Thomas Gleixner | 79bf2bb | 2007-02-16 01:28:03 -0800 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/time/tick-sched.c |
| 3 | * |
| 4 | * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de> |
| 5 | * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar |
| 6 | * Copyright(C) 2006-2007 Timesys Corp., Thomas Gleixner |
| 7 | * |
| 8 | * No idle tick implementation for low and high resolution timers |
| 9 | * |
| 10 | * Started by: Thomas Gleixner and Ingo Molnar |
| 11 | * |
| 12 | * For licencing details see kernel-base/COPYING |
| 13 | */ |
| 14 | #include <linux/cpu.h> |
| 15 | #include <linux/err.h> |
| 16 | #include <linux/hrtimer.h> |
| 17 | #include <linux/interrupt.h> |
| 18 | #include <linux/kernel_stat.h> |
| 19 | #include <linux/percpu.h> |
| 20 | #include <linux/profile.h> |
| 21 | #include <linux/sched.h> |
| 22 | #include <linux/tick.h> |
| 23 | |
| 24 | #include "tick-internal.h" |
| 25 | |
| 26 | /* |
| 27 | * Per cpu nohz control structure |
| 28 | */ |
| 29 | static DEFINE_PER_CPU(struct tick_sched, tick_cpu_sched); |
| 30 | |
| 31 | /* |
| 32 | * The time, when the last jiffy update happened. Protected by xtime_lock. |
| 33 | */ |
| 34 | static ktime_t last_jiffies_update; |
| 35 | |
Ingo Molnar | 289f480 | 2007-02-16 01:28:15 -0800 | [diff] [blame^] | 36 | struct tick_sched *tick_get_tick_sched(int cpu) |
| 37 | { |
| 38 | return &per_cpu(tick_cpu_sched, cpu); |
| 39 | } |
| 40 | |
Thomas Gleixner | 79bf2bb | 2007-02-16 01:28:03 -0800 | [diff] [blame] | 41 | /* |
| 42 | * Must be called with interrupts disabled ! |
| 43 | */ |
| 44 | static void tick_do_update_jiffies64(ktime_t now) |
| 45 | { |
| 46 | unsigned long ticks = 0; |
| 47 | ktime_t delta; |
| 48 | |
| 49 | /* Reevalute with xtime_lock held */ |
| 50 | write_seqlock(&xtime_lock); |
| 51 | |
| 52 | delta = ktime_sub(now, last_jiffies_update); |
| 53 | if (delta.tv64 >= tick_period.tv64) { |
| 54 | |
| 55 | delta = ktime_sub(delta, tick_period); |
| 56 | last_jiffies_update = ktime_add(last_jiffies_update, |
| 57 | tick_period); |
| 58 | |
| 59 | /* Slow path for long timeouts */ |
| 60 | if (unlikely(delta.tv64 >= tick_period.tv64)) { |
| 61 | s64 incr = ktime_to_ns(tick_period); |
| 62 | |
| 63 | ticks = ktime_divns(delta, incr); |
| 64 | |
| 65 | last_jiffies_update = ktime_add_ns(last_jiffies_update, |
| 66 | incr * ticks); |
| 67 | } |
| 68 | do_timer(++ticks); |
| 69 | } |
| 70 | write_sequnlock(&xtime_lock); |
| 71 | } |
| 72 | |
| 73 | /* |
| 74 | * Initialize and return retrieve the jiffies update. |
| 75 | */ |
| 76 | static ktime_t tick_init_jiffy_update(void) |
| 77 | { |
| 78 | ktime_t period; |
| 79 | |
| 80 | write_seqlock(&xtime_lock); |
| 81 | /* Did we start the jiffies update yet ? */ |
| 82 | if (last_jiffies_update.tv64 == 0) |
| 83 | last_jiffies_update = tick_next_period; |
| 84 | period = last_jiffies_update; |
| 85 | write_sequnlock(&xtime_lock); |
| 86 | return period; |
| 87 | } |
| 88 | |
| 89 | /* |
| 90 | * NOHZ - aka dynamic tick functionality |
| 91 | */ |
| 92 | #ifdef CONFIG_NO_HZ |
| 93 | /* |
| 94 | * NO HZ enabled ? |
| 95 | */ |
| 96 | static int tick_nohz_enabled __read_mostly = 1; |
| 97 | |
