drivers/cpufreq/cpufreq_interactive.c

   1 /*
   2  * drivers/cpufreq/cpufreq_interactive.c
   3  *
   4  * Copyright (C) 2010 Google, Inc.
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * Author: Mike Chan (mike@android.com)
  16  *
  17  */
  18
  19 #include <linux/cpu.h>
  20 #include <linux/cpumask.h>
  21 #include <linux/cpufreq.h>
  22 #include <linux/module.h>
  23 #include <linux/moduleparam.h>
  24 #include <linux/rwsem.h>
  25 #include <linux/sched.h>
  26 #include <linux/sched/rt.h>
  27 #include <linux/tick.h>
  28 #include <linux/time.h>
  29 #include <linux/timer.h>
  30 #include <linux/workqueue.h>
  31 #include <linux/kthread.h>
  32 #include <linux/slab.h>
  33
  34 #define CREATE_TRACE_POINTS
  35 #include <trace/events/cpufreq_interactive.h>
  36
  37 struct cpufreq_interactive_cpuinfo {
  38         struct timer_list cpu_timer;
  39         struct timer_list cpu_slack_timer;
  40         spinlock_t load_lock; /* protects the next 4 fields */
  41         u64 time_in_idle;
  42         u64 time_in_idle_timestamp;
  43         u64 cputime_speedadj;
  44         u64 cputime_speedadj_timestamp;
  45         struct cpufreq_policy *policy;
  46         struct cpufreq_frequency_table *freq_table;
  47         unsigned int target_freq;
  48         unsigned int floor_freq;
  49         u64 floor_validate_time;
  50         u64 hispeed_validate_time;
  51         struct rw_semaphore enable_sem;
  52         int governor_enabled;
  53 };
  54
  55 static DEFINE_PER_CPU(struct cpufreq_interactive_cpuinfo, cpuinfo);
  56
  57 /* realtime thread handles frequency scaling */
  58 static struct task_struct *speedchange_task;
  59 static cpumask_t speedchange_cpumask;
  60 static spinlock_t speedchange_cpumask_lock;
  61 static struct mutex gov_lock;
  62
  63 /* Target load.  Lower values result in higher CPU speeds. */
  64 #define DEFAULT_TARGET_LOAD 90
  65 static unsigned int default_target_loads[] = {DEFAULT_TARGET_LOAD};
  66
  67 #define DEFAULT_TIMER_RATE (20 * USEC_PER_MSEC)
  68 #define DEFAULT_ABOVE_HISPEED_DELAY DEFAULT_TIMER_RATE
  69 static unsigned int default_above_hispeed_delay[] = {
  70         DEFAULT_ABOVE_HISPEED_DELAY };
  71
  72 struct cpufreq_interactive_tunables {
  73         int usage_count;
  74         /* Hi speed to bump to from lo speed when load burst (default max) */
  75         unsigned int hispeed_freq;
  76         /* Go to hi speed when CPU load at or above this value. */
  77 #define DEFAULT_GO_HISPEED_LOAD 99
  78         unsigned long go_hispeed_load;
  79         /* Target load. Lower values result in higher CPU speeds. */
  80         spinlock_t target_loads_lock;
  81         unsigned int *target_loads;
  82         int ntarget_loads;
  83         /*
  84          * The minimum amount of time to spend at a frequency before we can ramp
  85          * down.
  86          */
  87 #define DEFAULT_MIN_SAMPLE_TIME (80 * USEC_PER_MSEC)
  88         unsigned long min_sample_time;
  89         /*
  90          * The sample rate of the timer used to increase frequency
  91          */
  92         unsigned long timer_rate;
  93         /*
  94          * Wait this long before raising speed above hispeed, by default a
  95          * single timer interval.
  96          */
  97         spinlock_t above_hispeed_delay_lock;
  98         unsigned int *above_hispeed_delay;
  99         int nabove_hispeed_delay;
 100         /* Non-zero means indefinite speed boost active */
 101         int boost_val;
 102         /* Duration of a boot pulse in usecs */
 103         int boostpulse_duration_val;
 104         /* End time of boost pulse in ktime converted to usecs */
 105         u64 boostpulse_endtime;
 106         /*
 107          * Max additional time to wait in idle, beyond timer_rate, at speeds
 108          * above minimum before wakeup to reduce speed, or -1 if unnecessary.
 109          */
 110 #define DEFAULT_TIMER_SLACK (4 * DEFAULT_TIMER_RATE)
 111         int timer_slack_val;
 112         bool io_is_busy;
 113 };
 114
 115 /* For cases where we have single governor instance for system */
 116 struct cpufreq_interactive_tunables *common_tunables;
 117
 118 static struct attribute_group *get_sysfs_attr(void);
 119
 120 static void cpufreq_interactive_timer_resched(
 121         struct cpufreq_interactive_cpuinfo *pcpu)
 122 {
 123         struct cpufreq_interactive_tunables *tunables =
 124                 pcpu->policy->governor_data;
 125         unsigned long expires;
 126         unsigned long flags;
 127
 128         spin_lock_irqsave(&pcpu->load_lock, flags);
 129         pcpu->time_in_idle =
 130                 get_cpu_idle_time(smp_processor_id(),
 131                                   &pcpu->time_in_idle_timestamp,
 132                                   tunables->io_is_busy);
 133         pcpu->cputime_speedadj = 0;
 134         pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp;
 135         expires = jiffies + usecs_to_jiffies(tunables->timer_rate);
 136         mod_timer_pinned(&pcpu->cpu_timer, expires);
 137
 138         if (tunables->timer_slack_val >= 0 &&
 139             pcpu->target_freq > pcpu->policy->min) {
 140                 expires += usecs_to_jiffies(tunables->timer_slack_val);
 141                 mod_timer_pinned(&pcpu->cpu_slack_timer, expires);
 142         }
 143
 144         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 145 }
 146
 147 /* The caller shall take enable_sem write semaphore to avoid any timer race.
 148  * The cpu_timer and cpu_slack_timer must be deactivated when calling this
 149  * function.
