qemu/include/qemu/timer.h
<<
>>
Prefs
   1#ifndef QEMU_TIMER_H
   2#define QEMU_TIMER_H
   3
   4#include "qemu-common.h"
   5#include "qemu/notify.h"
   6#include "qemu/host-utils.h"
   7#include "sysemu/cpus.h"
   8
   9#define NANOSECONDS_PER_SECOND 1000000000LL
  10
  11/* timers */
  12
  13#define SCALE_MS 1000000
  14#define SCALE_US 1000
  15#define SCALE_NS 1
  16
  17/**
  18 * QEMUClockType:
  19 *
  20 * The following clock types are available:
  21 *
  22 * @QEMU_CLOCK_REALTIME: Real time clock
  23 *
  24 * The real time clock should be used only for stuff which does not
  25 * change the virtual machine state, as it is run even if the virtual
  26 * machine is stopped. The real time clock has a frequency of 1000
  27 * Hz.
  28 *
  29 * @QEMU_CLOCK_VIRTUAL: virtual clock
  30 *
  31 * The virtual clock is only run during the emulation. It is stopped
  32 * when the virtual machine is stopped. Virtual timers use a high
  33 * precision clock, usually cpu cycles (use ticks_per_sec).
  34 *
  35 * @QEMU_CLOCK_HOST: host clock
  36 *
  37 * The host clock should be use for device models that emulate accurate
  38 * real time sources. It will continue to run when the virtual machine
  39 * is suspended, and it will reflect system time changes the host may
  40 * undergo (e.g. due to NTP). The host clock has the same precision as
  41 * the virtual clock.
  42 *
  43 * @QEMU_CLOCK_VIRTUAL_RT: realtime clock used for icount warp
  44 *
  45 * Outside icount mode, this clock is the same as @QEMU_CLOCK_VIRTUAL.
  46 * In icount mode, this clock counts nanoseconds while the virtual
  47 * machine is running.  It is used to increase @QEMU_CLOCK_VIRTUAL
  48 * while the CPUs are sleeping and thus not executing instructions.
  49 */
  50
  51typedef enum {
  52    QEMU_CLOCK_REALTIME = 0,
  53    QEMU_CLOCK_VIRTUAL = 1,
  54    QEMU_CLOCK_HOST = 2,
  55    QEMU_CLOCK_VIRTUAL_RT = 3,
  56    QEMU_CLOCK_MAX
  57} QEMUClockType;
  58
  59typedef struct QEMUTimerList QEMUTimerList;
  60
  61struct QEMUTimerListGroup {
  62    QEMUTimerList *tl[QEMU_CLOCK_MAX];
  63};
  64
  65typedef void QEMUTimerCB(void *opaque);
  66typedef void QEMUTimerListNotifyCB(void *opaque);
  67
  68struct QEMUTimer {
  69    int64_t expire_time;        /* in nanoseconds */
  70    QEMUTimerList *timer_list;
  71    QEMUTimerCB *cb;
  72    void *opaque;
  73    QEMUTimer *next;
  74    int scale;
  75};
  76
  77extern QEMUTimerListGroup main_loop_tlg;
  78
  79/*
  80 * QEMUClockType
  81 */
  82
  83/*
  84 * qemu_clock_get_ns;
  85 * @type: the clock type
  86 *
  87 * Get the nanosecond value of a clock with
  88 * type @type
  89 *
  90 * Returns: the clock value in nanoseconds
  91 */
  92int64_t qemu_clock_get_ns(QEMUClockType type);
  93
  94/**
  95 * qemu_clock_get_ms;
  96 * @type: the clock type
  97 *
  98 * Get the millisecond value of a clock with
  99 * type @type
 100 *
 101 * Returns: the clock value in milliseconds
 102 */
 103static inline int64_t qemu_clock_get_ms(QEMUClockType type)
 104{
 105    return qemu_clock_get_ns(type) / SCALE_MS;
 106}
 107
 108/**
 109 * qemu_clock_get_us;
 110 * @type: the clock type
 111 *
 112 * Get the microsecond value of a clock with
 113 * type @type
 114 *
 115 * Returns: the clock value in microseconds
 116 */
 117static inline int64_t qemu_clock_get_us(QEMUClockType type)
 118{
 119    return qemu_clock_get_ns(type) / SCALE_US;
 120}
 121
 122/**
 123 * qemu_clock_has_timers:
 124 * @type: the clock type
 125 *
 126 * Determines whether a clock's default timer list
 127 * has timers attached
 128 *
 129 * Note that this function should not be used when other threads also access
 130 * the timer list.  The return value may be outdated by the time it is acted
 131 * upon.
