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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * drivers/cpufreq/cpufreq_conservative.c
4 *
5 * Copyright (C) 2001 Russell King
6 * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
7 * Jun Nakajima <jun.nakajima@intel.com>
8 * (C) 2009 Alexander Clouter <alex@digriz.org.uk>
9 */
10
11#include <linux/slab.h>
12#include "cpufreq_governor.h"
13
14struct cs_policy_dbs_info {
15 struct policy_dbs_info policy_dbs;
16 unsigned int down_skip;
17 unsigned int requested_freq;
18};
19
20static inline struct cs_policy_dbs_info *to_dbs_info(struct policy_dbs_info *policy_dbs)
21{
22 return container_of(policy_dbs, struct cs_policy_dbs_info, policy_dbs);
23}
24
25struct cs_dbs_tuners {
26 unsigned int down_threshold;
27 unsigned int freq_step;
28};
29
30/* Conservative governor macros */
31#define DEF_FREQUENCY_UP_THRESHOLD (80)
32#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
33#define DEF_FREQUENCY_STEP (5)
34#define DEF_SAMPLING_DOWN_FACTOR (1)
35#define MAX_SAMPLING_DOWN_FACTOR (10)
36
37static inline unsigned int get_freq_step(struct cs_dbs_tuners *cs_tuners,
38 struct cpufreq_policy *policy)
39{
40 unsigned int freq_step = (cs_tuners->freq_step * policy->max) / 100;
41
42 /* max freq cannot be less than 100. But who knows... */
43 if (unlikely(freq_step == 0))
44 freq_step = DEF_FREQUENCY_STEP;
45
46 return freq_step;
47}
48
49/*
50 * Every sampling_rate, we check, if current idle time is less than 20%
51 * (default), then we try to increase frequency. Every sampling_rate *
52 * sampling_down_factor, we check, if current idle time is more than 80%
53 * (default), then we try to decrease frequency
54 *
55 * Frequency updates happen at minimum steps of 5% (default) of maximum
56 * frequency
57 */
58static unsigned int cs_dbs_update(struct cpufreq_policy *policy)
59{
60 struct policy_dbs_info *policy_dbs = policy->governor_data;
61 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy_dbs);
62 unsigned int requested_freq = dbs_info->requested_freq;
63 struct dbs_data *dbs_data = policy_dbs->dbs_data;
64 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
65 unsigned int load = dbs_update(policy);
66 unsigned int freq_step;
67
68 /*
69 * break out if we 'cannot' reduce the speed as the user might
70 * want freq_step to be zero
71 */
72 if (cs_tuners->freq_step == 0)
73 goto out;
74
75 /*
76 * If requested_freq is out of range, it is likely that the limits
77 * changed in the meantime, so fall back to current frequency in that
78 * case.
79 */
80 if (requested_freq > policy->max || requested_freq < policy->min) {
81 requested_freq = policy->cur;
82 dbs_info->requested_freq = requested_freq;
83 }
84
85 freq_step = get_freq_step(cs_tuners, policy);
86
87 /*
88 * Decrease requested_freq one freq_step for each idle period that
89 * we didn't update the frequency.
