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 #include <linux/reboot.h>
  35
  36 #define CREATE_TRACE_POINTS
  37 #include <trace/events/cpufreq_interactive.h>
  38
  39 struct cpufreq_interactive_cpuinfo {
  40         struct timer_list cpu_timer;
  41         struct timer_list cpu_slack_timer;
  42         spinlock_t load_lock; /* protects the next 4 fields */
  43         u64 time_in_idle;
  44         u64 time_in_idle_timestamp;
  45         u64 cputime_speedadj;
  46         u64 cputime_speedadj_timestamp;
  47         struct cpufreq_policy *policy;
  48         struct cpufreq_frequency_table *freq_table;
  49         spinlock_t target_freq_lock; /*protects target freq */
  50         unsigned int target_freq;
  51         unsigned int floor_freq;
  52         unsigned int max_freq;
  53         u64 floor_validate_time;
  54         u64 hispeed_validate_time;
  55         struct rw_semaphore enable_sem;
  56         int governor_enabled;
  57 };
  58
  59 static DEFINE_PER_CPU(struct cpufreq_interactive_cpuinfo, cpuinfo);
  60
  61 /* realtime thread handles frequency scaling */
  62 static struct task_struct *speedchange_task;
  63 static cpumask_t speedchange_cpumask;
  64 static spinlock_t speedchange_cpumask_lock;
  65 static struct mutex gov_lock;
  66
  67 /* Target load.  Lower values result in higher CPU speeds. */
  68 #define DEFAULT_TARGET_LOAD 90
  69 static unsigned int default_target_loads[] = {DEFAULT_TARGET_LOAD};
  70
  71 #define DEFAULT_TIMER_RATE (20 * USEC_PER_MSEC)
  72 #define DEFAULT_ABOVE_HISPEED_DELAY DEFAULT_TIMER_RATE
  73 static unsigned int default_above_hispeed_delay[] = {
  74         DEFAULT_ABOVE_HISPEED_DELAY };
  75
  76 struct cpufreq_interactive_tunables {
  77         int usage_count;
  78         /* Hi speed to bump to from lo speed when load burst (default max) */
  79         unsigned int hispeed_freq;
  80         /* Go to hi speed when CPU load at or above this value. */
  81 #define DEFAULT_GO_HISPEED_LOAD 99
  82         unsigned long go_hispeed_load;
  83         /* Target load. Lower values result in higher CPU speeds. */
  84         spinlock_t target_loads_lock;
  85         unsigned int *target_loads;
  86         int ntarget_loads;
  87         /*
  88          * The minimum amount of time to spend at a frequency before we can ramp
  89          * down.
  90          */
  91 #define DEFAULT_MIN_SAMPLE_TIME (80 * USEC_PER_MSEC)
  92         unsigned long min_sample_time;
  93         /*
  94          * The sample rate of the timer used to increase frequency
  95          */
  96         unsigned long timer_rate;
  97         /*
  98          * Wait this long before raising speed above hispeed, by default a
  99          * single timer interval.
 100          */
 101         spinlock_t above_hispeed_delay_lock;
 102         unsigned int *above_hispeed_delay;
 103         int nabove_hispeed_delay;
 104         /* Non-zero means indefinite speed boost active */
 105         int boost_val;
 106         /* Duration of a boot pulse in usecs */
 107         int boostpulse_duration_val;
 108         /* End time of boost pulse in ktime converted to usecs */
 109         u64 boostpulse_endtime;
 110         bool boosted;
 111         /*
 112          * Max additional time to wait in idle, beyond timer_rate, at speeds
 113          * above minimum before wakeup to reduce speed, or -1 if unnecessary.
 114          */
 115 #define DEFAULT_TIMER_SLACK (4 * DEFAULT_TIMER_RATE)
 116         int timer_slack_val;
 117         bool io_is_busy;
 118 };
 119
 120 /* For cases where we have single governor instance for system */
 121 static struct cpufreq_interactive_tunables *common_tunables;
 122 #define GOVERNOR_BOOT_TIME      (50*HZ)
 123 static unsigned long boot_done;
 124
 125 static struct attribute_group *get_sysfs_attr(void);
 126
 127 static void cpufreq_interactive_timer_resched(
 128         struct cpufreq_interactive_cpuinfo *pcpu)
 129 {
 130         struct cpufreq_interactive_tunables *tunables =
 131                 pcpu->policy->governor_data;
 132         unsigned long expires;
 133         unsigned long flags;
 134
 135         spin_lock_irqsave(&pcpu->load_lock, flags);
 136         pcpu->time_in_idle =
 137                 get_cpu_idle_time(smp_processor_id(),
 138                                   &pcpu->time_in_idle_timestamp,
 139                                   tunables->io_is_busy);
 140         pcpu->cputime_speedadj = 0;
 141         pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp;
 142         expires = jiffies + usecs_to_jiffies(tunables->timer_rate);
 143         mod_timer_pinned(&pcpu->cpu_timer, expires);
 144
 145         if (tunables->timer_slack_val >= 0 &&
 146             pcpu->target_freq > pcpu->policy->min) {
 147                 expires += usecs_to_jiffies(tunables->timer_slack_val);
 148                 mod_timer_pinned(&pcpu->cpu_slack_timer, expires);
 149         }
 150
 151         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 152 }
 153
 154 /* The caller shall take enable_sem write semaphore to avoid any timer race.
 155  * The cpu_timer and cpu_slack_timer must be deactivated when calling this
 156  * function.
 157  */
 158 static void cpufreq_interactive_timer_start(
 159         struct cpufreq_interactive_tunables *tunables, int cpu)
 160 {
 161         struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
 162         unsigned long expires = jiffies +
 163                 usecs_to_jiffies(tunables->timer_rate);
 164         unsigned long flags;
 165
 166         pcpu->cpu_timer.expires = expires;
 167         add_timer_on(&pcpu->cpu_timer, cpu);
 168         if (tunables->timer_slack_val >= 0 &&
 169             pcpu->target_freq > pcpu->policy->min) {
 170                 expires += usecs_to_jiffies(tunables->timer_slack_val);
 171                 pcpu->cpu_slack_timer.expires = expires;
 172                 add_timer_on(&pcpu->cpu_slack_timer, cpu);
 173         }
 174
 175         spin_lock_irqsave(&pcpu->load_lock, flags);
 176         pcpu->time_in_idle =
 177                 get_cpu_idle_time(cpu, &pcpu->time_in_idle_timestamp,
 178                                   tunables->io_is_busy);
 179         pcpu->cputime_speedadj = 0;
 180         pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp;
 181         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 182 }
 183
 184 static unsigned int freq_to_above_hispeed_delay(
 185         struct cpufreq_interactive_tunables *tunables,
 186         unsigned int freq)
 187 {
 188         int i;
 189         unsigned int ret;
 190         unsigned long flags;
 191
 192         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 193
 194         for (i = 0; i < tunables->nabove_hispeed_delay - 1 &&
 195                         freq >= tunables->above_hispeed_delay[i+1]; i += 2)
 196                 ;
 197
 198         ret = tunables->above_hispeed_delay[i];
 199         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 200         return ret;
 201 }
 202
 203 static unsigned int freq_to_targetload(
 204         struct cpufreq_interactive_tunables *tunables, unsigned int freq)
 205 {
 206         int i;
 207         unsigned int ret;
 208         unsigned long flags;
 209
 210         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 211
 212         for (i = 0; i < tunables->ntarget_loads - 1 &&
 213                     freq >= tunables->target_loads[i+1]; i += 2)
 214                 ;
 215
 216         ret = tunables->target_loads[i];
 217         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 218         return ret;
 219 }
 220
 221 /*
 222  * If increasing frequencies never map to a lower target load then
 223  * choose_freq() will find the minimum frequency that does not exceed its
 224  * target load given the current load.
