drivers/cpufreq/cpufreq_interactive.c

   1 /*
   2  * drivers/cpufreq/cpufreq_interactive.c
   3  *
   4  * Copyright (C) 2010 Google, Inc.
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * Author: Mike Chan (mike@android.com)
  16  *
  17  */
  18
  19 #include <linux/cpu.h>
  20 #include <linux/cpumask.h>
  21 #include <linux/cpufreq.h>
  22 #include <linux/module.h>
  23 #include <linux/moduleparam.h>
  24 #include <linux/rwsem.h>
  25 #include <linux/sched.h>
  26 #include <linux/sched/rt.h>
  27 #include <linux/tick.h>
  28 #include <linux/time.h>
  29 #include <linux/timer.h>
  30 #include <linux/workqueue.h>
  31 #include <linux/kthread.h>
  32 #include <linux/slab.h>
  33
  34 #define CREATE_TRACE_POINTS
  35 #include <trace/events/cpufreq_interactive.h>
  36
  37 struct cpufreq_interactive_cpuinfo {
  38         struct timer_list cpu_timer;
  39         struct timer_list cpu_slack_timer;
  40         spinlock_t load_lock; /* protects the next 4 fields */
  41         u64 time_in_idle;
  42         u64 time_in_idle_timestamp;
  43         u64 cputime_speedadj;
  44         u64 cputime_speedadj_timestamp;
  45         struct cpufreq_policy *policy;
  46         struct cpufreq_frequency_table *freq_table;
  47         spinlock_t target_freq_lock; /*protects target freq */
  48         unsigned int target_freq;
  49         unsigned int floor_freq;
  50         unsigned int max_freq;
  51         u64 pol_floor_val_time; /* policy floor_validate_time */
  52         u64 loc_floor_val_time; /* per-cpu floor_validate_time */
  53         u64 pol_hispeed_val_time; /* policy hispeed_validate_time */
  54         u64 loc_hispeed_val_time; /* per-cpu 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
 123 static struct attribute_group *get_sysfs_attr(void);
 124
 125 static void cpufreq_interactive_timer_resched(
 126         struct cpufreq_interactive_cpuinfo *pcpu)
 127 {
 128         struct cpufreq_interactive_tunables *tunables =
 129                 pcpu->policy->governor_data;
 130         unsigned long expires;
 131         unsigned long flags;
 132
 133         spin_lock_irqsave(&pcpu->load_lock, flags);
 134         pcpu->time_in_idle =
 135                 get_cpu_idle_time(smp_processor_id(),
 136                                   &pcpu->time_in_idle_timestamp,
 137                                   tunables->io_is_busy);
 138         pcpu->cputime_speedadj = 0;
 139         pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp;
 140         expires = jiffies + usecs_to_jiffies(tunables->timer_rate);
 141         mod_timer_pinned(&pcpu->cpu_timer, expires);
 142
 143         if (tunables->timer_slack_val >= 0 &&
 144             pcpu->target_freq > pcpu->policy->min) {
 145                 expires += usecs_to_jiffies(tunables->timer_slack_val);
 146                 mod_timer_pinned(&pcpu->cpu_slack_timer, expires);
 147         }
 148
 149         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 150 }
 151
 152 /* The caller shall take enable_sem write semaphore to avoid any timer race.
 153  * The cpu_timer and cpu_slack_timer must be deactivated when calling this
 154  * function.
 155  */
 156 static void cpufreq_interactive_timer_start(
 157         struct cpufreq_interactive_tunables *tunables, int cpu)
 158 {
 159         struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
 160         unsigned long expires = jiffies +
 161                 usecs_to_jiffies(tunables->timer_rate);
 162         unsigned long flags;
 163
 164         pcpu->cpu_timer.expires = expires;
 165         add_timer_on(&pcpu->cpu_timer, cpu);
 166         if (tunables->timer_slack_val >= 0 &&
 167             pcpu->target_freq > pcpu->policy->min) {
 168                 expires += usecs_to_jiffies(tunables->timer_slack_val);
 169                 pcpu->cpu_slack_timer.expires = expires;
 170                 add_timer_on(&pcpu->cpu_slack_timer, cpu);
 171         }
 172
 173         spin_lock_irqsave(&pcpu->load_lock, flags);
 174         pcpu->time_in_idle =
 175                 get_cpu_idle_time(cpu, &pcpu->time_in_idle_timestamp,
 176                                   tunables->io_is_busy);
 177         pcpu->cputime_speedadj = 0;
 178         pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp;
 179         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 180 }
 181
 182 static unsigned int freq_to_above_hispeed_delay(
 183         struct cpufreq_interactive_tunables *tunables,
 184         unsigned int freq)
 185 {
 186         int i;
 187         unsigned int ret;
 188         unsigned long flags;
 189
 190         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 191
 192         for (i = 0; i < tunables->nabove_hispeed_delay - 1 &&
 193                         freq >= tunables->above_hispeed_delay[i+1]; i += 2)
 194                 ;
 195
 196         ret = tunables->above_hispeed_delay[i];
 197         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 198         return ret;
 199 }
 200
 201 static unsigned int freq_to_targetload(
 202         struct cpufreq_interactive_tunables *tunables, unsigned int freq)
 203 {
 204         int i;
 205         unsigned int ret;
 206         unsigned long flags;
 207
 208         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 209
 210         for (i = 0; i < tunables->ntarget_loads - 1 &&
 211                     freq >= tunables->target_loads[i+1]; i += 2)
 212                 ;
 213
 214         ret = tunables->target_loads[i];
 215         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 216         return ret;
 217 }
 218
 219 /*
 220  * If increasing frequencies never map to a lower target load then
 221  * choose_freq() will find the minimum frequency that does not exceed its
 222  * target load given the current load.
 223  */
 224 static unsigned int choose_freq(struct cpufreq_interactive_cpuinfo *pcpu,
 225                 unsigned int loadadjfreq)
 226 {
 227         unsigned int freq = pcpu->policy->cur;
 228         unsigned int prevfreq, freqmin, freqmax;
 229         unsigned int tl;
 230         int index;
 231
 232         freqmin = 0;
 233         freqmax = UINT_MAX;
 234
 235         do {
 236                 prevfreq = freq;
 237                 tl = freq_to_targetload(pcpu->policy->governor_data, freq);
 238
 239                 /*
 240                  * Find the lowest frequency where the computed load is less
 241                  * than or equal to the target load.