| 98 | /* |
| 99 | * Enable / Disable tickless mode |
| 100 | */ |
| 101 | static int __init setup_tick_nohz(char *str) |
| 102 | { |
| 103 | if (!strcmp(str, "off")) |
| 104 | tick_nohz_enabled = 0; |
| 105 | else if (!strcmp(str, "on")) |
| 106 | tick_nohz_enabled = 1; |
| 107 | else |
| 108 | return 0; |
| 109 | return 1; |
| 110 | } |
| 111 | |
| 112 | __setup("nohz=", setup_tick_nohz); |
| 113 | |
| 114 | /** |
| 115 | * tick_nohz_update_jiffies - update jiffies when idle was interrupted |
| 116 | * |
| 117 | * Called from interrupt entry when the CPU was idle |
| 118 | * |
| 119 | * In case the sched_tick was stopped on this CPU, we have to check if jiffies |
| 120 | * must be updated. Otherwise an interrupt handler could use a stale jiffy |
| 121 | * value. We do this unconditionally on any cpu, as we don't know whether the |
| 122 | * cpu, which has the update task assigned is in a long sleep. |
| 123 | */ |
| 124 | void tick_nohz_update_jiffies(void) |
| 125 | { |
| 126 | int cpu = smp_processor_id(); |
| 127 | struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); |
| 128 | unsigned long flags; |
| 129 | ktime_t now; |
| 130 | |
| 131 | if (!ts->tick_stopped) |
| 132 | return; |
| 133 | |
| 134 | cpu_clear(cpu, nohz_cpu_mask); |
| 135 | now = ktime_get(); |
| 136 | |
| 137 | local_irq_save(flags); |
| 138 | tick_do_update_jiffies64(now); |
| 139 | local_irq_restore(flags); |
| 140 | } |
| 141 | |
| 142 | /** |
| 143 | * tick_nohz_stop_sched_tick - stop the idle tick from the idle task |
| 144 | * |
| 145 | * When the next event is more than a tick into the future, stop the idle tick |
| 146 | * Called either from the idle loop or from irq_exit() when an idle period was |
| 147 | * just interrupted by an interrupt which did not cause a reschedule. |
| 148 | */ |
| 149 | void tick_nohz_stop_sched_tick(void) |
| 150 | { |
| 151 | unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags; |
| 152 | struct tick_sched *ts; |
| 153 | ktime_t last_update, expires, now, delta; |
| 154 | int cpu; |
| 155 | |
| 156 | local_irq_save(flags); |
| 157 | |
| 158 | cpu = smp_processor_id(); |
| 159 | ts = &per_cpu(tick_cpu_sched, cpu); |
| 160 | |
| 161 | if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE)) |
| 162 | goto end; |
| 163 | |
| 164 | if (need_resched()) |
| 165 | goto end; |
| 166 | |
| 167 | cpu = smp_processor_id(); |
| 168 | BUG_ON(local_softirq_pending()); |
| 169 | |
| 170 | now = ktime_get(); |
| 171 | /* |
| 172 | * When called from irq_exit we need to account the idle sleep time |
| 173 | * correctly. |
| 174 | */ |
| 175 | if (ts->tick_stopped) { |
| 176 | delta = ktime_sub(now, ts->idle_entrytime); |
| 177 | ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); |
| 178 | } |
| 179 | |
| 180 | ts->idle_entrytime = now; |
| 181 | ts->idle_calls++; |
| 182 | |
| 183 | /* Read jiffies and the time when jiffies were updated last */ |
| 184 | do { |
| 185 | seq = read_seqbegin(&xtime_lock); |
| 186 | last_update = last_jiffies_update; |
| 187 | last_jiffies = jiffies; |
| 188 | } while (read_seqretry(&xtime_lock, seq)); |
| 189 | |
| 190 | /* Get the next timer wheel timer */ |
