On 21/06/19 11:40, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
>
> already-expired timer interrupt can be injected to guest when vCPU who
> arms the lapic timer re-vmentry, don't posted inject in this case.
>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx>
> Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
> Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
> ---
> arch/x86/kvm/lapic.c | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index ae575c0..7cd95ea 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -1452,7 +1452,7 @@ static void kvm_apic_inject_pending_timer_irqs(struct kvm_lapic *apic)
> }
> }
>
> -static void apic_timer_expired(struct kvm_lapic *apic)
> +static void apic_timer_expired(struct kvm_lapic *apic, bool can_pi_inject)
> {
> struct kvm_vcpu *vcpu = apic->vcpu;
> struct swait_queue_head *q = &vcpu->wq;
> @@ -1464,7 +1464,7 @@ static void apic_timer_expired(struct kvm_lapic *apic)
> if (apic_lvtt_tscdeadline(apic) || ktimer->hv_timer_in_use)
> ktimer->expired_tscdeadline = ktimer->tscdeadline;
>
> - if (posted_interrupt_inject_timer(apic->vcpu)) {
> + if (can_pi_inject && posted_interrupt_inject_timer(apic->vcpu)) {
Perhaps it should use a posted interrupt if kvm_arch_should_kick(vcpu),
i.e. just add kvm_arch_vcpu_should_kick(apic->vcpu) to
posted_interrupt_inject_timer?
Paolo
> if (apic->lapic_timer.timer_advance_ns)
> kvm_wait_lapic_expire(vcpu, true);
> kvm_apic_inject_pending_timer_irqs(apic);
> @@ -1607,7 +1607,7 @@ static void start_sw_tscdeadline(struct kvm_lapic *apic)
> expire = ktime_sub_ns(expire, ktimer->timer_advance_ns);
> hrtimer_start(&ktimer->timer, expire, HRTIMER_MODE_ABS);
> } else
> - apic_timer_expired(apic);
> + apic_timer_expired(apic, false);
>
> local_irq_restore(flags);
> }
> @@ -1697,7 +1697,7 @@ static void start_sw_period(struct kvm_lapic *apic)
>
> if (ktime_after(ktime_get(),
> apic->lapic_timer.target_expiration)) {
> - apic_timer_expired(apic);
> + apic_timer_expired(apic, false);
>
> if (apic_lvtt_oneshot(apic))
> return;
> @@ -1759,7 +1759,7 @@ static bool start_hv_timer(struct kvm_lapic *apic)
> if (atomic_read(&ktimer->pending)) {
> cancel_hv_timer(apic);
> } else if (expired) {
> - apic_timer_expired(apic);
> + apic_timer_expired(apic, false);
> cancel_hv_timer(apic);
> }
> }
> @@ -1809,7 +1809,7 @@ void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu)
> goto out;
> WARN_ON(swait_active(&vcpu->wq));
> cancel_hv_timer(apic);
> - apic_timer_expired(apic);
> + apic_timer_expired(apic, false);
>
> if (apic_lvtt_period(apic) && apic->lapic_timer.period) {
> advance_periodic_target_expiration(apic);
> @@ -2312,7 +2312,7 @@ static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
> struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
> struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic, lapic_timer);
>
> - apic_timer_expired(apic);
> + apic_timer_expired(apic, true);
>
> if (lapic_is_periodic(apic)) {
> advance_periodic_target_expiration(apic);
>