 242                  */
 243
 244                 if (cpufreq_frequency_table_target(
 245                             pcpu->policy, pcpu->freq_table, loadadjfreq / tl,
 246                             CPUFREQ_RELATION_L, &index))
 247                         break;
 248                 freq = pcpu->freq_table[index].frequency;
 249
 250                 if (freq > prevfreq) {
 251                         /* The previous frequency is too low. */
 252                         freqmin = prevfreq;
 253
 254                         if (freq >= freqmax) {
 255                                 /*
 256                                  * Find the highest frequency that is less
 257                                  * than freqmax.
 258                                  */
 259                                 if (cpufreq_frequency_table_target(
 260                                             pcpu->policy, pcpu->freq_table,
 261                                             freqmax - 1, CPUFREQ_RELATION_H,
 262                                             &index))
 263                                         break;
 264                                 freq = pcpu->freq_table[index].frequency;
 265
 266                                 if (freq == freqmin) {
 267                                         /*
 268                                          * The first frequency below freqmax
 269                                          * has already been found to be too
 270                                          * low.  freqmax is the lowest speed
 271                                          * we found that is fast enough.
 272                                          */
 273                                         freq = freqmax;
 274                                         break;
 275                                 }
 276                         }
 277                 } else if (freq < prevfreq) {
 278                         /* The previous frequency is high enough. */
 279                         freqmax = prevfreq;
 280
 281                         if (freq <= freqmin) {
 282                                 /*
 283                                  * Find the lowest frequency that is higher
 284                                  * than freqmin.
 285                                  */
 286                                 if (cpufreq_frequency_table_target(
 287                                             pcpu->policy, pcpu->freq_table,
 288                                             freqmin + 1, CPUFREQ_RELATION_L,
 289                                             &index))
 290                                         break;
 291                                 freq = pcpu->freq_table[index].frequency;
 292
 293                                 /*
 294                                  * If freqmax is the first frequency above
 295                                  * freqmin then we have already found that
 296                                  * this speed is fast enough.
 297                                  */
 298                                 if (freq == freqmax)
 299                                         break;
 300                         }
 301                 }
 302
 303                 /* If same frequency chosen as previous then done. */
 304         } while (freq != prevfreq);
 305
 306         return freq;
 307 }
 308
 309 static u64 update_load(int cpu)
 310 {
 311         struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
 312         struct cpufreq_interactive_tunables *tunables =
 313                 pcpu->policy->governor_data;
 314         u64 now;
 315         u64 now_idle;
 316         unsigned int delta_idle;
 317         unsigned int delta_time;
 318         u64 active_time;
 319
 320         now_idle = get_cpu_idle_time(cpu, &now, tunables->io_is_busy);
 321         delta_idle = (unsigned int)(now_idle - pcpu->time_in_idle);
 322         delta_time = (unsigned int)(now - pcpu->time_in_idle_timestamp);
 323
 324         if (delta_time <= delta_idle)
 325                 active_time = 0;
 326         else
 327                 active_time = delta_time - delta_idle;
 328
 329         pcpu->cputime_speedadj += active_time * pcpu->policy->cur;
 330
 331         pcpu->time_in_idle = now_idle;
 332         pcpu->time_in_idle_timestamp = now;
 333         return now;
 334 }
 335
 336 static void cpufreq_interactive_timer(unsigned long data)
 337 {
 338         u64 now;
 339         unsigned int delta_time;
 340         u64 cputime_speedadj;
 341         int cpu_load;
 342         struct cpufreq_interactive_cpuinfo *pcpu =
 343                 &per_cpu(cpuinfo, data);
 344         struct cpufreq_interactive_tunables *tunables =
 345                 pcpu->policy->governor_data;
 346         unsigned int new_freq;
 347         unsigned int loadadjfreq;
 348         unsigned int index;
 349         unsigned long flags;
 350         u64 max_fvtime;
 351
 352         if (!down_read_trylock(&pcpu->enable_sem))
 353                 return;
 354         if (!pcpu->governor_enabled)
 355                 goto exit;
 356
 357         spin_lock_irqsave(&pcpu->load_lock, flags);
 358         now = update_load(data);
 359         delta_time = (unsigned int)(now - pcpu->cputime_speedadj_timestamp);
 360         cputime_speedadj = pcpu->cputime_speedadj;
 361         spin_unlock_irqrestore(&pcpu->load_lock, flags);
 362
 363         if (WARN_ON_ONCE(!delta_time))
 364                 goto rearm;
 365
 366         spin_lock_irqsave(&pcpu->target_freq_lock, flags);
 367         do_div(cputime_speedadj, delta_time);
 368         loadadjfreq = (unsigned int)cputime_speedadj * 100;
 369         cpu_load = loadadjfreq / pcpu->target_freq;
 370         tunables->boosted = tunables->boost_val || now < tunables->boostpulse_endtime;
 371
 372         if (cpu_load >= tunables->go_hispeed_load || tunables->boosted) {
 373                 if (pcpu->policy->cur < tunables->hispeed_freq) {
 374                         new_freq = tunables->hispeed_freq;
 375                 } else {
 376                         new_freq = choose_freq(pcpu, loadadjfreq);
 377
 378                         if (new_freq < tunables->hispeed_freq)
 379                                 new_freq = tunables->hispeed_freq;
 380                 }
 381         } else {
 382                 new_freq = choose_freq(pcpu, loadadjfreq);
 383                 if (new_freq > tunables->hispeed_freq &&
 384                                 pcpu->policy->cur < tunables->hispeed_freq)
 385                         new_freq = tunables->hispeed_freq;
 386         }
 387
 388         if (pcpu->policy->cur >= tunables->hispeed_freq &&
 389             new_freq > pcpu->policy->cur &&
 390             now - pcpu->pol_hispeed_val_time <
 391             freq_to_above_hispeed_delay(tunables, pcpu->policy->cur)) {
 392                 trace_cpufreq_interactive_notyet(
 393                         data, cpu_load, pcpu->target_freq,
 394                         pcpu->policy->cur, new_freq);
 395                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 396                 goto rearm;
 397         }
 398
 399         pcpu->loc_hispeed_val_time = now;
 400
 401         if (cpufreq_frequency_table_target(pcpu->policy, pcpu->freq_table,
 402                                            new_freq, CPUFREQ_RELATION_L,
 403                                            &index)) {
 404                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 405                 goto rearm;
 406         }
 407
 408         new_freq = pcpu->freq_table[index].frequency;
 409
 410         /*
 411          * Do not scale below floor_freq unless we have been at or above the
 412          * floor frequency for the minimum sample time since last validated.