 132 *
 133 * Returns: true if the clock's default timer list
 134 * has timers attached
 135 */
 136bool qemu_clock_has_timers(QEMUClockType type);
 137
 138/**
 139 * qemu_clock_expired:
 140 * @type: the clock type
 141 *
 142 * Determines whether a clock's default timer list
 143 * has an expired clock.
 144 *
 145 * Returns: true if the clock's default timer list has
 146 * an expired timer
 147 */
 148bool qemu_clock_expired(QEMUClockType type);
 149
 150/**
 151 * qemu_clock_use_for_deadline:
 152 * @type: the clock type
 153 *
 154 * Determine whether a clock should be used for deadline
 155 * calculations. Some clocks, for instance vm_clock with
 156 * use_icount set, do not count in nanoseconds. Such clocks
 157 * are not used for deadline calculations, and are presumed
 158 * to interrupt any poll using qemu_notify/aio_notify
 159 * etc.
 160 *
 161 * Returns: true if the clock runs in nanoseconds and
 162 * should be used for a deadline.
 163 */
 164bool qemu_clock_use_for_deadline(QEMUClockType type);
 165
 166/**
 167 * qemu_clock_deadline_ns_all:
 168 * @type: the clock type
 169 *
 170 * Calculate the deadline across all timer lists associated
 171 * with a clock (as opposed to just the default one)
 172 * in nanoseconds, or -1 if no timer is set to expire.
 173 *
 174 * Returns: time until expiry in nanoseconds or -1
 175 */
 176int64_t qemu_clock_deadline_ns_all(QEMUClockType type);
 177
 178/**
 179 * qemu_clock_get_main_loop_timerlist:
 180 * @type: the clock type
 181 *
 182 * Return the default timer list assocatiated with a clock.
 183 *
 184 * Returns: the default timer list
 185 */
 186QEMUTimerList *qemu_clock_get_main_loop_timerlist(QEMUClockType type);
 187
 188/**
 189 * qemu_clock_nofify:
 190 * @type: the clock type
 191 *
 192 * Call the notifier callback connected with the default timer
 193 * list linked to the clock, or qemu_notify() if none.
 194 */
 195void qemu_clock_notify(QEMUClockType type);
 196
 197/**
 198 * qemu_clock_enable:
 199 * @type: the clock type
 200 * @enabled: true to enable, false to disable
 201 *
 202 * Enable or disable a clock
 203 * Disabling the clock will wait for related timerlists to stop
 204 * executing qemu_run_timers.  Thus, this functions should not
 205 * be used from the callback of a timer that is based on @clock.
 206 * Doing so would cause a deadlock.
 207 *
 208 * Caller should hold BQL.
 209 */
 210void qemu_clock_enable(QEMUClockType type, bool enabled);
 211
 212/**
 213 * qemu_start_warp_timer:
 214 *
 215 * Starts a timer for virtual clock update
 216 */
 217void qemu_start_warp_timer(void);
 218
 219/**
 220 * qemu_clock_register_reset_notifier:
 221 * @type: the clock type
 222 * @notifier: the notifier function
 223 *
 224 * Register a notifier function to call when the clock
 225 * concerned is reset.
 226 */
 227void qemu_clock_register_reset_notifier(QEMUClockType type,
 228                                        Notifier *notifier);
 229
 230/**
 231 * qemu_clock_unregister_reset_notifier:
 232 * @type: the clock type
 233 * @notifier: the notifier function
 234 *
 235 * Unregister a notifier function to call when the clock
 236 * concerned is reset.
 237 */
 238void qemu_clock_unregister_reset_notifier(QEMUClockType type,
 239                                          Notifier *notifier);
 240
 241/**
 242 * qemu_clock_run_timers:
 243 * @type: clock on which to operate
 244 *
 245 * Run all the timers associated with the default timer list
 246 * of a clock.
 247 *
 248 * Returns: true if any timer ran.
 249 */
 250bool qemu_clock_run_timers(QEMUClockType type);
 251
 252/**
 253 * qemu_clock_run_all_timers:
 254 *
 255 * Run all the timers associated with the default timer list
 256 * of every clock.
