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-rw-r--r--drivers/cpufreq/cpufreq_conservative.c121
1 files changed, 60 insertions, 61 deletions
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 57d02e990af3..1bba99747f5b 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -37,17 +37,17 @@
37#define DEF_FREQUENCY_UP_THRESHOLD (80) 37#define DEF_FREQUENCY_UP_THRESHOLD (80)
38#define DEF_FREQUENCY_DOWN_THRESHOLD (20) 38#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
39 39
40/* 40/*
41 * The polling frequency of this governor depends on the capability of 41 * The polling frequency of this governor depends on the capability of
42 * the processor. Default polling frequency is 1000 times the transition 42 * the processor. Default polling frequency is 1000 times the transition
43 * latency of the processor. The governor will work on any processor with 43 * latency of the processor. The governor will work on any processor with
44 * transition latency <= 10mS, using appropriate sampling 44 * transition latency <= 10mS, using appropriate sampling
45 * rate. 45 * rate.
46 * For CPUs with transition latency > 10mS (mostly drivers 46 * For CPUs with transition latency > 10mS (mostly drivers
47 * with CPUFREQ_ETERNAL), this governor will not work. 47 * with CPUFREQ_ETERNAL), this governor will not work.
48 * All times here are in uS. 48 * All times here are in uS.
49 */ 49 */
50static unsigned int def_sampling_rate; 50static unsigned int def_sampling_rate;
51#define MIN_SAMPLING_RATE_RATIO (2) 51#define MIN_SAMPLING_RATE_RATIO (2)
52/* for correct statistics, we need at least 10 ticks between each measure */ 52/* for correct statistics, we need at least 10 ticks between each measure */
53#define MIN_STAT_SAMPLING_RATE \ 53#define MIN_STAT_SAMPLING_RATE \
@@ -63,12 +63,12 @@ static unsigned int def_sampling_rate;
63static void do_dbs_timer(struct work_struct *work); 63static void do_dbs_timer(struct work_struct *work);
64 64
65struct cpu_dbs_info_s { 65struct cpu_dbs_info_s {
66 struct cpufreq_policy *cur_policy; 66 struct cpufreq_policy *cur_policy;
67 unsigned int prev_cpu_idle_up; 67 unsigned int prev_cpu_idle_up;
68 unsigned int prev_cpu_idle_down; 68 unsigned int prev_cpu_idle_down;
69 unsigned int enable; 69 unsigned int enable;
70 unsigned int down_skip; 70 unsigned int down_skip;
71 unsigned int requested_freq; 71 unsigned int requested_freq;
72}; 72};
73static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info); 73static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
74 74
@@ -82,24 +82,24 @@ static unsigned int dbs_enable; /* number of CPUs using this policy */
82 * cpu_hotplug lock should be taken before that. Note that cpu_hotplug lock 82 * cpu_hotplug lock should be taken before that. Note that cpu_hotplug lock
83 * is recursive for the same process. -Venki 83 * is recursive for the same process. -Venki
84 */ 84 */
85static DEFINE_MUTEX (dbs_mutex); 85static DEFINE_MUTEX (dbs_mutex);
86static DECLARE_DELAYED_WORK(dbs_work, do_dbs_timer); 86static DECLARE_DELAYED_WORK(dbs_work, do_dbs_timer);
87 87
88struct dbs_tuners { 88struct dbs_tuners {
89 unsigned int sampling_rate; 89 unsigned int sampling_rate;
90 unsigned int sampling_down_factor; 90 unsigned int sampling_down_factor;
91 unsigned int up_threshold; 91 unsigned int up_threshold;
92 unsigned int down_threshold; 92 unsigned int down_threshold;
93 unsigned int ignore_nice; 93 unsigned int ignore_nice;
94 unsigned int freq_step; 94 unsigned int freq_step;
95}; 95};
96 96
97static struct dbs_tuners dbs_tuners_ins = { 97static struct dbs_tuners dbs_tuners_ins = {
98 .up_threshold = DEF_FREQUENCY_UP_THRESHOLD, 98 .up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
99 .down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD, 99 .down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
100 .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR, 100 .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
101 .ignore_nice = 0, 101 .ignore_nice = 0,
102 .freq_step = 5, 102 .freq_step = 5,
103}; 103};
104 104
105static inline unsigned int get_cpu_idle_time(unsigned int cpu) 105static inline unsigned int get_cpu_idle_time(unsigned int cpu)
@@ -109,7 +109,7 @@ static inline unsigned int get_cpu_idle_time(unsigned int cpu)
109 if (dbs_tuners_ins.ignore_nice) 109 if (dbs_tuners_ins.ignore_nice)
110 add_nice = kstat_cpu(cpu).cpustat.nice; 110 add_nice = kstat_cpu(cpu).cpustat.nice;
111 111
112 ret = kstat_cpu(cpu).cpustat.idle + 112 ret = kstat_cpu(cpu).cpustat.idle +
113 kstat_cpu(cpu).cpustat.iowait + 113 kstat_cpu(cpu).cpustat.iowait +