 413          */
 414         max_fvtime = max(pcpu->pol_floor_val_time, pcpu->loc_floor_val_time);
 415         if (new_freq < pcpu->floor_freq &&
 416             pcpu->target_freq >= pcpu->policy->cur) {
 417                 if (now - max_fvtime < 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                 if (pcpu->target_freq >= pcpu->policy->cur ||
 437                     new_freq >= pcpu->policy->cur)
 438                         pcpu->loc_floor_val_time = now;
 439         }
 440
 441         if (pcpu->target_freq == new_freq &&
 442                         pcpu->target_freq <= pcpu->policy->cur) {
 443                 trace_cpufreq_interactive_already(
 444                         data, cpu_load, pcpu->target_freq,
 445                         pcpu->policy->cur, new_freq);
 446                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 447                 goto rearm_if_notmax;
 448         }
 449
 450         trace_cpufreq_interactive_target(data, cpu_load, pcpu->target_freq,
 451                                          pcpu->policy->cur, new_freq);
 452
 453         pcpu->target_freq = new_freq;
 454         spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
 455         spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 456         cpumask_set_cpu(data, &speedchange_cpumask);
 457         spin_unlock_irqrestore(&speedchange_cpumask_lock, flags);
 458         wake_up_process(speedchange_task);
 459
 460 rearm_if_notmax:
 461         /*
 462          * Already set max speed and don't see a need to change that,
 463          * wait until next idle to re-evaluate, don't need timer.
 464          */
 465         if (pcpu->target_freq == pcpu->policy->max)
 466                 goto exit;
 467
 468 rearm:
 469         if (!timer_pending(&pcpu->cpu_timer))
 470                 cpufreq_interactive_timer_resched(pcpu);
 471
 472 exit:
 473         up_read(&pcpu->enable_sem);
 474         return;
 475 }
 476
 477 static void cpufreq_interactive_idle_start(void)
 478 {
 479         struct cpufreq_interactive_cpuinfo *pcpu =
 480                 &per_cpu(cpuinfo, smp_processor_id());
 481         int pending;
 482
 483         if (!down_read_trylock(&pcpu->enable_sem))
 484                 return;
 485         if (!pcpu->governor_enabled) {
 486                 up_read(&pcpu->enable_sem);
 487                 return;
 488         }
 489
 490         pending = timer_pending(&pcpu->cpu_timer);
 491
 492         if (pcpu->target_freq != pcpu->policy->min) {
 493                 /*
 494                  * Entering idle while not at lowest speed.  On some
 495                  * platforms this can hold the other CPU(s) at that speed
 496                  * even though the CPU is idle. Set a timer to re-evaluate
 497                  * speed so this idle CPU doesn't hold the other CPUs above
 498                  * min indefinitely.  This should probably be a quirk of
 499                  * the CPUFreq driver.
 500                  */
 501                 if (!pending)
 502                         cpufreq_interactive_timer_resched(pcpu);
 503         }
 504
 505         up_read(&pcpu->enable_sem);
 506 }
 507
 508 static void cpufreq_interactive_idle_end(void)
 509 {
 510         struct cpufreq_interactive_cpuinfo *pcpu =
 511                 &per_cpu(cpuinfo, smp_processor_id());
 512
 513         if (!down_read_trylock(&pcpu->enable_sem))
 514                 return;
 515         if (!pcpu->governor_enabled) {
 516                 up_read(&pcpu->enable_sem);
 517                 return;
 518         }
 519
 520         /* Arm the timer for 1-2 ticks later if not already. */
 521         if (!timer_pending(&pcpu->cpu_timer)) {
 522                 cpufreq_interactive_timer_resched(pcpu);
 523         } else if (time_after_eq(jiffies, pcpu->cpu_timer.expires)) {
 524                 del_timer(&pcpu->cpu_timer);
 525                 del_timer(&pcpu->cpu_slack_timer);
 526                 cpufreq_interactive_timer(smp_processor_id());
 527         }
 528
 529         up_read(&pcpu->enable_sem);
 530 }
 531
 532 static int cpufreq_interactive_speedchange_task(void *data)
 533 {
 534         unsigned int cpu;
 535         cpumask_t tmp_mask;
 536         unsigned long flags;
 537         struct cpufreq_interactive_cpuinfo *pcpu;
 538
 539         while (1) {
 540                 set_current_state(TASK_INTERRUPTIBLE);
 541                 spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 542
 543                 if (cpumask_empty(&speedchange_cpumask)) {
 544                         spin_unlock_irqrestore(&speedchange_cpumask_lock,
 545                                                flags);
 546                         schedule();
 547
 548                         if (kthread_should_stop())
 549                                 break;
 550
 551                         spin_lock_irqsave(&speedchange_cpumask_lock, flags);
 552                 }
 553
 554                 set_current_state(TASK_RUNNING);
 555                 tmp_mask = speedchange_cpumask;
 556                 cpumask_clear(&speedchange_cpumask);
 557                 spin_unlock_irqrestore(&speedchange_cpumask_lock, flags);
 558
 559                 for_each_cpu(cpu, &tmp_mask) {
 560                         unsigned int j;
 561                         unsigned int max_freq = 0;
 562                         struct cpufreq_interactive_cpuinfo *pjcpu;
 563                         u64 hvt = ~0ULL, fvt = 0;
 564
 565                         pcpu = &per_cpu(cpuinfo, cpu);
 566                         if (!down_read_trylock(&pcpu->enable_sem))
 567                                 continue;
 568                         if (!pcpu->governor_enabled) {
 569                                 up_read(&pcpu->enable_sem);
 570                                 continue;
 571                         }
 572
 573                         for_each_cpu(j, pcpu->policy->cpus) {
 574                                 pjcpu = &per_cpu(cpuinfo, j);
 575
 576                                 fvt = max(fvt, pjcpu->loc_floor_val_time);
 577                                 if (pjcpu->target_freq > max_freq) {
 578                                         max_freq = pjcpu->target_freq;
 579                                         hvt = pjcpu->loc_hispeed_val_time;
 580                                 } else if (pjcpu->target_freq == max_freq) {
 581                                         hvt = min(hvt, pjcpu->loc_hispeed_val_time);
 582                                 }
 583                         }