| 191 | next_jiffies = get_next_timer_interrupt(last_jiffies); |
| 192 | delta_jiffies = next_jiffies - last_jiffies; |
| 193 | |
| 194 | /* |
| 195 | * Do not stop the tick, if we are only one off |
| 196 | * or if the cpu is required for rcu |
| 197 | */ |
| 198 | if (!ts->tick_stopped && (delta_jiffies == 1 || rcu_needs_cpu(cpu))) |
| 199 | goto out; |
| 200 | |
| 201 | /* Schedule the tick, if we are at least one jiffie off */ |
| 202 | if ((long)delta_jiffies >= 1) { |
| 203 | |
| 204 | if (rcu_needs_cpu(cpu)) |
| 205 | delta_jiffies = 1; |
| 206 | else |
| 207 | cpu_set(cpu, nohz_cpu_mask); |
| 208 | /* |
| 209 | * nohz_stop_sched_tick can be called several times before |
| 210 | * the nohz_restart_sched_tick is called. This happens when |
| 211 | * interrupts arrive which do not cause a reschedule. In the |
| 212 | * first call we save the current tick time, so we can restart |
| 213 | * the scheduler tick in nohz_restart_sched_tick. |
| 214 | */ |
| 215 | if (!ts->tick_stopped) { |
| 216 | ts->idle_tick = ts->sched_timer.expires; |
| 217 | ts->tick_stopped = 1; |
| 218 | ts->idle_jiffies = last_jiffies; |
| 219 | } |
| 220 | /* |
| 221 | * calculate the expiry time for the next timer wheel |
| 222 | * timer |
| 223 | */ |
| 224 | expires = ktime_add_ns(last_update, tick_period.tv64 * |
| 225 | delta_jiffies); |
| 226 | ts->idle_expires = expires; |
| 227 | ts->idle_sleeps++; |
| 228 | |
| 229 | if (ts->nohz_mode == NOHZ_MODE_HIGHRES) { |
| 230 | hrtimer_start(&ts->sched_timer, expires, |
| 231 | HRTIMER_MODE_ABS); |
| 232 | /* Check, if the timer was already in the past */ |
| 233 | if (hrtimer_active(&ts->sched_timer)) |
| 234 | goto out; |
| 235 | } else if(!tick_program_event(expires, 0)) |
| 236 | goto out; |
| 237 | /* |
| 238 | * We are past the event already. So we crossed a |
| 239 | * jiffie boundary. Update jiffies and raise the |
| 240 | * softirq. |
| 241 | */ |
| 242 | tick_do_update_jiffies64(ktime_get()); |
| 243 | cpu_clear(cpu, nohz_cpu_mask); |
| 244 | } |
| 245 | raise_softirq_irqoff(TIMER_SOFTIRQ); |
| 246 | out: |
| 247 | ts->next_jiffies = next_jiffies; |
| 248 | ts->last_jiffies = last_jiffies; |
| 249 | end: |
| 250 | local_irq_restore(flags); |
| 251 | } |
| 252 | |
| 253 | /** |
| 254 | * nohz_restart_sched_tick - restart the idle tick from the idle task |
| 255 | * |
| 256 | * Restart the idle tick when the CPU is woken up from idle |
| 257 | */ |
| 258 | void tick_nohz_restart_sched_tick(void) |
| 259 | { |
| 260 | int cpu = smp_processor_id(); |
| 261 | struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); |
| 262 | unsigned long ticks; |
| 263 | ktime_t now, delta; |
| 264 | |
| 265 | if (!ts->tick_stopped) |
| 266 | return; |
| 267 | |
| 268 | /* Update jiffies first */ |
| 269 | now = ktime_get(); |
| 270 | |
| 271 | local_irq_disable(); |
| 272 | tick_do_update_jiffies64(now); |
| 273 | cpu_clear(cpu, nohz_cpu_mask); |
| 274 | |
| 275 | /* Account the idle time */ |
| 276 | delta = ktime_sub(now, ts->idle_entrytime); |
| 277 | ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); |
| 278 | |
| 279 | /* |
| 280 | * We stopped the tick in idle. Update process times would miss the |