90 */
91 if (policy_dbs->idle_periods < UINT_MAX) {
92 unsigned int freq_steps = policy_dbs->idle_periods * freq_step;
93
94 if (requested_freq > policy->min + freq_steps)
95 requested_freq -= freq_steps;
96 else
97 requested_freq = policy->min;
98
99 policy_dbs->idle_periods = UINT_MAX;
100 }
101
102 /* Check for frequency increase */
103 if (load > dbs_data->up_threshold) {
104 dbs_info->down_skip = 0;
105
106 /* if we are already at full speed then break out early */
107 if (requested_freq == policy->max)
108 goto out;
109
110 requested_freq += freq_step;
111 if (requested_freq > policy->max)
112 requested_freq = policy->max;
113
114 __cpufreq_driver_target(policy, requested_freq, CPUFREQ_RELATION_H);
115 dbs_info->requested_freq = requested_freq;
116 goto out;
117 }
118
119 /* if sampling_down_factor is active break out early */
120 if (++dbs_info->down_skip < dbs_data->sampling_down_factor)
121 goto out;
122 dbs_info->down_skip = 0;
123
124 /* Check for frequency decrease */
125 if (load < cs_tuners->down_threshold) {
126 /*
127 * if we cannot reduce the frequency anymore, break out early
128 */
129 if (requested_freq == policy->min)
130 goto out;
131
132 if (requested_freq > freq_step)
133 requested_freq -= freq_step;
134 else
135 requested_freq = policy->min;
136
137 __cpufreq_driver_target(policy, requested_freq, CPUFREQ_RELATION_L);
138 dbs_info->requested_freq = requested_freq;
139 }
140
141 out:
142 return dbs_data->sampling_rate;
143}
144
145/************************** sysfs interface ************************/
146
147static ssize_t store_sampling_down_factor(struct gov_attr_set *attr_set,
148 const char *buf, size_t count)
149{
150 struct dbs_data *dbs_data = to_dbs_data(attr_set);
151 unsigned int input;
152 int ret;
153 ret = sscanf(buf, "%u", &input);
154
155 if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
156 return -EINVAL;
157
158 dbs_data->sampling_down_factor = input;
159 return count;
160}
161
162static ssize_t store_up_threshold(struct gov_attr_set *attr_set,
163 const char *buf, size_t count)
164{
165 struct dbs_data *dbs_data = to_dbs_data(attr_set);
166 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
167 unsigned int input;
168 int ret;
169 ret = sscanf(buf, "%u", &input);
170
171 if (ret != 1 || input > 100 || input <= cs_tuners->down_threshold)
172 return -EINVAL;
173
174 dbs_data->up_threshold = input;
175 return count;
176}
177
178static ssize_t store_down_threshold(struct gov_attr_set *attr_set,
179 const char *buf, size_t count)
180{
181 struct dbs_data *dbs_data = to_dbs_data(attr_set);
182 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
183 unsigned int input;
184 int ret;
185 ret = sscanf(buf, "%u", &input);
186
187 /* cannot be lower than 1 otherwise freq will not fall */
188 if (ret != 1 || input < 1 || input > 100 ||
189 input >= dbs_data->up_threshold)
190 return -EINVAL;
191
192 cs_tuners->down_threshold = input;
193 return count;
194}
195
196static ssize_t store_ignore_nice_load(struct gov_attr_set *attr_set,
197 const char *buf, size_t count)
198{
199 struct dbs_data *dbs_data = to_dbs_data(attr_set);
200 unsigned int input;
201 int ret;
202
203 ret = sscanf(buf, "%u", &input);
204 if (ret != 1)
205 return -EINVAL;
206
207 if (input > 1)
208 input = 1;
209
210 if (input == dbs_data->ignore_nice_load) /* nothing to do */
211 return count;
212
213 dbs_data->ignore_nice_load = input;
214
215 /* we need to re-evaluate prev_cpu_idle */
216 gov_update_cpu_data(dbs_data);
217
218 return count;