 584                         for_each_cpu(j, pcpu->policy->cpus) {
 585                                 pjcpu = &per_cpu(cpuinfo, j);
 586                                 pjcpu->pol_floor_val_time = fvt;
 587                         }
 588
 589                         if (max_freq != pcpu->policy->cur) {
 590                                 __cpufreq_driver_target(pcpu->policy,
 591                                                         max_freq,
 592                                                         CPUFREQ_RELATION_H);
 593                                 for_each_cpu(j, pcpu->policy->cpus) {
 594                                         pjcpu = &per_cpu(cpuinfo, j);
 595                                         pjcpu->pol_hispeed_val_time = hvt;
 596                                 }
 597                         }
 598                         trace_cpufreq_interactive_setspeed(cpu,
 599                                                      pcpu->target_freq,
 600                                                      pcpu->policy->cur);
 601
 602                         up_read(&pcpu->enable_sem);
 603                 }
 604         }
 605
 606         return 0;
 607 }
 608
 609 static void cpufreq_interactive_boost(struct cpufreq_interactive_tunables *tunables)
 610 {
 611         int i;
 612         int anyboost = 0;
 613         unsigned long flags[2];
 614         struct cpufreq_interactive_cpuinfo *pcpu;
 615
 616         tunables->boosted = true;
 617
 618         spin_lock_irqsave(&speedchange_cpumask_lock, flags[0]);
 619
 620         for_each_online_cpu(i) {
 621                 pcpu = &per_cpu(cpuinfo, i);
 622                 if (tunables != pcpu->policy->governor_data)
 623                         continue;
 624
 625                 spin_lock_irqsave(&pcpu->target_freq_lock, flags[1]);
 626                 if (pcpu->target_freq < tunables->hispeed_freq) {
 627                         pcpu->target_freq = tunables->hispeed_freq;
 628                         cpumask_set_cpu(i, &speedchange_cpumask);
 629                         pcpu->pol_hispeed_val_time =
 630                                 ktime_to_us(ktime_get());
 631                         anyboost = 1;
 632                 }
 633                 spin_unlock_irqrestore(&pcpu->target_freq_lock, flags[1]);
 634         }
 635
 636         spin_unlock_irqrestore(&speedchange_cpumask_lock, flags[0]);
 637
 638         if (anyboost)
 639                 wake_up_process(speedchange_task);
 640 }
 641
 642 static int cpufreq_interactive_notifier(
 643         struct notifier_block *nb, unsigned long val, void *data)
 644 {
 645         struct cpufreq_freqs *freq = data;
 646         struct cpufreq_interactive_cpuinfo *pcpu;
 647         int cpu;
 648         unsigned long flags;
 649
 650         if (val == CPUFREQ_POSTCHANGE) {
 651                 pcpu = &per_cpu(cpuinfo, freq->cpu);
 652                 if (!down_read_trylock(&pcpu->enable_sem))
 653                         return 0;
 654                 if (!pcpu->governor_enabled) {
 655                         up_read(&pcpu->enable_sem);
 656                         return 0;
 657                 }
 658
 659                 for_each_cpu(cpu, pcpu->policy->cpus) {
 660                         struct cpufreq_interactive_cpuinfo *pjcpu =
 661                                 &per_cpu(cpuinfo, cpu);
 662                         if (cpu != freq->cpu) {
 663                                 if (!down_read_trylock(&pjcpu->enable_sem))
 664                                         continue;
 665                                 if (!pjcpu->governor_enabled) {
 666                                         up_read(&pjcpu->enable_sem);
 667                                         continue;
 668                                 }
 669                         }
 670                         spin_lock_irqsave(&pjcpu->load_lock, flags);
 671                         update_load(cpu);
 672                         spin_unlock_irqrestore(&pjcpu->load_lock, flags);
 673                         if (cpu != freq->cpu)
 674                                 up_read(&pjcpu->enable_sem);
 675                 }
 676
 677                 up_read(&pcpu->enable_sem);
 678         }
 679         return 0;
 680 }
 681
 682 static struct notifier_block cpufreq_notifier_block = {
 683         .notifier_call = cpufreq_interactive_notifier,
 684 };
 685
 686 static unsigned int *get_tokenized_data(const char *buf, int *num_tokens)
 687 {
 688         const char *cp;
 689         int i;
 690         int ntokens = 1;
 691         unsigned int *tokenized_data;
 692         int err = -EINVAL;
 693
 694         cp = buf;
 695         while ((cp = strpbrk(cp + 1, " :")))
 696                 ntokens++;
 697
 698         if (!(ntokens & 0x1))
 699                 goto err;
 700
 701         tokenized_data = kmalloc(ntokens * sizeof(unsigned int), GFP_KERNEL);
 702         if (!tokenized_data) {
 703                 err = -ENOMEM;
 704                 goto err;
 705         }
 706
 707         cp = buf;
 708         i = 0;
 709         while (i < ntokens) {
 710                 if (sscanf(cp, "%u", &tokenized_data[i++]) != 1)
 711                         goto err_kfree;
 712
 713                 cp = strpbrk(cp, " :");
 714                 if (!cp)
 715                         break;
 716                 cp++;
 717         }
 718
 719         if (i != ntokens)
 720                 goto err_kfree;
 721
 722         *num_tokens = ntokens;
 723         return tokenized_data;
 724
 725 err_kfree:
 726         kfree(tokenized_data);
 727 err:
 728         return ERR_PTR(err);
 729 }
 730
 731 static ssize_t show_target_loads(
 732         struct cpufreq_interactive_tunables *tunables,
 733         char *buf)
 734 {
 735         int i;
 736         ssize_t ret = 0;
 737         unsigned long flags;
 738
 739         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 740
 741         for (i = 0; i < tunables->ntarget_loads; i++)
 742                 ret += sprintf(buf + ret, "%u%s", tunables->target_loads[i],
 743                                i & 0x1 ? ":" : " ");
 744
 745         sprintf(buf + ret - 1, "\n");
 746         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 747         return ret;
 748 }
 749
 750 static ssize_t store_target_loads(
 751         struct cpufreq_interactive_tunables *tunables,
 752         const char *buf, size_t count)
 753 {
 754         int ntokens;
 755         unsigned int *new_target_loads = NULL;
 756         unsigned long flags;
 757