 225  */
 226 static unsigned int choose_freq(struct cpufreq_interactive_cpuinfo *pcpu,
 227                 unsigned int loadadjfreq)
 228 {
 229         unsigned int freq = pcpu->policy->cur;
 230         unsigned int prevfreq, freqmin, freqmax;
 231         unsigned int tl;
 232         int index;
 233
 234         freqmin = 0;
 235         freqmax = UINT_MAX;
 236
 237         do {
 238                 prevfreq = freq;
 239                 tl = freq_to_targetload(pcpu->policy->governor_data, freq);
 240
 241                 /*
 242                  * Find the lowest frequency where the computed load is less
 243                  * than or equal to the target load.
 244                  */
 245
 246                 if (cpufreq_frequency_table_target(
 247                             pcpu->policy, pcpu->freq_table, loadadjfreq / tl,
 248                             CPUFREQ_RELATION_L, &index))
 249                         break;
 250                 freq = pcpu->freq_table[index].frequency;
 251
 252                 if (freq > prevfreq) {
 253                         /* The previous frequency is too low. */
 254                         freqmin = prevfreq;
 255
 256                         if (freq >= freqmax) {
 257                                 /*
 258                                  * Find the highest frequency that is less
 259                                  * than freqmax.
 260                                  */
 261                                 if (cpufreq_frequency_table_target(
 262                                             pcpu->policy, pcpu->freq_table,
 263                                             freqmax - 1, CPUFREQ_RELATION_H,
 264                                             &index))
 265                                         break;
 266                                 freq = pcpu->freq_table[index].frequency;
 267
 268                                 if (freq == freqmin) {
 269                                         /*
 270                                          * The first frequency below freqmax
 271                                          * has already been found to be too
 272                                          * low.  freqmax is the lowest speed
 273                                          * we found that is fast enough.
 274                                          */
 275                                         freq = freqmax;
 276                                         break;
 277                                 }
 278                         }
 279                 } else if (freq < prevfreq) {
 280                         /* The previous frequency is high enough. */
 281                         freqmax = prevfreq;
 282
 283                         if (freq <= freqmin) {
 284                                 /*
 285                                  * Find the lowest frequency that is higher
 286                                  * than freqmin.
 287                                  */
 288                                 if (cpufreq_frequency_table_target(
 289                                             pcpu->policy, pcpu->freq_table,
 290                                             freqmin + 1, CPUFREQ_RELATION_L,
 291                                             &index))
 292                                         break;
 293                                 freq = pcpu->freq_table[index].frequency;
 294
 295                                 /*
 296                                  * If freqmax is the first frequency above
 297                                  * freqmin then we have already found that
 298                                  * this speed is fast enough.
 299                                  */
 300                                 if (freq == freqmax)
 301                                         break;
 302                         }
 303                 }
 304
 305                 /* If same frequency chosen as previous then done. */
 306         } while (freq != prevfreq);
 307
 308         return freq;
 309 }
 310
 311 static u64 update_load(int cpu)
 312 {
 313         struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
 314         struct cpufreq_interactive_tunables *tunables =
 315                 pcpu->policy->governor_data;
 316         u64 now;
 317         u64 now_idle;
 318         u64 delta_idle;
 319         u64 delta_time;
 320         u64 active_time;
 321
 322         now_idle = get_cpu_idle_time(cpu, &now, tunables->io_is_busy);
 323         delta_idle = (now_idle - pcpu->time_in_idle);
 324         delta_time = (now - pcpu->time_in_idle_timestamp);
 325
 326         if (delta_time <= delta_idle)
 327                 active_time = 0;
 328         else
 329                 active_time = delta_time - delta_idle;
 330
 331         pcpu->cputime_speedadj += active_time * pcpu->policy->cur;
 332
 333         pcpu->time_in_idle = now_idle;
 334         pcpu->time_in_idle_timestamp = now;
 335         return now;
 336 }
 337
 338 static void cpufreq_interactive_timer(unsigned long data)
 339 {
 340         u64 now;
 341         unsigned int delta_time;
 342         u64 cputime_speedadj;
 343         int cpu_load;
 344         struct cpufreq_interactive_cpuinfo *pcpu =
 345                 &per_cpu(cpuinfo, data);
 346         struct cpufreq_interactive_tunables *tunables =
 347                 pcpu->policy->governor_data;
 348         unsigned int new_freq;
 349         unsigned int loadadjfreq;
 350         unsigned int index;
 351         unsigned long flags;
 352
 353         if (!down_read_trylock(&pcpu->enable_sem))
 354                 return;
 355         if (!pcpu->governor_enabled)
 356                 goto exit;
 357
 358         spin_lock_irqsave(&pcpu->load_lock, flags);
 359         now = update_load(data);
 360         delta_time = (unsigned int)(now - pcpu->cputime_speedadj_timestamp);
 361         cputime_speedadj = pcpu->cputime_speedadj;
 362         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 363
 364         if (WARN_ON_ONCE(!delta_time))
 365                 goto rearm;
 366
 367         spin_lock_irqsave(&pcpu->target_freq_lock, flags);
 368         do_div(cputime_speedadj, delta_time);
 369         loadadjfreq = (unsigned int)cputime_speedadj * 100;
 370         cpu_load = loadadjfreq / pcpu->target_freq;
 371         tunables->boosted = tunables->boost_val || now < tunables->boostpulse_endtime;
 372
 373         if (cpu_load >= tunables->go_hispeed_load || tunables->boosted) {
 374                 if (pcpu->target_freq < tunables->hispeed_freq) {
 375                         new_freq = tunables->hispeed_freq;
 376                 } else {
 377                         new_freq = choose_freq(pcpu, loadadjfreq);
 378
 379                         if (new_freq < tunables->hispeed_freq)
 380                                 new_freq = tunables->hispeed_freq;
 381                 }
 382         } else {
 383                 new_freq = choose_freq(pcpu, loadadjfreq);
 384                 if (new_freq > tunables->hispeed_freq &&
 385                                 pcpu->target_freq < tunables->hispeed_freq)
 386                         new_freq = tunables->hispeed_freq;
 387         }
 388
 389         if (pcpu->target_freq >= tunables->hispeed_freq &&
 390             new_freq > pcpu->target_freq &&
 391             now - pcpu->hispeed_validate_time <
 392             freq_to_above_hispeed_delay(tunables, pcpu->target_freq)) {
 393                 trace_cpufreq_interactive_notyet(
 394                         data, cpu_load, pcpu->target_freq,
 395                         pcpu->policy->cur, new_freq);
 396                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 397                 goto rearm;
 398         }
 399
 400         pcpu->hispeed_validate_time = now;
 401
 402         if (cpufreq_frequency_table_target(pcpu->policy, pcpu->freq_table,
 403                                            new_freq, CPUFREQ_RELATION_L,
 404                                            &index)) {
 405                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 406                 goto rearm;
 407         }
 408
 409         new_freq = pcpu->freq_table[index].frequency;
 410
 411         /*
 412          * Do not scale below floor_freq unless we have been at or above the
 413          * floor frequency for the minimum sample time since last validated.
