Exemple #1
0
/* Measure RTT for each ack. */
static void tcp_illinois_acked(struct sock *sk, u32 pkts_acked, ktime_t last)
{
	struct illinois *ca = inet_csk_ca(sk);
	u32 rtt;

	ca->acked = pkts_acked;

	if (ktime_equal(last, net_invalid_timestamp()))
		return;

	rtt = ktime_to_us(net_timedelta(last));

	/* ignore bogus values, this prevents wraparound in alpha math */
	if (rtt > RTT_MAX)
		rtt = RTT_MAX;

	/* keep track of minimum RTT seen so far */
	if (ca->base_rtt > rtt)
		ca->base_rtt = rtt;

	/* and max */
	if (ca->max_rtt < rtt)
		ca->max_rtt = rtt;

	++ca->cnt_rtt;
	ca->sum_rtt += rtt;
}
static ssize_t vsync_show_event(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	int cndx;
	struct vsycn_ctrl *vctrl;
	ssize_t ret = 0;
	u64 vsync_tick;
	ktime_t timestamp;

	cndx = 0;
	vctrl = &vsync_ctrl_db[0];
	timestamp = vctrl->vsync_time;

	ret = wait_event_interruptible_timeout(vctrl->wait_queue,
			!ktime_equal(timestamp, vctrl->vsync_time) &&
			vctrl->vsync_irq_enabled, msecs_to_jiffies(VSYNC_PERIOD * 4));
	if (ret == -ERESTARTSYS)
		return ret;
	else if (ret == 0)
		vsync_tick = ktime_to_ns(ktime_get());
	else
		vsync_tick = ktime_to_ns(vctrl->vsync_time);

	ret = scnprintf(buf, PAGE_SIZE, "VSYNC=%llu", vsync_tick);
	buf[strlen(buf) + 1] = '\0';
	return ret;
}
ssize_t mdp4_dsi_video_show_event(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	int cndx;
	struct vsycn_ctrl *vctrl;
	ssize_t ret = 0;
	u64 vsync_tick;
	ktime_t timestamp;

	cndx = 0;
	vctrl = &vsync_ctrl_db[0];
	timestamp = vctrl->vsync_time;

	sec_debug_mdp_set_value(SEC_DEBUG_VSYNC_SYSFS_EVENT, SEC_DEBUG_IN);
	ret = wait_event_interruptible(vctrl->wait_queue,
			!ktime_equal(timestamp, vctrl->vsync_time) &&
			vctrl->vsync_irq_enabled);
	if (ret == -ERESTARTSYS)
		return ret;

	vsync_tick = ktime_to_ns(vctrl->vsync_time);
	ret = scnprintf(buf, PAGE_SIZE, "VSYNC=%llu", vsync_tick);
	buf[strlen(buf) + 1] = '\0';
	sec_debug_mdp_set_value(SEC_DEBUG_VSYNC_SYSFS_EVENT, SEC_DEBUG_OUT);
	return ret;
}
void mdp4_dsi_video_wait4vsync(int cndx)
{
	struct vsycn_ctrl *vctrl;
	int ret;
	ktime_t timestamp;
	unsigned long flags;

	if (cndx >= MAX_CONTROLLER) {
		pr_err("%s: out or range: cndx=%d\n", __func__, cndx);
		return;
	}

	vctrl = &vsync_ctrl_db[cndx];
	if (atomic_read(&vctrl->suspend) > 0)
		return;
	spin_lock_irqsave(&vctrl->spin_lock, flags);
	timestamp = vctrl->vsync_time;
	spin_unlock_irqrestore(&vctrl->spin_lock, flags);

	mdp4_video_vsync_irq_ctrl(cndx, 1);

	ret = wait_event_timeout(vctrl->wait_queue_internal,
			!ktime_equal(timestamp, vctrl->vsync_time),
			msecs_to_jiffies(VSYNC_PERIOD * 8));

	if (ret <= 0)
		pr_err("%s timeout ret=%d", __func__, ret);

