | |
31 | * | |
32 | * If new rate is smaller than the old, simply updating | |
33 | * dbs.sampling_rate might not be appropriate. For example, if the | |
34 | * original sampling_rate was 1 second and the requested new sampling rate is 10 | |
35 | * ms because the user needs immediate reaction from ondemand governor, but not | |
36 | * sure if higher frequency will be required or not, then, the governor may | |
37 | * change the sampling rate too late; up to 1 second later. Thus, if we are | |
38 | * reducing the sampling rate, we need to make the new value effective | |
39 | * immediately. | |
40 | * | |
aded387b VK |
41 | * This must be called with dbs_data->mutex held, otherwise traversing |
42 | * policy_dbs_list isn't safe. | |
43 | */ | |
44 | ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf, | |
45 | size_t count) | |
46 | { | |
47 | struct policy_dbs_info *policy_dbs; | |
48 | unsigned int rate; | |
49 | int ret; | |
50 | ret = sscanf(buf, "%u", &rate); | |
51 | if (ret != 1) | |
52 | return -EINVAL; | |
53 | ||
54 | dbs_data->sampling_rate = max(rate, dbs_data->min_sampling_rate); | |
55 | ||
56 | /* | |
57 | * We are operating under dbs_data->mutex and so the list and its | |
58 | * entries can't be freed concurrently. | |
59 | */ | |
60 | list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) { | |
61 | mutex_lock(&policy_dbs->timer_mutex); | |
62 | /* | |
63 | * On 32-bit architectures this may race with the | |
64 | * sample_delay_ns read in dbs_update_util_handler(), but that | |
65 | * really doesn't matter. If the read returns a value that's | |
66 | * too big, the sample will be skipped, but the next invocation | |
67 | * of dbs_update_util_handler() (when the update has been | |
78347cdb | 68 | * completed) will take a sample. |
aded387b VK |
69 | * |
70 | * If this runs in parallel with dbs_work_handler(), we may end | |
71 | * up overwriting the sample_delay_ns value that it has just | |
78347cdb RW |
72 | * written, but it will be corrected next time a sample is |
73 | * taken, so it shouldn't be significant. | |
aded387b | 74 | */ |
78347cdb | 75 | gov_update_sample_delay(policy_dbs, 0); |
aded387b VK |
76 | mutex_unlock(&policy_dbs->timer_mutex); |
77 | } | |
78 | ||
79 | return count; | |
80 | } | |
81 | EXPORT_SYMBOL_GPL(store_sampling_rate); | |
82 | ||
c4435630 | 83 | static inline struct dbs_data *to_dbs_data(struct kobject *kobj) |
4d5dcc42 | 84 | { |
c4435630 | 85 | return container_of(kobj, struct dbs_data, kobj); |
4d5dcc42 VK |
86 | } |
87 | ||
c4435630 VK |
88 | static inline struct governor_attr *to_gov_attr(struct attribute *attr) |
89 | { | |
90 | return container_of(attr, struct governor_attr, attr); | |
91 | } | |
92 | ||
93 | static ssize_t governor_show(struct kobject *kobj, struct attribute *attr, | |
94 | char *buf) | |
95 | { | |
96 | struct dbs_data *dbs_data = to_dbs_data(kobj); | |
97 | struct governor_attr *gattr = to_gov_attr(attr); | |
98 | int ret = -EIO; | |
99 | ||
100 | if (gattr->show) | |
101 | ret = gattr->show(dbs_data, buf); | |
102 | ||
103 | return ret; | |