 758         new_target_loads = get_tokenized_data(buf, &ntokens);
 759         if (IS_ERR(new_target_loads))
 760                 return PTR_RET(new_target_loads);
 761
 762         spin_lock_irqsave(&tunables->target_loads_lock, flags);
 763         if (tunables->target_loads != default_target_loads)
 764                 kfree(tunables->target_loads);
 765         tunables->target_loads = new_target_loads;
 766         tunables->ntarget_loads = ntokens;
 767         spin_unlock_irqrestore(&tunables->target_loads_lock, flags);
 768         return count;
 769 }
 770
 771 static ssize_t show_above_hispeed_delay(
 772         struct cpufreq_interactive_tunables *tunables, char *buf)
 773 {
 774         int i;
 775         ssize_t ret = 0;
 776         unsigned long flags;
 777
 778         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 779
 780         for (i = 0; i < tunables->nabove_hispeed_delay; i++)
 781                 ret += sprintf(buf + ret, "%u%s",
 782                                tunables->above_hispeed_delay[i],
 783                                i & 0x1 ? ":" : " ");
 784
 785         sprintf(buf + ret - 1, "\n");
 786         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 787         return ret;
 788 }
 789
 790 static ssize_t store_above_hispeed_delay(
 791         struct cpufreq_interactive_tunables *tunables,
 792         const char *buf, size_t count)
 793 {
 794         int ntokens;
 795         unsigned int *new_above_hispeed_delay = NULL;
 796         unsigned long flags;
 797
 798         new_above_hispeed_delay = get_tokenized_data(buf, &ntokens);
 799         if (IS_ERR(new_above_hispeed_delay))
 800                 return PTR_RET(new_above_hispeed_delay);
 801
 802         spin_lock_irqsave(&tunables->above_hispeed_delay_lock, flags);
 803         if (tunables->above_hispeed_delay != default_above_hispeed_delay)
 804                 kfree(tunables->above_hispeed_delay);
 805         tunables->above_hispeed_delay = new_above_hispeed_delay;
 806         tunables->nabove_hispeed_delay = ntokens;
 807         spin_unlock_irqrestore(&tunables->above_hispeed_delay_lock, flags);
 808         return count;
 809
 810 }
 811
 812 static ssize_t show_hispeed_freq(struct cpufreq_interactive_tunables *tunables,
 813                 char *buf)
 814 {
 815         return sprintf(buf, "%u\n", tunables->hispeed_freq);
 816 }
 817
 818 static ssize_t store_hispeed_freq(struct cpufreq_interactive_tunables *tunables,
 819                 const char *buf, size_t count)
 820 {
 821         int ret;
 822         long unsigned int val;
 823
 824         ret = strict_strtoul(buf, 0, &val);
 825         if (ret < 0)
 826                 return ret;
 827         tunables->hispeed_freq = val;
 828         return count;
 829 }
 830
 831 static ssize_t show_go_hispeed_load(struct cpufreq_interactive_tunables
 832                 *tunables, char *buf)
 833 {
 834         return sprintf(buf, "%lu\n", tunables->go_hispeed_load);
 835 }
 836
 837 static ssize_t store_go_hispeed_load(struct cpufreq_interactive_tunables
 838                 *tunables, const char *buf, size_t count)
 839 {
 840         int ret;
 841         unsigned long val;
 842
 843         ret = strict_strtoul(buf, 0, &val);
 844         if (ret < 0)
 845                 return ret;
 846         tunables->go_hispeed_load = val;
 847         return count;
 848 }
 849
 850 static ssize_t show_min_sample_time(struct cpufreq_interactive_tunables
 851                 *tunables, char *buf)
 852 {
 853         return sprintf(buf, "%lu\n", tunables->min_sample_time);
 854 }
 855
 856 static ssize_t store_min_sample_time(struct cpufreq_interactive_tunables
 857                 *tunables, const char *buf, size_t count)
 858 {
 859         int ret;
 860         unsigned long val;
 861
 862         ret = strict_strtoul(buf, 0, &val);
 863         if (ret < 0)
 864                 return ret;
 865         tunables->min_sample_time = val;
 866         return count;
 867 }
 868
 869 static ssize_t show_timer_rate(struct cpufreq_interactive_tunables *tunables,
 870                 char *buf)
 871 {
 872         return sprintf(buf, "%lu\n", tunables->timer_rate);
 873 }
 874
 875 static ssize_t store_timer_rate(struct cpufreq_interactive_tunables *tunables,
 876                 const char *buf, size_t count)
 877 {
 878         int ret;
 879         unsigned long val, val_round;
 880
 881         ret = strict_strtoul(buf, 0, &val);
 882         if (ret < 0)
 883                 return ret;
 884
 885         val_round = jiffies_to_usecs(usecs_to_jiffies(val));
 886         if (val != val_round)
 887                 pr_warn("timer_rate not aligned to jiffy. Rounded up to %lu\n",
 888                         val_round);
 889
 890         tunables->timer_rate = val_round;
 891         return count;
 892 }
 893
 894 static ssize_t show_timer_slack(struct cpufreq_interactive_tunables *tunables,
 895                 char *buf)
 896 {
 897         return sprintf(buf, "%d\n", tunables->timer_slack_val);
 898 }
 899
 900 static ssize_t store_timer_slack(struct cpufreq_interactive_tunables *tunables,
 901                 const char *buf, size_t count)
 902 {
 903         int ret;
 904         unsigned long val;
 905
 906         ret = kstrtol(buf, 10, &val);
 907         if (ret < 0)
 908                 return ret;
 909
 910         tunables->timer_slack_val = val;
 911         return count;
 912 }
 913
 914 static ssize_t show_boost(struct cpufreq_interactive_tunables *tunables,
 915                           char *buf)
 916 {
 917         return sprintf(buf, "%d\n", tunables->boost_val);
 918 }
 919
 920 static ssize_t store_boost(struct cpufreq_interactive_tunables *tunables,
 921                            const char *buf, size_t count)
 922 {
 923         int ret;
 924         unsigned long val;
 925
 926         ret = kstrtoul(buf, 0, &val);
 927         if (ret < 0)
 928                 return ret;
 929
 930         tunables->boost_val = val;
 931
 932         if (tunables->boost_val) {
 933                 trace_cpufreq_interactive_boost("on");
 934                 if (!tunables->boosted)
 935                         cpufreq_interactive_boost(tunables);
 936         } else {
 937                 tunables->boostpulse_endtime = ktime_to_us(ktime_get());
 938                 trace_cpufreq_interactive_unboost("off");
 939         }
 940
 941         return count;
 942 }
 943
 944 static ssize_t store_boostpulse(struct cpufreq_interactive_tunables *tunables,
 945                                 const char *buf, size_t count)