 414          */
 415         if (new_freq < pcpu->floor_freq) {
 416                 if (now - pcpu->floor_validate_time <
 417                                 tunables->min_sample_time) {
 418                         trace_cpufreq_interactive_notyet(
 419                                 data, cpu_load, pcpu->target_freq,
 420                                 pcpu->policy->cur, new_freq);
 421                         spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 422                         goto rearm;
 423                 }
 424         }
 425
 426         /*
 427          * Update the timestamp for checking whether speed has been held at
 428          * or above the selected frequency for a minimum of min_sample_time,
 429          * if not boosted to hispeed_freq.  If boosted to hispeed_freq then we
 430          * allow the speed to drop as soon as the boostpulse duration expires
 431          * (or the indefinite boost is turned off).
 432          */
 433
 434         if (!tunables->boosted || new_freq > tunables->hispeed_freq) {
 435                 pcpu->floor_freq = new_freq;
 436                 pcpu->floor_validate_time = now;
 437         }
 438
 439         if (pcpu->target_freq == new_freq &&
 440                         pcpu->target_freq <= pcpu->policy->cur) {
 441                 trace_cpufreq_interactive_already(
 442                         data, cpu_load, pcpu->target_freq,
 443                         pcpu->policy->cur, new_freq);
 444                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 445                 goto rearm_if_notmax;
 446         }
 447
 448         trace_cpufreq_interactive_target(data, cpu_load, pcpu->target_freq,
 449                                          pcpu->policy->cur, new_freq);
 450
 451         pcpu->target_freq = new_freq;
 452         spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 453         spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 454         cpumask_set_cpu(data, &speedchange_cpumask);
 455         spin_unlock_irqrestore(&speedchange_cpumask_lock, flags);
 456         wake_up_process(speedchange_task);
 457
 458 rearm_if_notmax:
 459         /*
 460          * Already set max speed and don't see a need to change that,
 461          * wait until next idle to re-evaluate, don't need timer.
 462          */
 463         if (pcpu->target_freq == pcpu->policy->max)
 464                 goto exit;
 465
 466 rearm:
 467         if (!timer_pending(&pcpu->cpu_timer))
 468                 cpufreq_interactive_timer_resched(pcpu);
 469
 470 exit:
 471         up_read(&pcpu->enable_sem);
 472         return;
 473 }
 474
 475 static void cpufreq_interactive_idle_start(void)
 476 {
 477         struct cpufreq_interactive_cpuinfo *pcpu =
 478                 &per_cpu(cpuinfo, smp_processor_id());
 479         int pending;
 480
 481         if (!down_read_trylock(&pcpu->enable_sem))
 482                 return;
 483         if (!pcpu->governor_enabled) {
 484                 up_read(&pcpu->enable_sem);
 485                 return;
 486         }
 487
 488         pending = timer_pending(&pcpu->cpu_timer);
 489
 490         if (pcpu->target_freq != pcpu->policy->min) {
 491                 /*
 492                  * Entering idle while not at lowest speed.  On some
 493                  * platforms this can hold the other CPU(s) at that speed
 494                  * even though the CPU is idle. Set a timer to re-evaluate
 495                  * speed so this idle CPU doesn't hold the other CPUs above
 496                  * min indefinitely.  This should probably be a quirk of
 497                  * the CPUFreq driver.