 150  */
 151 static void cpufreq_interactive_timer_start(
 152         struct cpufreq_interactive_tunables *tunables, int cpu)
 153 {
 154         struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
 155         unsigned long expires = jiffies +
 156                 usecs_to_jiffies(tunables->timer_rate);
 157         unsigned long flags;
 158
 159         pcpu->cpu_timer.expires = expires;
 160         add_timer_on(&pcpu->cpu_timer, cpu);
 161         if (tunables->timer_slack_val >= 0 &&
 162             pcpu->target_freq > pcpu->policy->min) {
 163                 expires += usecs_to_jiffies(tunables->timer_slack_val);
 164                 pcpu->cpu_slack_timer.expires = expires;
 165                 add_timer_on(&pcpu->cpu_slack_timer, cpu);
 166         }
 167
 168         spin_lock_irqsave(&pcpu->load_lock, flags);
 169         pcpu->time_in_idle =
 170                 get_cpu_idle_time(cpu, &pcpu->time_in_idle_timestamp,
 171                                   tunables->io_is_busy);
 172         pcpu->cputime_speedadj = 0;
 173         pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp;
 174         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 175 }
 176
 177 static unsigned int freq_to_above_hispeed_delay(
 178         struct cpufreq_interactive_tunables *tunables,
 179         unsigned int freq)
 180 {
 181         int i;
 182         unsigned int ret;
 183         unsigned long flags;
 184
 185         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 186
 187         for (i = 0; i < tunables->nabove_hispeed_delay - 1 &&
 188                         freq >= tunables->above_hispeed_delay[i+1]; i += 2)
 189                 ;
 190
 191         ret = tunables->above_hispeed_delay[i];
 192         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 193         return ret;
 194 }
 195
 196 static unsigned int freq_to_targetload(
 197         struct cpufreq_interactive_tunables *tunables, unsigned int freq)
 198 {
 199         int i;
 200         unsigned int ret;
 201         unsigned long flags;
 202
 203         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 204
 205         for (i = 0; i < tunables->ntarget_loads - 1 &&
 206                     freq >= tunables->target_loads[i+1]; i += 2)
 207                 ;
 208
 209         ret = tunables->target_loads[i];
 210         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 211         return ret;
 212 }
 213
 214 /*
 215  * If increasing frequencies never map to a lower target load then
 216  * choose_freq() will find the minimum frequency that does not exceed its
 217  * target load given the current load.
 218  */
 219 static unsigned int choose_freq(struct cpufreq_interactive_cpuinfo *pcpu,
 220                 unsigned int loadadjfreq)
 221 {
 222         unsigned int freq = pcpu->policy->cur;
 223         unsigned int prevfreq, freqmin, freqmax;
 224         unsigned int tl;
 225         int index;
 226
 227         freqmin = 0;
 228         freqmax = UINT_MAX;
 229
 230         do {
 231                 prevfreq = freq;
 232                 tl = freq_to_targetload(pcpu->policy->governor_data, freq);
 233
 234                 /*
 235                  * Find the lowest frequency where the computed load is less
 236                  * than or equal to the target load.
 237                  */
 238
 239                 if (cpufreq_frequency_table_target(
 240                             pcpu->policy, pcpu->freq_table, loadadjfreq / tl,
 241                             CPUFREQ_RELATION_L, &index))
 242                         break;
 243                 freq = pcpu->freq_table[index].frequency;
 244
 245                 if (freq > prevfreq) {
 246                         /* The previous frequency is too low. */
 247                         freqmin = prevfreq;
 248
 249                         if (freq >= freqmax) {
 250                                 /*
 251                                  * Find the highest frequency that is less
 252                                  * than freqmax.
 253                                  */
 254                                 if (cpufreq_frequency_table_target(
 255                                             pcpu->policy, pcpu->freq_table,
 256                                             freqmax - 1, CPUFREQ_RELATION_H,
 257                                             &index))
 258                                         break;
 259                                 freq = pcpu->freq_table[index].frequency;
 260
 261                                 if (freq == freqmin) {
 262                                         /*
 263                                          * The first frequency below freqmax
 264                                          * has already been found to be too
 265                                          * low.  freqmax is the lowest speed
 266                                          * we found that is fast enough.
 267                                          */
 268                                         freq = freqmax;
 269                                         break;
 270                                 }
 271                         }
 272                 } else if (freq < prevfreq) {
 273                         /* The previous frequency is high enough. */
 274                         freqmax = prevfreq;
 275
 276                         if (freq <= freqmin) {
 277                                 /*
 278                                  * Find the lowest frequency that is higher
 279                                  * than freqmin.
 280                                  */
 281                                 if (cpufreq_frequency_table_target(
 282                                             pcpu->policy, pcpu->freq_table,
 283                                             freqmin + 1, CPUFREQ_RELATION_L,
 284                                             &index))
 285                                         break;
 286                                 freq = pcpu->freq_table[index].frequency;
 287
 288                                 /*
 289                                  * If freqmax is the first frequency above
 290                                  * freqmin then we have already found that
 291                                  * this speed is fast enough.