 946 {
 947         int ret;
 948         unsigned long val;
 949
 950         ret = kstrtoul(buf, 0, &val);
 951         if (ret < 0)
 952                 return ret;
 953
 954         tunables->boostpulse_endtime = ktime_to_us(ktime_get()) +
 955                 tunables->boostpulse_duration_val;
 956         trace_cpufreq_interactive_boost("pulse");
 957         if (!tunables->boosted)
 958                 cpufreq_interactive_boost(tunables);
 959         return count;
 960 }
 961
 962 static ssize_t show_boostpulse_duration(struct cpufreq_interactive_tunables
 963                 *tunables, char *buf)
 964 {
 965         return sprintf(buf, "%d\n", tunables->boostpulse_duration_val);
 966 }
 967
 968 static ssize_t store_boostpulse_duration(struct cpufreq_interactive_tunables
 969                 *tunables, const char *buf, size_t count)
 970 {
 971         int ret;
 972         unsigned long val;
 973
 974         ret = kstrtoul(buf, 0, &val);
 975         if (ret < 0)
 976                 return ret;
 977
 978         tunables->boostpulse_duration_val = val;
 979         return count;
 980 }
 981
 982 static ssize_t show_io_is_busy(struct cpufreq_interactive_tunables *tunables,
 983                 char *buf)
 984 {
 985         return sprintf(buf, "%u\n", tunables->io_is_busy);
 986 }
 987
 988 static ssize_t store_io_is_busy(struct cpufreq_interactive_tunables *tunables,
 989                 const char *buf, size_t count)
 990 {
 991         int ret;
 992         unsigned long val;
 993
 994         ret = kstrtoul(buf, 0, &val);
 995         if (ret < 0)
 996                 return ret;
 997         tunables->io_is_busy = val;
 998         return count;
 999 }
1000
1001 /*
1002  * Create show/store routines
1003  * - sys: One governor instance for complete SYSTEM
1004  * - pol: One governor instance per struct cpufreq_policy
1005  */
1006 #define show_gov_pol_sys(file_name)                                     \
1007 static ssize_t show_##file_name##_gov_sys                               \
1008 (struct kobject *kobj, struct attribute *attr, char *buf)               \
1009 {                                                                       \
1010         return show_##file_name(common_tunables, buf);                  \
1011 }                                                                       \
1012                                                                         \
1013 static ssize_t show_##file_name##_gov_pol                               \
1014 (struct cpufreq_policy *policy, char *buf)                              \
1015 {                                                                       \
1016         return show_##file_name(policy->governor_data, buf);            \
1017 }
1018
1019 #define store_gov_pol_sys(file_name)                                    \
1020 static ssize_t store_##file_name##_gov_sys                              \
1021 (struct kobject *kobj, struct attribute *attr, const char *buf,         \
1022         size_t count)                                                   \
1023 {                                                                       \
1024         return store_##file_name(common_tunables, buf, count);          \
1025 }                                                                       \
1026                                                                         \
1027 static ssize_t store_##file_name##_gov_pol                              \
1028 (struct cpufreq_policy *policy, const char *buf, size_t count)          \
1029 {                                                                       \
1030         return store_##file_name(policy->governor_data, buf, count);    \
1031 }
1032
1033 #define show_store_gov_pol_sys(file_name)                               \
1034 show_gov_pol_sys(file_name);                                            \
1035 store_gov_pol_sys(file_name)
1036
1037 show_store_gov_pol_sys(target_loads);
1038 show_store_gov_pol_sys(above_hispeed_delay);
1039 show_store_gov_pol_sys(hispeed_freq);
1040 show_store_gov_pol_sys(go_hispeed_load);
1041 show_store_gov_pol_sys(min_sample_time);
1042 show_store_gov_pol_sys(timer_rate);
1043 show_store_gov_pol_sys(timer_slack);
1044 show_store_gov_pol_sys(boost);
1045 store_gov_pol_sys(boostpulse);
1046 show_store_gov_pol_sys(boostpulse_duration);
1047 show_store_gov_pol_sys(io_is_busy);
1048
1049 #define gov_sys_attr_rw(_name)                                          \
1050 static struct global_attr _name##_gov_sys =                             \
1051 __ATTR(_name, 0644, show_##_name##_gov_sys, store_##_name##_gov_sys)
1052
1053 #define gov_pol_attr_rw(_name)                                          \
1054 static struct freq_attr _name##_gov_pol =                               \
1055 __ATTR(_name, 0644, show_##_name##_gov_pol, store_##_name##_gov_pol)
1056
1057 #define gov_sys_pol_attr_rw(_name)                                      \
1058         gov_sys_attr_rw(_name);                                         \
1059         gov_pol_attr_rw(_name)
1060
1061 gov_sys_pol_attr_rw(target_loads);
1062 gov_sys_pol_attr_rw(above_hispeed_delay);
1063 gov_sys_pol_attr_rw(hispeed_freq);
1064 gov_sys_pol_attr_rw(go_hispeed_load);
1065 gov_sys_pol_attr_rw(min_sample_time);
1066 gov_sys_pol_attr_rw(timer_rate);
1067 gov_sys_pol_attr_rw(timer_slack);
1068 gov_sys_pol_attr_rw(boost);
1069 gov_sys_pol_attr_rw(boostpulse_duration);
1070 gov_sys_pol_attr_rw(io_is_busy);
1071
1072 static struct global_attr boostpulse_gov_sys =
1073         __ATTR(boostpulse, 0200, NULL, store_boostpulse_gov_sys);
1074
1075 static struct freq_attr boostpulse_gov_pol =
1076         __ATTR(boostpulse, 0200, NULL, store_boostpulse_gov_pol);
1077
1078 /* One Governor instance for entire system */
1079 static struct attribute *interactive_attributes_gov_sys[] = {
1080         &target_loads_gov_sys.attr,
1081         &above_hispeed_delay_gov_sys.attr,
1082         &hispeed_freq_gov_sys.attr,
1083         &go_hispeed_load_gov_sys.attr,
1084         &min_sample_time_gov_sys.attr,
1085         &timer_rate_gov_sys.attr,
1086         &timer_slack_gov_sys.attr,
1087         &boost_gov_sys.attr,
1088         &boostpulse_gov_sys.attr,
1089         &boostpulse_duration_gov_sys.attr,
1090         &io_is_busy_gov_sys.attr,
1091         NULL,
1092 };
1093
1094 static struct attribute_group interactive_attr_group_gov_sys = {
1095         .attrs = interactive_attributes_gov_sys,
1096         .name = "interactive",
1097 };
1098
1099 /* Per policy governor instance */