 257 *
 258 * Returns: true if any timer ran.
 259 */
 260bool qemu_clock_run_all_timers(void);
 261
 262/*
 263 * QEMUTimerList
 264 */
 265
 266/**
 267 * timerlist_new:
 268 * @type: the clock type to associate with the timerlist
 269 * @cb: the callback to call on notification
 270 * @opaque: the opaque pointer to pass to the callback
 271 *
 272 * Create a new timerlist associated with the clock of
 273 * type @type.
 274 *
 275 * Returns: a pointer to the QEMUTimerList created
 276 */
 277QEMUTimerList *timerlist_new(QEMUClockType type,
 278                             QEMUTimerListNotifyCB *cb, void *opaque);
 279
 280/**
 281 * timerlist_free:
 282 * @timer_list: the timer list to free
 283 *
 284 * Frees a timer_list. It must have no active timers.
 285 */
 286void timerlist_free(QEMUTimerList *timer_list);
 287
 288/**
 289 * timerlist_has_timers:
 290 * @timer_list: the timer list to operate on
 291 *
 292 * Determine whether a timer list has active timers
 293 *
 294 * Note that this function should not be used when other threads also access
 295 * the timer list.  The return value may be outdated by the time it is acted
 296 * upon.
 297 *
 298 * Returns: true if the timer list has timers.
 299 */
 300bool timerlist_has_timers(QEMUTimerList *timer_list);
 301
 302/**
 303 * timerlist_expired:
 304 * @timer_list: the timer list to operate on
 305 *
 306 * Determine whether a timer list has any timers which
 307 * are expired.
 308 *
 309 * Returns: true if the timer list has timers which
 310 * have expired.
 311 */
 312bool timerlist_expired(QEMUTimerList *timer_list);
 313
 314/**
 315 * timerlist_deadline_ns:
 316 * @timer_list: the timer list to operate on
 317 *
 318 * Determine the deadline for a timer_list, i.e.
 319 * the number of nanoseconds until the first timer
 320 * expires. Return -1 if there are no timers.
 321 *
 322 * Returns: the number of nanoseconds until the earliest
 323 * timer expires -1 if none
 324 */
 325int64_t timerlist_deadline_ns(QEMUTimerList *timer_list);
 326
 327/**
 328 * timerlist_get_clock:
 329 * @timer_list: the timer list to operate on
 330 *
 331 * Determine the clock type associated with a timer list.
 332 *
 333 * Returns: the clock type associated with the
 334 * timer list.
 335 */
 336QEMUClockType timerlist_get_clock(QEMUTimerList *timer_list);
 337
 338/**
 339 * timerlist_run_timers:
 340 * @timer_list: the timer list to use
 341 *
 342 * Call all expired timers associated with the timer list.
 343 *
 344 * Returns: true if any timer expired
 345 */
 346bool timerlist_run_timers(QEMUTimerList *timer_list);
 347
 348/**
 349 * timerlist_notify:
 350 * @timer_list: the timer list to use
 351 *
 352 * call the notifier callback associated with the timer list.
 353 */
 354void timerlist_notify(QEMUTimerList *timer_list);
 355
 356/*
 357 * QEMUTimerListGroup
 358 */
 359
 360/**
 361 * timerlistgroup_init:
 362 * @tlg: the timer list group
 363 * @cb: the callback to call when a notify is required
 364 * @opaque: the opaque pointer to be passed to the callback.
 365 *
 366 * Initialise a timer list group. This must already be
 367 * allocated in memory and zeroed. The notifier callback is
 368 * called whenever a clock in the timer list group is
 369 * reenabled or whenever a timer associated with any timer
 370 * list is modified. If @cb is specified as null, qemu_notify()
 371 * is used instead.
 372 */
 373void timerlistgroup_init(QEMUTimerListGroup *tlg,
 374                         QEMUTimerListNotifyCB *cb, void *opaque);
 375
 376/**
 377 * timerlistgroup_deinit:
 378 * @tlg: the timer list group
 379 *
 380 * Deinitialise a timer list group. This must already be
 381 * initialised. Note the memory is not freed.
 382 */
 383void timerlistgroup_deinit(QEMUTimerListGroup *tlg);
 384
 385/**
 386 * timerlistgroup_run_timers:
 387 * @tlg: the timer list group
 388 *
 389 * Run the timers associated with a timer list group.