	mdp4_video_vsync_irq_ctrl(cndx, 0);
	mdp4_stat.wait4vsync0++;
}
void mdp4_dsi_video_wait4vsync(int cndx)
{
	struct vsycn_ctrl *vctrl;
	struct mdp4_overlay_pipe *pipe;
	int ret;
	ktime_t timestamp;

	if (cndx >= MAX_CONTROLLER) {
		pr_err("%s: out or range: cndx=%d\n", __func__, cndx);
		return;
	}

	vctrl = &vsync_ctrl_db[cndx];
	pipe = vctrl->base_pipe;

	if (atomic_read(&vctrl->suspend) > 0)
		return;

	mdp4_video_vsync_irq_ctrl(cndx, 1);

	timestamp = vctrl->vsync_time;
	ret = wait_event_interruptible_timeout(vctrl->wait_queue,
			!ktime_equal(timestamp, vctrl->vsync_time)&&
			vctrl->vsync_irq_enabled,
			msecs_to_jiffies(VSYNC_PERIOD * 8));

	if (ret <= 0)
		pr_err("%s timeout ret=%d", __func__, ret);

	mdp4_video_vsync_irq_ctrl(cndx, 0);
	mdp4_stat.wait4vsync0++;
}
ssize_t mdp4_dsi_video_show_event(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	int cndx;
	struct vsycn_ctrl *vctrl;
	ssize_t ret = 0;
	u64 vsync_tick;
	ktime_t timestamp;
	unsigned long flags;

	cndx = 0;
	vctrl = &vsync_ctrl_db[0];

	spin_lock_irqsave(&vctrl->spin_lock, flags);
	timestamp = vctrl->vsync_time;
	spin_unlock_irqrestore(&vctrl->spin_lock, flags);

	ret = wait_event_interruptible(vctrl->wait_queue,
			!ktime_equal(timestamp, vctrl->vsync_time) &&
			vctrl->vsync_irq_enabled);
	if (ret == -ERESTARTSYS)
		return ret;

	spin_lock_irqsave(&vctrl->spin_lock, flags);
	vsync_tick = ktime_to_ns(vctrl->vsync_time);
	spin_unlock_irqrestore(&vctrl->spin_lock, flags);

	ret = scnprintf(buf, PAGE_SIZE, "VSYNC=%llu", vsync_tick);
	buf[strlen(buf) + 1] = '\0';
	return ret;
}
int mxr_reg_wait4update(struct mxr_device *mdev)
{
	ktime_t timestamp = mdev->vsync_timestamp;
	int ret;

	ret = wait_event_interruptible_timeout(mdev->vsync_wait,
		!ktime_equal(timestamp, mdev->vsync_timestamp)
				&& !mxr_update_pending(mdev),
		msecs_to_jiffies(100));
	if (ret > 0)
		return 0;
	if (ret < 0)
		return ret;
	mxr_warn(mdev, "no vsync detected - timeout\n");
	return -ETIME;
}
Exemple #8
0
/* Do rtt sampling needed for Veno. */
static void tcp_veno_pkts_acked(struct sock *sk, u32 cnt, ktime_t last)
{
    struct veno *veno = inet_csk_ca(sk);
    u32 vrtt;

    if (ktime_equal(last, net_invalid_timestamp()))
        return;

    /* Never allow zero rtt or baseRTT */
    vrtt = ktime_to_us(net_timedelta(last)) + 1;

    /* Filter to find propagation delay: */
    if (vrtt < veno->basertt)
        veno->basertt = vrtt;

    /* Find the min rtt during the last rtt to find
     * the current prop. delay + queuing delay:
     */
    veno->minrtt = min(veno->minrtt, vrtt);
    veno->cntrtt++;
}
Exemple #9
0
/* Do RTT sampling needed for Vegas.
 * Basically we:
 *   o min-filter RTT samples from within an RTT to get the current
 *     propagation delay + queuing delay (we are min-filtering to try to
 *     avoid the effects of delayed ACKs)
 *   o min-filter RTT samples from a much longer window (forever for now)
 *     to find the propagation delay (baseRTT)
 */
void tcp_vegas_pkts_acked(struct sock *sk, u32 cnt, ktime_t last)
{
	cnt = cnt;

	struct vegas *vegas = inet_csk_ca(sk);
	u32 vrtt;

	if (ktime_equal(last, net_invalid_timestamp()))
		return;

