KVM: PIT: remove usage of count_load_time for channel 0 (fd668423) · Commits · 戴 / test

arch/x86/kvm/i8254.c

+31 −6

Original line number	Diff line number	Diff line
		@@ -98,6 +98,32 @@ static int pit_get_gate(struct kvm *kvm, int channel)
		return kvm->arch.vpit->pit_state.channels[channel].gate;
		}

		static s64 __kpit_elapsed(struct kvm *kvm)
		{
		s64 elapsed;
		ktime_t remaining;
		struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;

		remaining = hrtimer_expires_remaining(&ps->pit_timer.timer);
		if (ktime_to_ns(remaining) < 0)
		remaining = ktime_set(0, 0);

		elapsed = ps->pit_timer.period;
		if (ktime_to_ns(remaining) <= ps->pit_timer.period)
		elapsed = ps->pit_timer.period - ktime_to_ns(remaining);

		return elapsed;
		}

		static s64 kpit_elapsed(struct kvm kvm, struct kvm_kpit_channel_state c,
		int channel)
		{
		if (channel == 0)
		return __kpit_elapsed(kvm);

		return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
		}

		static int pit_get_count(struct kvm *kvm, int channel)
		{
		struct kvm_kpit_channel_state *c =
		@@ -107,7 +133,7 @@ static int pit_get_count(struct kvm *kvm, int channel)

		WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));

		t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
		t = kpit_elapsed(kvm, c, channel);
		d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);

		switch (c->mode) {
		@@ -137,7 +163,7 @@ static int pit_get_out(struct kvm *kvm, int channel)

		WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));

		t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
		t = kpit_elapsed(kvm, c, channel);
		d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);

		switch (c->mode) {
		@@ -208,8 +234,6 @@ static int __pit_timer_fn(struct kvm_kpit_state *ps)
		wake_up_interruptible(&vcpu0->wq);

		hrtimer_add_expires_ns(&pt->timer, pt->period);
		if (pt->period)
		ps->channels[0].count_load_time = ktime_get();

		return (pt->period == 0 ? 0 : 1);
		}
		@@ -305,11 +329,12 @@ static void pit_load_count(struct kvm *kvm, int channel, u32 val)
		if (val == 0)
		val = 0x10000;

		ps->channels[channel].count_load_time = ktime_get();
		ps->channels[channel].count = val;

		if (channel != 0)
		if (channel != 0) {
		ps->channels[channel].count_load_time = ktime_get();
		return;
		}

		/* Two types of timer
		* mode 1 is one shot, mode 2 is period, otherwise del timer */

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