 390 * This will run timers on multiple clocks.
 391 *
 392 * Returns: true if any timer callback ran
 393 */
 394bool timerlistgroup_run_timers(QEMUTimerListGroup *tlg);
 395
 396/**
 397 * timerlistgroup_deadline_ns:
 398 * @tlg: the timer list group
 399 *
 400 * Determine the deadline of the soonest timer to
 401 * expire associated with any timer list linked to
 402 * the timer list group. Only clocks suitable for
 403 * deadline calculation are included.
 404 *
 405 * Returns: the deadline in nanoseconds or -1 if no
 406 * timers are to expire.
 407 */
 408int64_t timerlistgroup_deadline_ns(QEMUTimerListGroup *tlg);
 409
 410/*
 411 * QEMUTimer
 412 */
 413
 414/**
 415 * timer_init_tl:
 416 * @ts: the timer to be initialised
 417 * @timer_list: the timer list to attach the timer to
 418 * @scale: the scale value for the timer
 419 * @cb: the callback to be called when the timer expires
 420 * @opaque: the opaque pointer to be passed to the callback
 421 *
 422 * Initialise a new timer and associate it with @timer_list.
 423 * The caller is responsible for allocating the memory.
 424 *
 425 * You need not call an explicit deinit call. Simply make
 426 * sure it is not on a list with timer_del.
 427 */
 428void timer_init_tl(QEMUTimer *ts,
 429                   QEMUTimerList *timer_list, int scale,
 430                   QEMUTimerCB *cb, void *opaque);
 431
 432/**
 433 * timer_init:
 434 * @type: the clock to associate with the timer
 435 * @scale: the scale value for the timer
 436 * @cb: the callback to call when the timer expires
 437 * @opaque: the opaque pointer to pass to the callback
 438 *
 439 * Initialize a timer with the given scale on the default timer list
 440 * associated with the clock.
 441 *
 442 * You need not call an explicit deinit call. Simply make
 443 * sure it is not on a list with timer_del.
 444 */
 445static inline void timer_init(QEMUTimer *ts, QEMUClockType type, int scale,
 446                              QEMUTimerCB *cb, void *opaque)
 447{
 448    timer_init_tl(ts, main_loop_tlg.tl[type], scale, cb, opaque);
 449}
 450
 451/**
 452 * timer_init_ns:
 453 * @type: the clock to associate with the timer
 454 * @cb: the callback to call when the timer expires
 455 * @opaque: the opaque pointer to pass to the callback
 456 *
 457 * Initialize a timer with nanosecond scale on the default timer list
 458 * associated with the clock.
 459 *
 460 * You need not call an explicit deinit call. Simply make
 461 * sure it is not on a list with timer_del.
 462 */
 463static inline void timer_init_ns(QEMUTimer *ts, QEMUClockType type,
 464                                 QEMUTimerCB *cb, void *opaque)
 465{
 466    timer_init(ts, type, SCALE_NS, cb, opaque);
 467}
 468
 469/**
 470 * timer_init_us:
 471 * @type: the clock to associate with the timer
 472 * @cb: the callback to call when the timer expires
 473 * @opaque: the opaque pointer to pass to the callback
 474 *
 475 * Initialize a timer with microsecond scale on the default timer list
 476 * associated with the clock.
 477 *
 478 * You need not call an explicit deinit call. Simply make
 479 * sure it is not on a list with timer_del.
 480 */
 481static inline void timer_init_us(QEMUTimer *ts, QEMUClockType type,
 482                                 QEMUTimerCB *cb, void *opaque)
 483{
 484    timer_init(ts, type, SCALE_US, cb, opaque);
 485}
 486
 487/**
 488 * timer_init_ms:
 489 * @type: the clock to associate with the timer
 490 * @cb: the callback to call when the timer expires
 491 * @opaque: the opaque pointer to pass to the callback
 492 *
 493 * Initialize a timer with millisecond scale on the default timer list
 494 * associated with the clock.
 495 *
 496 * You need not call an explicit deinit call. Simply make
 497 * sure it is not on a list with timer_del.