	/* Never allow zero rtt or baseRTT */
	vrtt = ktime_to_us(net_timedelta(last)) + 1;

	/* Filter to find propagation delay: */
	if (vrtt < vegas->baseRTT)
		vegas->baseRTT = vrtt;

	/* Find the min RTT during the last RTT to find
	 * the current prop. delay + queuing delay:
	 */
	vegas->minRTT = min(vegas->minRTT, vrtt);
	vegas->cntRTT++;
}
Exemple #10
0
ssize_t mdp4_lcdc_show_event(struct device *dev,
                             struct device_attribute *attr, char *buf)
{
    int cndx;
    struct vsycn_ctrl *vctrl;
    ssize_t ret = 0;
    u64 vsync_tick;
    ktime_t timestamp;

    cndx = 0;
    vctrl = &vsync_ctrl_db[0];
    timestamp = vctrl->vsync_time;

    ret = wait_event_interruptible(vctrl->wait_queue,
                                   !ktime_equal(timestamp, vctrl->vsync_time) &&
                                   vctrl->vsync_irq_enabled);
    if (ret == -ERESTARTSYS)
        return ret;

    vsync_tick = ktime_to_ns(vctrl->vsync_time);
    ret = scnprintf(buf, PAGE_SIZE, "VSYNC=%llu", vsync_tick);
    buf[strlen(buf) + 1] = '\0';
    return ret;
}
/**
 * tick_nohz_stop_sched_tick - stop the idle tick from the idle task
 *
 * When the next event is more than a tick into the future, stop the idle tick
 * Called either from the idle loop or from irq_exit() when an idle period was
 * just interrupted by an interrupt which did not cause a reschedule.
 */
void tick_nohz_stop_sched_tick(int inidle)
{
	unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags;
	struct tick_sched *ts;
	ktime_t last_update, expires, now;
	struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
	u64 time_delta;
	int cpu;

	local_irq_save(flags);

	cpu = smp_processor_id();
	ts = &per_cpu(tick_cpu_sched, cpu);

	/*
	 * Call to tick_nohz_start_idle stops the last_update_time from being
	 * updated. Thus, it must not be called in the event we are called from
	 * irq_exit() with the prior state different than idle.
	 */
	if (!inidle && !ts->inidle)
		goto end;

	/*
	 * Set ts->inidle unconditionally. Even if the system did not
	 * switch to NOHZ mode the cpu frequency governers rely on the
	 * update of the idle time accounting in tick_nohz_start_idle().
	 */
	ts->inidle = 1;

	now = tick_nohz_start_idle(ts);

	/*
	 * If this cpu is offline and it is the one which updates
	 * jiffies, then give up the assignment and let it be taken by
	 * the cpu which runs the tick timer next. If we don't drop
	 * this here the jiffies might be stale and do_timer() never
	 * invoked.
	 */
	if (unlikely(!cpu_online(cpu))) {
		if (cpu == tick_do_timer_cpu)
			tick_do_timer_cpu = TICK_DO_TIMER_NONE;
	}

	if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
		goto end;

	if (need_resched())
		goto end;

	if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
		static int ratelimit;

		if (ratelimit < 10) {
			printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
			       local_softirq_pending());
			ratelimit++;
		}
		goto end;
	}

	ts->idle_calls++;
	/* Read jiffies and the time when jiffies were updated last */
	do {
		seq = read_seqbegin(&xtime_lock);
		last_update = last_jiffies_update;
		last_jiffies = jiffies;