 292                                  */
 293                                 if (freq == freqmax)
 294                                         break;
 295                         }
 296                 }
 297
 298                 /* If same frequency chosen as previous then done. */
 299         } while (freq != prevfreq);
 300
 301         return freq;
 302 }
 303
 304 static u64 update_load(int cpu)
 305 {
 306         struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
 307         struct cpufreq_interactive_tunables *tunables =
 308                 pcpu->policy->governor_data;
 309         u64 now;
 310         u64 now_idle;
 311         unsigned int delta_idle;
 312         unsigned int delta_time;
 313         u64 active_time;
 314
 315         now_idle = get_cpu_idle_time(cpu, &now, tunables->io_is_busy);
 316         delta_idle = (unsigned int)(now_idle - pcpu->time_in_idle);
 317         delta_time = (unsigned int)(now - pcpu->time_in_idle_timestamp);
 318
 319         if (delta_time <= delta_idle)
 320                 active_time = 0;
 321         else
 322                 active_time = delta_time - delta_idle;
 323
 324         pcpu->cputime_speedadj += active_time * pcpu->policy->cur;
 325
 326         pcpu->time_in_idle = now_idle;
 327         pcpu->time_in_idle_timestamp = now;
 328         return now;
 329 }
 330
 331 static void cpufreq_interactive_timer(unsigned long data)
 332 {
 333         u64 now;
 334         unsigned int delta_time;
 335         u64 cputime_speedadj;
 336         int cpu_load;
 337         struct cpufreq_interactive_cpuinfo *pcpu =
 338                 &per_cpu(cpuinfo, data);
 339         struct cpufreq_interactive_tunables *tunables =
 340                 pcpu->policy->governor_data;
 341         unsigned int new_freq;
 342         unsigned int loadadjfreq;
 343         unsigned int index;
 344         unsigned long flags;
 345         bool boosted;
 346
 347         if (!down_read_trylock(&pcpu->enable_sem))
 348                 return;
 349         if (!pcpu->governor_enabled)
 350                 goto exit;
 351
 352         spin_lock_irqsave(&pcpu->load_lock, flags);
 353         now = update_load(data);
 354         delta_time = (unsigned int)(now - pcpu->cputime_speedadj_timestamp);
 355         cputime_speedadj = pcpu->cputime_speedadj;
 356         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 357
 358         if (WARN_ON_ONCE(!delta_time))
 359                 goto rearm;
 360
 361         do_div(cputime_speedadj, delta_time);
 362         loadadjfreq = (unsigned int)cputime_speedadj * 100;
 363         cpu_load = loadadjfreq / pcpu->target_freq;
 364         boosted = tunables->boost_val || now < tunables->boostpulse_endtime;
 365
 366         if (cpu_load >= tunables->go_hispeed_load || boosted) {
 367                 if (pcpu->target_freq < tunables->hispeed_freq) {
 368                         new_freq = tunables->hispeed_freq;
 369                 } else {
 370                         new_freq = choose_freq(pcpu, loadadjfreq);
 371
 372                         if (new_freq < tunables->hispeed_freq)
 373                                 new_freq = tunables->hispeed_freq;
 374                 }
 375         } else {
 376                 new_freq = choose_freq(pcpu, loadadjfreq);
 377         }
 378
 379         if (pcpu->target_freq >= tunables->hispeed_freq &&
 380             new_freq > pcpu->target_freq &&
 381             now - pcpu->hispeed_validate_time <
 382             freq_to_above_hispeed_delay(tunables, pcpu->target_freq)) {
 383                 trace_cpufreq_interactive_notyet(
 384                         data, cpu_load, pcpu->target_freq,
 385                         pcpu->policy->cur, new_freq);
 386                 goto rearm;
 387         }
 388
 389         pcpu->hispeed_validate_time = now;
 390
 391         if (cpufreq_frequency_table_target(pcpu->policy, pcpu->freq_table,
 392                                            new_freq, CPUFREQ_RELATION_L,
 393                                            &index))
 394                 goto rearm;
 395
 396         new_freq = pcpu->freq_table[index].frequency;
 397
 398         /*
 399          * Do not scale below floor_freq unless we have been at or above the
 400          * floor frequency for the minimum sample time since last validated.
 401          */
 402         if (new_freq < pcpu->floor_freq) {
 403                 if (now - pcpu->floor_validate_time <
 404                                 tunables->min_sample_time) {
 405                         trace_cpufreq_interactive_notyet(
 406                                 data, cpu_load, pcpu->target_freq,
 407                                 pcpu->policy->cur, new_freq);
 408                         goto rearm;
 409                 }
 410         }
 411
 412         /*
 413          * Update the timestamp for checking whether speed has been held at
 414          * or above the selected frequency for a minimum of min_sample_time,
 415          * if not boosted to hispeed_freq.  If boosted to hispeed_freq then we
 416          * allow the speed to drop as soon as the boostpulse duration expires
 417          * (or the indefinite boost is turned off).
 418          */
 419
 420         if (!boosted || new_freq > tunables->hispeed_freq) {
 421                 pcpu->floor_freq = new_freq;
 422                 pcpu->floor_validate_time = now;
 423         }
 424
 425         if (pcpu->target_freq == new_freq) {
 426                 trace_cpufreq_interactive_already(
 427                         data, cpu_load, pcpu->target_freq,
 428                         pcpu->policy->cur, new_freq);
 429                 goto rearm_if_notmax;
 430         }
 431
 432         trace_cpufreq_interactive_target(data, cpu_load, pcpu->target_freq,
 433                                          pcpu->policy->cur, new_freq);
 434
 435         pcpu->target_freq = new_freq;
 436         spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 437         cpumask_set_cpu(data, &speedchange_cpumask);
 438         spin_unlock_irqrestore(&speedchange_cpumask_lock, flags);
 439         wake_up_process(speedchange_task);
 440
 441 rearm_if_notmax:
 442         /*
 443          * Already set max speed and don't see a need to change that,
 444          * wait until next idle to re-evaluate, don't need timer.
 445          */
 446         if (pcpu->target_freq == pcpu->policy->max)
 447                 goto exit;
 448
 449 rearm:
 450         if (!timer_pending(&pcpu->cpu_timer))
 451                 cpufreq_interactive_timer_resched(pcpu);
 452
 453 exit:
 454         up_read(&pcpu->enable_sem);
 455         return;
 456 }
 457
 458 static void cpufreq_interactive_idle_start(void)
 459 {
 460         struct cpufreq_interactive_cpuinfo *pcpu =
 461                 &per_cpu(cpuinfo, smp_processor_id());
 462         int pending;
 463
 464         if (!down_read_trylock(&pcpu->enable_sem))
 465                 return;
 466         if (!pcpu->governor_enabled) {
 467                 up_read(&pcpu->enable_sem);
 468                 return;
 469         }
 470
 471         pending = timer_pending(&pcpu->cpu_timer);
 472
 473         if (pcpu->target_freq != pcpu->policy->min) {
 474                 /*
 475                  * Entering idle while not at lowest speed.  On some
 476                  * platforms this can hold the other CPU(s) at that speed
 477                  * even though the CPU is idle. Set a timer to re-evaluate
 478                  * speed so this idle CPU doesn't hold the other CPUs above
 479                  * min indefinitely.  This should probably be a quirk of
 480                  * the CPUFreq driver.