1100 static struct attribute *interactive_attributes_gov_pol[] = {
1101         &target_loads_gov_pol.attr,
1102         &above_hispeed_delay_gov_pol.attr,
1103         &hispeed_freq_gov_pol.attr,
1104         &go_hispeed_load_gov_pol.attr,
1105         &min_sample_time_gov_pol.attr,
1106         &timer_rate_gov_pol.attr,
1107         &timer_slack_gov_pol.attr,
1108         &boost_gov_pol.attr,
1109         &boostpulse_gov_pol.attr,
1110         &boostpulse_duration_gov_pol.attr,
1111         &io_is_busy_gov_pol.attr,
1112         NULL,
1113 };
1114
1115 static struct attribute_group interactive_attr_group_gov_pol = {
1116         .attrs = interactive_attributes_gov_pol,
1117         .name = "interactive",
1118 };
1119
1120 static struct attribute_group *get_sysfs_attr(void)
1121 {
1122         if (have_governor_per_policy())
1123                 return &interactive_attr_group_gov_pol;
1124         else
1125                 return &interactive_attr_group_gov_sys;
1126 }
1127
1128 static int cpufreq_interactive_idle_notifier(struct notifier_block *nb,
1129                                              unsigned long val,
1130                                              void *data)
1131 {
1132         switch (val) {
1133         case IDLE_START:
1134                 cpufreq_interactive_idle_start();
1135                 break;
1136         case IDLE_END:
1137                 cpufreq_interactive_idle_end();
1138                 break;
1139         }
1140
1141         return 0;
1142 }
1143
1144 static struct notifier_block cpufreq_interactive_idle_nb = {
1145         .notifier_call = cpufreq_interactive_idle_notifier,
1146 };
1147
1148 static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
1149                 unsigned int event)
1150 {
1151         int rc;
1152         unsigned int j;
1153         struct cpufreq_interactive_cpuinfo *pcpu;
1154         struct cpufreq_frequency_table *freq_table;
1155         struct cpufreq_interactive_tunables *tunables;
1156         unsigned long flags;
1157
1158         if (have_governor_per_policy())
1159                 tunables = policy->governor_data;
1160         else
1161                 tunables = common_tunables;
1162
1163         WARN_ON(!tunables && (event != CPUFREQ_GOV_POLICY_INIT));
1164
1165         switch (event) {
1166         case CPUFREQ_GOV_POLICY_INIT:
1167                 if (have_governor_per_policy()) {
1168                         WARN_ON(tunables);
1169                 } else if (tunables) {
1170                         tunables->usage_count++;
1171                         policy->governor_data = tunables;
1172                         return 0;
1173                 }
1174
1175                 tunables = kzalloc(sizeof(*tunables), GFP_KERNEL);
1176                 if (!tunables) {
1177                         pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__);
1178                         return -ENOMEM;
1179                 }
1180
1181                 tunables->usage_count = 1;
1182                 tunables->above_hispeed_delay = default_above_hispeed_delay;
1183                 tunables->nabove_hispeed_delay =
1184                         ARRAY_SIZE(default_above_hispeed_delay);
1185                 tunables->go_hispeed_load = DEFAULT_GO_HISPEED_LOAD;
1186                 tunables->target_loads = default_target_loads;
1187                 tunables->ntarget_loads = ARRAY_SIZE(default_target_loads);
1188                 tunables->min_sample_time = DEFAULT_MIN_SAMPLE_TIME;
1189                 tunables->timer_rate = DEFAULT_TIMER_RATE;
1190                 tunables->boostpulse_duration_val = DEFAULT_MIN_SAMPLE_TIME;
1191                 tunables->timer_slack_val = DEFAULT_TIMER_SLACK;
1192
1193                 spin_lock_init(&tunables->target_loads_lock);
1194                 spin_lock_init(&tunables->above_hispeed_delay_lock);
1195
1196                 policy->governor_data = tunables;
1197                 if (!have_governor_per_policy()) {
1198                         common_tunables = tunables;
1199                         WARN_ON(cpufreq_get_global_kobject());
1200                 }
1201
1202                 rc = sysfs_create_group(get_governor_parent_kobj(policy),
1203                                 get_sysfs_attr());
1204                 if (rc) {
1205                         kfree(tunables);
1206                         policy->governor_data = NULL;
1207                         if (!have_governor_per_policy()) {
1208                                 common_tunables = NULL;
1209                                 cpufreq_put_global_kobject();
1210                         }
1211                         return rc;
1212                 }
1213
1214                 if (!policy->governor->initialized) {
1215                         idle_notifier_register(&cpufreq_interactive_idle_nb);
1216                         cpufreq_register_notifier(&cpufreq_notifier_block,
1217                                         CPUFREQ_TRANSITION_NOTIFIER);
1218                 }
1219
1220                 break;
1221
1222         case CPUFREQ_GOV_POLICY_EXIT:
1223                 if (!--tunables->usage_count) {
1224                         if (policy->governor->initialized == 1) {
1225                                 cpufreq_unregister_notifier(&cpufreq_notifier_block,
1226                                                 CPUFREQ_TRANSITION_NOTIFIER);
1227                                 idle_notifier_unregister(&cpufreq_interactive_idle_nb);
1228                         }
1229
1230                         sysfs_remove_group(get_governor_parent_kobj(policy),
1231                                         get_sysfs_attr());
1232
1233                         if (!have_governor_per_policy())
1234                                 cpufreq_put_global_kobject();
1235
1236                         kfree(tunables);
1237                         common_tunables = NULL;
1238                 }
1239
1240                 policy->governor_data = NULL;
1241                 break;
1242
1243         case CPUFREQ_GOV_START:
1244                 mutex_lock(&gov_lock);
1245
1246                 freq_table = cpufreq_frequency_get_table(policy->cpu);
1247                 if (!tunables->hispeed_freq)
1248                         tunables->hispeed_freq = policy->max;
1249
1250                 for_each_cpu(j, policy->cpus) {
1251                         pcpu = &per_cpu(cpuinfo, j);
1252                         pcpu->policy = policy;
1253                         pcpu->target_freq = policy->cur;
1254                         pcpu->freq_table = freq_table;
