/* * QEMU System Emulator * * Copyright (c) 2003-2008 Fabrice Bellard * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "sysemu.h" #include "monitor/monitor.h" #include "ui/console.h" #include "hw/hw.h" #include "qemu-timer.h" #ifdef CONFIG_POSIX #include #endif #ifdef _WIN32 #include #endif /***********************************************************/ /* timers */ #define QEMU_CLOCK_REALTIME 0 #define QEMU_CLOCK_VIRTUAL 1 #define QEMU_CLOCK_HOST 2 struct QEMUClock { QEMUTimer *active_timers; NotifierList reset_notifiers; int64_t last; int type; bool enabled; }; struct QEMUTimer { int64_t expire_time; /* in nanoseconds */ QEMUClock *clock; QEMUTimerCB *cb; void *opaque; QEMUTimer *next; int scale; }; struct qemu_alarm_timer { char const *name; int (*start)(struct qemu_alarm_timer *t); void (*stop)(struct qemu_alarm_timer *t); void (*rearm)(struct qemu_alarm_timer *t, int64_t nearest_delta_ns); #if defined(__linux__) timer_t timer; int fd; #elif defined(_WIN32) HANDLE timer; #endif bool expired; bool pending; }; static struct qemu_alarm_timer *alarm_timer; static bool qemu_timer_expired_ns(QEMUTimer *timer_head, int64_t current_time) { return timer_head && (timer_head->expire_time <= current_time); } static int64_t qemu_next_alarm_deadline(void) { int64_t delta = INT64_MAX; int64_t rtdelta; if (!use_icount && vm_clock->enabled && vm_clock->active_timers) { delta = vm_clock->active_timers->expire_time - qemu_get_clock_ns(vm_clock); } if (host_clock->enabled && host_clock->active_timers) { int64_t hdelta = host_clock->active_timers->expire_time - qemu_get_clock_ns(host_clock); if (hdelta < delta) { delta = hdelta; } } if (rt_clock->enabled && rt_clock->active_timers) { rtdelta = (rt_clock->active_timers->expire_time - qemu_get_clock_ns(rt_clock)); if (rtdelta < delta) { delta = rtdelta; } } return delta; } static void qemu_rearm_alarm_timer(struct qemu_alarm_timer *t) { int64_t nearest_delta_ns = qemu_next_alarm_deadline(); if (nearest_delta_ns < INT64_MAX) { t->rearm(t, nearest_delta_ns); } } /* TODO: MIN_TIMER_REARM_NS should be optimized */ #define MIN_TIMER_REARM_NS 250000 #ifdef _WIN32 static int mm_start_timer(struct qemu_alarm_timer *t); static void mm_stop_timer(struct qemu_alarm_timer *t); static void mm_rearm_timer(struct qemu_alarm_timer *t, int64_t delta); static int win32_start_timer(struct qemu_alarm_timer *t); static void win32_stop_timer(struct qemu_alarm_timer *t); static void win32_rearm_timer(struct qemu_alarm_timer *t, int64_t delta); #else static int unix_start_timer(struct qemu_alarm_timer *t); static void unix_stop_timer(struct qemu_alarm_timer *t); static void unix_rearm_timer(struct qemu_alarm_timer *t, int64_t delta); #ifdef __linux__ static int dynticks_start_timer(struct qemu_alarm_timer *t); static void dynticks_stop_timer(struct qemu_alarm_timer *t); static void dynticks_rearm_timer(struct qemu_alarm_timer *t, int64_t delta); #endif /* __linux__ */ #endif /* _WIN32 */ static struct qemu_alarm_timer alarm_timers[] = { #ifndef _WIN32 #ifdef __linux__ {"dynticks", dynticks_start_timer, dynticks_stop_timer, dynticks_rearm_timer}, #endif {"unix", unix_start_timer, unix_stop_timer, unix_rearm_timer}, #else {"mmtimer", mm_start_timer, mm_stop_timer, mm_rearm_timer}, {"dynticks", win32_start_timer, win32_stop_timer, win32_rearm_timer}, #endif {NULL, } }; static void show_available_alarms(void) { int i; printf("Available alarm timers, in order of precedence:\n"); for (i = 0; alarm_timers[i].name; i++) printf("%s\n", alarm_timers[i].name); } void configure_alarms(char const *opt) { int i; int cur = 0; int count = ARRAY_SIZE(alarm_timers) - 1; char *arg; char *name; struct qemu_alarm_timer tmp; if (is_help_option(opt)) { show_available_alarms(); exit(0); } arg = g_strdup(opt); /* Reorder the array */ name = strtok(arg, ","); while (name) { for (i = 0; i < count && alarm_timers[i].name; i++) { if (!strcmp(alarm_timers[i].name, name)) break; } if (i == count) { fprintf(stderr, "Unknown clock %s\n", name); goto next; } if (i < cur) /* Ignore */ goto next; /* Swap */ tmp = alarm_timers[i]; alarm_timers[i] = alarm_timers[cur]; alarm_timers[cur] = tmp; cur++; next: name = strtok(NULL, ","); } g_free(arg); if (cur) { /* Disable remaining timers */ for (i = cur; i < count; i++) alarm_timers[i].name = NULL; } else { show_available_alarms(); exit(1); } } QEMUClock *rt_clock; QEMUClock *vm_clock; QEMUClock *host_clock; static QEMUClock *qemu_new_clock(int type) { QEMUClock *clock; clock = g_malloc0(sizeof(QEMUClock)); clock->type = type; clock->enabled = true; clock->last = INT64_MIN; notifier_list_init(&clock->reset_notifiers); return clock; } void qemu_clock_enable(QEMUClock *clock, bool enabled) { bool old = clock->enabled; clock->enabled = enabled; if (enabled && !old) { qemu_rearm_alarm_timer(alarm_timer); } } int64_t qemu_clock_has_timers(QEMUClock *clock) { return !!clock->active_timers; } int64_t qemu_clock_expired(QEMUClock *clock) { return (clock->active_timers && clock->active_timers->expire_time < qemu_get_clock_ns(clock)); } int64_t qemu_clock_deadline(QEMUClock *clock) { /* To avoid problems with overflow limit this to 2^32. */ int64_t delta = INT32_MAX; if (clock->active_timers) { delta = clock->active_timers->expire_time - qemu_get_clock_ns(clock); } if (delta < 0) { delta = 0; } return delta; } QEMUTimer *qemu_new_timer(QEMUClock *clock, int scale, QEMUTimerCB *cb, void *opaque) { QEMUTimer *ts; ts = g_malloc0(sizeof(QEMUTimer)); ts->clock = clock; ts->cb = cb; ts->opaque = opaque; ts->scale = scale; return ts; } void qemu_free_timer(QEMUTimer *ts) { g_free(ts); } /* stop a timer, but do not dealloc it */ void qemu_del_timer(QEMUTimer *ts) { QEMUTimer **pt, *t; /* NOTE: this code must be signal safe because qemu_timer_expired() can be called from a signal. */ pt = &ts->clock->active_timers; for(;;) { t = *pt; if (!t) break; if (t == ts) { *pt = t->next; break; } pt = &t->next; } } /* modify the current timer so that it will be fired when current_time >= expire_time. The corresponding callback will be called. */ void qemu_mod_timer_ns(QEMUTimer *ts, int64_t expire_time) { QEMUTimer **pt, *t; qemu_del_timer(ts); /* add the timer in the sorted