104 | } | |
105 | ||
106 | static ssize_t governor_store(struct kobject *kobj, struct attribute *attr, | |
107 | const char *buf, size_t count) | |
108 | { | |
109 | struct dbs_data *dbs_data = to_dbs_data(kobj); | |
110 | struct governor_attr *gattr = to_gov_attr(attr); | |
111 | int ret = -EIO; | |
112 | ||
113 | mutex_lock(&dbs_data->mutex); | |
114 | ||
574ef14d | 115 | if (dbs_data->usage_count && gattr->store) |
c4435630 VK |
116 | ret = gattr->store(dbs_data, buf, count); |
117 | ||
118 | mutex_unlock(&dbs_data->mutex); | |
119 | ||
120 | return ret; | |
121 | } | |
122 | ||
123 | /* | |
124 | * Sysfs Ops for accessing governor attributes. | |
125 | * | |
126 | * All show/store invocations for governor specific sysfs attributes, will first | |
127 | * call the below show/store callbacks and the attribute specific callback will | |
128 | * be called from within it. | |
129 | */ | |
130 | static const struct sysfs_ops governor_sysfs_ops = { | |
131 | .show = governor_show, | |
132 | .store = governor_store, | |
133 | }; | |
134 | ||
4cccf755 | 135 | unsigned int dbs_update(struct cpufreq_policy *policy) |
4471a34f | 136 | { |
ea59ee0d | 137 | struct dbs_governor *gov = dbs_governor_of(policy); |
bc505475 RW |
138 | struct policy_dbs_info *policy_dbs = policy->governor_data; |
139 | struct dbs_data *dbs_data = policy_dbs->dbs_data; | |
ff4b1789 | 140 | unsigned int ignore_nice = dbs_data->ignore_nice_load; |
4471a34f | 141 | unsigned int max_load = 0; |
8847e038 | 142 | unsigned int sampling_rate, io_busy, j; |
4471a34f | 143 | |
57dc3bcd RW |
144 | /* |
145 | * Sometimes governors may use an additional multiplier to increase | |
146 | * sample delays temporarily. Apply that multiplier to sampling_rate | |
147 | * so as to keep the wake-up-from-idle detection logic a bit | |
148 | * conservative. | |
149 | */ | |
150 | sampling_rate = dbs_data->sampling_rate * policy_dbs->rate_mult; | |
8847e038 RW |
151 | /* |
152 | * For the purpose of ondemand, waiting for disk IO is an indication | |
153 | * that you're performance critical, and not that the system is actually | |
154 | * idle, so do not add the iowait time to the CPU idle time then. | |
155 | */ | |
156 | io_busy = dbs_data->io_is_busy; | |
4471a34f | 157 | |
dfa5bb62 | 158 | /* Get Absolute Load */ |
4471a34f | 159 | for_each_cpu(j, policy->cpus) { |
875b8508 | 160 | struct cpu_dbs_info *j_cdbs; |
9366d840 SK |
161 | u64 cur_wall_time, cur_idle_time; |
162 | unsigned int idle_time, wall_time; | |
4471a34f VK |
163 | unsigned int load; |
164 | ||
ea59ee0d | 165 | j_cdbs = gov->get_cpu_cdbs(j); |
4471a34f | 166 | |
9366d840 | 167 | cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy); |
4471a34f | 168 | |
57eb832f | 169 | wall_time = cur_wall_time - j_cdbs->prev_cpu_wall; |
4471a34f VK |
170 | j_cdbs->prev_cpu_wall = cur_wall_time; |
171 | ||
57eb832f RW |
172 | if (cur_idle_time <= j_cdbs->prev_cpu_idle) { |
173 | idle_time = 0; | |
174 | } else { | |
175 | idle_time = cur_idle_time - j_cdbs->prev_cpu_idle; | |
176 | j_cdbs->prev_cpu_idle = cur_idle_time; | |