1255                         pcpu->floor_freq = pcpu->target_freq;
1256                         pcpu->pol_floor_val_time =
1257                                 ktime_to_us(ktime_get());
1258                         pcpu->loc_floor_val_time = pcpu->pol_floor_val_time;
1259                         pcpu->pol_hispeed_val_time = pcpu->pol_floor_val_time;
1260                         pcpu->loc_hispeed_val_time = pcpu->pol_floor_val_time;
1261                         pcpu->max_freq = policy->max;
1262                         down_write(&pcpu->enable_sem);
1263                         del_timer_sync(&pcpu->cpu_timer);
1264                         del_timer_sync(&pcpu->cpu_slack_timer);
1265                         cpufreq_interactive_timer_start(tunables, j);
1266                         pcpu->governor_enabled = 1;
1267                         up_write(&pcpu->enable_sem);
1268                 }
1269
1270                 mutex_unlock(&gov_lock);
1271                 break;
1272
1273         case CPUFREQ_GOV_STOP:
1274                 mutex_lock(&gov_lock);
1275                 for_each_cpu(j, policy->cpus) {
1276                         pcpu = &per_cpu(cpuinfo, j);
1277                         down_write(&pcpu->enable_sem);
1278                         pcpu->governor_enabled = 0;
1279                         del_timer_sync(&pcpu->cpu_timer);
1280                         del_timer_sync(&pcpu->cpu_slack_timer);
1281                         up_write(&pcpu->enable_sem);
1282                 }
1283
1284                 mutex_unlock(&gov_lock);
1285                 break;
1286
1287         case CPUFREQ_GOV_LIMITS:
1288                 if (policy->max < policy->cur)
1289                         __cpufreq_driver_target(policy,
1290                                         policy->max, CPUFREQ_RELATION_H);
1291                 else if (policy->min > policy->cur)
1292                         __cpufreq_driver_target(policy,
1293                                         policy->min, CPUFREQ_RELATION_L);
1294                 for_each_cpu(j, policy->cpus) {
1295                         pcpu = &per_cpu(cpuinfo, j);
1296
1297                         down_read(&pcpu->enable_sem);
1298                         if (pcpu->governor_enabled == 0) {
1299                                 up_read(&pcpu->enable_sem);
1300                                 continue;
1301                         }
1302
1303                         spin_lock_irqsave(&pcpu->target_freq_lock, flags);
1304                         if (policy->max < pcpu->target_freq)
1305                                 pcpu->target_freq = policy->max;
1306                         else if (policy->min > pcpu->target_freq)
1307                                 pcpu->target_freq = policy->min;
1308
1309                         spin_unlock_irqrestore(&pcpu->target_freq_lock, flags);
1310                         up_read(&pcpu->enable_sem);
1311
1312                         /* Reschedule timer only if policy->max is raised.
1313                          * Delete the timers, else the timer callback may
1314                          * return without re-arm the timer when failed
1315                          * acquire the semaphore. This race may cause timer
1316                          * stopped unexpectedly.
1317                          */
1318
1319                         if (policy->max > pcpu->max_freq) {
1320                                 down_write(&pcpu->enable_sem);
1321                                 del_timer_sync(&pcpu->cpu_timer);
1322                                 del_timer_sync(&pcpu->cpu_slack_timer);
1323                                 cpufreq_interactive_timer_start(tunables, j);
1324                                 up_write(&pcpu->enable_sem);
1325                         }
1326
1327                         pcpu->max_freq = policy->max;
1328                 }
1329                 break;
1330         }
1331         return 0;
1332 }
1333
1334 #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE
1335 static
1336 #endif
1337 struct cpufreq_governor cpufreq_gov_interactive = {
1338         .name = "interactive",
1339         .governor = cpufreq_governor_interactive,
1340         .max_transition_latency = 10000000,
1341         .owner = THIS_MODULE,
1342 };
1343
1344 static void cpufreq_interactive_nop_timer(unsigned long data)
1345 {
1346 }
1347
1348 static int __init cpufreq_interactive_init(void)
1349 {
1350         unsigned int i;
1351         struct cpufreq_interactive_cpuinfo *pcpu;
1352         struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
1353
1354         /* Initalize per-cpu timers */
1355         for_each_possible_cpu(i) {
1356                 pcpu = &per_cpu(cpuinfo, i);
1357                 init_timer_deferrable(&pcpu->cpu_timer);
1358                 pcpu->cpu_timer.function = cpufreq_interactive_timer;
1359                 pcpu->cpu_timer.data = i;
1360                 init_timer(&pcpu->cpu_slack_timer);
1361                 pcpu->cpu_slack_timer.function = cpufreq_interactive_nop_timer;
1362                 spin_lock_init(&pcpu->load_lock);
1363                 spin_lock_init(&pcpu->target_freq_lock);
1364                 init_rwsem(&pcpu->enable_sem);
1365         }
1366
1367         spin_lock_init(&speedchange_cpumask_lock);
1368         mutex_init(&gov_lock);
1369         speedchange_task =
1370                 kthread_create(cpufreq_interactive_speedchange_task, NULL,
1371                                "cfinteractive");
1372         if (IS_ERR(speedchange_task))
1373                 return PTR_ERR(speedchange_task);
1374
1375         sched_setscheduler_nocheck(speedchange_task, SCHED_FIFO, &param);
1376         get_task_struct(speedchange_task);
1377
1378         /* NB: wake up so the thread does not look hung to the freezer */
1379         wake_up_process(speedchange_task);
1380
1381         return cpufreq_register_governor(&cpufreq_gov_interactive);
1382 }
1383
1384 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE
1385 fs_initcall(cpufreq_interactive_init);
1386 #else
1387 module_init(cpufreq_interactive_init);
1388 #endif
1389
1390 static void __exit cpufreq_interactive_exit(void)
1391 {
1392         cpufreq_unregister_governor(&cpufreq_gov_interactive);
1393         kthread_stop(speedchange_task);
1394         put_task_struct(speedchange_task);
1395 }
1396
1397 module_exit(cpufreq_interactive_exit);
1398
1399 MODULE_AUTHOR("Mike Chan <mike@android.com>");
1400 MODULE_DESCRIPTION("'cpufreq_interactive' - A cpufreq governor for "
1401         "Latency sensitive workloads");
1402 MODULE_LICENSE("GPL");