 498 */
 499static inline void timer_init_ms(QEMUTimer *ts, QEMUClockType type,
 500                                 QEMUTimerCB *cb, void *opaque)
 501{
 502    timer_init(ts, type, SCALE_MS, cb, opaque);
 503}
 504
 505/**
 506 * timer_new_tl:
 507 * @timer_list: the timer list to attach the timer to
 508 * @scale: the scale value for the timer
 509 * @cb: the callback to be called when the timer expires
 510 * @opaque: the opaque pointer to be passed to the callback
 511 *
 512 * Creeate a new timer and associate it with @timer_list.
 513 * The memory is allocated by the function.
 514 *
 515 * This is not the preferred interface unless you know you
 516 * are going to call timer_free. Use timer_init instead.
 517 *
 518 * Returns: a pointer to the timer
 519 */
 520static inline QEMUTimer *timer_new_tl(QEMUTimerList *timer_list,
 521                                      int scale,
 522                                      QEMUTimerCB *cb,
 523                                      void *opaque)
 524{
 525    QEMUTimer *ts = g_malloc0(sizeof(QEMUTimer));
 526    timer_init_tl(ts, timer_list, scale, cb, opaque);
 527    return ts;
 528}
 529
 530/**
 531 * timer_new:
 532 * @type: the clock type to use
 533 * @scale: the scale value for the timer
 534 * @cb: the callback to be called when the timer expires
 535 * @opaque: the opaque pointer to be passed to the callback
 536 *
 537 * Creeate a new timer and associate it with the default
 538 * timer list for the clock type @type.
 539 *
 540 * Returns: a pointer to the timer
 541 */
 542static inline QEMUTimer *timer_new(QEMUClockType type, int scale,
 543                                   QEMUTimerCB *cb, void *opaque)
 544{
 545    return timer_new_tl(main_loop_tlg.tl[type], scale, cb, opaque);
 546}
 547
 548/**
 549 * timer_new_ns:
 550 * @clock: the clock to associate with the timer
 551 * @callback: the callback to call when the timer expires
 552 * @opaque: the opaque pointer to pass to the callback
 553 *
 554 * Create a new timer with nanosecond scale on the default timer list
 555 * associated with the clock.
 556 *
 557 * Returns: a pointer to the newly created timer
 558 */
 559static inline QEMUTimer *timer_new_ns(QEMUClockType type, QEMUTimerCB *cb,
 560                                      void *opaque)
 561{
 562    return timer_new(type, SCALE_NS, cb, opaque);
 563}
 564
 565/**
 566 * timer_new_us:
 567 * @clock: the clock to associate with the timer
 568 * @callback: the callback to call when the timer expires
 569 * @opaque: the opaque pointer to pass to the callback
 570 *
 571 * Create a new timer with microsecond scale on the default timer list
 572 * associated with the clock.
 573 *
 574 * Returns: a pointer to the newly created timer
 575 */
 576static inline QEMUTimer *timer_new_us(QEMUClockType type, QEMUTimerCB *cb,
 577                                      void *opaque)
 578{
 579    return timer_new(type, SCALE_US, cb, opaque);
 580}
 581
 582/**
 583 * timer_new_ms:
 584 * @clock: the clock to associate with the timer
 585 * @callback: the callback to call when the timer expires
 586 * @opaque: the opaque pointer to pass to the callback
 587 *
 588 * Create a new timer with millisecond scale on the default timer list
 589 * associated with the clock.
 590 *
 591 * Returns: a pointer to the newly created timer
 592 */
 593static inline QEMUTimer *timer_new_ms(QEMUClockType type, QEMUTimerCB *cb,
 594                                      void *opaque)
 595{
 596    return timer_new(type, SCALE_MS, cb, opaque);
 597}
 598
 599/**
 600 * timer_deinit:
 601 * @ts: the timer to be de-initialised
 602 *
 603 * Deassociate the timer from any timerlist.  You should
 604 * call timer_del before.  After this call, any further
 605 * timer_del call cannot cause dangling pointer accesses
 606 * even if the previously used timerlist is freed.
 607 */
 608void timer_deinit(QEMUTimer *ts);
 609
 610/**
 611 * timer_free:
 612 * @ts: the timer
 613 *
 614 * Free a timer (it must not be on the active list)
 615 */
 616void timer_free(QEMUTimer *ts);
 617
 618/**
 619 * timer_del:
 620 * @ts: the timer
 621 *
 622 * Delete a timer from the active list.
 623 *
 624 * This function is thread-safe but the timer and its timer list must not be
 625 * freed while this function is running.