177 | } | |
4471a34f VK |
178 | |
179 | if (ignore_nice) { | |
679b8fe4 RW |
180 | u64 cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; |
181 | ||
182 | idle_time += cputime_to_usecs(cur_nice - j_cdbs->prev_cpu_nice); | |
183 | j_cdbs->prev_cpu_nice = cur_nice; | |
4471a34f VK |
184 | } |
185 | ||
4471a34f VK |
186 | if (unlikely(!wall_time || wall_time < idle_time)) |
187 | continue; | |
188 | ||
18b46abd SB |
189 | /* |
190 | * If the CPU had gone completely idle, and a task just woke up | |
191 | * on this CPU now, it would be unfair to calculate 'load' the | |
192 | * usual way for this elapsed time-window, because it will show | |
193 | * near-zero load, irrespective of how CPU intensive that task | |
194 | * actually is. This is undesirable for latency-sensitive bursty | |
195 | * workloads. | |
196 | * | |
197 | * To avoid this, we reuse the 'load' from the previous | |
198 | * time-window and give this task a chance to start with a | |
199 | * reasonably high CPU frequency. (However, we shouldn't over-do | |
200 | * this copy, lest we get stuck at a high load (high frequency) | |
201 | * for too long, even when the current system load has actually | |
202 | * dropped down. So we perform the copy only once, upon the | |
203 | * first wake-up from idle.) | |
204 | * | |
9be4fd2c RW |
205 | * Detecting this situation is easy: the governor's utilization |
206 | * update handler would not have run during CPU-idle periods. | |
207 | * Hence, an unusually large 'wall_time' (as compared to the | |
208 | * sampling rate) indicates this scenario. | |
c8ae481b VK |
209 | * |
210 | * prev_load can be zero in two cases and we must recalculate it | |
211 | * for both cases: | |
212 | * - during long idle intervals | |
213 | * - explicitly set to zero | |
18b46abd | 214 | */ |
c8ae481b VK |
215 | if (unlikely(wall_time > (2 * sampling_rate) && |
216 | j_cdbs->prev_load)) { | |
18b46abd | 217 | load = j_cdbs->prev_load; |
c8ae481b VK |
218 | |
219 | /* | |
220 | * Perform a destructive copy, to ensure that we copy | |
221 | * the previous load only once, upon the first wake-up | |
222 | * from idle. | |
223 | */ | |
224 | j_cdbs->prev_load = 0; | |
18b46abd SB |
225 | } else { |
226 | load = 100 * (wall_time - idle_time) / wall_time; | |
227 | j_cdbs->prev_load = load; | |
18b46abd | 228 | } |
4471a34f | 229 | |
4471a34f VK |
230 | if (load > max_load) |
231 | max_load = load; | |
232 | } | |
4cccf755 | 233 | return max_load; |
4471a34f | 234 | } |
4cccf755 | 235 | EXPORT_SYMBOL_GPL(dbs_update); |
4471a34f | 236 | |
e40e7b25 | 237 | void gov_set_update_util(struct policy_dbs_info *policy_dbs, |
9be4fd2c | 238 | unsigned int delay_us) |
4471a34f | 239 | { |
e40e7b25 | 240 | struct cpufreq_policy *policy = policy_dbs->policy; |
ea59ee0d | 241 | struct dbs_governor *gov = dbs_governor_of(policy); |
70f43e5e | 242 | int cpu; |
031299b3 | 243 | |
e40e7b25 RW |
244 | gov_update_sample_delay(policy_dbs, delay_us); |
245 | policy_dbs->last_sample_time = 0; | |
9be4fd2c | 246 | |
70f43e5e | 247 | for_each_cpu(cpu, policy->cpus) { |
