From b99dc0d1a4d395bad649ef25abe21c5f076787a5 Mon Sep 17 00:00:00 2001 From: balrog Date: Sun, 16 Dec 2007 13:17:12 +0000 Subject: [PATCH] Redundant timer rearm optimisation by Anders Melchiorsen. git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3823 c046a42c-6fe2-441c-8c8c-71466251a162 --- vl.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/vl.c b/vl.c index 2ed3254345..a1616cf9cf 100644 --- a/vl.c +++ b/vl.c @@ -822,6 +822,7 @@ struct qemu_alarm_timer { }; #define ALARM_FLAG_DYNTICKS 0x1 +#define ALARM_FLAG_MODIFIED 0x2 static inline int alarm_has_dynticks(struct qemu_alarm_timer *t) { @@ -833,6 +834,11 @@ static void qemu_rearm_alarm_timer(struct qemu_alarm_timer *t) if (!alarm_has_dynticks(t)) return; + if (!(t->flags & ALARM_FLAG_MODIFIED)) + return; + + t->flags &= ~(ALARM_FLAG_MODIFIED); + t->rearm(t); } @@ -995,6 +1001,8 @@ void qemu_del_timer(QEMUTimer *ts) { QEMUTimer **pt, *t; + alarm_timer->flags |= ALARM_FLAG_MODIFIED; + /* NOTE: this code must be signal safe because qemu_timer_expired() can be called from a signal. */ pt = &active_timers[ts->clock->type]; @@ -1067,7 +1075,6 @@ static void qemu_run_timers(QEMUTimer **ptimer_head, int64_t current_time) /* run the callback (the timer list can be modified) */ ts->cb(ts->opaque); } - qemu_rearm_alarm_timer(alarm_timer); } int64_t qemu_get_clock(QEMUClock *clock) @@ -1187,6 +1194,7 @@ static void host_alarm_handler(int host_signum) CPUState *env = next_cpu; if (env) { + alarm_timer->flags |= ALARM_FLAG_MODIFIED; /* stop the currently executing cpu because a timer occured */ cpu_interrupt(env, CPU_INTERRUPT_EXIT); #ifdef USE_KQEMU @@ -7364,6 +7372,8 @@ void main_loop_wait(int timeout) qemu_run_timers(&active_timers[QEMU_TIMER_REALTIME], qemu_get_clock(rt_clock)); + qemu_rearm_alarm_timer(alarm_timer); + /* Check bottom-halves last in case any of the earlier events triggered them. */ qemu_bh_poll(); -- 2.11.0