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