ea59ee0d | 248 | struct cpu_dbs_info *cdbs = gov->get_cpu_cdbs(cpu); |
9be4fd2c RW |
249 | |
250 | cpufreq_set_update_util_data(cpu, &cdbs->update_util); | |
031299b3 VK |
251 | } |
252 | } | |
9be4fd2c | 253 | EXPORT_SYMBOL_GPL(gov_set_update_util); |
031299b3 | 254 | |
9be4fd2c | 255 | static inline void gov_clear_update_util(struct cpufreq_policy *policy) |
031299b3 | 256 | { |
031299b3 | 257 | int i; |
58ddcead | 258 | |
9be4fd2c RW |
259 | for_each_cpu(i, policy->cpus) |
260 | cpufreq_set_update_util_data(i, NULL); | |
261 | ||
262 | synchronize_rcu(); | |
4471a34f VK |
263 | } |
264 | ||
581c214b | 265 | static void gov_cancel_work(struct cpufreq_policy *policy) |
70f43e5e | 266 | { |
581c214b VK |
267 | struct policy_dbs_info *policy_dbs = policy->governor_data; |
268 | ||
e40e7b25 RW |
269 | gov_clear_update_util(policy_dbs->policy); |
270 | irq_work_sync(&policy_dbs->irq_work); | |
271 | cancel_work_sync(&policy_dbs->work); | |
686cc637 | 272 | atomic_set(&policy_dbs->work_count, 0); |
e4db2813 | 273 | policy_dbs->work_in_progress = false; |
70f43e5e | 274 | } |
43e0ee36 | 275 | |
70f43e5e | 276 | static void dbs_work_handler(struct work_struct *work) |
43e0ee36 | 277 | { |
e40e7b25 | 278 | struct policy_dbs_info *policy_dbs; |
3a91b069 | 279 | struct cpufreq_policy *policy; |
ea59ee0d | 280 | struct dbs_governor *gov; |
43e0ee36 | 281 | |
e40e7b25 RW |
282 | policy_dbs = container_of(work, struct policy_dbs_info, work); |
283 | policy = policy_dbs->policy; | |
ea59ee0d | 284 | gov = dbs_governor_of(policy); |
3a91b069 | 285 | |
70f43e5e | 286 | /* |
9be4fd2c RW |
287 | * Make sure cpufreq_governor_limits() isn't evaluating load or the |
288 | * ondemand governor isn't updating the sampling rate in parallel. | |
70f43e5e | 289 | */ |
e40e7b25 | 290 | mutex_lock(&policy_dbs->timer_mutex); |
07aa4402 | 291 | gov_update_sample_delay(policy_dbs, gov->gov_dbs_timer(policy)); |
e40e7b25 | 292 | mutex_unlock(&policy_dbs->timer_mutex); |
70f43e5e | 293 | |
e4db2813 RW |
294 | /* Allow the utilization update handler to queue up more work. */ |
295 | atomic_set(&policy_dbs->work_count, 0); | |
9be4fd2c | 296 | /* |
e4db2813 RW |
297 | * If the update below is reordered with respect to the sample delay |
298 | * modification, the utilization update handler may end up using a stale | |
299 | * sample delay value. | |
9be4fd2c | 300 | */ |
e4db2813 RW |
301 | smp_wmb(); |
302 | policy_dbs->work_in_progress = false; | |
9be4fd2c RW |
303 | } |
304 | ||
305 | static void dbs_irq_work(struct irq_work *irq_work) | |
306 | { | |
e40e7b25 | 307 | struct policy_dbs_info *policy_dbs; |
70f43e5e | 308 | |
e40e7b25 RW |
309 | policy_dbs = container_of(irq_work, struct policy_dbs_info, irq_work); |
310 | schedule_work(&policy_dbs->work); | |
70f43e5e VK |
311 | } |
312 | ||
9be4fd2c RW |
313 | static void dbs_update_util_handler(struct update_util_data *data, u64 time, |
314 | unsigned long util, unsigned long max) | |
315 | { | |
316 | struct cpu_dbs_info *cdbs = container_of(data, struct cpu_dbs_info, update_util); | |