		/*
		 * On SMP we really should only care for the CPU which
		 * has the do_timer duty assigned. All other CPUs can
		 * sleep as long as they want.
		 */
		if (cpu == tick_do_timer_cpu ||
		    tick_do_timer_cpu == TICK_DO_TIMER_NONE)
			time_delta = timekeeping_max_deferment();
		else
			time_delta = KTIME_MAX;
	} while (read_seqretry(&xtime_lock, seq));

	if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu) ||
	    arch_needs_cpu(cpu)) {
		next_jiffies = last_jiffies + 1;
		delta_jiffies = 1;
	} else {
		/* Get the next timer wheel timer */
		next_jiffies = get_next_timer_interrupt(last_jiffies);
		delta_jiffies = next_jiffies - last_jiffies;
	}
	/*
	 * Do not stop the tick, if we are only one off
	 * or if the cpu is required for rcu
	 */
	if (!ts->tick_stopped && delta_jiffies == 1)
		goto out;

	/* Schedule the tick, if we are at least one jiffie off */
	if ((long)delta_jiffies >= 1) {

		/*
		 * calculate the expiry time for the next timer wheel
		 * timer. delta_jiffies >= NEXT_TIMER_MAX_DELTA signals
		 * that there is no timer pending or at least extremely
		 * far into the future (12 days for HZ=1000). In this
		 * case we set the expiry to the end of time.
		 */
		if (likely(delta_jiffies < NEXT_TIMER_MAX_DELTA)) {
			/*
			 * Calculate the time delta for the next timer event.
			 * If the time delta exceeds the maximum time delta
			 * permitted by the current clocksource then adjust
			 * the time delta accordingly to ensure the
			 * clocksource does not wrap.
			 */
			time_delta = min_t(u64, time_delta,
					   tick_period.tv64 * delta_jiffies);
			expires = ktime_add_ns(last_update, time_delta);
		} else {
			expires.tv64 = KTIME_MAX;
		}

		/*
		 * If this cpu is the one which updates jiffies, then
		 * give up the assignment and let it be taken by the
		 * cpu which runs the tick timer next, which might be
		 * this cpu as well. If we don't drop this here the
		 * jiffies might be stale and do_timer() never
		 * invoked.
		 */
		if (cpu == tick_do_timer_cpu)
			tick_do_timer_cpu = TICK_DO_TIMER_NONE;

		if (delta_jiffies > 1)
			cpumask_set_cpu(cpu, nohz_cpu_mask);

		/* Skip reprogram of event if its not changed */
		if (ts->tick_stopped && ktime_equal(expires, dev->next_event))
			goto out;

		/*
		 * nohz_stop_sched_tick can be called several times before
		 * the nohz_restart_sched_tick is called. This happens when
		 * interrupts arrive which do not cause a reschedule. In the
		 * first call we save the current tick time, so we can restart
		 * the scheduler tick in nohz_restart_sched_tick.
		 */
		if (!ts->tick_stopped) {
			if (select_nohz_load_balancer(1)) {
				/*
				 * sched tick not stopped!
				 */
				cpumask_clear_cpu(cpu, nohz_cpu_mask);
				goto out;
			}

			ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
			ts->tick_stopped = 1;
			ts->idle_jiffies = last_jiffies;
			rcu_enter_nohz();
		}

		ts->idle_sleeps++;

		/* Mark expires */
		ts->idle_expires = expires;

		/*
		 * If the expiration time == KTIME_MAX, then
		 * in this case we simply stop the tick timer.
		 */
		 if (unlikely(expires.tv64 == KTIME_MAX)) {
			if (ts->nohz_mode == NOHZ_MODE_HIGHRES)
				hrtimer_cancel(&ts->sched_timer);
			goto out;
		}

		if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
			hrtimer_start(&ts->sched_timer, expires,
				      HRTIMER_MODE_ABS_PINNED);
			/* Check, if the timer was already in the past */
			if (hrtimer_active(&ts->sched_timer))
				goto out;
		} else if (!tick_program_event(expires, 0))
				goto out;
		/*
		 * We are past the event already. So we crossed a
		 * jiffie boundary. Update jiffies and raise the
		 * softirq.
		 */
		tick_do_update_jiffies64(ktime_get());
		cpumask_clear_cpu(cpu, nohz_cpu_mask);
	}
	raise_softirq_irqoff(TIMER_SOFTIRQ);
out:
	ts->next_jiffies = next_jiffies;
	ts->last_jiffies = last_jiffies;
	ts->sleep_length = ktime_sub(dev->next_event, now);
end:
	local_irq_restore(flags);
}
static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
{
	unsigned long seq, last_jiffies, next_jiffies, delta_jiffies;
	unsigned long rcu_delta_jiffies;
	ktime_t last_update, expires, now;
	struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
	u64 time_delta;
	int cpu;

