include/qemu/timer.h

   1 #ifndef QEMU_TIMER_H
   2 #define QEMU_TIMER_H
   3
   4 #include "qemu/typedefs.h"
   5 #include "qemu-common.h"
   6 #include "qemu/notify.h"
   7
   8 #define NANOSECONDS_PER_SECOND 1000000000LL
   9
  10 /* timers */
  11
  12 #define SCALE_MS 1000000
  13 #define SCALE_US 1000
  14 #define SCALE_NS 1
  15
  16 /**
  17  * QEMUClockType:
  18  *
  19  * The following clock types are available:
  20  *
  21  * @QEMU_CLOCK_REALTIME: Real time clock
  22  *
  23  * The real time clock should be used only for stuff which does not
  24  * change the virtual machine state, as it is run even if the virtual
  25  * machine is stopped. The real time clock has a frequency of 1000
  26  * Hz.
  27  *
  28  * @QEMU_CLOCK_VIRTUAL: virtual clock
  29  *
  30  * The virtual clock is only run during the emulation. It is stopped
  31  * when the virtual machine is stopped. Virtual timers use a high
  32  * precision clock, usually cpu cycles (use ticks_per_sec).
  33  *
  34  * @QEMU_CLOCK_HOST: host clock
  35  *
  36  * The host clock should be use for device models that emulate accurate
  37  * real time sources. It will continue to run when the virtual machine
  38  * is suspended, and it will reflect system time changes the host may
  39  * undergo (e.g. due to NTP). The host clock has the same precision as
  40  * the virtual clock.
  41  *
  42  * @QEMU_CLOCK_VIRTUAL_RT: realtime clock used for icount warp
  43  *
  44  * Outside icount mode, this clock is the same as @QEMU_CLOCK_VIRTUAL.
  45  * In icount mode, this clock counts nanoseconds while the virtual
  46  * machine is running.  It is used to increase @QEMU_CLOCK_VIRTUAL
  47  * while the CPUs are sleeping and thus not executing instructions.
  48  */
  49
  50 typedef enum {
  51     QEMU_CLOCK_REALTIME = 0,
  52     QEMU_CLOCK_VIRTUAL = 1,
  53     QEMU_CLOCK_HOST = 2,
  54     QEMU_CLOCK_VIRTUAL_RT = 3,
  55     QEMU_CLOCK_MAX
  56 } QEMUClockType;
  57
  58 typedef struct QEMUTimerList QEMUTimerList;
  59
  60 struct QEMUTimerListGroup {
  61     QEMUTimerList *tl[QEMU_CLOCK_MAX];
  62 };
  63
  64 typedef void QEMUTimerCB(void *opaque);
  65 typedef void QEMUTimerListNotifyCB(void *opaque);
  66
  67 struct QEMUTimer {
  68     int64_t expire_time;        /* in nanoseconds */
  69     QEMUTimerList *timer_list;
  70     QEMUTimerCB *cb;
  71     void *opaque;
  72     QEMUTimer *next;
  73     int scale;
  74 };
  75
  76 extern QEMUTimerListGroup main_loop_tlg;
  77
  78 /*
  79  * QEMUClockType
  80  */
  81
  82 /*
  83  * qemu_clock_get_ns;
  84  * @type: the clock type
  85  *
  86  * Get the nanosecond value of a clock with
  87  * type @type
  88  *
  89  * Returns: the clock value in nanoseconds
  90  */
  91 int64_t qemu_clock_get_ns(QEMUClockType type);
  92
  93 /**
  94  * qemu_clock_get_ms;
  95  * @type: the clock type
  96  *
  97  * Get the millisecond value of a clock with
  98  * type @type
  99  *
 100  * Returns: the clock value in milliseconds
 101  */
 102 static inline int64_t qemu_clock_get_ms(QEMUClockType type)
 103 {
 104     return qemu_clock_get_ns(type) / SCALE_MS;
 105 }
 106
 107 /**
 108  * qemu_clock_get_us;
 109  * @type: the clock type
 110  *
 111  * Get the microsecond value of a clock with
 112  * type @type
 113  *
 114  * Returns: the clock value in microseconds
 115  */
 116 static inline int64_t qemu_clock_get_us(QEMUClockType type)
 117 {
 118     return qemu_clock_get_ns(type) / SCALE_US;
 119 }
 120
 121 /**
 122  * qemu_clock_has_timers:
 123  * @type: the clock type
 124  *
 125  * Determines whether a clock's default timer list
 126  * has timers attached
 127  *
 128  * Note that this function should not be used when other threads also access
 129  * the timer list.  The return value may be outdated by the time it is acted
 130  * upon.