| 281 | * time we slept as update_process_times does only a 1 tick |
| 282 | * accounting. Enforce that this is accounted to idle ! |
| 283 | */ |
| 284 | ticks = jiffies - ts->idle_jiffies; |
| 285 | /* |
| 286 | * We might be one off. Do not randomly account a huge number of ticks! |
| 287 | */ |
| 288 | if (ticks && ticks < LONG_MAX) { |
| 289 | add_preempt_count(HARDIRQ_OFFSET); |
| 290 | account_system_time(current, HARDIRQ_OFFSET, |
| 291 | jiffies_to_cputime(ticks)); |
| 292 | sub_preempt_count(HARDIRQ_OFFSET); |
| 293 | } |
| 294 | |
| 295 | /* |
| 296 | * Cancel the scheduled timer and restore the tick |
| 297 | */ |
| 298 | ts->tick_stopped = 0; |
| 299 | hrtimer_cancel(&ts->sched_timer); |
| 300 | ts->sched_timer.expires = ts->idle_tick; |
| 301 | |
| 302 | while (1) { |
| 303 | /* Forward the time to expire in the future */ |
| 304 | hrtimer_forward(&ts->sched_timer, now, tick_period); |
| 305 | |
| 306 | if (ts->nohz_mode == NOHZ_MODE_HIGHRES) { |
| 307 | hrtimer_start(&ts->sched_timer, |
| 308 | ts->sched_timer.expires, |
| 309 | HRTIMER_MODE_ABS); |
| 310 | /* Check, if the timer was already in the past */ |
| 311 | if (hrtimer_active(&ts->sched_timer)) |
| 312 | break; |
| 313 | } else { |
| 314 | if (!tick_program_event(ts->sched_timer.expires, 0)) |
| 315 | break; |
| 316 | } |
| 317 | /* Update jiffies and reread time */ |
| 318 | tick_do_update_jiffies64(now); |
| 319 | now = ktime_get(); |
| 320 | } |
| 321 | local_irq_enable(); |
| 322 | } |
| 323 | |
| 324 | static int tick_nohz_reprogram(struct tick_sched *ts, ktime_t now) |
| 325 | { |
| 326 | hrtimer_forward(&ts->sched_timer, now, tick_period); |
| 327 | return tick_program_event(ts->sched_timer.expires, 0); |
| 328 | } |
| 329 | |
| 330 | /* |
| 331 | * The nohz low res interrupt handler |
| 332 | */ |
| 333 | static void tick_nohz_handler(struct clock_event_device *dev) |
| 334 | { |
| 335 | struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); |
| 336 | struct pt_regs *regs = get_irq_regs(); |
| 337 | ktime_t now = ktime_get(); |
| 338 | |
| 339 | dev->next_event.tv64 = KTIME_MAX; |
| 340 | |
| 341 | /* Check, if the jiffies need an update */ |
| 342 | tick_do_update_jiffies64(now); |
| 343 | |
| 344 | /* |
| 345 | * When we are idle and the tick is stopped, we have to touch |
| 346 | * the watchdog as we might not schedule for a really long |
| 347 | * time. This happens on complete idle SMP systems while |
| 348 | * waiting on the login prompt. We also increment the "start |
| 349 | * of idle" jiffy stamp so the idle accounting adjustment we |
| 350 | * do when we go busy again does not account too much ticks. |
| 351 | */ |
| 352 | if (ts->tick_stopped) { |
| 353 | touch_softlockup_watchdog(); |
| 354 | ts->idle_jiffies++; |
| 355 | } |
| 356 | |
| 357 | update_process_times(user_mode(regs)); |
| 358 | profile_tick(CPU_PROFILING); |
| 359 | |
| 360 | /* Do not restart, when we are in the idle loop */ |
| 361 | if (ts->tick_stopped) |
| 362 | return; |
| 363 | |
| 364 | while (tick_nohz_reprogram(ts, now)) { |
| 365 | now = ktime_get(); |
| 366 | tick_do_update_jiffies64(now); |
| 367 | } |
| 368 | } |
| 369 | |
| 370 | /** |
| 371 | * tick_nohz_switch_to_nohz - switch to nohz mode |