 481                  */
 482                 if (!pending)
 483                         cpufreq_interactive_timer_resched(pcpu);
 484         }
 485
 486         up_read(&pcpu->enable_sem);
 487 }
 488
 489 static void cpufreq_interactive_idle_end(void)
 490 {
 491         struct cpufreq_interactive_cpuinfo *pcpu =
 492                 &per_cpu(cpuinfo, smp_processor_id());
 493
 494         if (!down_read_trylock(&pcpu->enable_sem))
 495                 return;
 496         if (!pcpu->governor_enabled) {
 497                 up_read(&pcpu->enable_sem);
 498                 return;
 499         }
 500
 501         /* Arm the timer for 1-2 ticks later if not already. */
 502         if (!timer_pending(&pcpu->cpu_timer)) {
 503                 cpufreq_interactive_timer_resched(pcpu);
 504         } else if (time_after_eq(jiffies, pcpu->cpu_timer.expires)) {
 505                 del_timer(&pcpu->cpu_timer);
 506                 del_timer(&pcpu->cpu_slack_timer);
 507                 cpufreq_interactive_timer(smp_processor_id());
 508         }
 509
 510         up_read(&pcpu->enable_sem);
 511 }
 512
 513 static int cpufreq_interactive_speedchange_task(void *data)
 514 {
 515         unsigned int cpu;
 516         cpumask_t tmp_mask;
 517         unsigned long flags;
 518         struct cpufreq_interactive_cpuinfo *pcpu;
 519
 520         while (1) {
 521                 set_current_state(TASK_INTERRUPTIBLE);
 522                 spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 523
 524                 if (cpumask_empty(&speedchange_cpumask)) {
 525                         spin_unlock_irqrestore(&speedchange_cpumask_lock,
 526                                                flags);
 527                         schedule();
 528
 529                         if (kthread_should_stop())
 530                                 break;
 531
 532                         spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 533                 }
 534
 535                 set_current_state(TASK_RUNNING);
 536                 tmp_mask = speedchange_cpumask;
 537                 cpumask_clear(&speedchange_cpumask);
 538                 spin_unlock_irqrestore(&speedchange_cpumask_lock, flags);
 539
 540                 for_each_cpu(cpu, &tmp_mask) {
 541                         unsigned int j;
 542                         unsigned int max_freq = 0;
 543
 544                         pcpu = &per_cpu(cpuinfo, cpu);
 545                         if (!down_read_trylock(&pcpu->enable_sem))
 546                                 continue;
 547                         if (!pcpu->governor_enabled) {
 548                                 up_read(&pcpu->enable_sem);
 549                                 continue;
 550                         }
 551
 552                         for_each_cpu(j, pcpu->policy->cpus) {
 553                                 struct cpufreq_interactive_cpuinfo *pjcpu =
 554                                         &per_cpu(cpuinfo, j);
 555
 556                                 if (pjcpu->target_freq > max_freq)
 557                                         max_freq = pjcpu->target_freq;
 558                         }
 559
 560                         if (max_freq != pcpu->policy->cur)
 561                                 __cpufreq_driver_target(pcpu->policy,
 562                                                         max_freq,
 563                                                         CPUFREQ_RELATION_H);
 564                         trace_cpufreq_interactive_setspeed(cpu,
 565                                                      pcpu->target_freq,
 566                                                      pcpu->policy->cur);
 567
 568                         up_read(&pcpu->enable_sem);
 569                 }
 570         }
 571
 572         return 0;
 573 }
 574
 575 static void cpufreq_interactive_boost(void)
 576 {
 577         int i;
 578         int anyboost = 0;
 579         unsigned long flags;
 580         struct cpufreq_interactive_cpuinfo *pcpu;
 581         struct cpufreq_interactive_tunables *tunables;
 582
 583         spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 584
 585         for_each_online_cpu(i) {
 586                 pcpu = &per_cpu(cpuinfo, i);
 587                 tunables = pcpu->policy->governor_data;
 588
 589                 if (pcpu->target_freq < tunables->hispeed_freq) {
 590                         pcpu->target_freq = tunables->hispeed_freq;
 591                         cpumask_set_cpu(i, &speedchange_cpumask);
 592                         pcpu->hispeed_validate_time =
 593                                 ktime_to_us(ktime_get());
 594                         anyboost = 1;
 595                 }
 596
 597                 /*
 598                  * Set floor freq and (re)start timer for when last
 599                  * validated.
 600                  */
 601
 602                 pcpu->floor_freq = tunables->hispeed_freq;
 603                 pcpu->floor_validate_time = ktime_to_us(ktime_get());
 604         }
 605
 606         spin_unlock_irqrestore(&speedchange_cpumask_lock, flags);
 607
 608         if (anyboost)
 609                 wake_up_process(speedchange_task);
 610 }
 611
 612 static int cpufreq_interactive_notifier(
 613         struct notifier_block *nb, unsigned long val, void *data)
 614 {
 615         struct cpufreq_freqs *freq = data;
 616         struct cpufreq_interactive_cpuinfo *pcpu;
 617         int cpu;
 618         unsigned long flags;
 619
 620         if (val == CPUFREQ_POSTCHANGE) {
 621                 pcpu = &per_cpu(cpuinfo, freq->cpu);
 622                 if (!down_read_trylock(&pcpu->enable_sem))
 623                         return 0;
 624                 if (!pcpu->governor_enabled) {
 625                         up_read(&pcpu->enable_sem);
 626                         return 0;
 627                 }
 628
 629                 for_each_cpu(cpu, pcpu->policy->cpus) {
 630                         struct cpufreq_interactive_cpuinfo *pjcpu =
 631                                 &per_cpu(cpuinfo, cpu);
 632                         if (cpu != freq->cpu) {
 633                                 if (!down_read_trylock(&pjcpu->enable_sem))
 634                                         continue;
 635                                 if (!pjcpu->governor_enabled) {
 636                                         up_read(&pjcpu->enable_sem);
 637                                         continue;
 638                                 }
 639                         }
 640                         spin_lock_irqsave(&pjcpu->load_lock, flags);
 641                         update_load(cpu);
 642                         spin_unlock_irqrestore(&pjcpu->load_lock, flags);
 643                         if (cpu != freq->cpu)
 644                                 up_read(&pjcpu->enable_sem);
 645                 }