 131  *
 132  * Returns: true if the clock's default timer list
 133  * has timers attached
 134  */
 135 bool qemu_clock_has_timers(QEMUClockType type);
 136
 137 /**
 138  * qemu_clock_expired:
 139  * @type: the clock type
 140  *
 141  * Determines whether a clock's default timer list
 142  * has an expired clock.
 143  *
 144  * Returns: true if the clock's default timer list has
 145  * an expired timer
 146  */
 147 bool qemu_clock_expired(QEMUClockType type);
 148
 149 /**
 150  * qemu_clock_use_for_deadline:
 151  * @type: the clock type
 152  *
 153  * Determine whether a clock should be used for deadline
 154  * calculations. Some clocks, for instance vm_clock with
 155  * use_icount set, do not count in nanoseconds. Such clocks
 156  * are not used for deadline calculations, and are presumed
 157  * to interrupt any poll using qemu_notify/aio_notify
 158  * etc.
 159  *
 160  * Returns: true if the clock runs in nanoseconds and
 161  * should be used for a deadline.
 162  */
 163 bool qemu_clock_use_for_deadline(QEMUClockType type);
 164
 165 /**
 166  * qemu_clock_deadline_ns_all:
 167  * @type: the clock type
 168  *
 169  * Calculate the deadline across all timer lists associated
 170  * with a clock (as opposed to just the default one)
 171  * in nanoseconds, or -1 if no timer is set to expire.
 172  *
 173  * Returns: time until expiry in nanoseconds or -1
 174  */
 175 int64_t qemu_clock_deadline_ns_all(QEMUClockType type);
 176
 177 /**
 178  * qemu_clock_get_main_loop_timerlist:
 179  * @type: the clock type
 180  *
 181  * Return the default timer list assocatiated with a clock.
 182  *
 183  * Returns: the default timer list
 184  */
 185 QEMUTimerList *qemu_clock_get_main_loop_timerlist(QEMUClockType type);
 186
 187 /**
 188  * qemu_clock_nofify:
 189  * @type: the clock type
 190  *
 191  * Call the notifier callback connected with the default timer
 192  * list linked to the clock, or qemu_notify() if none.
 193  */
 194 void qemu_clock_notify(QEMUClockType type);
 195
 196 /**
 197  * qemu_clock_enable:
 198  * @type: the clock type
 199  * @enabled: true to enable, false to disable
 200  *
 201  * Enable or disable a clock
 202  * Disabling the clock will wait for related timerlists to stop
 203  * executing qemu_run_timers.  Thus, this functions should not
 204  * be used from the callback of a timer that is based on @clock.
 205  * Doing so would cause a deadlock.
 206  *
 207  * Caller should hold BQL.
 208  */
 209 void qemu_clock_enable(QEMUClockType type, bool enabled);
 210
 211 /**
 212  * qemu_clock_warp:
 213  * @type: the clock type
 214  *
 215  * Warp a clock to a new value
 216  */
 217 void qemu_clock_warp(QEMUClockType type);
 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  */
 227 void 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  */
 238 void 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  */
 250 bool 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  */
 260 bool 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  */
 277 QEMUTimerList *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  */
 286 void 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  */
 300 bool 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  */
 312 bool 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  */
 325 int64_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  */
 336 QEMUClockType 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  */
 346 bool 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  */
 354 void 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  */
 373 void 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  */
 383 void 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  */
 394 bool 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  */
 408 int64_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  */
 428 void 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  */
 445 static 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  */
 463 static 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  */
 481 static 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  */
 499 static 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  */
 520 static 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  */
 542 static 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  */
 559 static 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  */
 576 static 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  */
 593 static 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  */
 608 void 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  */
 616 void 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  */
 627 void 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  */
 639 void 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  */
 652 void 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  */
 665 void 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  */
 678 void 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  */
 689 bool 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  */
 699 bool 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  */
 709 uint64_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  */
 718 void timer_get(QEMUFile *f, QEMUTimer *ts);
 719
 720 /**
 721  * timer_put:
 722  * @f: the file
 723  * @ts: the timer
 724  */
 725 void 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  */
 740 int 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  */
 753 int 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  */
 765 static 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  */
 779 void init_clocks(void);
 780
 781 int64_t cpu_get_ticks(void);
 782 /* Caller must hold BQL */
 783 void cpu_enable_ticks(void);
 784 /* Caller must hold BQL */
 785 void cpu_disable_ticks(void);
 786
 787 static inline int64_t get_ticks_per_sec(void)
 788 {
 789     return 1000000000LL;
 790 }
 791
 792 static inline int64_t get_max_clock_jump(void)
 793 {
 794     /* This should be small enough to prevent excessive interrupts from being
 795      * generated by the RTC on clock jumps, but large enough to avoid frequent
 796      * unnecessary resets in idle VMs.