 498                  */
 499                 if (!pending)
 500                         cpufreq_interactive_timer_resched(pcpu);
 501         }
 502
 503         up_read(&pcpu->enable_sem);
 504 }
 505
 506 static void cpufreq_interactive_idle_end(void)
 507 {
 508         struct cpufreq_interactive_cpuinfo *pcpu =
 509                 &per_cpu(cpuinfo, smp_processor_id());
 510
 511         if (!down_read_trylock(&pcpu->enable_sem))
 512                 return;
 513         if (!pcpu->governor_enabled) {
 514                 up_read(&pcpu->enable_sem);
 515                 return;
 516         }
 517
 518         /* Arm the timer for 1-2 ticks later if not already. */
 519         if (!timer_pending(&pcpu->cpu_timer)) {
 520                 cpufreq_interactive_timer_resched(pcpu);
 521         } else if (time_after_eq(jiffies, pcpu->cpu_timer.expires)) {
 522                 del_timer(&pcpu->cpu_timer);
 523                 del_timer(&pcpu->cpu_slack_timer);
 524                 cpufreq_interactive_timer(smp_processor_id());
 525         }
 526
 527         up_read(&pcpu->enable_sem);
 528 }
 529
 530 static int cpufreq_interactive_speedchange_task(void *data)
 531 {
 532         unsigned int cpu;
 533         cpumask_t tmp_mask;
 534         unsigned long flags;
 535         struct cpufreq_interactive_cpuinfo *pcpu;
 536
 537         while (1) {
 538                 set_current_state(TASK_INTERRUPTIBLE);
 539                 spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 540
 541                 if (cpumask_empty(&speedchange_cpumask)) {
 542                         spin_unlock_irqrestore(&speedchange_cpumask_lock,
 543                                                flags);
 544                         schedule();
 545
 546                         if (kthread_should_stop())
 547                                 break;
 548
 549                         spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 550                 }
 551
 552                 set_current_state(TASK_RUNNING);
 553                 tmp_mask = speedchange_cpumask;
 554                 cpumask_clear(&speedchange_cpumask);
 555                 spin_unlock_irqrestore(&speedchange_cpumask_lock, flags);
 556
 557                 for_each_cpu(cpu, &tmp_mask) {
 558                         unsigned int j;
 559                         unsigned int max_freq = 0;
 560
 561                         pcpu = &per_cpu(cpuinfo, cpu);
 562                         if (!down_read_trylock(&pcpu->enable_sem))
 563                                 continue;
 564                         if (!pcpu->governor_enabled) {
 565                                 up_read(&pcpu->enable_sem);
 566                                 continue;
 567                         }
 568
 569                         for_each_cpu(j, pcpu->policy->cpus) {
 570                                 struct cpufreq_interactive_cpuinfo *pjcpu =
 571                                         &per_cpu(cpuinfo, j);
 572
 573                                 if (pjcpu->target_freq > max_freq)
 574                                         max_freq = pjcpu->target_freq;
 575                         }
 576
 577                         if (max_freq != pcpu->policy->cur)
 578                                 __cpufreq_driver_target(pcpu->policy,
 579                                                         max_freq,
 580                                                         CPUFREQ_RELATION_H);
 581                         trace_cpufreq_interactive_setspeed(cpu,
 582                                                      pcpu->target_freq,
 583                                                      pcpu->policy->cur);
 584
 585                         up_read(&pcpu->enable_sem);
 586                 }
 587         }
 588
 589         return 0;
 590 }
 591
 592 static void cpufreq_interactive_boost(struct cpufreq_interactive_tunables *tunables)
 593 {
 594         int i;
 595         int anyboost = 0;
 596         unsigned long flags[2];
 597         struct cpufreq_interactive_cpuinfo *pcpu;
 598
 599         tunables->boosted = true;
 600
 601         spin_lock_irqsave(&speedchange_cpumask_lock, flags[0]);
 602
 603         for_each_online_cpu(i) {
 604                 pcpu = &per_cpu(cpuinfo, i);
 605                 if (tunables != pcpu->policy->governor_data)
 606                         continue;
 607
 608                 spin_lock_irqsave(&pcpu->target_freq_lock, flags[1]);
 609                 if (pcpu->target_freq < tunables->hispeed_freq) {
 610                         pcpu->target_freq = tunables->hispeed_freq;
 611                         cpumask_set_cpu(i, &speedchange_cpumask);
 612                         pcpu->hispeed_validate_time =
 613                                 ktime_to_us(ktime_get());
 614                         anyboost = 1;
 615                 }
 616
 617                 /*
 618                  * Set floor freq and (re)start timer for when last
 619                  * validated.
 620                  */
 621
 622                 pcpu->floor_freq = tunables->hispeed_freq;
 623                 pcpu->floor_validate_time = ktime_to_us(ktime_get());
 624                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags[1]);
 625         }
 626
 627         spin_unlock_irqrestore(&speedchange_cpumask_lock, flags[0]);
 628
 629         if (anyboost)
 630                 wake_up_process(speedchange_task);
 631 }
 632
 633 static int cpufreq_interactive_notifier(
 634         struct notifier_block *nb, unsigned long val, void *data)
 635 {
 636         struct cpufreq_freqs *freq = data;
 637         struct cpufreq_interactive_cpuinfo *pcpu;
 638         int cpu;
 639         unsigned long flags;
 640
 641         if (val == CPUFREQ_POSTCHANGE) {
 642                 pcpu = &per_cpu(cpuinfo, freq->cpu);
 643                 if (!down_read_trylock(&pcpu->enable_sem))
 644                         return 0;
 645                 if (!pcpu->governor_enabled) {
 646                         up_read(&pcpu->enable_sem);
 647                         return 0;
 648                 }
 649
 650                 for_each_cpu(cpu, pcpu->policy->cpus) {
 651                         struct cpufreq_interactive_cpuinfo *pjcpu =
 652                                 &per_cpu(cpuinfo, cpu);
 653                         if (cpu != freq->cpu) {
 654                                 if (!down_read_trylock(&pjcpu->enable_sem))
 655                                         continue;
 656                                 if (!pjcpu->governor_enabled) {
 657                                         up_read(&pjcpu->enable_sem);
 658                                         continue;
 659                                 }
 660                         }
 661                         spin_lock_irqsave(&pjcpu->load_lock, flags);
 662                         update_load(cpu);
 663                         spin_unlock_irqrestore(&pjcpu->load_lock, flags);
 664                         if (cpu != freq->cpu)
 665                                 up_read(&pjcpu->enable_sem);
 666                 }
 667
 668                 up_read(&pcpu->enable_sem);
 669         }
 670         return 0;
 671 }
 672
 673 static struct notifier_block cpufreq_notifier_block = {
 674         .notifier_call = cpufreq_interactive_notifier,
 675 };
 676
