On 06/03/2017 14:17, David Hildenbrand wrote:
> KVM_IRQCHIP_NONE,
> + KVM_IRQCHIP_KERNEL_INIT, /* KVM_CREATE_IRQCHIP in progress */
Maybe KVM_IRQCHIP_INIT_IN_PROGRESS?
> - bool ret = kvm->arch.irqchip_mode != KVM_IRQCHIP_NONE;
> + bool ret = kvm->arch.irqchip_mode == KVM_IRQCHIP_KERNEL ||
> + kvm->arch.irqchip_mode == KVM_IRQCHIP_SPLIT;
I suspect that if you phrase it the other way round (!= NONE && !=
KERNEL_INIT) you'll get infinitesimally better code, because it can be
compiled to an unsigned comparison with 1.
> /* Matches with wmb after initializing kvm->irq_routing. */
> smp_rmb();
> diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
> index b96d389..4e4a67a 100644
> --- a/arch/x86/kvm/irq_comm.c
> +++ b/arch/x86/kvm/irq_comm.c
> @@ -282,22 +282,18 @@ int kvm_set_routing_entry(struct kvm *kvm,
>
> switch (ue->type) {
> case KVM_IRQ_ROUTING_IRQCHIP:
> + if (!irqchip_kernel(kvm) && !irqchip_kernel_init(kvm))
> + goto out;
> delta = 0;
This can be irqchip_in_kernel, after which irqchip_kernel_init can be
removed.
Should the code to enable split irqchip also use KVM_IRQCHIP_KERNEL_INIT?
Paolo