list */ /* NOTE: this code must be signal safe because qemu_timer_expired() can be called from a signal. */ pt = &ts->clock->active_timers; for(;;) { t = *pt; if (!qemu_timer_expired_ns(t, expire_time)) { break; } pt = &t->next; } ts->expire_time = expire_time; ts->next = *pt; *pt = ts; /* Rearm if necessary */ if (pt == &ts->clock->active_timers) { if (!alarm_timer->pending) { qemu_rearm_alarm_timer(alarm_timer); } /* Interrupt execution to force deadline recalculation. */ qemu_clock_warp(ts->clock); if (use_icount) { qemu_notify_event(); } } } void qemu_mod_timer(QEMUTimer *ts, int64_t expire_time) { qemu_mod_timer_ns(ts, expire_time * ts->scale); } bool qemu_timer_pending(QEMUTimer *ts) { QEMUTimer *t; for (t = ts->clock->active_timers; t != NULL; t = t->next) { if (t == ts) { return true; } } return false; } bool qemu_timer_expired(QEMUTimer *timer_head, int64_t current_time) { return qemu_timer_expired_ns(timer_head, current_time * timer_head->scale); } void qemu_run_timers(QEMUClock *clock) { QEMUTimer *ts; int64_t current_time; if (!clock->enabled) return; current_time = qemu_get_clock_ns(clock); for(;;) { ts = clock->active_timers; if (!qemu_timer_expired_ns(ts, current_time)) { break; } /* remove timer from the list before calling the callback */ clock->active_timers = ts->next; ts->next = NULL; /* run the callback (the timer list can be modified) */ ts->cb(ts->opaque); } } int64_t qemu_get_clock_ns(QEMUClock *clock) { int64_t now, last; switch(clock->type) { case QEMU_CLOCK_REALTIME: return get_clock(); default: case QEMU_CLOCK_VIRTUAL: if (use_icount) { return cpu_get_icount(); } else { return cpu_get_clock(); } case QEMU_CLOCK_HOST: now = get_clock_realtime(); last = clock->last; clock->last = now; if (now < last) { notifier_list_notify(&clock->reset_notifiers, &now); } return now; } } void qemu_register_clock_reset_notifier(QEMUClock *clock, Notifier *notifier) { notifier_list_add(&clock->reset_notifiers, notifier); } void qemu_unregister_clock_reset_notifier(QEMUClock *clock, Notifier *notifier) { notifier_remove(notifier); } void init_clocks(void) { if (!rt_clock) { rt_clock = qemu_new_clock(QEMU_CLOCK_REALTIME); vm_clock = qemu_new_clock(QEMU_CLOCK_VIRTUAL); host_clock = qemu_new_clock(QEMU_CLOCK_HOST); } } uint64_t qemu_timer_expire_time_ns(QEMUTimer *ts) { return qemu_timer_pending(ts) ? ts->expire_time : -1; } void qemu_run_all_timers(void) { alarm_timer->pending = false; /* vm time timers */ qemu_run_timers(vm_clock); qemu_run_timers(rt_clock); qemu_run_timers(host_clock); /* rearm timer, if not periodic */ if (alarm_timer->expired) { alarm_timer->expired = false; qemu_rearm_alarm_timer(alarm_timer); } } #ifdef _WIN32 static void CALLBACK host_alarm_handler(PVOID lpParam, BOOLEAN unused) #else static void host_alarm_handler(int host_signum) #endif { struct qemu_alarm_timer *t = alarm_timer; if (!t) return; t->expired = true; t->pending = true; qemu_notify_event(); } #if defined(__linux__) #include "compatfd.h" static int dynticks_start_timer(struct qemu_alarm_timer *t) { struct sigevent ev; timer_t host_timer; struct