114 add_nice; 114 add_nice;
115 115
@@ -148,8 +148,8 @@ static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf)
148 return sprintf (buf, "%u\n", MIN_SAMPLING_RATE); 148 return sprintf (buf, "%u\n", MIN_SAMPLING_RATE);
149} 149}
150 150
151#define define_one_ro(_name) \ 151#define define_one_ro(_name) \
152static struct freq_attr _name = \ 152static struct freq_attr _name = \
153__ATTR(_name, 0444, show_##_name, NULL) 153__ATTR(_name, 0444, show_##_name, NULL)
154 154
155define_one_ro(sampling_rate_max); 155define_one_ro(sampling_rate_max);
@@ -169,7 +169,7 @@ show_one(down_threshold, down_threshold);
169show_one(ignore_nice_load, ignore_nice); 169show_one(ignore_nice_load, ignore_nice);
170show_one(freq_step, freq_step); 170show_one(freq_step, freq_step);
171 171
172static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused, 172static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
173 const char *buf, size_t count) 173 const char *buf, size_t count)
174{ 174{
175 unsigned int input; 175 unsigned int input;
@@ -185,7 +185,7 @@ static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
185 return count; 185 return count;
186} 186}
187 187
188static ssize_t store_sampling_rate(struct cpufreq_policy *unused, 188static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
189 const char *buf, size_t count) 189 const char *buf, size_t count)
190{ 190{
191 unsigned int input; 191 unsigned int input;
@@ -204,7 +204,7 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
204 return count; 204 return count;
205} 205}
206 206
207static ssize_t store_up_threshold(struct cpufreq_policy *unused, 207static ssize_t store_up_threshold(struct cpufreq_policy *unused,
208 const char *buf, size_t count) 208 const char *buf, size_t count)
209{ 209{
210 unsigned int input; 210 unsigned int input;
@@ -223,7 +223,7 @@ static ssize_t store_up_threshold(struct cpufreq_policy *unused,
223 return count; 223 return count;
224} 224}
225 225
226static ssize_t store_down_threshold(struct cpufreq_policy *unused, 226static ssize_t store_down_threshold(struct cpufreq_policy *unused,
227 const char *buf, size_t count) 227 const char *buf, size_t count)
228{ 228{
229 unsigned int input; 229 unsigned int input;
@@ -249,16 +249,16 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
249 int ret; 249 int ret;
250 250
251 unsigned int j; 251 unsigned int j;
252 252
253 ret = sscanf (buf, "%u", &input); 253 ret = sscanf(buf, "%u", &input);
254 if ( ret != 1 ) 254 if (ret != 1)
255 return -EINVAL; 255 return -EINVAL;
256 256
257 if ( input > 1 ) 257 if (input > 1)
258 input = 1; 258 input = 1;
259 259
260 mutex_lock(&dbs_mutex); 260 mutex_lock(&dbs_mutex);
261 if ( input == dbs_tuners_ins.ignore_nice ) { /* nothing to do */ 261 if (input == dbs_tuners_ins.ignore_nice) { /* nothing to do */
262 mutex_unlock(&dbs_mutex); 262 mutex_unlock(&dbs_mutex);
263 return count; 263 return count;
264 } 264 }
@@ -282,14 +282,14 @@ static ssize_t store_freq_step(struct cpufreq_policy *policy,
282 unsigned int input; 282 unsigned int input;
283 int ret; 283 int ret;
284 284
285 ret = sscanf (buf, "%u", &input); 285 ret = sscanf(buf, "%u", &input);
286 286
287 if ( ret != 1 ) 287 if (ret != 1)
288 return -EINVAL; 288 return -EINVAL;
289 289
290 if ( input > 100 ) 290 if (input > 100)
291 input = 100; 291 input = 100;
292 292
293 /* no need to test here if freq_step is zero as the user might actually 293 /* no need to test here if freq_step is zero as the user might actually
294 * want this, they would be crazy though :) */ 294 * want this, they would be crazy though :) */
295 mutex_lock(&dbs_mutex); 295 mutex_lock(&dbs_mutex);
@@ -343,18 +343,18 @@ static void dbs_check_cpu(int cpu)
343 343
344 policy = this_dbs_info->cur_policy; 344 policy = this_dbs_info->cur_policy;
345 345
346 /* 346 /*
347 * The default safe range is 20% to 80% 347 * The default safe range is 20% to 80%
348 * Every sampling_rate, we check 348 * Every sampling_rate, we check
349 * - If current idle time is less than 20%, then we try to 349 * - If current idle time is less than 20%, then we try to
350 * increase frequency 350 * increase frequency
351 * Every sampling_rate*sampling_down_factor, we check 351 * Every sampling_rate*sampling_down_factor, we check
352 * - If current idle time is more than 80%, then we try to 352 * - If current idle time is more than 80%, then we try to
353 * decrease frequency 353 * decrease frequency
354 * 354 *
355 * Any frequency increase takes it to the maximum frequency. 355 * Any frequency increase takes it to the maximum frequency.