 626 */
 627void timer_del(QEMUTimer *ts);
 628
 629/**
 630 * timer_mod_ns:
 631 * @ts: the timer
 632 * @expire_time: the expiry time in nanoseconds
 633 *
 634 * Modify a timer to expire at @expire_time
 635 *
 636 * This function is thread-safe but the timer and its timer list must not be
 637 * freed while this function is running.
 638 */
 639void timer_mod_ns(QEMUTimer *ts, int64_t expire_time);
 640
 641/**
 642 * timer_mod_anticipate_ns:
 643 * @ts: the timer
 644 * @expire_time: the expiry time in nanoseconds
 645 *
 646 * Modify a timer to expire at @expire_time or the current time,
 647 * whichever comes earlier.
 648 *
 649 * This function is thread-safe but the timer and its timer list must not be
 650 * freed while this function is running.
 651 */
 652void timer_mod_anticipate_ns(QEMUTimer *ts, int64_t expire_time);
 653
 654/**
 655 * timer_mod:
 656 * @ts: the timer
 657 * @expire_time: the expire time in the units associated with the timer
 658 *
 659 * Modify a timer to expiry at @expire_time, taking into
 660 * account the scale associated with the timer.
 661 *
 662 * This function is thread-safe but the timer and its timer list must not be
 663 * freed while this function is running.
 664 */
 665void timer_mod(QEMUTimer *ts, int64_t expire_timer);
 666
 667/**
 668 * timer_mod_anticipate:
 669 * @ts: the timer
 670 * @expire_time: the expiry time in nanoseconds
 671 *
 672 * Modify a timer to expire at @expire_time or the current time, whichever
 673 * comes earlier, taking into account the scale associated with the timer.
 674 *
 675 * This function is thread-safe but the timer and its timer list must not be
 676 * freed while this function is running.
 677 */
 678void timer_mod_anticipate(QEMUTimer *ts, int64_t expire_time);
 679
 680/**
 681 * timer_pending:
 682 * @ts: the timer
 683 *
 684 * Determines whether a timer is pending (i.e. is on the
 685 * active list of timers, whether or not it has not yet expired).
 686 *
 687 * Returns: true if the timer is pending
 688 */
 689bool timer_pending(QEMUTimer *ts);
 690
 691/**
 692 * timer_expired:
 693 * @ts: the timer
 694 *
 695 * Determines whether a timer has expired.
 696 *
 697 * Returns: true if the timer has expired
 698 */
 699bool timer_expired(QEMUTimer *timer_head, int64_t current_time);
 700
 701/**
 702 * timer_expire_time_ns:
 703 * @ts: the timer
 704 *
 705 * Determine the expiry time of a timer
 706 *
 707 * Returns: the expiry time in nanoseconds
 708 */
 709uint64_t timer_expire_time_ns(QEMUTimer *ts);
 710
 711/**
 712 * timer_get:
 713 * @f: the file
 714 * @ts: the timer
 715 *
 716 * Read a timer @ts from a file @f
 717 */
 718void timer_get(QEMUFile *f, QEMUTimer *ts);
 719
 720/**
 721 * timer_put:
 722 * @f: the file
 723 * @ts: the timer
 724 */
 725void timer_put(QEMUFile *f, QEMUTimer *ts);
 726
 727/*
 728 * General utility functions
 729 */
 730
 731/**
 732 * qemu_timeout_ns_to_ms:
 733 * @ns: nanosecond timeout value
 734 *
 735 * Convert a nanosecond timeout value (or -1) to
 736 * a millisecond value (or -1), always rounding up.
 737 *
 738 * Returns: millisecond timeout value
 739 */
 740int qemu_timeout_ns_to_ms(int64_t ns);
 741
 742/**
 743 * qemu_poll_ns:
 744 * @fds: Array of file descriptors
 745 * @nfds: number of file descriptors
 746 * @timeout: timeout in nanoseconds
 747 *
 748 * Perform a poll like g_poll but with a timeout in nanoseconds.
 749 * See g_poll documentation for further details.
 750 *
 751 * Returns: number of fds ready
 752 */
 753int qemu_poll_ns(GPollFD *fds, guint nfds, int64_t timeout);
 754
 755/**
 756 * qemu_soonest_timeout:
 757 * @timeout1: first timeout in nanoseconds (or -1 for infinite)
 758 * @timeout2: second timeout in nanoseconds (or -1 for infinite)
 759 *
 760 * Calculates the soonest of two timeout values. -1 means infinite, which
 761 * is later than any other value.