e40e7b25 | 317 | struct policy_dbs_info *policy_dbs = cdbs->policy_dbs; |
e4db2813 | 318 | u64 delta_ns; |
70f43e5e VK |
319 | |
320 | /* | |
9be4fd2c RW |
321 | * The work may not be allowed to be queued up right now. |
322 | * Possible reasons: | |
323 | * - Work has already been queued up or is in progress. | |
9be4fd2c | 324 | * - It is too early (too little time from the previous sample). |
70f43e5e | 325 | */ |
e4db2813 RW |
326 | if (policy_dbs->work_in_progress) |
327 | return; | |
328 | ||
329 | /* | |
330 | * If the reads below are reordered before the check above, the value | |
331 | * of sample_delay_ns used in the computation may be stale. | |
332 | */ | |
333 | smp_rmb(); | |
334 | delta_ns = time - policy_dbs->last_sample_time; | |
335 | if ((s64)delta_ns < policy_dbs->sample_delay_ns) | |
336 | return; | |
337 | ||
338 | /* | |
339 | * If the policy is not shared, the irq_work may be queued up right away | |
340 | * at this point. Otherwise, we need to ensure that only one of the | |
341 | * CPUs sharing the policy will do that. | |
342 | */ | |
343 | if (policy_dbs->is_shared && | |
344 | !atomic_add_unless(&policy_dbs->work_count, 1, 1)) | |
345 | return; | |
346 | ||
347 | policy_dbs->last_sample_time = time; | |
348 | policy_dbs->work_in_progress = true; | |
349 | irq_work_queue(&policy_dbs->irq_work); | |
43e0ee36 | 350 | } |
4447266b | 351 | |
bc505475 RW |
352 | static struct policy_dbs_info *alloc_policy_dbs_info(struct cpufreq_policy *policy, |
353 | struct dbs_governor *gov) | |
44152cb8 | 354 | { |
e40e7b25 | 355 | struct policy_dbs_info *policy_dbs; |
44152cb8 VK |
356 | int j; |
357 | ||
358 | /* Allocate memory for the common information for policy->cpus */ | |
e40e7b25 RW |
359 | policy_dbs = kzalloc(sizeof(*policy_dbs), GFP_KERNEL); |
360 | if (!policy_dbs) | |
bc505475 | 361 | return NULL; |
44152cb8 | 362 | |
581c214b | 363 | policy_dbs->policy = policy; |
e40e7b25 | 364 | mutex_init(&policy_dbs->timer_mutex); |
686cc637 | 365 | atomic_set(&policy_dbs->work_count, 0); |
e40e7b25 RW |
366 | init_irq_work(&policy_dbs->irq_work, dbs_irq_work); |
367 | INIT_WORK(&policy_dbs->work, dbs_work_handler); | |
cea6a9e7 RW |
368 | |
369 | /* Set policy_dbs for all CPUs, online+offline */ | |
370 | for_each_cpu(j, policy->related_cpus) { | |
371 | struct cpu_dbs_info *j_cdbs = gov->get_cpu_cdbs(j); | |
372 | ||
373 | j_cdbs->policy_dbs = policy_dbs; | |
374 | j_cdbs->update_util.func = dbs_update_util_handler; | |
375 | } | |
bc505475 | 376 | return policy_dbs; |
44152cb8 VK |
377 | } |
378 | ||
e40e7b25 | 379 | static void free_policy_dbs_info(struct cpufreq_policy *policy, |
7bdad34d | 380 | struct dbs_governor *gov) |
44152cb8 | 381 | { |
7bdad34d | 382 | struct cpu_dbs_info *cdbs = gov->get_cpu_cdbs(policy->cpu); |
e40e7b25 | 383 | struct policy_dbs_info *policy_dbs = cdbs->policy_dbs; |
44152cb8 VK |
384 | int j; |
385 | ||
e40e7b25 | 386 | mutex_destroy(&policy_dbs->timer_mutex); |
5e4500d8 | 387 | |
cea6a9e7 RW |
388 | for_each_cpu(j, policy->related_cpus) { |
389 | struct cpu_dbs_info *j_cdbs = gov->get_cpu_cdbs(j); | |
