diff options
Diffstat (limited to 'qemu-timer.c')
| -rw-r--r-- | qemu-timer.c | 77 |
1 files changed, 64 insertions, 13 deletions
diff --git a/qemu-timer.c b/qemu-timer.c index 72066c7c50..30e8f1272e 100644 --- a/qemu-timer.c +++ b/qemu-timer.c @@ -150,6 +150,9 @@ struct QEMUClock { int enabled; QEMUTimer *warp_timer; + + NotifierList reset_notifiers; + int64_t last; }; struct QEMUTimer { @@ -218,6 +221,7 @@ static void win32_rearm_timer(struct qemu_alarm_timer *t); 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); #ifdef __linux__ @@ -290,7 +294,7 @@ static struct qemu_alarm_timer alarm_timers[] = { {"dynticks", dynticks_start_timer, dynticks_stop_timer, dynticks_rearm_timer}, #endif - {"unix", unix_start_timer, unix_stop_timer, NULL}, + {"unix", unix_start_timer, unix_stop_timer, unix_rearm_timer}, #else {"mmtimer", mm_start_timer, mm_stop_timer, NULL}, {"mmtimer2", mm_start_timer, mm_stop_timer, mm_rearm_timer}, @@ -375,9 +379,15 @@ static QEMUTimer *active_timers[QEMU_NUM_CLOCKS]; static QEMUClock *qemu_new_clock(int type) { QEMUClock *clock; + clock = qemu_mallocz(sizeof(QEMUClock)); clock->type = type; clock->enabled = 1; + notifier_list_init(&clock->reset_notifiers); + /* required to detect & report backward jumps */ + if (type == QEMU_CLOCK_HOST) { + clock->last = get_clock_realtime(); + } return clock; } @@ -592,6 +602,8 @@ static void qemu_run_timers(QEMUClock *clock) int64_t qemu_get_clock_ns(QEMUClock *clock) { + int64_t now, last; + switch(clock->type) { case QEMU_CLOCK_REALTIME: return get_clock(); @@ -603,10 +615,26 @@ int64_t qemu_get_clock_ns(QEMUClock *clock) return cpu_get_clock(); } case QEMU_CLOCK_HOST: - return get_clock_realtime(); + 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_list_remove(&clock->reset_notifiers, notifier); +} + void init_clocks(void) { rt_clock = qemu_new_clock(QEMU_CLOCK_REALTIME); @@ -803,6 +831,8 @@ static int64_t qemu_next_alarm_deadline(void) #if defined(__linux__) +#include "compatfd.h" + static int dynticks_start_timer(struct qemu_alarm_timer *t) { struct sigevent ev; @@ -822,6 +852,12 @@ static int dynticks_start_timer(struct qemu_alarm_timer *t) memset(&ev, 0, sizeof(ev)); ev.sigev_value.sival_int = 0; ev.sigev_notify = SIGEV_SIGNAL; +#ifdef SIGEV_THREAD_ID + if (qemu_signalfd_available()) { + ev.sigev_notify = SIGEV_THREAD_ID; + ev._sigev_un._tid = qemu_get_thread_id(); + } +#endif /* SIGEV_THREAD_ID */ ev.sigev_signo = SIGALRM; if (timer_create(CLOCK_REALTIME, &ev, &host_timer)) { @@ -890,8 +926,6 @@ static void dynticks_rearm_timer(struct qemu_alarm_timer *t) static int unix_start_timer(struct qemu_alarm_timer *t) { struct sigaction act; - struct itimerval itv; - int err; /* timer signal */ sigfillset(&act.sa_mask); @@ -899,18 +933,35 @@ static int unix_start_timer(struct qemu_alarm_timer *t) act.sa_handler = host_alarm_handler; sigaction(SIGALRM, &act, NULL); + return 0; +} - itv.it_interval.tv_sec = 0; - /* for i386 kernel 2.6 to get 1 ms */ - itv.it_interval.tv_usec = 999; - itv.it_value.tv_sec = 0; - itv.it_value.tv_usec = 10 * 1000; +static void unix_rearm_timer(struct qemu_alarm_timer *t) +{ + struct itimerval itv; + int64_t nearest_delta_ns = INT64_MAX; + int err; - err = setitimer(ITIMER_REAL, &itv, NULL); - if (err) - return -1; + assert(alarm_has_dynticks(t)); + if (!active_timers[QEMU_CLOCK_REALTIME] && + !active_timers[QEMU_CLOCK_VIRTUAL] && + !active_timers[QEMU_CLOCK_HOST]) + return; - return 0; + nearest_delta_ns = qemu_next_alarm_deadline(); + 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) |