	cpu = smp_processor_id();
	ts = &per_cpu(tick_cpu_sched, cpu);

	now = tick_nohz_start_idle(cpu, ts);

	if (unlikely(!cpu_online(cpu))) {
		if (cpu == tick_do_timer_cpu)
			tick_do_timer_cpu = TICK_DO_TIMER_NONE;
	}

	if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
		return;

	if (need_resched())
		return;

	if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
		static int ratelimit;

		if (ratelimit < 10) {
			printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
			       (unsigned int) local_softirq_pending());
			ratelimit++;
		}
		return;
	}

	ts->idle_calls++;
	
	do {
		seq = read_seqbegin(&xtime_lock);
		last_update = last_jiffies_update;
		last_jiffies = jiffies;
		time_delta = timekeeping_max_deferment();
	} while (read_seqretry(&xtime_lock, seq));

	if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) || printk_needs_cpu(cpu) ||
	    arch_needs_cpu(cpu)) {
		next_jiffies = last_jiffies + 1;
		delta_jiffies = 1;
	} else {
		
		next_jiffies = get_next_timer_interrupt(last_jiffies);
		delta_jiffies = next_jiffies - last_jiffies;
		if (rcu_delta_jiffies < delta_jiffies) {
			next_jiffies = last_jiffies + rcu_delta_jiffies;
			delta_jiffies = rcu_delta_jiffies;
		}
	}
	if (!ts->tick_stopped && delta_jiffies == 1)
		goto out;

	
	if ((long)delta_jiffies >= 1) {

		if (cpu == tick_do_timer_cpu) {
			tick_do_timer_cpu = TICK_DO_TIMER_NONE;
			ts->do_timer_last = 1;
		} else if (tick_do_timer_cpu != TICK_DO_TIMER_NONE) {
			time_delta = KTIME_MAX;
			ts->do_timer_last = 0;
		} else if (!ts->do_timer_last) {
			time_delta = KTIME_MAX;
		}

		if (likely(delta_jiffies < NEXT_TIMER_MAX_DELTA)) {
			time_delta = min_t(u64, time_delta,
					   tick_period.tv64 * delta_jiffies);
		}

		if (time_delta < KTIME_MAX)
			expires = ktime_add_ns(last_update, time_delta);
		else
			expires.tv64 = KTIME_MAX;

		
		if (ts->tick_stopped && ktime_equal(expires, dev->next_event))
			goto out;

		if (!ts->tick_stopped) {
			select_nohz_load_balancer(1);

			ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
			ts->tick_stopped = 1;
			ts->idle_jiffies = last_jiffies;
		}

		ts->idle_sleeps++;

		
		ts->idle_expires = expires;

		 if (unlikely(expires.tv64 == KTIME_MAX)) {
			if (ts->nohz_mode == NOHZ_MODE_HIGHRES)
				hrtimer_cancel(&ts->sched_timer);
			goto out;
		}

		if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
			hrtimer_start(&ts->sched_timer, expires,
				      HRTIMER_MODE_ABS_PINNED);
			
			if (hrtimer_active(&ts->sched_timer))
				goto out;
		} else if (!tick_program_event(expires, 0))
				goto out;
		tick_do_update_jiffies64(ktime_get());
	}
	raise_softirq_irqoff(TIMER_SOFTIRQ);
out:
	ts->next_jiffies = next_jiffies;
	ts->last_jiffies = last_jiffies;
}
Exemple #13
0
static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
{
	unsigned long seq, last_jiffies, next_jiffies, delta_jiffies;
	ktime_t last_update, expires, now;
	struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
	u64 time_delta;
	int cpu;

	cpu = smp_processor_id();
	ts = &per_cpu(tick_cpu_sched, cpu);

	now = tick_nohz_start_idle(cpu, ts);