 762 *
 763 * Returns: soonest timeout value in nanoseconds (or -1 for infinite)
 764 */
 765static inline int64_t qemu_soonest_timeout(int64_t timeout1, int64_t timeout2)
 766{
 767    /* we can abuse the fact that -1 (which means infinite) is a maximal
 768     * value when cast to unsigned. As this is disgusting, it's kept in
 769     * one inline function.
 770     */
 771    return ((uint64_t) timeout1 < (uint64_t) timeout2) ? timeout1 : timeout2;
 772}
 773
 774/**
 775 * initclocks:
 776 *
 777 * Initialise the clock & timer infrastructure
 778 */
 779void init_clocks(void);
 780
 781int64_t cpu_get_ticks(void);
 782/* Caller must hold BQL */
 783void cpu_enable_ticks(void);
 784/* Caller must hold BQL */
 785void cpu_disable_ticks(void);
 786
 787static inline int64_t get_max_clock_jump(void)
 788{
 789    /* This should be small enough to prevent excessive interrupts from being
 790     * generated by the RTC on clock jumps, but large enough to avoid frequent
 791     * unnecessary resets in idle VMs.
 792     */
 793    return 60 * NANOSECONDS_PER_SECOND;
 794}
 795
 796/*
 797 * Low level clock functions
 798 */
 799
 800/* real time host monotonic timer */
 801static inline int64_t get_clock_realtime(void)
 802{
 803    struct timeval tv;
 804
 805    gettimeofday(&tv, NULL);
 806    return tv.tv_sec * 1000000000LL + (tv.tv_usec * 1000);
 807}
 808
 809/* Warning: don't insert tracepoints into these functions, they are
 810   also used by simpletrace backend and tracepoints would cause
 811   an infinite recursion! */
 812#ifdef _WIN32
 813extern int64_t clock_freq;
 814
 815static inline int64_t get_clock(void)
 816{
 817    LARGE_INTEGER ti;
 818    QueryPerformanceCounter(&ti);
 819    return muldiv64(ti.QuadPart, NANOSECONDS_PER_SECOND, clock_freq);
 820}
 821
 822#else
 823
 824extern int use_rt_clock;
 825
 826static inline int64_t get_clock(void)
 827{
 828#ifdef CLOCK_MONOTONIC
 829    if (use_rt_clock) {
 830        struct timespec ts;
 831        clock_gettime(CLOCK_MONOTONIC, &ts);
 832        return ts.tv_sec * 1000000000LL + ts.tv_nsec;
 833    } else
 834#endif
 835    {
 836        /* XXX: using gettimeofday leads to problems if the date
 837           changes, so it should be avoided. */
 838        return get_clock_realtime();
 839    }
 840}
 841#endif
 842
 843/* icount */
 844int64_t cpu_get_icount_raw(void);
 845int64_t cpu_get_icount(void);
 846int64_t cpu_get_clock(void);
 847int64_t cpu_icount_to_ns(int64_t icount);
 848
 849/*******************************************/
 850/* host CPU ticks (if available) */
 851
 852#if defined(_ARCH_PPC)
 853
 854static inline int64_t cpu_get_host_ticks(void)
 855{
 856    int64_t retval;
 857#ifdef _ARCH_PPC64
 858    /* This reads timebase in one 64bit go and includes Cell workaround from:
 859       http://ozlabs.org/pipermail/linuxppc-dev/2006-October/027052.html
 860    */
 861    __asm__ __volatile__ ("mftb    %0\n\t"
 862                          "cmpwi   %0,0\n\t"
 863                          "beq-    $-8"
 864                          : "=r" (retval));
 865#else
 866    /* http://ozlabs.org/pipermail/linuxppc-dev/1999-October/003889.html */
 867    unsigned long junk;
 868    __asm__ __volatile__ ("mfspr   %1,269\n\t"  /* mftbu */
 869                          "mfspr   %L0,268\n\t" /* mftb */
 870                          "mfspr   %0,269\n\t"  /* mftbu */
 871                          "cmpw    %0,%1\n\t"
 872                          "bne     $-16"
 873                          : "=r" (retval), "=r" (junk));
 874#endif
 875    return retval;
 876}
 877
 878#elif defined(__i386__)
 879