44152cb8 | 390 | |
cea6a9e7 RW |
391 | j_cdbs->policy_dbs = NULL; |
392 | j_cdbs->update_util.func = NULL; | |
393 | } | |
e40e7b25 | 394 | kfree(policy_dbs); |
44152cb8 VK |
395 | } |
396 | ||
906a6e5a | 397 | static int cpufreq_governor_init(struct cpufreq_policy *policy) |
4471a34f | 398 | { |
ea59ee0d | 399 | struct dbs_governor *gov = dbs_governor_of(policy); |
7bdad34d | 400 | struct dbs_data *dbs_data = gov->gdbs_data; |
bc505475 | 401 | struct policy_dbs_info *policy_dbs; |
714a2d9c VK |
402 | unsigned int latency; |
403 | int ret; | |
4471a34f | 404 | |
a72c4959 VK |
405 | /* State should be equivalent to EXIT */ |
406 | if (policy->governor_data) | |
407 | return -EBUSY; | |
408 | ||
bc505475 RW |
409 | policy_dbs = alloc_policy_dbs_info(policy, gov); |
410 | if (!policy_dbs) | |
411 | return -ENOMEM; | |
44152cb8 | 412 | |
bc505475 RW |
413 | if (dbs_data) { |
414 | if (WARN_ON(have_governor_per_policy())) { | |
415 | ret = -EINVAL; | |
416 | goto free_policy_dbs_info; | |
417 | } | |
bc505475 RW |
418 | policy_dbs->dbs_data = dbs_data; |
419 | policy->governor_data = policy_dbs; | |
c54df071 VK |
420 | |
421 | mutex_lock(&dbs_data->mutex); | |
422 | dbs_data->usage_count++; | |
423 | list_add(&policy_dbs->list, &dbs_data->policy_dbs_list); | |
424 | mutex_unlock(&dbs_data->mutex); | |
425 | ||
714a2d9c VK |
426 | return 0; |
427 | } | |
4d5dcc42 | 428 | |
714a2d9c | 429 | dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL); |
bc505475 RW |
430 | if (!dbs_data) { |
431 | ret = -ENOMEM; | |
432 | goto free_policy_dbs_info; | |
433 | } | |
44152cb8 | 434 | |
c54df071 | 435 | INIT_LIST_HEAD(&dbs_data->policy_dbs_list); |
c4435630 | 436 | mutex_init(&dbs_data->mutex); |
4d5dcc42 | 437 | |
7bdad34d | 438 | ret = gov->init(dbs_data, !policy->governor->initialized); |
714a2d9c | 439 | if (ret) |
e40e7b25 | 440 | goto free_policy_dbs_info; |
4d5dcc42 | 441 | |
714a2d9c VK |
442 | /* policy latency is in ns. Convert it to us first */ |
443 | latency = policy->cpuinfo.transition_latency / 1000; | |
444 | if (latency == 0) | |
445 | latency = 1; | |
4d5dcc42 | 446 | |
714a2d9c VK |
447 | /* Bring kernel and HW constraints together */ |
448 | dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate, | |
449 | MIN_LATENCY_MULTIPLIER * latency); | |
ff4b1789 VK |
450 | dbs_data->sampling_rate = max(dbs_data->min_sampling_rate, |
451 | LATENCY_MULTIPLIER * latency); | |
2361be23 | 452 | |
8eec1020 | 453 | if (!have_governor_per_policy()) |
7bdad34d | 454 | gov->gdbs_data = dbs_data; |
4d5dcc42 | 455 | |
bc505475 | 456 | policy->governor_data = policy_dbs; |
e4b133cc | 457 | |
c54df071 VK |
458 | policy_dbs->dbs_data = dbs_data; |
459 | dbs_data->usage_count = 1; | |
460 | list_add(&policy_dbs->list, &dbs_data->policy_dbs_list); | |
461 | ||
c4435630 VK |
462 | gov->kobj_type.sysfs_ops = &governor_sysfs_ops; |
463 | ret = kobject_init_and_add(&dbs_data->kobj, &gov->kobj_type, | |
464 | get_governor_parent_kobj(policy), | |
465 | "%s", gov->gov.name); | |
fafd5e8a RW |
466 | if (!ret) |
467 | return 0; | |
4d5dcc42 | 468 | |