 646
 647                 up_read(&pcpu->enable_sem);
 648         }
 649         return 0;
 650 }
 651
 652 static struct notifier_block cpufreq_notifier_block = {
 653         .notifier_call = cpufreq_interactive_notifier,
 654 };
 655
 656 static unsigned int *get_tokenized_data(const char *buf, int *num_tokens)
 657 {
 658         const char *cp;
 659         int i;
 660         int ntokens = 1;
 661         unsigned int *tokenized_data;
 662         int err = -EINVAL;
 663
 664         cp = buf;
 665         while ((cp = strpbrk(cp + 1, " :")))
 666                 ntokens++;
 667
 668         if (!(ntokens & 0x1))
 669                 goto err;
 670
 671         tokenized_data = kmalloc(ntokens * sizeof(unsigned int), GFP_KERNEL);
 672         if (!tokenized_data) {
 673                 err = -ENOMEM;
 674                 goto err;
 675         }
 676
 677         cp = buf;
 678         i = 0;
 679         while (i < ntokens) {
 680                 if (sscanf(cp, "%u", &tokenized_data[i++]) != 1)
 681                         goto err_kfree;
 682
 683                 cp = strpbrk(cp, " :");
 684                 if (!cp)
 685                         break;
 686                 cp++;
 687         }
 688
 689         if (i != ntokens)
 690                 goto err_kfree;
 691
 692         *num_tokens = ntokens;
 693         return tokenized_data;
 694
 695 err_kfree:
 696         kfree(tokenized_data);
 697 err:
 698         return ERR_PTR(err);
 699 }
 700
 701 static ssize_t show_target_loads(
 702         struct cpufreq_interactive_tunables *tunables,
 703         char *buf)
 704 {
 705         int i;
 706         ssize_t ret = 0;
 707         unsigned long flags;
 708
 709         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 710
 711         for (i = 0; i < tunables->ntarget_loads; i++)
 712                 ret += sprintf(buf + ret, "%u%s", tunables->target_loads[i],
 713                                i & 0x1 ? ":" : " ");
 714
 715         sprintf(buf + ret - 1, "\n");
 716         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 717         return ret;
 718 }
 719
 720 static ssize_t store_target_loads(
 721         struct cpufreq_interactive_tunables *tunables,
 722         const char *buf, size_t count)
 723 {
 724         int ntokens;
 725         unsigned int *new_target_loads = NULL;
 726         unsigned long flags;
 727
 728         new_target_loads = get_tokenized_data(buf, &ntokens);
 729         if (IS_ERR(new_target_loads))
 730                 return PTR_RET(new_target_loads);
 731
 732         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 733         if (tunables->target_loads != default_target_loads)
 734                 kfree(tunables->target_loads);
 735         tunables->target_loads = new_target_loads;
 736         tunables->ntarget_loads = ntokens;
 737         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 738         return count;
 739 }
 740
 741 static ssize_t show_above_hispeed_delay(
 742         struct cpufreq_interactive_tunables *tunables, char *buf)
 743 {
 744         int i;
 745         ssize_t ret = 0;
 746         unsigned long flags;
 747
 748         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 749
 750         for (i = 0; i < tunables->nabove_hispeed_delay; i++)
 751                 ret += sprintf(buf + ret, "%u%s",
 752                                tunables->above_hispeed_delay[i],
 753                                i & 0x1 ? ":" : " ");
 754
 755         sprintf(buf + ret - 1, "\n");
 756         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 757         return ret;
 758 }
 759
 760 static ssize_t store_above_hispeed_delay(
 761         struct cpufreq_interactive_tunables *tunables,
 762         const char *buf, size_t count)
 763 {
 764         int ntokens;
 765         unsigned int *new_above_hispeed_delay = NULL;
 766         unsigned long flags;
 767
 768         new_above_hispeed_delay = get_tokenized_data(buf, &ntokens);
 769         if (IS_ERR(new_above_hispeed_delay))
 770                 return PTR_RET(new_above_hispeed_delay);
 771
 772         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 773         if (tunables->above_hispeed_delay != default_above_hispeed_delay)
 774                 kfree(tunables->above_hispeed_delay);
 775         tunables->above_hispeed_delay = new_above_hispeed_delay;
 776         tunables->nabove_hispeed_delay = ntokens;
 777         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 778         return count;
 779
 780 }
 781
 782 static ssize_t show_hispeed_freq(struct cpufreq_interactive_tunables *tunables,
 783                 char *buf)
 784 {
 785         return sprintf(buf, "%u\n", tunables->hispeed_freq);
 786 }
 787
 788 static ssize_t store_hispeed_freq(struct cpufreq_interactive_tunables *tunables,
 789                 const char *buf, size_t count)
 790 {
 791         int ret;
 792         long unsigned int val;
 793
 794         ret = strict_strtoul(buf, 0, &val);
 795         if (ret < 0)
 796                 return ret;
 797         tunables->hispeed_freq = val;
 798         return count;
 799 }
 800
 801 static ssize_t show_go_hispeed_load(struct cpufreq_interactive_tunables
 802                 *tunables, char *buf)
 803 {
 804         return sprintf(buf, "%lu\n", tunables->go_hispeed_load);
 805 }
 806
 807 static ssize_t store_go_hispeed_load(struct cpufreq_interactive_tunables
 808                 *tunables, const char *buf, size_t count)
 809 {
 810         int ret;
 811         unsigned long val;
 812
 813         ret = strict_strtoul(buf, 0, &val);
 814         if (ret < 0)
 815                 return ret;
 816         tunables->go_hispeed_load = val;
 817         return count;
 818 }
 819
 820 static ssize_t show_min_sample_time(struct cpufreq_interactive_tunables
 821                 *tunables, char *buf)
 822 {
 823         return sprintf(buf, "%lu\n", tunables->min_sample_time);
 824 }
 825
 826 static ssize_t store_min_sample_time(struct cpufreq_interactive_tunables
 827                 *tunables, const char *buf, size_t count)
 828 {
 829         int ret;
 830         unsigned long val;
 831
 832         ret = strict_strtoul(buf, 0, &val);
 833         if (ret < 0)
 834                 return ret;
 835         tunables->min_sample_time = val;
 836         return count;
 837 }
 838
 839 static ssize_t show_timer_rate(struct cpufreq_interactive_tunables *tunables,
 840                 char *buf)
 841 {
 842         return sprintf(buf, "%lu\n", tunables->timer_rate);
 843 }
 844
 845 static ssize_t store_timer_rate(struct cpufreq_interactive_tunables *tunables,
 846                 const char *buf, size_t count)
 847 {
 848         int ret;
 849         unsigned long val;
 850
 851         ret = strict_strtoul(buf, 0, &val);
 852         if (ret < 0)
 853                 return ret;
