Re: [PATCH v3 3/4] KVM: x86: Add EOI exit bitmap inference

[Paolo Bonzini <pbonzini@redhat.com>]

On 03/06/2015 01:51, Steve Rutherford wrote:
> +static inline void kvm_arch_irq_routing_update(struct kvm *kvm)
> +{
> +}

Please add the static inline to all arches instead of putting it in
#ifndef __KVM_HAVE_IOAPIC.  It's not related to the existence of an ioapic.

> 
> +void kvm_arch_irq_routing_update(struct kvm *kvm)
> +{
> +	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
> +
> +	if (ioapic)
> +		return;
> +	if (!lapic_in_kernel(kvm))
> +		return;
> +	kvm_make_scan_ioapic_request(kvm);
> +}
> +

It's weird to have a function in ioapic.c that only does something if
you _do not_ have an ioapic. :)

> +
> +void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)

This must stay in arch/x86/kvm/.  I'd put both of these in irq_comm.c.

Then you do not need kvm_arch_nr_userspace_ioapic_pins anymore.

Paolo

> +{
> +	struct kvm *kvm = vcpu->kvm;
> +	struct kvm_kernel_irq_routing_entry *entry;
> +	struct kvm_irq_routing_table *table;
> +	u32 i, nr_ioapic_pins;
> +	int idx;
> +
> +	/* kvm->irq_routing must be read after clearing
> +	 * KVM_SCAN_IOAPIC. */
> +	smp_mb();
> +	idx = srcu_read_lock(&kvm->irq_srcu);
> +	table = kvm->irq_routing;
> +	nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
> +			      kvm_arch_nr_userspace_ioapic_pins(kvm));
> +	for (i = 0; i < nr_ioapic_pins; ++i) {
> +		hlist_for_each_entry(entry, &table->map[i], link) {
> +			u32 dest_id, dest_mode;
> +
> +			if (entry->type != KVM_IRQ_ROUTING_MSI)
> +				continue;
> +			dest_id = (entry->msi.address_lo >> 12) & 0xff;
> +			dest_mode = (entry->msi.address_lo >> 2) & 0x1;
> +			if (kvm_apic_match_dest(vcpu, NULL, 0, dest_id,
> +						dest_mode)) {
> +				u32 vector = entry->msi.data & 0xff;
> +
> +				__set_bit(vector,
> +					  (unsigned long *) eoi_exit_bitmap);
> +			}
> +		}
> +	}
> +	srcu_read_unlock(&kvm->irq_srcu, idx);
> +}