fafd5e8a | 469 | /* Failure, so roll back. */ |
c4435630 | 470 | pr_err("cpufreq: Governor initialization failed (dbs_data kobject init error %d)\n", ret); |
4d5dcc42 | 471 | |
e4b133cc VK |
472 | policy->governor_data = NULL; |
473 | ||
8eec1020 | 474 | if (!have_governor_per_policy()) |
7bdad34d RW |
475 | gov->gdbs_data = NULL; |
476 | gov->exit(dbs_data, !policy->governor->initialized); | |
bc505475 RW |
477 | kfree(dbs_data); |
478 | ||
e40e7b25 RW |
479 | free_policy_dbs_info: |
480 | free_policy_dbs_info(policy, gov); | |
714a2d9c VK |
481 | return ret; |
482 | } | |
4d5dcc42 | 483 | |
5da3dd1e | 484 | static int cpufreq_governor_exit(struct cpufreq_policy *policy) |
714a2d9c | 485 | { |
ea59ee0d | 486 | struct dbs_governor *gov = dbs_governor_of(policy); |
bc505475 RW |
487 | struct policy_dbs_info *policy_dbs = policy->governor_data; |
488 | struct dbs_data *dbs_data = policy_dbs->dbs_data; | |
c54df071 | 489 | int count; |
a72c4959 | 490 | |
c54df071 VK |
491 | mutex_lock(&dbs_data->mutex); |
492 | list_del(&policy_dbs->list); | |
493 | count = --dbs_data->usage_count; | |
494 | mutex_unlock(&dbs_data->mutex); | |
495 | ||
496 | if (!count) { | |
c4435630 | 497 | kobject_put(&dbs_data->kobj); |
2361be23 | 498 | |
e4b133cc VK |
499 | policy->governor_data = NULL; |
500 | ||
8eec1020 | 501 | if (!have_governor_per_policy()) |
7bdad34d | 502 | gov->gdbs_data = NULL; |
4471a34f | 503 | |
7bdad34d | 504 | gov->exit(dbs_data, policy->governor->initialized == 1); |
c4435630 | 505 | mutex_destroy(&dbs_data->mutex); |
714a2d9c | 506 | kfree(dbs_data); |
e4b133cc VK |
507 | } else { |
508 | policy->governor_data = NULL; | |
4d5dcc42 | 509 | } |
44152cb8 | 510 | |
e40e7b25 | 511 | free_policy_dbs_info(policy, gov); |
a72c4959 | 512 | return 0; |
714a2d9c | 513 | } |
4d5dcc42 | 514 | |
5da3dd1e | 515 | static int cpufreq_governor_start(struct cpufreq_policy *policy) |
714a2d9c | 516 | { |
ea59ee0d | 517 | struct dbs_governor *gov = dbs_governor_of(policy); |
bc505475 RW |
518 | struct policy_dbs_info *policy_dbs = policy->governor_data; |
519 | struct dbs_data *dbs_data = policy_dbs->dbs_data; | |
714a2d9c | 520 | unsigned int sampling_rate, ignore_nice, j, cpu = policy->cpu; |
8847e038 | 521 | unsigned int io_busy; |
714a2d9c VK |
522 | |
523 | if (!policy->cur) | |
524 | return -EINVAL; | |
525 | ||
e4db2813 | 526 | policy_dbs->is_shared = policy_is_shared(policy); |
57dc3bcd | 527 | policy_dbs->rate_mult = 1; |
e4db2813 | 528 | |
ff4b1789 VK |
529 | sampling_rate = dbs_data->sampling_rate; |
530 | ignore_nice = dbs_data->ignore_nice_load; | |
8847e038 | 531 | io_busy = dbs_data->io_is_busy; |
4471a34f | 532 | |
714a2d9c | 533 | for_each_cpu(j, policy->cpus) { |
7bdad34d | 534 | struct cpu_dbs_info *j_cdbs = gov->get_cpu_cdbs(j); |
714a2d9c | 535 | unsigned int prev_load; |
4471a34f | 536 | |
57eb832f | 537 | j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, &j_cdbs->prev_cpu_wall, io_busy); |
4471a34f | 538 | |
57eb832f RW |
539 | prev_load = j_cdbs->prev_cpu_wall - j_cdbs->prev_cpu_idle; |