 677 static unsigned int *get_tokenized_data(const char *buf, int *num_tokens)
 678 {
 679         const char *cp;
 680         int i;
 681         int ntokens = 1;
 682         unsigned int *tokenized_data;
 683         int err = -EINVAL;
 684
 685         cp = buf;
 686         while ((cp = strpbrk(cp + 1, " :")))
 687                 ntokens++;
 688
 689         if (!(ntokens & 0x1))
 690                 goto err;
 691
 692         tokenized_data = kmalloc(ntokens * sizeof(unsigned int), GFP_KERNEL);
 693         if (!tokenized_data) {
 694                 err = -ENOMEM;
 695                 goto err;
 696         }
 697
 698         cp = buf;
 699         i = 0;
 700         while (i < ntokens) {
 701                 if (sscanf(cp, "%u", &tokenized_data[i++]) != 1)
 702                         goto err_kfree;
 703
 704                 cp = strpbrk(cp, " :");
 705                 if (!cp)
 706                         break;
 707                 cp++;
 708         }
 709
 710         if (i != ntokens)
 711                 goto err_kfree;
 712
 713         *num_tokens = ntokens;
 714         return tokenized_data;
 715
 716 err_kfree:
 717         kfree(tokenized_data);
 718 err:
 719         return ERR_PTR(err);
 720 }
 721
 722 static ssize_t show_target_loads(
 723         struct cpufreq_interactive_tunables *tunables,
 724         char *buf)
 725 {
 726         int i;
 727         ssize_t ret = 0;
 728         unsigned long flags;
 729
 730         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 731
 732         for (i = 0; i < tunables->ntarget_loads; i++)
 733                 ret += sprintf(buf + ret, "%u%s", tunables->target_loads[i],
 734                                i & 0x1 ? ":" : " ");
 735
 736         sprintf(buf + ret - 1, "\n");
 737         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 738         return ret;
 739 }
 740
 741 static ssize_t store_target_loads(
 742         struct cpufreq_interactive_tunables *tunables,
 743         const char *buf, size_t count)
 744 {
 745         int ntokens;
 746         unsigned int *new_target_loads = NULL;
 747         unsigned long flags;
 748
 749         new_target_loads = get_tokenized_data(buf, &ntokens);
 750         if (IS_ERR(new_target_loads))
 751                 return PTR_RET(new_target_loads);
 752
 753         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 754         if (tunables->target_loads != default_target_loads)
 755                 kfree(tunables->target_loads);
 756         tunables->target_loads = new_target_loads;
 757         tunables->ntarget_loads = ntokens;
 758         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 759         return count;
 760 }
 761
 762 static ssize_t show_above_hispeed_delay(
 763         struct cpufreq_interactive_tunables *tunables, char *buf)
 764 {
 765         int i;
 766         ssize_t ret = 0;
 767         unsigned long flags;
 768
 769         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 770
 771         for (i = 0; i < tunables->nabove_hispeed_delay; i++)
 772                 ret += sprintf(buf + ret, "%u%s",
 773                                tunables->above_hispeed_delay[i],
 774                                i & 0x1 ? ":" : " ");
 775
 776         sprintf(buf + ret - 1, "\n");
 777         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 778         return ret;
 779 }
 780
 781 static ssize_t store_above_hispeed_delay(
 782         struct cpufreq_interactive_tunables *tunables,
 783         const char *buf, size_t count)
 784 {
 785         int ntokens;
 786         unsigned int *new_above_hispeed_delay = NULL;
 787         unsigned long flags;
 788
 789         new_above_hispeed_delay = get_tokenized_data(buf, &ntokens);
 790         if (IS_ERR(new_above_hispeed_delay))
 791                 return PTR_RET(new_above_hispeed_delay);
 792
 793         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 794         if (tunables->above_hispeed_delay != default_above_hispeed_delay)
 795                 kfree(tunables->above_hispeed_delay);
 796         tunables->above_hispeed_delay = new_above_hispeed_delay;
 797         tunables->nabove_hispeed_delay = ntokens;
 798         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 799         return count;
 800
 801 }
 802
 803 static ssize_t show_hispeed_freq(struct cpufreq_interactive_tunables *tunables,
 804                 char *buf)
 805 {
 806         return sprintf(buf, "%u\n", tunables->hispeed_freq);
 807 }
 808
 809 static ssize_t store_hispeed_freq(struct cpufreq_interactive_tunables *tunables,
 810                 const char *buf, size_t count)
 811 {
 812         int ret;
 813         long unsigned int val;
 814
 815         ret = strict_strtoul(buf, 0, &val);
 816         if (ret < 0)
 817                 return ret;
 818         tunables->hispeed_freq = val;
 819         return count;
 820 }
 821
 822 static ssize_t show_go_hispeed_load(struct cpufreq_interactive_tunables
 823                 *tunables, char *buf)
 824 {
 825         return sprintf(buf, "%lu\n", tunables->go_hispeed_load);
 826 }
 827
 828 static ssize_t store_go_hispeed_load(struct cpufreq_interactive_tunables
 829                 *tunables, const char *buf, size_t count)
 830 {
 831         int ret;
 832         unsigned long val;
 833
 834         ret = strict_strtoul(buf, 0, &val);
 835         if (ret < 0)
 836                 return ret;
 837         tunables->go_hispeed_load = val;
 838         return count;
 839 }
 840
 841 static ssize_t show_min_sample_time(struct cpufreq_interactive_tunables
 842                 *tunables, char *buf)
 843 {
 844         return sprintf(buf, "%lu\n", tunables->min_sample_time);
 845 }
 846
 847 static ssize_t store_min_sample_time(struct cpufreq_interactive_tunables
 848                 *tunables, const char *buf, size_t count)
 849 {
 850         int ret;
 851         unsigned long val;
 852
 853         ret = strict_strtoul(buf, 0, &val);
 854         if (ret < 0)
 855                 return ret;
 856         tunables->min_sample_time = val;
 857         return count;
 858 }
 859
 860 static ssize_t show_timer_rate(struct cpufreq_interactive_tunables *tunables,
 861                 char *buf)
 862 {
 863         return sprintf(buf, "%lu\n", tunables->timer_rate);
 864 }
 865
 866 static ssize_t store_timer_rate(struct cpufreq_interactive_tunables *tunables,
 867                 const char *buf, size_t count)
 868 {
 869         int ret;
 870         unsigned long val;
 871
 872         ret = strict_strtoul(buf, 0, &val);
 873         if (ret < 0)
 874                 return ret;
 875         tunables->timer_rate = val;
 876         return count;
 877 }
 878
 879 static ssize_t show_timer_slack(struct cpufreq_interactive_tunables *tunables,
 880                 char *buf)
 881 {
 882         return sprintf(buf, "%d\n", tunables->timer_slack_val);
 883 }
 884
 885 static ssize_t store_timer_slack(struct cpufreq_interactive_tunables *tunables,
 886                 const char *buf, size_t count)
 887 {
 888         int ret;
 889         unsigned long val;
 890
 891         ret = kstrtol(buf, 10, &val);
 892         if (ret < 0)
 893                 return ret;
 894
 895         tunables->timer_slack_val = val;
 896         return count;
 897 }
 898
 899 static ssize_t show_boost(struct cpufreq_interactive_tunables *tunables,
