Re: [PATCH v2 5/5] KVM: VMX: Handle preemption timer fastpath

From: Wanpeng Li
Date: Thu Apr 23 2020 - 05:57:06 EST


On Thu, 23 Apr 2020 at 17:40, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
>
> On 23/04/20 11:01, Wanpeng Li wrote:
> > +bool kvm_lapic_expired_hv_timer_fast(struct kvm_vcpu *vcpu)
> > +{
> > + struct kvm_lapic *apic = vcpu->arch.apic;
> > + struct kvm_timer *ktimer = &apic->lapic_timer;
> > +
> > + if (!apic_lvtt_tscdeadline(apic) ||
> > + !ktimer->hv_timer_in_use ||
> > + atomic_read(&ktimer->pending))
> > + return 0;
> > +
> > + WARN_ON(swait_active(&vcpu->wq));
> > + cancel_hv_timer(apic);
> > +
> > + ktimer->expired_tscdeadline = ktimer->tscdeadline;
> > + kvm_inject_apic_timer_irqs_fast(vcpu);
> > +
> > + return 1;
> > +}
> > +EXPORT_SYMBOL_GPL(kvm_lapic_expired_hv_timer_fast);
>
> Please re-evaluate if this is needed (or which parts are needed) after
> cleaning up patch 4. Anyway again---this is already better, I don't
> like the duplicated code but at least I can understand what's going on.

Except the apic_lvtt_tscdeadline(apic) check, others are duplicated,
what do you think about apic_lvtt_tscdeadline(apic) check?

Wanpeng