540 | j_cdbs->prev_load = 100 * prev_load / (unsigned int)j_cdbs->prev_cpu_wall; | |
18b46abd | 541 | |
714a2d9c VK |
542 | if (ignore_nice) |
543 | j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; | |
714a2d9c | 544 | } |
2abfa876 | 545 | |
7bdad34d | 546 | if (gov->governor == GOV_CONSERVATIVE) { |
714a2d9c | 547 | struct cs_cpu_dbs_info_s *cs_dbs_info = |
7bdad34d | 548 | gov->get_cpu_dbs_info_s(cpu); |
4471a34f | 549 | |
714a2d9c | 550 | cs_dbs_info->down_skip = 0; |
714a2d9c VK |
551 | cs_dbs_info->requested_freq = policy->cur; |
552 | } else { | |
7bdad34d RW |
553 | struct od_ops *od_ops = gov->gov_ops; |
554 | struct od_cpu_dbs_info_s *od_dbs_info = gov->get_cpu_dbs_info_s(cpu); | |
4471a34f | 555 | |
714a2d9c VK |
556 | od_dbs_info->sample_type = OD_NORMAL_SAMPLE; |
557 | od_ops->powersave_bias_init_cpu(cpu); | |
558 | } | |
4471a34f | 559 | |
e40e7b25 | 560 | gov_set_update_util(policy_dbs, sampling_rate); |
714a2d9c VK |
561 | return 0; |
562 | } | |
563 | ||
5da3dd1e | 564 | static int cpufreq_governor_stop(struct cpufreq_policy *policy) |
714a2d9c | 565 | { |
581c214b | 566 | gov_cancel_work(policy); |
3a91b069 | 567 | |
a72c4959 | 568 | return 0; |
714a2d9c | 569 | } |
4471a34f | 570 | |
5da3dd1e | 571 | static int cpufreq_governor_limits(struct cpufreq_policy *policy) |
714a2d9c | 572 | { |
bc505475 | 573 | struct policy_dbs_info *policy_dbs = policy->governor_data; |
8eeed095 | 574 | |
e9751894 | 575 | mutex_lock(&policy_dbs->timer_mutex); |
4cccf755 | 576 | |
e9751894 RW |
577 | if (policy->max < policy->cur) |
578 | __cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H); | |
579 | else if (policy->min > policy->cur) | |
580 | __cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L); | |
4cccf755 RW |
581 | |
582 | gov_update_sample_delay(policy_dbs, 0); | |
583 | ||
e9751894 | 584 | mutex_unlock(&policy_dbs->timer_mutex); |
a72c4959 VK |
585 | |
586 | return 0; | |
714a2d9c | 587 | } |
4471a34f | 588 | |
906a6e5a | 589 | int cpufreq_governor_dbs(struct cpufreq_policy *policy, unsigned int event) |
714a2d9c | 590 | { |
5da3dd1e | 591 | int ret = -EINVAL; |
714a2d9c | 592 | |
732b6d61 | 593 | /* Lock governor to block concurrent initialization of governor */ |
2bb8d94f | 594 | mutex_lock(&dbs_data_mutex); |
732b6d61 | 595 | |
5da3dd1e | 596 | if (event == CPUFREQ_GOV_POLICY_INIT) { |
906a6e5a | 597 | ret = cpufreq_governor_init(policy); |
5da3dd1e RW |
598 | } else if (policy->governor_data) { |
599 | switch (event) { | |
600 | case CPUFREQ_GOV_POLICY_EXIT: | |
601 | ret = cpufreq_governor_exit(policy); | |
602 | break; | |
603 | case CPUFREQ_GOV_START: | |
604 | ret = cpufreq_governor_start(policy); | |
605 | break; | |
606 | case CPUFREQ_GOV_STOP: | |
607 | ret = cpufreq_governor_stop(policy); | |
608 | break; | |
609 | case CPUFREQ_GOV_LIMITS: | |
610 | ret = cpufreq_governor_limits(policy); | |
611 | break; | |
612 | } | |
4471a34f | 613 | } |
714a2d9c | 614 | |
2bb8d94f | 615 | mutex_unlock(&dbs_data_mutex); |
714a2d9c | 616 | return ret; |
4471a34f VK |
617 | } |
618 | EXPORT_SYMBOL_GPL(cpufreq_governor_dbs); |