	/*
	 * If this cpu is offline and it is the one which updates
	 * jiffies, then give up the assignment and let it be taken by
	 * the cpu which runs the tick timer next. If we don't drop
	 * this here the jiffies might be stale and do_timer() never
	 * invoked.
	 */
	if (unlikely(!cpu_online(cpu))) {
		if (cpu == tick_do_timer_cpu)
			tick_do_timer_cpu = TICK_DO_TIMER_NONE;
	}

	if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
		return;

	if (need_resched())
		return;

	if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
		static int ratelimit;

		if (ratelimit < 10) {
			printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
			       (unsigned int) local_softirq_pending());
			ratelimit++;
		}
		return;
	}

	ts->idle_calls++;
	/* Read jiffies and the time when jiffies were updated last */
	do {
		seq = read_seqbegin(&xtime_lock);
		last_update = last_jiffies_update;
		last_jiffies = jiffies;
		time_delta = timekeeping_max_deferment();
	} while (read_seqretry(&xtime_lock, seq));

	if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu) ||
	    arch_needs_cpu(cpu)) {
		next_jiffies = last_jiffies + 1;
		delta_jiffies = 1;
	} else {
		/* Get the next timer wheel timer */
		next_jiffies = get_next_timer_interrupt(last_jiffies);
		delta_jiffies = next_jiffies - last_jiffies;
	}
	/*
	 * Do not stop the tick, if we are only one off
	 * or if the cpu is required for rcu
	 */
	if (!ts->tick_stopped && delta_jiffies == 1)
		goto out;

	/* Schedule the tick, if we are at least one jiffie off */
	if ((long)delta_jiffies >= 1) {

		/*
		 * If this cpu is the one which updates jiffies, then
		 * give up the assignment and let it be taken by the
		 * cpu which runs the tick timer next, which might be
		 * this cpu as well. If we don't drop this here the
		 * jiffies might be stale and do_timer() never
		 * invoked. Keep track of the fact that it was the one
		 * which had the do_timer() duty last. If this cpu is
		 * the one which had the do_timer() duty last, we
		 * limit the sleep time to the timekeeping
		 * max_deferement value which we retrieved
		 * above. Otherwise we can sleep as long as we want.
		 */
		if (cpu == tick_do_timer_cpu) {
			tick_do_timer_cpu = TICK_DO_TIMER_NONE;
			ts->do_timer_last = 1;
		} else if (tick_do_timer_cpu != TICK_DO_TIMER_NONE) {
			time_delta = KTIME_MAX;
			ts->do_timer_last = 0;
		} else if (!ts->do_timer_last) {
			time_delta = KTIME_MAX;
		}

		/*
		 * calculate the expiry time for the next timer wheel
		 * timer. delta_jiffies >= NEXT_TIMER_MAX_DELTA signals
		 * that there is no timer pending or at least extremely
		 * far into the future (12 days for HZ=1000). In this
		 * case we set the expiry to the end of time.
		 */
		if (likely(delta_jiffies < NEXT_TIMER_MAX_DELTA)) {
			/*
			 * Calculate the time delta for the next timer event.
			 * If the time delta exceeds the maximum time delta
			 * permitted by the current clocksource then adjust
			 * the time delta accordingly to ensure the
			 * clocksource does not wrap.
			 */
			time_delta = min_t(u64, time_delta,
					   tick_period.tv64 * delta_jiffies);
		}

		if (time_delta < KTIME_MAX)
			expires = ktime_add_ns(last_update, time_delta);
		else
			expires.tv64 = KTIME_MAX;

		/* Skip reprogram of event if its not changed */
		if (ts->tick_stopped && ktime_equal(expires, dev->next_event))
			goto out;

		/*
		 * nohz_stop_sched_tick can be called several times before
		 * the nohz_restart_sched_tick is called. This happens when
		 * interrupts arrive which do not cause a reschedule. In the
		 * first call we save the current tick time, so we can restart
		 * the scheduler tick in nohz_restart_sched_tick.
		 */
		if (!ts->tick_stopped) {
			select_nohz_load_balancer(1);
			calc_load_enter_idle();

			ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
			ts->tick_stopped = 1;
			ts->idle_jiffies = last_jiffies;
		}

		ts->idle_sleeps++;

		/* Mark expires */
		ts->idle_expires = expires;

		/*
		 * If the expiration time == KTIME_MAX, then
		 * in this case we simply stop the tick timer.
		 */
		 if (unlikely(expires.tv64 == KTIME_MAX)) {
			if (ts->nohz_mode == NOHZ_MODE_HIGHRES)
				hrtimer_cancel(&ts->sched_timer);
			goto out;
		}

		if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
			hrtimer_start(&ts->sched_timer, expires,
				      HRTIMER_MODE_ABS_PINNED);
			/* Check, if the timer was already in the past */
			if (hrtimer_active(&ts->sched_timer))
				goto out;
		} else if (!tick_program_event(expires, 0))
				goto out;
		/*
		 * We are past the event already. So we crossed a
		 * jiffie boundary. Update jiffies and raise the
		 * softirq.
		 */
		tick_do_update_jiffies64(ktime_get());
	}
	raise_softirq_irqoff(TIMER_SOFTIRQ);
out:
	ts->next_jiffies = next_jiffies;
	ts->last_jiffies = last_jiffies;
}
static int vsync_timestamp_changed(struct hisi_fb_data_type *hisifd,
	ktime_t prev_timestamp)
{
	BUG_ON(hisifd == NULL);
	return !ktime_equal(prev_timestamp, hisifd->vsync_ctrl.vsync_timestamp);
}
Exemple #15
0
static int s3cfb_vsync_timestamp_changed(struct s3cfb_global *fbdev,
		ktime_t prev_timestamp)
{
	rmb();
	return !ktime_equal(prev_timestamp, fbdev->vsync_timestamp);
}
/* Do RTT sampling needed for Vegas.
 * Basically we:
 *   o min-filter RTT samples from within an RTT to get the current
 *     propagation delay + queuing delay (we are min-filtering to try to
 *     avoid the effects of delayed ACKs)
 *   o min-filter RTT samples from a much longer window (forever for now)
 *     to find the propagation delay (baseRTT)
 */
void tcp_sod_delay_pkts_acked(struct sock *sk, u32 cnt, ktime_t last)
{
	struct tcp_sock *tp = tcp_sk(sk);
	struct sod_delay *sod = inet_csk_ca(sk);
	u64 vrtt;
	u64 qd_plus_td, remain_qd;
	u16 est_ql = 0;

	if (ktime_equal(last, net_invalid_timestamp()))
		return;

	/* Never allow zero rtt or baseRTT */
	vrtt = ktime_to_us(net_timedelta(last)) + 1;

	/* Filter to find propagation delay: */
	if (vrtt < sod->baseRTT)
		sod->baseRTT = vrtt;
	
	qd_plus_td = vrtt - sod->baseRTT;
	if (tp->td_last_index == 0)
		est_ql = 0;
	else
	{
		if (qd_plus_td < tp->ary_td[tp->td_last_index -1].td_i)
			est_ql = 1;
		else
		{
			u32 td_index = tp->td_last_index -1;
			remain_qd = qd_plus_td - tp->ary_td[td_index].td_i;
			while (remain_qd > 0 && td_index != tp->td_head_index)
			{
				if (tp->td_head_index >= tp->td_last_index && td_index == 0 )
				{
					if (tp->td_count > 1)
						td_index = tp->td_count -1;
					else break;
				}
				else td_index--;
				
				if (remain_qd > tp->ary_td[td_index].td_i)
				{
					remain_qd -= tp->ary_td[td_index].td_i;
					est_ql++;
				}
				else 
				{
					est_ql++;
					break;
				}
			}
			est_ql++;
		}
	}
	sod->curQL = est_ql;
	sod->minQL = min(sod->minQL, est_ql);
	//printf("current estimation: %lu\n", sod->curQL);
	/* Find the min RTT during the last RTT to find
	 * the current prop. delay + queuing delay:
	 */
	sod->minRTT = min(sod->minRTT, vrtt);
	sod->cntRTT++;
}