 854         tunables->timer_rate = val;
 855         return count;
 856 }
 857
 858 static ssize_t show_timer_slack(struct cpufreq_interactive_tunables *tunables,
 859                 char *buf)
 860 {
 861         return sprintf(buf, "%d\n", tunables->timer_slack_val);
 862 }
 863
 864 static ssize_t store_timer_slack(struct cpufreq_interactive_tunables *tunables,
 865                 const char *buf, size_t count)
 866 {
 867         int ret;
 868         unsigned long val;
 869
 870         ret = kstrtol(buf, 10, &val);
 871         if (ret < 0)
 872                 return ret;
 873
 874         tunables->timer_slack_val = val;
 875         return count;
 876 }
 877
 878 static ssize_t show_boost(struct cpufreq_interactive_tunables *tunables,
 879                           char *buf)
 880 {
 881         return sprintf(buf, "%d\n", tunables->boost_val);
 882 }
 883
 884 static ssize_t store_boost(struct cpufreq_interactive_tunables *tunables,
 885                            const char *buf, size_t count)
 886 {
 887         int ret;
 888         unsigned long val;
 889
 890         ret = kstrtoul(buf, 0, &val);
 891         if (ret < 0)
 892                 return ret;
 893
 894         tunables->boost_val = val;
 895
 896         if (tunables->boost_val) {
 897                 trace_cpufreq_interactive_boost("on");
 898                 cpufreq_interactive_boost();
 899         } else {
 900                 trace_cpufreq_interactive_unboost("off");
 901         }
 902
 903         return count;
 904 }
 905
 906 static ssize_t store_boostpulse(struct cpufreq_interactive_tunables *tunables,
 907                                 const char *buf, size_t count)
 908 {
 909         int ret;
 910         unsigned long val;
 911
 912         ret = kstrtoul(buf, 0, &val);
 913         if (ret < 0)
 914                 return ret;
 915
 916         tunables->boostpulse_endtime = ktime_to_us(ktime_get()) +
 917                 tunables->boostpulse_duration_val;
 918         trace_cpufreq_interactive_boost("pulse");
 919         cpufreq_interactive_boost();
 920         return count;
 921 }
 922
 923 static ssize_t show_boostpulse_duration(struct cpufreq_interactive_tunables
 924                 *tunables, char *buf)
 925 {
 926         return sprintf(buf, "%d\n", tunables->boostpulse_duration_val);
 927 }
 928
 929 static ssize_t store_boostpulse_duration(struct cpufreq_interactive_tunables
 930                 *tunables, const char *buf, size_t count)
 931 {
 932         int ret;
 933         unsigned long val;
 934
 935         ret = kstrtoul(buf, 0, &val);
 936         if (ret < 0)
 937                 return ret;
 938
 939         tunables->boostpulse_duration_val = val;
 940         return count;
 941 }
 942
 943 static ssize_t show_io_is_busy(struct cpufreq_interactive_tunables *tunables,
 944                 char *buf)
 945 {
 946         return sprintf(buf, "%u\n", tunables->io_is_busy);
 947 }
 948
 949 static ssize_t store_io_is_busy(struct cpufreq_interactive_tunables *tunables,
 950                 const char *buf, size_t count)
 951 {
 952         int ret;
 953         unsigned long val;
 954
 955         ret = kstrtoul(buf, 0, &val);
 956         if (ret < 0)
 957                 return ret;
 958         tunables->io_is_busy = val;
 959         return count;
 960 }
 961
 962 /*
 963  * Create show/store routines
 964  * - sys: One governor instance for complete SYSTEM
 965  * - pol: One governor instance per struct cpufreq_policy
 966  */
 967 #define show_gov_pol_sys(file_name)                                     \
 968 static ssize_t show_##file_name##_gov_sys                               \
 969 (struct kobject *kobj, struct attribute *attr, char *buf)               \
 970 {                                                                       \
 971         return show_##file_name(common_tunables, buf);                  \
 972 }                                                                       \
 973                                                                         \
 974 static ssize_t show_##file_name##_gov_pol                               \
 975 (struct cpufreq_policy *policy, char *buf)                              \
 976 {                                                                       \
 977         return show_##file_name(policy->governor_data, buf);            \
 978 }
 979
 980 #define store_gov_pol_sys(file_name)                                    \
 981 static ssize_t store_##file_name##_gov_sys                              \
 982 (struct kobject *kobj, struct attribute *attr, const char *buf,         \
 983         size_t count)                                                   \
 984 {                                                                       \
 985         return store_##file_name(common_tunables, buf, count);          \
 986 }                                                                       \
 987                                                                         \
 988 static ssize_t store_##file_name##_gov_pol                              \
 989 (struct cpufreq_policy *policy, const char *buf, size_t count)          \
 990 {                                                                       \
 991         return store_##file_name(policy->governor_data, buf, count);    \
 992 }
 993
 994 #define show_store_gov_pol_sys(file_name)                               \
 995 show_gov_pol_sys(file_name);                                            \
 996 store_gov_pol_sys(file_name)
 997
 998 show_store_gov_pol_sys(target_loads);
 999 show_store_gov_pol_sys(above_hispeed_delay);
1000 show_store_gov_pol_sys(hispeed_freq);
1001 show_store_gov_pol_sys(go_hispeed_load);
1002 show_store_gov_pol_sys(min_sample_time);
1003 show_store_gov_pol_sys(timer_rate);
1004 show_store_gov_pol_sys(timer_slack);
1005 show_store_gov_pol_sys(boost);
1006 store_gov_pol_sys(boostpulse);
1007 show_store_gov_pol_sys(boostpulse_duration);
1008 show_store_gov_pol_sys(io_is_busy);
1009
1010 #define gov_sys_attr_rw(_name)                                          \
1011 static struct global_attr _name##_gov_sys =                             \
1012 __ATTR(_name, 0644, show_##_name##_gov_sys, store_##_name##_gov_sys)
1013
1014 #define gov_pol_attr_rw(_name)                                          \
1015 static struct freq_attr _name##_gov_pol =                               \
1016 __ATTR(_name, 0644, show_##_name##_gov_pol, store_##_name##_gov_pol)
1017
1018 #define gov_sys_pol_attr_rw(_name)                                      \
1019         gov_sys_attr_rw(_name);                                         \
1020         gov_pol_attr_rw(_name)
1021
1022 gov_sys_pol_attr_rw(target_loads);
1023 gov_sys_pol_attr_rw(above_hispeed_delay);
1024 gov_sys_pol_attr_rw(hispeed_freq);
1025 gov_sys_pol_attr_rw(go_hispeed_load);