219}
220
221static ssize_t store_freq_step(struct gov_attr_set *attr_set, const char *buf,
222 size_t count)
223{
224 struct dbs_data *dbs_data = to_dbs_data(attr_set);
225 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
226 unsigned int input;
227 int ret;
228 ret = sscanf(buf, "%u", &input);
229
230 if (ret != 1)
231 return -EINVAL;
232
233 if (input > 100)
234 input = 100;
235
236 /*
237 * no need to test here if freq_step is zero as the user might actually
238 * want this, they would be crazy though :)
239 */
240 cs_tuners->freq_step = input;
241 return count;
242}
243
244gov_show_one_common(sampling_rate);
245gov_show_one_common(sampling_down_factor);
246gov_show_one_common(up_threshold);
247gov_show_one_common(ignore_nice_load);
248gov_show_one(cs, down_threshold);
249gov_show_one(cs, freq_step);
250
251gov_attr_rw(sampling_rate);
252gov_attr_rw(sampling_down_factor);
253gov_attr_rw(up_threshold);
254gov_attr_rw(ignore_nice_load);
255gov_attr_rw(down_threshold);
256gov_attr_rw(freq_step);
257
258static struct attribute *cs_attributes[] = {
259 &sampling_rate.attr,
260 &sampling_down_factor.attr,
261 &up_threshold.attr,
262 &down_threshold.attr,
263 &ignore_nice_load.attr,
264 &freq_step.attr,
265 NULL
266};
267
268/************************** sysfs end ************************/
269
270static struct policy_dbs_info *cs_alloc(void)
271{
272 struct cs_policy_dbs_info *dbs_info;
273
274 dbs_info = kzalloc(sizeof(*dbs_info), GFP_KERNEL);
275 return dbs_info ? &dbs_info->policy_dbs : NULL;
276}
277
278static void cs_free(struct policy_dbs_info *policy_dbs)
279{
280 kfree(to_dbs_info(policy_dbs));
281}
282
283static int cs_init(struct dbs_data *dbs_data)
284{
285 struct cs_dbs_tuners *tuners;
286
287 tuners = kzalloc(sizeof(*tuners), GFP_KERNEL);
288 if (!tuners)
289 return -ENOMEM;
290
291 tuners->down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD;
292 tuners->freq_step = DEF_FREQUENCY_STEP;
293 dbs_data->up_threshold = DEF_FREQUENCY_UP_THRESHOLD;
294 dbs_data->sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR;
295 dbs_data->ignore_nice_load = 0;
296 dbs_data->tuners = tuners;
297
298 return 0;
299}
300
301static void cs_exit(struct dbs_data *dbs_data)
302{
303 kfree(dbs_data->tuners);
304}
305
306static void cs_start(struct cpufreq_policy *policy)
307{
308 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy->governor_data);
309
310 dbs_info->down_skip = 0;
311 dbs_info->requested_freq = policy->cur;
312}
313
314static struct dbs_governor cs_governor = {
315 .gov = CPUFREQ_DBS_GOVERNOR_INITIALIZER("conservative"),
316 .kobj_type = { .default_attrs = cs_attributes },
317 .gov_dbs_update = cs_dbs_update,
318 .alloc = cs_alloc,
319 .free = cs_free,
320 .init = cs_init,
321 .exit = cs_exit,
322 .start = cs_start,
323};
324
325#define CPU_FREQ_GOV_CONSERVATIVE (cs_governor.gov)
326
327MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
328MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
329 "Low Latency Frequency Transition capable processors "
330 "optimised for use in a battery environment");
331MODULE_LICENSE("GPL");
332
333#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
334struct cpufreq_governor *cpufreq_default_governor(void)
335{
336 return &CPU_FREQ_GOV_CONSERVATIVE;
337}
338#endif
339
340cpufreq_governor_init(CPU_FREQ_GOV_CONSERVATIVE);
341cpufreq_governor_exit(CPU_FREQ_GOV_CONSERVATIVE);
1/*
2 * drivers/cpufreq/cpufreq_conservative.c
3 *
4 * Copyright (C) 2001 Russell King
