Re: [RFC PATCH 2/2] Cache msi irq destination.

[Avi Kivity <avi@redhat.com>]

On 08/13/2012 12:16 PM, Gleb Natapov wrote:
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
>  
> -int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
> +int kvm_irq_delivery_to_apic(struct kvm_kernel_irq_routing_entry *e,
> +		struct kvm *kvm, struct kvm_lapic *src,
>  		struct kvm_lapic_irq *irq)

Would be nicer to put e at the end, and explain that it is optional.

>  {
> -	int i, r = -1;
> -	struct kvm_vcpu *vcpu, *lowest = NULL;
> +	int i, r = -1, c = 0;
> +	struct kvm_vcpu *vcpu, *cache = NULL, *lowest = NULL;
>  
>  	if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
>  			kvm_is_dm_lowest_prio(irq))
> @@ -82,6 +83,8 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
>  		if (!kvm_is_dm_lowest_prio(irq)) {
>  			if (r < 0)
>  				r = 0;
> +			c++;
> +			cache = vcpu;
>  			r += kvm_apic_set_irq(vcpu, irq);
>  		} else if (kvm_lapic_enabled(vcpu)) {
>  			if (!lowest)
> @@ -93,6 +96,8 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
>  
>  	if (lowest)
>  		r = kvm_apic_set_irq(lowest, irq);
> +	else if (e && c == 1)
> +		e->vcpu = cache; /* cache it */
>  
>  	return r;
>  }
> @@ -118,7 +123,9 @@ int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
>  	irq.shorthand = 0;
>  
>  	/* TODO Deal with RH bit of MSI message address */
> -	return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
> +	if (e->vcpu)
> +		return kvm_apic_set_irq(e->vcpu, &irq);
> +	return kvm_irq_delivery_to_apic(e, kvm, NULL, &irq);
>  }
>  
>  int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
> @@ -131,6 +138,7 @@ int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
>  	route.msi.address_lo = msi->address_lo;
>  	route.msi.address_hi = msi->address_hi;
>  	route.msi.data = msi->data;
> +	route.vcpu = NULL;
>  
>  	return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1);
>  }
> 

Missing cache invalidate on apicid write?

Otherwise nice and simple.


-- 
error compiling committee.c: too many arguments to function