1026 gov_sys_pol_attr_rw(min_sample_time);
1027 gov_sys_pol_attr_rw(timer_rate);
1028 gov_sys_pol_attr_rw(timer_slack);
1029 gov_sys_pol_attr_rw(boost);
1030 gov_sys_pol_attr_rw(boostpulse_duration);
1031 gov_sys_pol_attr_rw(io_is_busy);
1032
1033 static struct global_attr boostpulse_gov_sys =
1034         __ATTR(boostpulse, 0200, NULL, store_boostpulse_gov_sys);
1035
1036 static struct freq_attr boostpulse_gov_pol =
1037         __ATTR(boostpulse, 0200, NULL, store_boostpulse_gov_pol);
1038
1039 /* One Governor instance for entire system */
1040 static struct attribute *interactive_attributes_gov_sys[] = {
1041         &target_loads_gov_sys.attr,
1042         &above_hispeed_delay_gov_sys.attr,
1043         &hispeed_freq_gov_sys.attr,
1044         &go_hispeed_load_gov_sys.attr,
1045         &min_sample_time_gov_sys.attr,
1046         &timer_rate_gov_sys.attr,
1047         &timer_slack_gov_sys.attr,
1048         &boost_gov_sys.attr,
1049         &boostpulse_gov_sys.attr,
1050         &boostpulse_duration_gov_sys.attr,
1051         &io_is_busy_gov_sys.attr,
1052         NULL,
1053 };
1054
1055 static struct attribute_group interactive_attr_group_gov_sys = {
1056         .attrs = interactive_attributes_gov_sys,
1057         .name = "interactive",
1058 };
1059
1060 /* Per policy governor instance */
1061 static struct attribute *interactive_attributes_gov_pol[] = {
1062         &target_loads_gov_pol.attr,
1063         &above_hispeed_delay_gov_pol.attr,
1064         &hispeed_freq_gov_pol.attr,
1065         &go_hispeed_load_gov_pol.attr,
1066         &min_sample_time_gov_pol.attr,
1067         &timer_rate_gov_pol.attr,
1068         &timer_slack_gov_pol.attr,
1069         &boost_gov_pol.attr,
1070         &boostpulse_gov_pol.attr,
1071         &boostpulse_duration_gov_pol.attr,
1072         &io_is_busy_gov_pol.attr,
1073         NULL,
1074 };
1075
1076 static struct attribute_group interactive_attr_group_gov_pol = {
1077         .attrs = interactive_attributes_gov_pol,
1078         .name = "interactive",
1079 };
1080
1081 static struct attribute_group *get_sysfs_attr(void)
1082 {
1083         if (have_governor_per_policy())
1084                 return &interactive_attr_group_gov_pol;
1085         else
1086                 return &interactive_attr_group_gov_sys;
1087 }
1088
1089 static int cpufreq_interactive_idle_notifier(struct notifier_block *nb,
1090                                              unsigned long val,
1091                                              void *data)
1092 {
1093         switch (val) {
1094         case IDLE_START:
1095                 cpufreq_interactive_idle_start();
1096                 break;
1097         case IDLE_END:
1098                 cpufreq_interactive_idle_end();
1099                 break;
1100         }
1101
1102         return 0;
1103 }
1104
1105 static struct notifier_block cpufreq_interactive_idle_nb = {
1106         .notifier_call = cpufreq_interactive_idle_notifier,
1107 };
1108
1109 static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
1110                 unsigned int event)
1111 {
1112         int rc;
1113         unsigned int j;
1114         struct cpufreq_interactive_cpuinfo *pcpu;
1115         struct cpufreq_frequency_table *freq_table;
1116         struct cpufreq_interactive_tunables *tunables;
1117
1118         if (have_governor_per_policy())
1119                 tunables = policy->governor_data;
1120         else
1121                 tunables = common_tunables;
1122
1123         WARN_ON(!tunables && (event != CPUFREQ_GOV_POLICY_INIT));
1124
1125         switch (event) {
1126         case CPUFREQ_GOV_POLICY_INIT:
1127                 if (have_governor_per_policy()) {
1128                         WARN_ON(tunables);
1129                 } else if (tunables) {
1130                         tunables->usage_count++;
1131                         policy->governor_data = tunables;
1132                         return 0;
1133                 }
1134
1135                 tunables = kzalloc(sizeof(*tunables), GFP_KERNEL);
1136                 if (!tunables) {
1137                         pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__);
1138                         return -ENOMEM;
1139                 }
1140
1141                 tunables->usage_count = 1;
1142                 tunables->above_hispeed_delay = default_above_hispeed_delay;
1143                 tunables->nabove_hispeed_delay =
1144                         ARRAY_SIZE(default_above_hispeed_delay);
1145                 tunables->go_hispeed_load = DEFAULT_GO_HISPEED_LOAD;
1146                 tunables->target_loads = default_target_loads;
1147                 tunables->ntarget_loads = ARRAY_SIZE(default_target_loads);
1148                 tunables->min_sample_time = DEFAULT_MIN_SAMPLE_TIME;
1149                 tunables->timer_rate = DEFAULT_TIMER_RATE;
1150                 tunables->boostpulse_duration_val = DEFAULT_MIN_SAMPLE_TIME;
1151                 tunables->timer_slack_val = DEFAULT_TIMER_SLACK;
1152
1153                 spin_lock_init(&tunables->target_loads_lock);
1154                 spin_lock_init(&tunables->above_hispeed_delay_lock);
1155
1156                 policy->governor_data = tunables;
1157                 if (!have_governor_per_policy()) {
1158                         common_tunables = tunables;
1159                         WARN_ON(cpufreq_get_global_kobject());
1160                 }
1161
1162                 rc = sysfs_create_group(get_governor_parent_kobj(policy),
1163                                 get_sysfs_attr());
1164                 if (rc) {
1165                         kfree(tunables);
1166                         policy->governor_data = NULL;
1167                         if (!have_governor_per_policy())
1168                                 common_tunables = NULL;
1169                         return rc;
1170                 }
1171
1172                 if (!policy->governor->initialized) {
1173                         idle_notifier_register(&cpufreq_interactive_idle_nb);
1174                         cpufreq_register_notifier(&cpufreq_notifier_block,
1175                                         CPUFREQ_TRANSITION_NOTIFIER);
1176                 }
1177
1178                 break;
1179
1180         case CPUFREQ_GOV_POLICY_EXIT:
1181                 if (!--tunables->usage_count) {
1182                         if (policy->governor->initialized == 1) {
1183                                 cpufreq_unregister_notifier(&cpufreq_notifier_block,
1184                                                 CPUFREQ_TRANSITION_NOTIFIER);
1185                                 idle_notifier_unregister(&cpufreq_interactive_idle_nb);
1186                         }
1187
1188                         sysfs_remove_group(get_governor_parent_kobj(policy),
1189                                         get_sysfs_attr());
1190