sigaction act; sigfillset(&act.sa_mask); act.sa_flags = 0; act.sa_handler = host_alarm_handler; sigaction(SIGALRM, &act, NULL); /* * Initialize ev struct to 0 to avoid valgrind complaining * about uninitialized data in timer_create call */ memset(&ev, 0, sizeof(ev)); ev.sigev_value.sival_int = 0; ev.sigev_notify = SIGEV_SIGNAL; #ifdef CONFIG_SIGEV_THREAD_ID if (qemu_signalfd_available()) { ev.sigev_notify = SIGEV_THREAD_ID; ev._sigev_un._tid = qemu_get_thread_id(); } #endif /* CONFIG_SIGEV_THREAD_ID */ ev.sigev_signo = SIGALRM; if (timer_create(CLOCK_REALTIME, &ev, &host_timer)) { perror("timer_create"); return -1; } t->timer = host_timer; return 0; } static void dynticks_stop_timer(struct qemu_alarm_timer *t) { timer_t host_timer = t->timer; timer_delete(host_timer); } static void dynticks_rearm_timer(struct qemu_alarm_timer *t, int64_t nearest_delta_ns) { timer_t host_timer = t->timer; struct itimerspec timeout; int64_t current_ns; if (nearest_delta_ns < MIN_TIMER_REARM_NS) nearest_delta_ns = MIN_TIMER_REARM_NS; /* check whether a timer is already running */ if (timer_gettime(host_timer, &timeout)) { perror("gettime"); fprintf(stderr, "Internal timer error: aborting\n"); exit(1); } current_ns = timeout.it_value.tv_sec * 1000000000LL + timeout.it_value.tv_nsec; if (current_ns && current_ns <= nearest_delta_ns) return; timeout.it_interval.tv_sec = 0; timeout.it_interval.tv_nsec = 0; /* 0 for one-shot timer */ timeout.it_value.tv_sec = nearest_delta_ns / 1000000000; timeout.it_value.tv_nsec = nearest_delta_ns % 1000000000; if (timer_settime(host_timer, 0 /* RELATIVE */, &timeout, NULL)) { perror("settime"); fprintf(stderr, "Internal timer error: aborting\n"); exit(1); } } #endif /* defined(__linux__) */ #if !defined(_WIN32) static int unix_start_timer(struct qemu_alarm_timer *t) { struct sigaction act; /* timer signal */ sigfillset(&act.sa_mask); act.sa_flags = 0; act.sa_handler = host_alarm_handler; sigaction(SIGALRM, &act, NULL); return 0; } static void unix_rearm_timer(struct qemu_alarm_timer *t, int64_t nearest_delta_ns) { struct itimerval itv; int err; if (nearest_delta_ns < MIN_TIMER_REARM_NS) nearest_delta_ns = MIN_TIMER_REARM_NS; itv.it_interval.tv_sec = 0; itv.it_interval.tv_usec = 0; /* 0 for one-shot timer */ itv.it_value.tv_sec = nearest_delta_ns / 1000000000; itv.it_value.tv_usec = (nearest_delta_ns % 1000000000) / 1000; err = setitimer(ITIMER_REAL, &itv, NULL); if (err) { perror("setitimer"); fprintf(stderr, "Internal timer error: aborting\n"); exit(1); } } static void unix_stop_timer(struct qemu_alarm_timer *t) { struct itimerval itv; memset(&itv, 0, sizeof(itv)); setitimer(ITIMER_REAL, &itv, NULL); } #endif /* !defined(_WIN32) */ #ifdef _WIN32 static MMRESULT mm_timer; static TIMECAPS mm_tc; static void CALLBACK mm_alarm_handler(UINT uTimerID, UINT uMsg, DWORD_PTR dwUser, DWORD_PTR dw1, DWORD_PTR dw2) { struct qemu_alarm_timer *t = alarm_timer; if (!t) { return; } t->expired = true; t->pending = true; qemu_notify_event(); } static int mm_start_timer(struct qemu_alarm_timer *t) { timeGetDevCaps(&mm_tc, sizeof(mm_tc)); timeBeginPeriod(mm_tc.wPeriodMin); mm_timer = timeSetEvent(mm_tc.wPeriodMin, /* interval (ms) */ mm_tc.wPeriodMin, /* resolution */ mm_alarm_handler, /* function */ (DWORD_PTR)t, /* parameter */ TIME_ONESHOT | TIME_CALLBACK_FUNCTION); if (!mm_timer) { fprintf(stderr, "Failed to initialize win32 alarm timer\n"); timeEndPeriod(mm_tc.wPeriodMin); return -1; } return 0; } static void mm_stop_timer(struct qemu_alarm_timer *t) { timeKillEvent(mm_timer); timeEndPeriod(mm_tc.wPeriodMin); } static void mm_rearm_timer(struct qemu_alarm_timer *t, int64_t delta) { int64_t nearest_delta_ms = delta / 1000000; if (nearest_delta_ms < mm_tc.wPeriodMin) { nearest_delta_ms = mm_tc.wPeriodMin; } else if (nearest_delta_ms > mm_tc.wPeriodMax) { nearest_delta_ms = mm_tc.wPeriodMax; } timeKillEvent(mm_timer); mm_timer = timeSetEvent((UINT)nearest_delta_ms, mm_tc.wPeriodMin, mm_alarm_handler, (DWORD_PTR)t, TIME_ONESHOT | TIME_CALLBACK_FUNCTION); if (!mm_timer) { fprintf(stderr, "Failed to re-arm win32 alarm timer\n"); timeEndPeriod(mm_tc.wPeriodMin); exit(1); } } static int win32_start_timer(struct qemu_alarm_timer *t) { HANDLE hTimer; BOOLEAN success; /* If you call ChangeTimerQueueTimer on a one-shot timer (its period is zero) that has already expired, the timer is not updated. Since creating a new timer is relatively expensive, set a bogus one-hour interval in the dynticks case. */ success = CreateTimerQueueTimer(&hTimer, NULL, host_alarm_handler, t, 1, 3600000, WT_EXECUTEINTIMERTHREAD); if (!success) { fprintf(stderr, "Failed to initialize win32 alarm timer: %ld\n", GetLastError()); return -1; } t->timer = hTimer; return 0; } static void win32_stop_timer(struct qemu_alarm_timer *t) { HANDLE hTimer = t->timer; if (hTimer) { DeleteTimerQueueTimer(NULL, hTimer, NULL); } } static void win32_rearm_timer(struct qemu_alarm_timer *t, int64_t nearest_delta_ns) { HANDLE hTimer = t->timer; int64_t nearest_delta_ms; BOOLEAN success; nearest_delta_ms = nearest_delta_ns / 1000000; if (nearest_delta_ms < 1) { nearest_delta_ms = 1; } /* ULONG_MAX can be 32 bit */ if (nearest_delta_ms > ULONG_MAX) { nearest_delta_ms = ULONG_MAX; } success = ChangeTimerQueueTimer(NULL, hTimer, (unsigned long) nearest_delta_ms, 3600000); if (!success) { fprintf(stderr, "Failed to rearm win32 alarm timer: %ld\n", GetLastError()); exit(-1); } } #endif /* _WIN32 */ static void quit_timers(void) { struct qemu_alarm_timer *t = alarm_timer; alarm_timer = NULL; t->stop(t); } #ifdef CONFIG_POSIX static void reinit_timers(void) { struct qemu_alarm_timer *t = alarm_timer; t->stop(t); if (t->start(t)) { fprintf(stderr, "Internal timer error: aborting\n"); exit(1); } qemu_rearm_alarm_timer(t); } #endif /* CONFIG_POSIX */ int init_timer_alarm(void) { struct qemu_alarm_timer *t = NULL; int i, err = -1; if (alarm_timer) { return 0; } for (i = 0; alarm_timers[i].name; i++) { t = &alarm_timers[i]; err = t->start(t); if (!err) break; } if (err) { err = -ENOENT; goto fail; } atexit(quit_timers); #ifdef CONFIG_POSIX pthread_atfork(NULL, NULL, reinit_timers); #endif alarm_timer = t; return 0; fail: return err; }