 900                           char *buf)
 901 {
 902         return sprintf(buf, "%d\n", tunables->boost_val);
 903 }
 904
 905 static ssize_t store_boost(struct cpufreq_interactive_tunables *tunables,
 906                            const char *buf, size_t count)
 907 {
 908         int ret;
 909         unsigned long val;
 910
 911         ret = kstrtoul(buf, 0, &val);
 912         if (ret < 0)
 913                 return ret;
 914
 915         tunables->boost_val = val;
 916
 917         if (tunables->boost_val) {
 918                 trace_cpufreq_interactive_boost("on");
 919                 if (!tunables->boosted)
 920                         cpufreq_interactive_boost(tunables);
 921         } else {
 922                 tunables->boostpulse_endtime = ktime_to_us(ktime_get());
 923                 trace_cpufreq_interactive_unboost("off");
 924         }
 925
 926         return count;
 927 }
 928
 929 static ssize_t store_boostpulse(struct cpufreq_interactive_tunables *tunables,
 930                                 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_endtime = ktime_to_us(ktime_get()) +
 940                 tunables->boostpulse_duration_val;
 941         trace_cpufreq_interactive_boost("pulse");
 942         if (!tunables->boosted)
 943                 cpufreq_interactive_boost(tunables);
 944         return count;
 945 }
 946
 947 static ssize_t show_boostpulse_duration(struct cpufreq_interactive_tunables
 948                 *tunables, char *buf)
 949 {
 950         return sprintf(buf, "%d\n", tunables->boostpulse_duration_val);
 951 }
 952
 953 static ssize_t store_boostpulse_duration(struct cpufreq_interactive_tunables
 954                 *tunables, const char *buf, size_t count)
 955 {
 956         int ret;
 957         unsigned long val;
 958
 959         ret = kstrtoul(buf, 0, &val);
 960         if (ret < 0)
 961                 return ret;
 962
 963         tunables->boostpulse_duration_val = val;
 964         return count;
 965 }
 966
 967 static ssize_t show_io_is_busy(struct cpufreq_interactive_tunables *tunables,
 968                 char *buf)
 969 {
 970         return sprintf(buf, "%u\n", tunables->io_is_busy);
 971 }
 972
 973 static ssize_t store_io_is_busy(struct cpufreq_interactive_tunables *tunables,
 974                 const char *buf, size_t count)
 975 {
 976         int ret;
 977         unsigned long val;
 978
 979         ret = kstrtoul(buf, 0, &val);
 980         if (ret < 0)
 981                 return ret;
 982         tunables->io_is_busy = val;
 983         return count;
 984 }
 985
 986 /*
 987  * Create show/store routines
 988  * - sys: One governor instance for complete SYSTEM
 989  * - pol: One governor instance per struct cpufreq_policy
 990  */
 991 #define show_gov_pol_sys(file_name)                                     \
 992 static ssize_t show_##file_name##_gov_sys                               \
 993 (struct kobject *kobj, struct attribute *attr, char *buf)               \
 994 {                                                                       \
 995         return show_##file_name(common_tunables, buf);                  \
 996 }                                                                       \
 997                                                                         \
 998 static ssize_t show_##file_name##_gov_pol                               \
 999 (struct cpufreq_policy *policy, char *buf)                              \
1000 {                                                                       \
1001         return show_##file_name(policy->governor_data, buf);            \
1002 }
1003
1004 #define store_gov_pol_sys(file_name)                                    \
1005 static ssize_t store_##file_name##_gov_sys                              \
1006 (struct kobject *kobj, struct attribute *attr, const char *buf,         \
1007         size_t count)                                                   \
1008 {                                                                       \
1009         return store_##file_name(common_tunables, buf, count);          \
1010 }                                                                       \
1011                                                                         \
1012 static ssize_t store_##file_name##_gov_pol                              \
1013 (struct cpufreq_policy *policy, const char *buf, size_t count)          \
1014 {                                                                       \
1015         return store_##file_name(policy->governor_data, buf, count);    \
1016 }
1017
1018 #define show_store_gov_pol_sys(file_name)                               \
1019 show_gov_pol_sys(file_name);                                            \
1020 store_gov_pol_sys(file_name)
1021
1022 show_store_gov_pol_sys(target_loads);
1023 show_store_gov_pol_sys(above_hispeed_delay);
1024 show_store_gov_pol_sys(hispeed_freq);
1025 show_store_gov_pol_sys(go_hispeed_load);
1026 show_store_gov_pol_sys(min_sample_time);
1027 show_store_gov_pol_sys(timer_rate);
1028 show_store_gov_pol_sys(timer_slack);
1029 show_store_gov_pol_sys(boost);
1030 store_gov_pol_sys(boostpulse);
1031 show_store_gov_pol_sys(boostpulse_duration);
1032 show_store_gov_pol_sys(io_is_busy);
1033
1034 #define gov_sys_attr_rw(_name)                                          \
1035 static struct global_attr _name##_gov_sys =                             \
1036 __ATTR(_name, 0644, show_##_name##_gov_sys, store_##_name##_gov_sys)
1037
1038 #define gov_pol_attr_rw(_name)                                          \
1039 static struct freq_attr _name##_gov_pol =                               \
1040 __ATTR(_name, 0644, show_##_name##_gov_pol, store_##_name##_gov_pol)
1041
1042 #define gov_sys_pol_attr_rw(_name)                                      \
1043         gov_sys_attr_rw(_name);                                         \
1044         gov_pol_attr_rw(_name)
1045
1046 gov_sys_pol_attr_rw(target_loads);
1047 gov_sys_pol_attr_rw(above_hispeed_delay);
1048 gov_sys_pol_attr_rw(hispeed_freq);
1049 gov_sys_pol_attr_rw(go_hispeed_load);
1050 gov_sys_pol_attr_rw(min_sample_time);
1051 gov_sys_pol_attr_rw(timer_rate);
1052 gov_sys_pol_attr_rw(timer_slack);
1053 gov_sys_pol_attr_rw(boost);
1054 gov_sys_pol_attr_rw(boostpulse_duration);
1055 gov_sys_pol_attr_rw(io_is_busy);
1056
1057 static struct global_attr boostpulse_gov_sys =
1058         __ATTR(boostpulse, 0200, NULL, store_boostpulse_gov_sys);
1059
1060 static struct freq_attr boostpulse_gov_pol =
1061         __ATTR(boostpulse, 0200, NULL, store_boostpulse_gov_pol);
1062
1063 /* One Governor instance for entire system */
1064 static struct attribute *interactive_attributes_gov_sys[] = {
1065         &target_loads_gov_sys.attr,
1066         &above_hispeed_delay_gov_sys.attr,
1067         &hispeed_freq_gov_sys.attr,
1068         &go_hispeed_load_gov_sys.attr,
1069         &min_sample_time_gov_sys.attr,
1070         &timer_rate_gov_sys.attr,
1071         &timer_slack_gov_sys.attr,
1072         &boost_gov_sys.attr,
1073         &boostpulse_gov_sys.attr,
1074         &boostpulse_duration_gov_sys.attr,
1075         &io_is_busy_gov_sys.attr,
1076         NULL,
1077 };
1078
1079 static struct attribute_group interactive_attr_group_gov_sys = {
1080         .attrs = interactive_attributes_gov_sys,
1081         .name = "interactive",
1082 };
1083
