add a generic scaling mechanism for timers

This enables rt_clock timers to use nanosecond resolution, just by
using the _ns functions; there is really no reason to forbid that.

Migrated timers are all using vm_clock (of course; but I checked that
anyway) so the timers in the savevm files are already in nanosecond
resolution.  So this patch makes no change to the migration format.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2011-03-11 16:33:58 +01:00
parent 7447545544
commit 4a998740b2
2 changed files with 21 additions and 13 deletions

View File

@ -153,12 +153,12 @@ void cpu_disable_ticks(void)
struct QEMUClock {
int type;
int enabled;
/* XXX: add frequency */
};
struct QEMUTimer {
QEMUClock *clock;
int64_t expire_time;
int64_t expire_time; /* in nanoseconds */
int scale;
QEMUTimerCB *cb;
void *opaque;
struct QEMUTimer *next;
@ -386,7 +386,8 @@ void qemu_clock_enable(QEMUClock *clock, int enabled)
clock->enabled = enabled;
}
QEMUTimer *qemu_new_timer(QEMUClock *clock, QEMUTimerCB *cb, void *opaque)
QEMUTimer *qemu_new_timer(QEMUClock *clock, int scale,
QEMUTimerCB *cb, void *opaque)
{
QEMUTimer *ts;
@ -394,6 +395,7 @@ QEMUTimer *qemu_new_timer(QEMUClock *clock, QEMUTimerCB *cb, void *opaque)
ts->clock = clock;
ts->cb = cb;
ts->opaque = opaque;
ts->scale = scale;
return ts;
}
@ -424,7 +426,7 @@ void qemu_del_timer(QEMUTimer *ts)
/* 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(QEMUTimer *ts, int64_t expire_time)
static void qemu_mod_timer_ns(QEMUTimer *ts, int64_t expire_time)
{
QEMUTimer **pt, *t;
@ -457,6 +459,13 @@ void qemu_mod_timer(QEMUTimer *ts, int64_t expire_time)
}
}
/* 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(QEMUTimer *ts, int64_t expire_time)
{
qemu_mod_timer_ns(ts, expire_time * ts->scale);
}
int qemu_timer_pending(QEMUTimer *ts)
{
QEMUTimer *t;
@ -471,7 +480,7 @@ int qemu_timer_expired(QEMUTimer *timer_head, int64_t current_time)
{
if (!timer_head)
return 0;
return (timer_head->expire_time <= current_time);
return (timer_head->expire_time <= current_time * timer_head->scale);
}
static void qemu_run_timers(QEMUClock *clock)
@ -482,7 +491,7 @@ static void qemu_run_timers(QEMUClock *clock)
if (!clock->enabled)
return;
current_time = qemu_get_clock (clock);
current_time = qemu_get_clock_ns(clock);
ptimer_head = &active_timers[clock->type];
for(;;) {
ts = *ptimer_head;
@ -559,7 +568,7 @@ void qemu_get_timer(QEMUFile *f, QEMUTimer *ts)
expire_time = qemu_get_be64(f);
if (expire_time != -1) {
qemu_mod_timer(ts, expire_time);
qemu_mod_timer_ns(ts, expire_time);
} else {
qemu_del_timer(ts);
}
@ -717,7 +726,7 @@ static int64_t qemu_next_alarm_deadline(void)
delta = hdelta;
}
if (active_timers[QEMU_CLOCK_REALTIME]) {
rtdelta = (active_timers[QEMU_CLOCK_REALTIME]->expire_time * 1000000 -
rtdelta = (active_timers[QEMU_CLOCK_REALTIME]->expire_time -
qemu_get_clock_ns(rt_clock));
if (rtdelta < delta)
delta = rtdelta;

View File

@ -41,7 +41,8 @@ int64_t qemu_get_clock(QEMUClock *clock);
int64_t qemu_get_clock_ns(QEMUClock *clock);
void qemu_clock_enable(QEMUClock *clock, int enabled);
QEMUTimer *qemu_new_timer(QEMUClock *clock, QEMUTimerCB *cb, void *opaque);
QEMUTimer *qemu_new_timer(QEMUClock *clock, int scale,
QEMUTimerCB *cb, void *opaque);
void qemu_free_timer(QEMUTimer *ts);
void qemu_del_timer(QEMUTimer *ts);
void qemu_mod_timer(QEMUTimer *ts, int64_t expire_time);
@ -61,15 +62,13 @@ void quit_timers(void);
static inline QEMUTimer *qemu_new_timer_ns(QEMUClock *clock, QEMUTimerCB *cb,
void *opaque)
{
assert(clock != rt_clock);
return qemu_new_timer(clock, cb, opaque);
return qemu_new_timer(clock, SCALE_NS, cb, opaque);
}
static inline QEMUTimer *qemu_new_timer_ms(QEMUClock *clock, QEMUTimerCB *cb,
void *opaque)
{
assert(clock == rt_clock);
return qemu_new_timer(clock, cb, opaque);
return qemu_new_timer(clock, SCALE_MS, cb, opaque);
}
static inline int64_t qemu_get_clock_ms(QEMUClock *clock)