356 * Frequency reduction happens at minimum steps of 356 * Frequency reduction happens at minimum steps of
357 * 5% (default) of max_frequency 357 * 5% (default) of max_frequency
358 */ 358 */
359 359
360 /* Check for frequency increase */ 360 /* Check for frequency increase */
@@ -382,13 +382,13 @@ static void dbs_check_cpu(int cpu)
382 /* if we are already at full speed then break out early */ 382 /* if we are already at full speed then break out early */
383 if (this_dbs_info->requested_freq == policy->max) 383 if (this_dbs_info->requested_freq == policy->max)
384 return; 384 return;
385 385
386 freq_step = (dbs_tuners_ins.freq_step * policy->max) / 100; 386 freq_step = (dbs_tuners_ins.freq_step * policy->max) / 100;
387 387
388 /* max freq cannot be less than 100. But who knows.... */ 388 /* max freq cannot be less than 100. But who knows.... */
389 if (unlikely(freq_step == 0)) 389 if (unlikely(freq_step == 0))
390 freq_step = 5; 390 freq_step = 5;
391 391
392 this_dbs_info->requested_freq += freq_step; 392 this_dbs_info->requested_freq += freq_step;
393 if (this_dbs_info->requested_freq > policy->max) 393 if (this_dbs_info->requested_freq > policy->max)
394 this_dbs_info->requested_freq = policy->max; 394 this_dbs_info->requested_freq = policy->max;
@@ -448,15 +448,15 @@ static void dbs_check_cpu(int cpu)
448} 448}
449 449
450static void do_dbs_timer(struct work_struct *work) 450static void do_dbs_timer(struct work_struct *work)
451{ 451{
452 int i; 452 int i;
453 mutex_lock(&dbs_mutex); 453 mutex_lock(&dbs_mutex);
454 for_each_online_cpu(i) 454 for_each_online_cpu(i)
455 dbs_check_cpu(i); 455 dbs_check_cpu(i);
456 schedule_delayed_work(&dbs_work, 456 schedule_delayed_work(&dbs_work,
457 usecs_to_jiffies(dbs_tuners_ins.sampling_rate)); 457 usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
458 mutex_unlock(&dbs_mutex); 458 mutex_unlock(&dbs_mutex);
459} 459}
460 460
461static inline void dbs_timer_init(void) 461static inline void dbs_timer_init(void)
462{ 462{
@@ -483,13 +483,12 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
483 483
484 switch (event) { 484 switch (event) {
485 case CPUFREQ_GOV_START: 485 case CPUFREQ_GOV_START:
486 if ((!cpu_online(cpu)) || 486 if ((!cpu_online(cpu)) || (!policy->cur))
487 (!policy->cur))
488 return -EINVAL; 487 return -EINVAL;
489 488
490 if (this_dbs_info->enable) /* Already enabled */ 489 if (this_dbs_info->enable) /* Already enabled */
491 break; 490 break;
492 491
493 mutex_lock(&dbs_mutex); 492 mutex_lock(&dbs_mutex);
494 493
495 rc = sysfs_create_group(&policy->kobj, &dbs_attr_group); 494 rc = sysfs_create_group(&policy->kobj, &dbs_attr_group);
@@ -502,7 +501,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
502 struct cpu_dbs_info_s *j_dbs_info; 501 struct cpu_dbs_info_s *j_dbs_info;
503 j_dbs_info = &per_cpu(cpu_dbs_info, j); 502 j_dbs_info = &per_cpu(cpu_dbs_info, j);
504 j_dbs_info->cur_policy = policy; 503 j_dbs_info->cur_policy = policy;
505 504
506 j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(cpu); 505 j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(cpu);
507 j_dbs_info->prev_cpu_idle_down 506 j_dbs_info->prev_cpu_idle_down
508 = j_dbs_info->prev_cpu_idle_up; 507 = j_dbs_info->prev_cpu_idle_up;
@@ -536,7 +535,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
536 &dbs_cpufreq_notifier_block, 535 &dbs_cpufreq_notifier_block,
537 CPUFREQ_TRANSITION_NOTIFIER); 536 CPUFREQ_TRANSITION_NOTIFIER);
538 } 537 }
539 538
540 mutex_unlock(&dbs_mutex); 539 mutex_unlock(&dbs_mutex);
541 break; 540 break;
542 541
@@ -565,11 +564,11 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
565 if (policy->max < this_dbs_info->cur_policy->cur) 564 if (policy->max < this_dbs_info->cur_policy->cur)
566 __cpufreq_driver_target( 565 __cpufreq_driver_target(
567 this_dbs_info->cur_policy, 566 this_dbs_info->cur_policy,
568 policy->max, CPUFREQ_RELATION_H); 567 policy->max, CPUFREQ_RELATION_H);
569 else if (policy->min > this_dbs_info->cur_policy->cur) 568 else if (policy->min > this_dbs_info->cur_policy->cur)
570 __cpufreq_driver_target( 569 __cpufreq_driver_target(
571 this_dbs_info->cur_policy, 570 this_dbs_info->cur_policy,
572 policy->min, CPUFREQ_RELATION_L); 571 policy->min, CPUFREQ_RELATION_L);
573 mutex_unlock(&dbs_mutex); 572 mutex_unlock(&dbs_mutex);
574 break; 573 break;
575 } 574 }