Re: [PATCH 1/2] KVM: x86: Simplify __apic_accept_irq

Gleb Natapov
2013-07-25T10:44:30Z

On Thu, Jul 25, 2013 at 09:58:45AM +0200, Jan Kiszka wrote:
> If posted interrupts are enabled, we can no longer track if an IRQ was
> coalesced based on IRR. So drop this logic also from the classic
> software path and simplify apic_test_and_set_irr to apic_set_irr.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Applied both, thanks.

> ---
> arch/x86/kvm/lapic.c | 23 ++++++++---------------
> 1 files changed, 8 insertions(+), 15 deletions(-)
>
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index afc1124..9dc3650 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -331,10 +331,10 @@ void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir)
> }
> EXPORT_SYMBOL_GPL(kvm_apic_update_irr);
>
> -static inline int apic_test_and_set_irr(int vec, struct kvm_lapic *apic)
> +static inline void apic_set_irr(int vec, struct kvm_lapic *apic)
> {
> apic->irr_pending = true;
> - return apic_test_and_set_vector(vec, apic->regs + APIC_IRR);
> + apic_set_vector(vec, apic->regs + APIC_IRR);
> }
>
> static inline int apic_search_irr(struct kvm_lapic *apic)
> @@ -681,28 +681,21 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
> if (unlikely(!apic_enabled(apic)))
> break;
>
> + result = 1;
> +
> if (dest_map)
> __set_bit(vcpu->vcpu_id, dest_map);
>
> - if (kvm_x86_ops->deliver_posted_interrupt) {
> - result = 1;
> + if (kvm_x86_ops->deliver_posted_interrupt)
> kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
> - } else {
> - result = !apic_test_and_set_irr(vector, apic);
> -
> - if (!result) {
> - if (trig_mode)
> - apic_debug("level trig mode repeatedly "
> - "for vector %d", vector);
> - goto out;
> - }
> + else {
> + apic_set_irr(vector, apic);
>
> kvm_make_request(KVM_REQ_EVENT, vcpu);
> kvm_vcpu_kick(vcpu);
> }
> -out:
> trace_kvm_apic_accept_irq(vcpu->vcpu_id, delivery_mode,
> - trig_mode, vector, !result);
> + trig_mode, vector, false);
> break;
>
> case APIC_DM_REMRD:
> --
> 1.7.3.4

--
Gleb.