1084 /* Per policy governor instance */
1085 static struct attribute *interactive_attributes_gov_pol[] = {
1086         &target_loads_gov_pol.attr,
1087         &above_hispeed_delay_gov_pol.attr,
1088         &hispeed_freq_gov_pol.attr,
1089         &go_hispeed_load_gov_pol.attr,
1090         &min_sample_time_gov_pol.attr,
1091         &timer_rate_gov_pol.attr,
1092         &timer_slack_gov_pol.attr,
1093         &boost_gov_pol.attr,
1094         &boostpulse_gov_pol.attr,
1095         &boostpulse_duration_gov_pol.attr,
1096         &io_is_busy_gov_pol.attr,
1097         NULL,
1098 };
1099
1100 static struct attribute_group interactive_attr_group_gov_pol = {
1101         .attrs = interactive_attributes_gov_pol,
1102         .name = "interactive",
1103 };
1104
1105 static struct attribute_group *get_sysfs_attr(void)
1106 {
1107         if (have_governor_per_policy())
1108                 return &interactive_attr_group_gov_pol;
1109         else
1110                 return &interactive_attr_group_gov_sys;
1111 }
1112
1113 static int cpufreq_interactive_idle_notifier(struct notifier_block *nb,
1114                                              unsigned long val,
1115                                              void *data)
1116 {
1117         if (time_before(jiffies, boot_done))
1118                 return 0;
1119
1120         switch (val) {
1121         case IDLE_START:
1122                 cpufreq_interactive_idle_start();
1123                 break;
1124         case IDLE_END:
1125                 cpufreq_interactive_idle_end();
1126                 break;
1127         }
1128
1129         return 0;
1130 }
1131
1132 static struct notifier_block cpufreq_interactive_idle_nb = {
1133         .notifier_call = cpufreq_interactive_idle_notifier,
1134 };
1135
1136 #if defined CONFIG_ARCH_SCX35LT8
1137
1138 void cpufreq_interactive_reboot_handler(unsigned int cpu)
1139 {
1140         unsigned int j;
1141         struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
1142
1143         if(!pcpu->governor_enabled)
1144                 return;
1145         mutex_lock(&gov_lock);
1146         for_each_cpu(j, pcpu->policy->cpus) {
1147                 pcpu = &per_cpu(cpuinfo, j);
1148                 down_write(&pcpu->enable_sem);
1149                 pcpu->governor_enabled = 0;
1150                 del_timer_sync(&pcpu->cpu_timer);
1151                 del_timer_sync(&pcpu->cpu_slack_timer);
1152                 up_write(&pcpu->enable_sem);
1153                 }
1154         mutex_unlock(&gov_lock);
1155
1156         __cpufreq_driver_target(pcpu->policy,
1157                                                                 pcpu->policy->max,
1158                                                                 CPUFREQ_RELATION_H);
1159 }
1160 static int cpufreq_interactive_reboot_notifier(
1161         struct notifier_block *nb, unsigned long val, void *data)
1162 {
1163         unsigned int i;
1164
1165         if((SYS_RESTART == val)||(SYS_POWER_OFF == val)){
1166                 for_each_possible_cpu(i){
1167                         cpufreq_interactive_reboot_handler(i);
1168                         }
1169                 }
1170         return 0;
1171 }
1172 static struct notifier_block cpufreq_interactive_reboot_nb = {
1173         .notifier_call = cpufreq_interactive_reboot_notifier,
1174 };
1175 #endif
1176
1177 static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
1178                 unsigned int event)
1179 {
1180         int rc;
1181         unsigned int j;
1182         struct cpufreq_interactive_cpuinfo *pcpu;
1183         struct cpufreq_frequency_table *freq_table;
1184         struct cpufreq_interactive_tunables *tunables;
1185         unsigned long flags;
1186
1187         if (have_governor_per_policy())
1188                 tunables = policy->governor_data;
1189         else
1190                 tunables = common_tunables;
1191
1192         WARN_ON(!tunables && (event != CPUFREQ_GOV_POLICY_INIT));
1193
1194         switch (event) {
1195         case CPUFREQ_GOV_POLICY_INIT:
1196                 if (have_governor_per_policy()) {
1197                         WARN_ON(tunables);
1198                 } else if (tunables) {
1199                         tunables->usage_count++;
1200                         policy->governor_data = tunables;
1201                         return 0;
1202                 }
1203
1204                 tunables = kzalloc(sizeof(*tunables), GFP_KERNEL);
1205                 if (!tunables) {
1206                         pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__);
1207                         return -ENOMEM;
1208                 }
1209
1210                 tunables->usage_count = 1;
1211                 tunables->above_hispeed_delay = default_above_hispeed_delay;
1212                 tunables->nabove_hispeed_delay =
1213                         ARRAY_SIZE(default_above_hispeed_delay);
1214                 tunables->go_hispeed_load = DEFAULT_GO_HISPEED_LOAD;
1215                 tunables->target_loads = default_target_loads;
1216                 tunables->ntarget_loads = ARRAY_SIZE(default_target_loads);
1217                 tunables->min_sample_time = DEFAULT_MIN_SAMPLE_TIME;
1218                 tunables->timer_rate = DEFAULT_TIMER_RATE;
1219                 tunables->boostpulse_duration_val = DEFAULT_MIN_SAMPLE_TIME;
1220                 tunables->timer_slack_val = DEFAULT_TIMER_SLACK;
1221
1222                 spin_lock_init(&tunables->target_loads_lock);
1223                 spin_lock_init(&tunables->above_hispeed_delay_lock);
1224
1225                 policy->governor_data = tunables;
1226                 if (!have_governor_per_policy())
1227                         common_tunables = tunables;
1228
1229                 rc = sysfs_create_group(get_governor_parent_kobj(policy),
1230                                 get_sysfs_attr());
1231                 if (rc) {
1232                         kfree(tunables);
1233                         policy->governor_data = NULL;
1234                         if (!have_governor_per_policy())
1235                                 common_tunables = NULL;
1236                         return rc;
1237                 }
1238
1239                 if (!policy->governor->initialized) {
1240                         idle_notifier_register(&cpufreq_interactive_idle_nb);
1241                         cpufreq_register_notifier(&cpufreq_notifier_block,
1242                                         CPUFREQ_TRANSITION_NOTIFIER);
1243 #if defined CONFIG_ARCH_SCX35LT8
1244                         register_reboot_notifier(&cpufreq_interactive_reboot_nb);
1245 #endif
1246                 }
1247
1248                 break;
1249
1250         case CPUFREQ_GOV_POLICY_EXIT:
1251                 if (!--tunables->usage_count) {
1252                         if (policy->governor->initialized == 1) {
1253                                 cpufreq_unregister_notifier(&cpufreq_notifier_block,
1254                                                 CPUFREQ_TRANSITION_NOTIFIER);
1255                                 idle_notifier_unregister(&cpufreq_interactive_idle_nb);
1256 #if defined CONFIG_ARCH_SCX35LT8
1257                                 unregister_reboot_notifier(&cpufreq_interactive_reboot_nb);
1258 #endif
1259                         }
1260
1261                         sysfs_remove_group(get_governor_parent_kobj(policy),