5 * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
6 * Jun Nakajima <jun.nakajima@intel.com>
7 * (C) 2009 Alexander Clouter <alex@digriz.org.uk>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14#include <linux/slab.h>
15#include "cpufreq_governor.h"
16
17struct cs_policy_dbs_info {
18 struct policy_dbs_info policy_dbs;
19 unsigned int down_skip;
20 unsigned int requested_freq;
21};
22
23static inline struct cs_policy_dbs_info *to_dbs_info(struct policy_dbs_info *policy_dbs)
24{
25 return container_of(policy_dbs, struct cs_policy_dbs_info, policy_dbs);
26}
27
28struct cs_dbs_tuners {
29 unsigned int down_threshold;
30 unsigned int freq_step;
31};
32
33/* Conservative governor macros */
34#define DEF_FREQUENCY_UP_THRESHOLD (80)
35#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
36#define DEF_FREQUENCY_STEP (5)
37#define DEF_SAMPLING_DOWN_FACTOR (1)
38#define MAX_SAMPLING_DOWN_FACTOR (10)
39
40static inline unsigned int get_freq_target(struct cs_dbs_tuners *cs_tuners,
41 struct cpufreq_policy *policy)
42{
43 unsigned int freq_target = (cs_tuners->freq_step * policy->max) / 100;
44
45 /* max freq cannot be less than 100. But who knows... */
46 if (unlikely(freq_target == 0))
47 freq_target = DEF_FREQUENCY_STEP;
48
49 return freq_target;
50}
51
52/*
53 * Every sampling_rate, we check, if current idle time is less than 20%
54 * (default), then we try to increase frequency. Every sampling_rate *
55 * sampling_down_factor, we check, if current idle time is more than 80%
56 * (default), then we try to decrease frequency
57 *
58 * Any frequency increase takes it to the maximum frequency. Frequency reduction
59 * happens at minimum steps of 5% (default) of maximum frequency
60 */
61static unsigned int cs_dbs_timer(struct cpufreq_policy *policy)
62{
63 struct policy_dbs_info *policy_dbs = policy->governor_data;
64 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy_dbs);
65 struct dbs_data *dbs_data = policy_dbs->dbs_data;
66 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
67 unsigned int load = dbs_update(policy);
68
69 /*
70 * break out if we 'cannot' reduce the speed as the user might
71 * want freq_step to be zero
72 */
73 if (cs_tuners->freq_step == 0)
74 goto out;
75
76 /* Check for frequency increase */
77 if (load > dbs_data->up_threshold) {
78 dbs_info->down_skip = 0;
79
80 /* if we are already at full speed then break out early */
81 if (dbs_info->requested_freq == policy->max)
82 goto out;
83
84 dbs_info->requested_freq += get_freq_target(cs_tuners, policy);
85
86 if (dbs_info->requested_freq > policy->max)
87 dbs_info->requested_freq = policy->max;
88
89 __cpufreq_driver_target(policy, dbs_info->requested_freq,
90 CPUFREQ_RELATION_H);
91 goto out;
92 }
93
94 /* if sampling_down_factor is active break out early */
95 if (++dbs_info->down_skip < dbs_data->sampling_down_factor)
96 goto out;
97 dbs_info->down_skip = 0;
98
99 /* Check for frequency decrease */
100 if (load < cs_tuners->down_threshold) {
101 unsigned int freq_target;
102 /*
103 * if we cannot reduce the frequency anymore, break out early
104 */
105 if (policy->cur == policy->min)
106 goto out;
107
108 freq_target = get_freq_target(cs_tuners, policy);
109 if (dbs_info->requested_freq > freq_target)
110 dbs_info->requested_freq -= freq_target;
111 else
112 dbs_info->requested_freq = policy->min;
113
114 __cpufreq_driver_target(policy, dbs_info->requested_freq,
115 CPUFREQ_RELATION_L);
116 }
117
118 out:
119 return dbs_data->sampling_rate;
120}
121