1191                         if (!have_governor_per_policy())
1192                                 cpufreq_put_global_kobject();
1193
1194                         kfree(tunables);
1195                         common_tunables = NULL;
1196                 }
1197
1198                 policy->governor_data = NULL;
1199                 break;
1200
1201         case CPUFREQ_GOV_START:
1202                 mutex_lock(&gov_lock);
1203
1204                 freq_table = cpufreq_frequency_get_table(policy->cpu);
1205                 if (!tunables->hispeed_freq)
1206                         tunables->hispeed_freq = policy->max;
1207
1208                 for_each_cpu(j, policy->cpus) {
1209                         pcpu = &per_cpu(cpuinfo, j);
1210                         pcpu->policy = policy;
1211                         pcpu->target_freq = policy->cur;
1212                         pcpu->freq_table = freq_table;
1213                         pcpu->floor_freq = pcpu->target_freq;
1214                         pcpu->floor_validate_time =
1215                                 ktime_to_us(ktime_get());
1216                         pcpu->hispeed_validate_time =
1217                                 pcpu->floor_validate_time;
1218                         down_write(&pcpu->enable_sem);
1219                         del_timer_sync(&pcpu->cpu_timer);
1220                         del_timer_sync(&pcpu->cpu_slack_timer);
1221                         cpufreq_interactive_timer_start(tunables, j);
1222                         pcpu->governor_enabled = 1;
1223                         up_write(&pcpu->enable_sem);
1224                 }
1225
1226                 mutex_unlock(&gov_lock);
1227                 break;
1228
1229         case CPUFREQ_GOV_STOP:
1230                 mutex_lock(&gov_lock);
1231                 for_each_cpu(j, policy->cpus) {
1232                         pcpu = &per_cpu(cpuinfo, j);
1233                         down_write(&pcpu->enable_sem);
1234                         pcpu->governor_enabled = 0;
1235                         del_timer_sync(&pcpu->cpu_timer);
1236                         del_timer_sync(&pcpu->cpu_slack_timer);
1237                         up_write(&pcpu->enable_sem);
1238                 }
1239
1240                 mutex_unlock(&gov_lock);
1241                 break;
1242
1243         case CPUFREQ_GOV_LIMITS:
1244                 if (policy->max < policy->cur)
1245                         __cpufreq_driver_target(policy,
1246                                         policy->max, CPUFREQ_RELATION_H);
1247                 else if (policy->min > policy->cur)
1248                         __cpufreq_driver_target(policy,
1249                                         policy->min, CPUFREQ_RELATION_L);
1250                 for_each_cpu(j, policy->cpus) {
1251                         pcpu = &per_cpu(cpuinfo, j);
1252
1253                         /* hold write semaphore to avoid race */
1254                         down_write(&pcpu->enable_sem);
1255                         if (pcpu->governor_enabled == 0) {
1256                                 up_write(&pcpu->enable_sem);
1257                                 continue;
1258                         }
1259
1260                         /* update target_freq firstly */
1261                         if (policy->max < pcpu->target_freq)
1262                                 pcpu->target_freq = policy->max;
1263                         else if (policy->min > pcpu->target_freq)
1264                                 pcpu->target_freq = policy->min;
1265
1266                         /* Reschedule timer.
1267                          * Delete the timers, else the timer callback may
1268                          * return without re-arm the timer when failed
1269                          * acquire the semaphore. This race may cause timer
1270                          * stopped unexpectedly.
1271                          */
1272                         del_timer_sync(&pcpu->cpu_timer);
1273                         del_timer_sync(&pcpu->cpu_slack_timer);
1274                         cpufreq_interactive_timer_start(tunables, j);
1275                         up_write(&pcpu->enable_sem);
1276                 }
1277                 break;
1278         }
1279         return 0;
1280 }
1281
1282 #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE
1283 static
1284 #endif
1285 struct cpufreq_governor cpufreq_gov_interactive = {
1286         .name = "interactive",
1287         .governor = cpufreq_governor_interactive,
1288         .max_transition_latency = 10000000,
1289         .owner = THIS_MODULE,
1290 };
1291
1292 static void cpufreq_interactive_nop_timer(unsigned long data)
1293 {
1294 }
1295
1296 static int __init cpufreq_interactive_init(void)
1297 {
1298         unsigned int i;
1299         struct cpufreq_interactive_cpuinfo *pcpu;
1300         struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
1301
1302         /* Initalize per-cpu timers */
1303         for_each_possible_cpu(i) {
1304                 pcpu = &per_cpu(cpuinfo, i);
1305                 init_timer_deferrable(&pcpu->cpu_timer);
1306                 pcpu->cpu_timer.function = cpufreq_interactive_timer;
1307                 pcpu->cpu_timer.data = i;
1308                 init_timer(&pcpu->cpu_slack_timer);
1309                 pcpu->cpu_slack_timer.function = cpufreq_interactive_nop_timer;
1310                 spin_lock_init(&pcpu->load_lock);
1311                 init_rwsem(&pcpu->enable_sem);
1312         }
1313
1314         spin_lock_init(&speedchange_cpumask_lock);
1315         mutex_init(&gov_lock);
1316         speedchange_task =
1317                 kthread_create(cpufreq_interactive_speedchange_task, NULL,
1318                                "cfinteractive");
1319         if (IS_ERR(speedchange_task))
1320                 return PTR_ERR(speedchange_task);
1321
1322         sched_setscheduler_nocheck(speedchange_task, SCHED_FIFO, &param);
1323         get_task_struct(speedchange_task);
1324
1325         /* NB: wake up so the thread does not look hung to the freezer */
1326         wake_up_process(speedchange_task);
1327
1328         return cpufreq_register_governor(&cpufreq_gov_interactive);
1329 }
1330
1331 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE
1332 fs_initcall(cpufreq_interactive_init);
1333 #else
1334 module_init(cpufreq_interactive_init);
1335 #endif
1336
1337 static void __exit cpufreq_interactive_exit(void)
1338 {
1339         cpufreq_unregister_governor(&cpufreq_gov_interactive);
1340         kthread_stop(speedchange_task);
1341         put_task_struct(speedchange_task);
1342 }
1343
1344 module_exit(cpufreq_interactive_exit);
1345
1346 MODULE_AUTHOR("Mike Chan <mike@android.com>");
1347 MODULE_DESCRIPTION("'cpufreq_interactive' - A cpufreq governor for "
1348         "Latency sensitive workloads");
1349 MODULE_LICENSE("GPL");