1262                                         get_sysfs_attr());
1263                         kfree(tunables);
1264                         common_tunables = NULL;
1265                 }
1266
1267                 policy->governor_data = NULL;
1268                 break;
1269
1270         case CPUFREQ_GOV_START:
1271                 mutex_lock(&gov_lock);
1272
1273                 freq_table = cpufreq_frequency_get_table(policy->cpu);
1274                 if (!tunables->hispeed_freq)
1275                         tunables->hispeed_freq = policy->max;
1276
1277                 for_each_cpu(j, policy->cpus) {
1278                         pcpu = &per_cpu(cpuinfo, j);
1279                         pcpu->policy = policy;
1280                         pcpu->target_freq = policy->cur;
1281                         pcpu->freq_table = freq_table;
1282                         pcpu->floor_freq = pcpu->target_freq;
1283                         pcpu->floor_validate_time =
1284                                 ktime_to_us(ktime_get());
1285                         pcpu->hispeed_validate_time =
1286                                 pcpu->floor_validate_time;
1287                         pcpu->max_freq = policy->max;
1288                         down_write(&pcpu->enable_sem);
1289                         del_timer_sync(&pcpu->cpu_timer);
1290                         del_timer_sync(&pcpu->cpu_slack_timer);
1291                         cpufreq_interactive_timer_start(tunables, j);
1292                         pcpu->governor_enabled = 1;
1293                         up_write(&pcpu->enable_sem);
1294                 }
1295
1296                 mutex_unlock(&gov_lock);
1297                 break;
1298
1299         case CPUFREQ_GOV_STOP:
1300                 mutex_lock(&gov_lock);
1301                 for_each_cpu(j, policy->cpus) {
1302                         pcpu = &per_cpu(cpuinfo, j);
1303                         down_write(&pcpu->enable_sem);
1304                         pcpu->governor_enabled = 0;
1305                         del_timer_sync(&pcpu->cpu_timer);
1306                         del_timer_sync(&pcpu->cpu_slack_timer);
1307                         up_write(&pcpu->enable_sem);
1308                 }
1309
1310                 mutex_unlock(&gov_lock);
1311                 break;
1312
1313         case CPUFREQ_GOV_LIMITS:
1314                 if (policy->max < policy->cur)
1315                         __cpufreq_driver_target(policy,
1316                                         policy->max, CPUFREQ_RELATION_H);
1317                 else if (policy->min > policy->cur)
1318                         __cpufreq_driver_target(policy,
1319                                         policy->min, CPUFREQ_RELATION_L);
1320                 for_each_cpu(j, policy->cpus) {
1321                         pcpu = &per_cpu(cpuinfo, j);
1322
1323                         down_read(&pcpu->enable_sem);
1324                         if (pcpu->governor_enabled == 0) {
1325                                 up_read(&pcpu->enable_sem);
1326                                 continue;
1327                         }
1328
1329                         spin_lock_irqsave(&pcpu->target_freq_lock, flags);
1330                         if (policy->max < pcpu->target_freq)
1331                                 pcpu->target_freq = policy->max;
1332                         else if (policy->min > pcpu->target_freq)
1333                                 pcpu->target_freq = policy->min;
1334
1335                         spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
1336                         up_read(&pcpu->enable_sem);
1337
1338                         /* Reschedule timer only if policy->max is raised.
1339                          * Delete the timers, else the timer callback may
1340                          * return without re-arm the timer when failed
1341                          * acquire the semaphore. This race may cause timer
1342                          * stopped unexpectedly.
1343                          */
1344
1345                         if (policy->max > pcpu->max_freq) {
1346                                 down_write(&pcpu->enable_sem);
1347                                 del_timer_sync(&pcpu->cpu_timer);
1348                                 del_timer_sync(&pcpu->cpu_slack_timer);
1349                                 cpufreq_interactive_timer_start(tunables, j);
1350                                 up_write(&pcpu->enable_sem);
1351                         }
1352
1353                         pcpu->max_freq = policy->max;
1354                 }
1355                 break;
1356         }
1357         return 0;
1358 }
1359
1360 #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE
1361 static
1362 #endif
1363 struct cpufreq_governor cpufreq_gov_interactive = {
1364         .name = "interactive",
1365         .governor = cpufreq_governor_interactive,
1366         .max_transition_latency = 10000000,
1367         .owner = THIS_MODULE,
1368 };
1369
1370 static void cpufreq_interactive_nop_timer(unsigned long data)
1371 {
1372 }
1373
1374 static int __init cpufreq_interactive_init(void)
1375 {
1376         unsigned int i;
1377         struct cpufreq_interactive_cpuinfo *pcpu;
1378         struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
1379
1380         boot_done = jiffies + GOVERNOR_BOOT_TIME;
1381         /* Initalize per-cpu timers */
1382         for_each_possible_cpu(i) {
1383                 pcpu = &per_cpu(cpuinfo, i);
1384                 init_timer_deferrable(&pcpu->cpu_timer);
1385                 pcpu->cpu_timer.function = cpufreq_interactive_timer;
1386                 pcpu->cpu_timer.data = i;
1387                 init_timer(&pcpu->cpu_slack_timer);
1388                 pcpu->cpu_slack_timer.function = cpufreq_interactive_nop_timer;
1389                 spin_lock_init(&pcpu->load_lock);
1390                 spin_lock_init(&pcpu->target_freq_lock);
1391                 init_rwsem(&pcpu->enable_sem);
1392         }
1393
1394         spin_lock_init(&speedchange_cpumask_lock);
1395         mutex_init(&gov_lock);
1396         speedchange_task =
1397                 kthread_create(cpufreq_interactive_speedchange_task, NULL,
1398                                "cfinteractive");
1399         if (IS_ERR(speedchange_task))
1400                 return PTR_ERR(speedchange_task);
1401
1402         sched_setscheduler_nocheck(speedchange_task, SCHED_FIFO, &param);
1403         get_task_struct(speedchange_task);
1404
1405         /* NB: wake up so the thread does not look hung to the freezer */
1406         wake_up_process(speedchange_task);
1407
1408         return cpufreq_register_governor(&cpufreq_gov_interactive);
1409 }
1410
1411 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE
1412 fs_initcall(cpufreq_interactive_init);
1413 #else
1414 module_init(cpufreq_interactive_init);
1415 #endif
1416
1417 static void __exit cpufreq_interactive_exit(void)
1418 {
1419         cpufreq_unregister_governor(&cpufreq_gov_interactive);
1420         kthread_stop(speedchange_task);
1421         put_task_struct(speedchange_task);
1422 }
1423
1424 module_exit(cpufreq_interactive_exit);
1425
1426 MODULE_AUTHOR("Mike Chan <mike@android.com>");
1427 MODULE_DESCRIPTION("'cpufreq_interactive' - A cpufreq governor for "
1428         "Latency sensitive workloads");
1429 MODULE_LICENSE("GPL");