 880static inline int64_t cpu_get_host_ticks(void)
 881{
 882    int64_t val;
 883    asm volatile ("rdtsc" : "=A" (val));
 884    return val;
 885}
 886
 887#elif defined(__x86_64__)
 888
 889static inline int64_t cpu_get_host_ticks(void)
 890{
 891    uint32_t low,high;
 892    int64_t val;
 893    asm volatile("rdtsc" : "=a" (low), "=d" (high));
 894    val = high;
 895    val <<= 32;
 896    val |= low;
 897    return val;
 898}
 899
 900#elif defined(__hppa__)
 901
 902static inline int64_t cpu_get_host_ticks(void)
 903{
 904    int val;
 905    asm volatile ("mfctl %%cr16, %0" : "=r"(val));
 906    return val;
 907}
 908
 909#elif defined(__ia64)
 910
 911static inline int64_t cpu_get_host_ticks(void)
 912{
 913    int64_t val;
 914    asm volatile ("mov %0 = ar.itc" : "=r"(val) :: "memory");
 915    return val;
 916}
 917
 918#elif defined(__s390__)
 919
 920static inline int64_t cpu_get_host_ticks(void)
 921{
 922    int64_t val;
 923    asm volatile("stck 0(%1)" : "=m" (val) : "a" (&val) : "cc");
 924    return val;
 925}
 926
 927#elif defined(__sparc__)
 928
 929static inline int64_t cpu_get_host_ticks (void)
 930{
 931#if defined(_LP64)
 932    uint64_t        rval;
 933    asm volatile("rd %%tick,%0" : "=r"(rval));
 934    return rval;
 935#else
 936    /* We need an %o or %g register for this.  For recent enough gcc
 937       there is an "h" constraint for that.  Don't bother with that.  */
 938    union {
 939        uint64_t i64;
 940        struct {
 941            uint32_t high;
 942            uint32_t low;
 943        }       i32;
 944    } rval;
 945    asm volatile("rd %%tick,%%g1; srlx %%g1,32,%0; mov %%g1,%1"
 946                 : "=r"(rval.i32.high), "=r"(rval.i32.low) : : "g1");
 947    return rval.i64;
 948#endif
 949}
 950
 951#elif defined(__mips__) && \
 952    ((defined(__mips_isa_rev) && __mips_isa_rev >= 2) || defined(__linux__))
 953/*
 954 * binutils wants to use rdhwr only on mips32r2
 955 * but as linux kernel emulate it, it's fine
 956 * to use it.
 957 *
 958 */
 959#define MIPS_RDHWR(rd, value) {                         \
 960        __asm__ __volatile__ (".set   push\n\t"         \
 961                              ".set mips32r2\n\t"       \
 962                              "rdhwr  %0, "rd"\n\t"     \
 963                              ".set   pop"              \
 964                              : "=r" (value));          \
 965    }
 966
 967static inline int64_t cpu_get_host_ticks(void)
 968{
 969    /* On kernels >= 2.6.25 rdhwr <reg>, $2 and $3 are emulated */
 970    uint32_t count;
 971    static uint32_t cyc_per_count = 0;
 972
 973    if (!cyc_per_count) {
 974        MIPS_RDHWR("$3", cyc_per_count);
 975    }
 976
 977    MIPS_RDHWR("$2", count);
 978    return (int64_t)(count * cyc_per_count);
 979}
 980
 981#elif defined(__alpha__)
 982
 983static inline int64_t cpu_get_host_ticks(void)
 984{
 985    uint64_t cc;
 986    uint32_t cur, ofs;
 987
 988    asm volatile("rpcc %0" : "=r"(cc));
 989    cur = cc;
 990    ofs = cc >> 32;
 991    return cur - ofs;
 992}
 993
 994#else
 995/* The host CPU doesn't have an easily accessible cycle counter.
 996   Just return a monotonically increasing value.  This will be
 997   totally wrong, but hopefully better than nothing.  */
 998static inline int64_t cpu_get_host_ticks (void)
 999{
1000    static int64_t ticks = 0;
1001    return ticks++;
1002}
1003#endif
1004
1005#ifdef CONFIG_PROFILER
1006static inline int64_t profile_getclock(void)
1007{
1008    return get_clock();
1009}
1010
1011extern int64_t tcg_time;
1012extern int64_t dev_time;
1013#endif
1014
1015#endif
1016