 797      */
 798     return 60 * get_ticks_per_sec();
 799 }
 800
 801 /*
 802  * Low level clock functions
 803  */
 804
 805 /* real time host monotonic timer */
 806 static inline int64_t get_clock_realtime(void)
 807 {
 808     struct timeval tv;
 809
 810     gettimeofday(&tv, NULL);
 811     return tv.tv_sec * 1000000000LL + (tv.tv_usec * 1000);
 812 }
 813
 814 /* Warning: don't insert tracepoints into these functions, they are
 815    also used by simpletrace backend and tracepoints would cause
 816    an infinite recursion! */
 817 #ifdef _WIN32
 818 extern int64_t clock_freq;
 819
 820 static inline int64_t get_clock(void)
 821 {
 822     LARGE_INTEGER ti;
 823     QueryPerformanceCounter(&ti);
 824     return muldiv64(ti.QuadPart, get_ticks_per_sec(), clock_freq);
 825 }
 826
 827 #else
 828
 829 extern int use_rt_clock;
 830
 831 static inline int64_t get_clock(void)
 832 {
 833 #ifdef CLOCK_MONOTONIC
 834     if (use_rt_clock) {
 835         struct timespec ts;
 836         clock_gettime(CLOCK_MONOTONIC, &ts);
 837         return ts.tv_sec * 1000000000LL + ts.tv_nsec;
 838     } else
 839 #endif
 840     {
 841         /* XXX: using gettimeofday leads to problems if the date
 842            changes, so it should be avoided. */
 843         return get_clock_realtime();
 844     }
 845 }
 846 #endif
 847
 848 /* icount */
 849 int64_t cpu_get_icount_raw(void);
 850 int64_t cpu_get_icount(void);
 851 int64_t cpu_get_clock(void);
 852 int64_t cpu_icount_to_ns(int64_t icount);
 853
 854 /*******************************************/
 855 /* host CPU ticks (if available) */
 856
 857 #if defined(_ARCH_PPC)
 858
 859 static inline int64_t cpu_get_real_ticks(void)
 860 {
 861     int64_t retval;
 862 #ifdef _ARCH_PPC64
 863     /* This reads timebase in one 64bit go and includes Cell workaround from:
 864        http://ozlabs.org/pipermail/linuxppc-dev/2006-October/027052.html
 865     */
 866     __asm__ __volatile__ ("mftb    %0\n\t"
 867                           "cmpwi   %0,0\n\t"
 868                           "beq-    $-8"
 869                           : "=r" (retval));
 870 #else
 871     /* http://ozlabs.org/pipermail/linuxppc-dev/1999-October/003889.html */
 872     unsigned long junk;
 873     __asm__ __volatile__ ("mfspr   %1,269\n\t"  /* mftbu */
 874                           "mfspr   %L0,268\n\t" /* mftb */
 875                           "mfspr   %0,269\n\t"  /* mftbu */
 876                           "cmpw    %0,%1\n\t"
 877                           "bne     $-16"
 878                           : "=r" (retval), "=r" (junk));
 879 #endif
 880     return retval;
 881 }
 882
 883 #elif defined(__i386__)
 884
 885 static inline int64_t cpu_get_real_ticks(void)
 886 {
 887     int64_t val;
 888     asm volatile ("rdtsc" : "=A" (val));
 889     return val;
 890 }
 891
 892 #elif defined(__x86_64__)
 893
 894 static inline int64_t cpu_get_real_ticks(void)
 895 {
 896     uint32_t low,high;
 897     int64_t val;
 898     asm volatile("rdtsc" : "=a" (low), "=d" (high));
 899     val = high;
 900     val <<= 32;
 901     val |= low;
 902     return val;
 903 }
 904
 905 #elif defined(__hppa__)
 906
 907 static inline int64_t cpu_get_real_ticks(void)