122static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
123 void *data);
124
125static struct notifier_block cs_cpufreq_notifier_block = {
126 .notifier_call = dbs_cpufreq_notifier,
127};
128
129/************************** sysfs interface ************************/
130static struct dbs_governor cs_dbs_gov;
131
132static ssize_t store_sampling_down_factor(struct dbs_data *dbs_data,
133 const char *buf, size_t count)
134{
135 unsigned int input;
136 int ret;
137 ret = sscanf(buf, "%u", &input);
138
139 if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
140 return -EINVAL;
141
142 dbs_data->sampling_down_factor = input;
143 return count;
144}
145
146static ssize_t store_up_threshold(struct dbs_data *dbs_data, const char *buf,
147 size_t count)
148{
149 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
150 unsigned int input;
151 int ret;
152 ret = sscanf(buf, "%u", &input);
153
154 if (ret != 1 || input > 100 || input <= cs_tuners->down_threshold)
155 return -EINVAL;
156
157 dbs_data->up_threshold = input;
158 return count;
159}
160
161static ssize_t store_down_threshold(struct dbs_data *dbs_data, const char *buf,
162 size_t count)
163{
164 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
165 unsigned int input;
166 int ret;
167 ret = sscanf(buf, "%u", &input);
168
169 /* cannot be lower than 11 otherwise freq will not fall */
170 if (ret != 1 || input < 11 || input > 100 ||
171 input >= dbs_data->up_threshold)
172 return -EINVAL;
173
174 cs_tuners->down_threshold = input;
175 return count;
176}
177
178static ssize_t store_ignore_nice_load(struct dbs_data *dbs_data,
179 const char *buf, size_t count)
180{
181 unsigned int input;
182 int ret;
183
184 ret = sscanf(buf, "%u", &input);
185 if (ret != 1)
186 return -EINVAL;
187
188 if (input > 1)
189 input = 1;
190
191 if (input == dbs_data->ignore_nice_load) /* nothing to do */
192 return count;
193
194 dbs_data->ignore_nice_load = input;
195
196 /* we need to re-evaluate prev_cpu_idle */
197 gov_update_cpu_data(dbs_data);
198
199 return count;
200}
201
202static ssize_t store_freq_step(struct dbs_data *dbs_data, const char *buf,
203 size_t count)
204{
205 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
206 unsigned int input;
207 int ret;
208 ret = sscanf(buf, "%u", &input);
209
210 if (ret != 1)
211 return -EINVAL;
212
213 if (input > 100)
214 input = 100;
215
216 /*
217 * no need to test here if freq_step is zero as the user might actually
218 * want this, they would be crazy though :)
219 */
220 cs_tuners->freq_step = input;
221 return count;
222}
223
224gov_show_one_common(sampling_rate);
225gov_show_one_common(sampling_down_factor);
226gov_show_one_common(up_threshold);
227gov_show_one_common(ignore_nice_load);
228gov_show_one_common(min_sampling_rate);
229gov_show_one(cs, down_threshold);
230gov_show_one(cs, freq_step);
231
232gov_attr_rw(sampling_rate);
233gov_attr_rw(sampling_down_factor);
234gov_attr_rw(up_threshold);
235gov_attr_rw(ignore_nice_load);
236gov_attr_ro(min_sampling_rate);
237gov_attr_rw(down_threshold);
238gov_attr_rw(freq_step);
239
240static struct attribute *cs_attributes[] = {
241 &min_sampling_rate.attr,
242 &sampling_rate.attr,
243 &sampling_down_factor.attr,
244 &up_threshold.attr,
245 &down_threshold.attr,
246 &ignore_nice_load.attr,
247 &freq_step.attr,
248 NULL
249};
250
251/************************** sysfs end ************************/
252
253static struct policy_dbs_info *cs_alloc(void)
254{
255 struct cs_policy_dbs_info *dbs_info;
256