| 372 | */ |
| 373 | static void tick_nohz_switch_to_nohz(void) |
| 374 | { |
| 375 | struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); |
| 376 | ktime_t next; |
| 377 | |
| 378 | if (!tick_nohz_enabled) |
| 379 | return; |
| 380 | |
| 381 | local_irq_disable(); |
| 382 | if (tick_switch_to_oneshot(tick_nohz_handler)) { |
| 383 | local_irq_enable(); |
| 384 | return; |
| 385 | } |
| 386 | |
| 387 | ts->nohz_mode = NOHZ_MODE_LOWRES; |
| 388 | |
| 389 | /* |
| 390 | * Recycle the hrtimer in ts, so we can share the |
| 391 | * hrtimer_forward with the highres code. |
| 392 | */ |
| 393 | hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); |
| 394 | /* Get the next period */ |
| 395 | next = tick_init_jiffy_update(); |
| 396 | |
| 397 | for (;;) { |
| 398 | ts->sched_timer.expires = next; |
| 399 | if (!tick_program_event(next, 0)) |
| 400 | break; |
| 401 | next = ktime_add(next, tick_period); |
| 402 | } |
| 403 | local_irq_enable(); |
| 404 | |
| 405 | printk(KERN_INFO "Switched to NOHz mode on CPU #%d\n", |
| 406 | smp_processor_id()); |
| 407 | } |
| 408 | |
| 409 | #else |
| 410 | |
| 411 | static inline void tick_nohz_switch_to_nohz(void) { } |
| 412 | |
| 413 | #endif /* NO_HZ */ |
| 414 | |
| 415 | /* |
| 416 | * High resolution timer specific code |
| 417 | */ |
| 418 | #ifdef CONFIG_HIGH_RES_TIMERS |
| 419 | /* |
| 420 | * We rearm the timer until we get disabled by the idle code |
| 421 | * Called with interrupts disabled and timer->base->cpu_base->lock held. |
| 422 | */ |
| 423 | static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) |
| 424 | { |
| 425 | struct tick_sched *ts = |
| 426 | container_of(timer, struct tick_sched, sched_timer); |
| 427 | struct hrtimer_cpu_base *base = timer->base->cpu_base; |
| 428 | struct pt_regs *regs = get_irq_regs(); |
| 429 | ktime_t now = ktime_get(); |
| 430 | |
| 431 | /* Check, if the jiffies need an update */ |
| 432 | tick_do_update_jiffies64(now); |
| 433 | |
| 434 | /* |
| 435 | * Do not call, when we are not in irq context and have |
| 436 | * no valid regs pointer |
| 437 | */ |
| 438 | if (regs) { |
| 439 | /* |
| 440 | * When we are idle and the tick is stopped, we have to touch |
| 441 | * the watchdog as we might not schedule for a really long |
| 442 | * time. This happens on complete idle SMP systems while |
| 443 | * waiting on the login prompt. We also increment the "start of |
| 444 | * idle" jiffy stamp so the idle accounting adjustment we do |
| 445 | * when we go busy again does not account too much ticks. |
| 446 | */ |
| 447 | if (ts->tick_stopped) { |
| 448 | touch_softlockup_watchdog(); |
| 449 | ts->idle_jiffies++; |
| 450 | } |
| 451 | /* |
| 452 | * update_process_times() might take tasklist_lock, hence |
| 453 | * drop the base lock. sched-tick hrtimers are per-CPU and |
| 454 | * never accessible by userspace APIs, so this is safe to do. |
| 455 | */ |
| 456 | spin_unlock(&base->lock); |
| 457 | update_process_times(user_mode(regs)); |
| 458 | profile_tick(CPU_PROFILING); |
| 459 | spin_lock(&base->lock); |
| 460 | } |
| 461 | |
| 462 | /* Do not restart, when we are in the idle loop */ |