 908 {
 909     int val;
 910     asm volatile ("mfctl %%cr16, %0" : "=r"(val));
 911     return val;
 912 }
 913
 914 #elif defined(__ia64)
 915
 916 static inline int64_t cpu_get_real_ticks(void)
 917 {
 918     int64_t val;
 919     asm volatile ("mov %0 = ar.itc" : "=r"(val) :: "memory");
 920     return val;
 921 }
 922
 923 #elif defined(__s390__)
 924
 925 static inline int64_t cpu_get_real_ticks(void)
 926 {
 927     int64_t val;
 928     asm volatile("stck 0(%1)" : "=m" (val) : "a" (&val) : "cc");
 929     return val;
 930 }
 931
 932 #elif defined(__sparc__)
 933
 934 static inline int64_t cpu_get_real_ticks (void)
 935 {
 936 #if defined(_LP64)
 937     uint64_t        rval;
 938     asm volatile("rd %%tick,%0" : "=r"(rval));
 939     return rval;
 940 #else
 941     /* We need an %o or %g register for this.  For recent enough gcc
 942        there is an "h" constraint for that.  Don't bother with that.  */
 943     union {
 944         uint64_t i64;
 945         struct {
 946             uint32_t high;
 947             uint32_t low;
 948         }       i32;
 949     } rval;
 950     asm volatile("rd %%tick,%%g1; srlx %%g1,32,%0; mov %%g1,%1"
 951                  : "=r"(rval.i32.high), "=r"(rval.i32.low) : : "g1");
 952     return rval.i64;
 953 #endif
 954 }
 955
 956 #elif defined(__mips__) && \
 957     ((defined(__mips_isa_rev) && __mips_isa_rev >= 2) || defined(__linux__))
 958 /*
 959  * binutils wants to use rdhwr only on mips32r2
 960  * but as linux kernel emulate it, it's fine
 961  * to use it.
 962  *
 963  */
 964 #define MIPS_RDHWR(rd, value) {                         \
 965         __asm__ __volatile__ (".set   push\n\t"         \
 966                               ".set mips32r2\n\t"       \
 967                               "rdhwr  %0, "rd"\n\t"     \
 968                               ".set   pop"              \
 969                               : "=r" (value));          \
 970     }
 971
 972 static inline int64_t cpu_get_real_ticks(void)
 973 {
 974     /* On kernels >= 2.6.25 rdhwr <reg>, $2 and $3 are emulated */
 975     uint32_t count;
 976     static uint32_t cyc_per_count = 0;
 977
 978     if (!cyc_per_count) {
 979         MIPS_RDHWR("$3", cyc_per_count);
 980     }
 981
 982     MIPS_RDHWR("$2", count);
 983     return (int64_t)(count * cyc_per_count);
 984 }
 985
 986 #elif defined(__alpha__)
 987
 988 static inline int64_t cpu_get_real_ticks(void)
 989 {
 990     uint64_t cc;
 991     uint32_t cur, ofs;
 992
 993     asm volatile("rpcc %0" : "=r"(cc));
 994     cur = cc;
 995     ofs = cc >> 32;
 996     return cur - ofs;
 997 }
 998
 999 #else
1000 /* The host CPU doesn't have an easily accessible cycle counter.
1001    Just return a monotonically increasing value.  This will be
1002    totally wrong, but hopefully better than nothing.  */
1003 static inline int64_t cpu_get_real_ticks (void)
1004 {
1005     static int64_t ticks = 0;
1006     return ticks++;
1007 }
1008 #endif
1009
1010 #ifdef CONFIG_PROFILER
1011 static inline int64_t profile_getclock(void)
1012 {
1013     return get_clock();
1014 }
1015
1016 extern int64_t tcg_time;
1017 extern int64_t dev_time;
1018 #endif
1019
1020 #endif