257 dbs_info = kzalloc(sizeof(*dbs_info), GFP_KERNEL);
258 return dbs_info ? &dbs_info->policy_dbs : NULL;
259}
260
261static void cs_free(struct policy_dbs_info *policy_dbs)
262{
263 kfree(to_dbs_info(policy_dbs));
264}
265
266static int cs_init(struct dbs_data *dbs_data, bool notify)
267{
268 struct cs_dbs_tuners *tuners;
269
270 tuners = kzalloc(sizeof(*tuners), GFP_KERNEL);
271 if (!tuners) {
272 pr_err("%s: kzalloc failed\n", __func__);
273 return -ENOMEM;
274 }
275
276 tuners->down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD;
277 tuners->freq_step = DEF_FREQUENCY_STEP;
278 dbs_data->up_threshold = DEF_FREQUENCY_UP_THRESHOLD;
279 dbs_data->sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR;
280 dbs_data->ignore_nice_load = 0;
281
282 dbs_data->tuners = tuners;
283 dbs_data->min_sampling_rate = MIN_SAMPLING_RATE_RATIO *
284 jiffies_to_usecs(10);
285
286 if (notify)
287 cpufreq_register_notifier(&cs_cpufreq_notifier_block,
288 CPUFREQ_TRANSITION_NOTIFIER);
289
290 return 0;
291}
292
293static void cs_exit(struct dbs_data *dbs_data, bool notify)
294{
295 if (notify)
296 cpufreq_unregister_notifier(&cs_cpufreq_notifier_block,
297 CPUFREQ_TRANSITION_NOTIFIER);
298
299 kfree(dbs_data->tuners);
300}
301
302static void cs_start(struct cpufreq_policy *policy)
303{
304 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy->governor_data);
305
306 dbs_info->down_skip = 0;
307 dbs_info->requested_freq = policy->cur;
308}
309
310static struct dbs_governor cs_dbs_gov = {
311 .gov = {
312 .name = "conservative",
313 .governor = cpufreq_governor_dbs,
314 .max_transition_latency = TRANSITION_LATENCY_LIMIT,
315 .owner = THIS_MODULE,
316 },
317 .kobj_type = { .default_attrs = cs_attributes },
318 .gov_dbs_timer = cs_dbs_timer,
319 .alloc = cs_alloc,
320 .free = cs_free,
321 .init = cs_init,
322 .exit = cs_exit,
323 .start = cs_start,
324};
325
326#define CPU_FREQ_GOV_CONSERVATIVE (&cs_dbs_gov.gov)
327
328static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
329 void *data)
330{
331 struct cpufreq_freqs *freq = data;
332 struct cpufreq_policy *policy = cpufreq_cpu_get_raw(freq->cpu);
333 struct cs_policy_dbs_info *dbs_info;
334
335 if (!policy)
336 return 0;
337
338 /* policy isn't governed by conservative governor */
339 if (policy->governor != CPU_FREQ_GOV_CONSERVATIVE)
340 return 0;
341
342 dbs_info = to_dbs_info(policy->governor_data);
343 /*
344 * we only care if our internally tracked freq moves outside the 'valid'
345 * ranges of frequency available to us otherwise we do not change it
346 */
347 if (dbs_info->requested_freq > policy->max
348 || dbs_info->requested_freq < policy->min)
349 dbs_info->requested_freq = freq->new;
350
351 return 0;
352}
353
354static int __init cpufreq_gov_dbs_init(void)
355{
356 return cpufreq_register_governor(CPU_FREQ_GOV_CONSERVATIVE);
357}
358
359static void __exit cpufreq_gov_dbs_exit(void)
360{
361 cpufreq_unregister_governor(CPU_FREQ_GOV_CONSERVATIVE);
362}
363
364MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
365MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
366 "Low Latency Frequency Transition capable processors "
367 "optimised for use in a battery environment");
368MODULE_LICENSE("GPL");
369
370#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
371struct cpufreq_governor *cpufreq_default_governor(void)
372{
373 return CPU_FREQ_GOV_CONSERVATIVE;
374}
375
376fs_initcall(cpufreq_gov_dbs_init);
377#else
378module_init(cpufreq_gov_dbs_init);
379#endif
380module_exit(cpufreq_gov_dbs_exit);