| 463 | if (ts->tick_stopped) |
| 464 | return HRTIMER_NORESTART; |
| 465 | |
| 466 | hrtimer_forward(timer, now, tick_period); |
| 467 | |
| 468 | return HRTIMER_RESTART; |
| 469 | } |
| 470 | |
| 471 | /** |
| 472 | * tick_setup_sched_timer - setup the tick emulation timer |
| 473 | */ |
| 474 | void tick_setup_sched_timer(void) |
| 475 | { |
| 476 | struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); |
| 477 | ktime_t now = ktime_get(); |
| 478 | |
| 479 | /* |
| 480 | * Emulate tick processing via per-CPU hrtimers: |
| 481 | */ |
| 482 | hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); |
| 483 | ts->sched_timer.function = tick_sched_timer; |
| 484 | ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; |
| 485 | |
| 486 | /* Get the next period */ |
| 487 | ts->sched_timer.expires = tick_init_jiffy_update(); |
| 488 | |
| 489 | for (;;) { |
| 490 | hrtimer_forward(&ts->sched_timer, now, tick_period); |
| 491 | hrtimer_start(&ts->sched_timer, ts->sched_timer.expires, |
| 492 | HRTIMER_MODE_ABS); |
| 493 | /* Check, if the timer was already in the past */ |
| 494 | if (hrtimer_active(&ts->sched_timer)) |
| 495 | break; |
| 496 | now = ktime_get(); |
| 497 | } |
| 498 | |
| 499 | #ifdef CONFIG_NO_HZ |
| 500 | if (tick_nohz_enabled) |
| 501 | ts->nohz_mode = NOHZ_MODE_HIGHRES; |
| 502 | #endif |
| 503 | } |
| 504 | |
| 505 | void tick_cancel_sched_timer(int cpu) |
| 506 | { |
| 507 | struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); |
| 508 | |
| 509 | if (ts->sched_timer.base) |
| 510 | hrtimer_cancel(&ts->sched_timer); |
| 511 | ts->tick_stopped = 0; |
| 512 | ts->nohz_mode = NOHZ_MODE_INACTIVE; |
| 513 | } |
| 514 | #endif /* HIGH_RES_TIMERS */ |
| 515 | |
| 516 | /** |
| 517 | * Async notification about clocksource changes |
| 518 | */ |
| 519 | void tick_clock_notify(void) |
| 520 | { |
| 521 | int cpu; |
| 522 | |
| 523 | for_each_possible_cpu(cpu) |
| 524 | set_bit(0, &per_cpu(tick_cpu_sched, cpu).check_clocks); |
| 525 | } |
| 526 | |
| 527 | /* |
| 528 | * Async notification about clock event changes |
| 529 | */ |
| 530 | void tick_oneshot_notify(void) |
| 531 | { |
| 532 | struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); |
| 533 | |
| 534 | set_bit(0, &ts->check_clocks); |
| 535 | } |
| 536 | |
| 537 | /** |
| 538 | * Check, if a change happened, which makes oneshot possible. |
| 539 | * |
| 540 | * Called cyclic from the hrtimer softirq (driven by the timer |
| 541 | * softirq) allow_nohz signals, that we can switch into low-res nohz |
| 542 | * mode, because high resolution timers are disabled (either compile |
| 543 | * or runtime). |
| 544 | */ |
| 545 | int tick_check_oneshot_change(int allow_nohz) |
| 546 | { |
| 547 | struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); |
| 548 | |
| 549 | if (!test_and_clear_bit(0, &ts->check_clocks)) |
| 550 | return 0; |
| 551 | |
| 552 | if (ts->nohz_mode != NOHZ_MODE_INACTIVE) |
| 553 | return 0; |
| 554 | |
| 555 | if (!timekeeping_is_continuous() || !tick_is_oneshot_available()) |
| 556 | return 0; |
| 557 | |
| 558 | if (!allow_nohz) |
| 559 | return 1; |
| 560 | |
| 561 | tick_nohz_switch_to_nohz(); |
| 562 | return 0; |
| 563 | } |