Re: [PATCH v4 2/2] KVM: LAPIC: micro-optimize fixed mode ipi delivery

From: Paolo Bonzini
Date: Wed Jan 15 2020 - 12:51:34 EST


On 21/11/19 04:17, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
>
> This patch optimizes redundancy logic before fixed mode ipi is delivered
> in the fast path, broadcast handling needs to go slow path, so the delivery
> mode repair can be delayed to before slow path.
>
> Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
> ---
> arch/x86/kvm/irq_comm.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
> index 8ecd48d..aa88156 100644
> --- a/arch/x86/kvm/irq_comm.c
> +++ b/arch/x86/kvm/irq_comm.c
> @@ -52,15 +52,15 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
> unsigned long dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
> unsigned int dest_vcpus = 0;
>
> + if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
> + return r;
> +
> if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
> kvm_lowest_prio_delivery(irq)) {
> printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
> irq->delivery_mode = APIC_DM_FIXED;
> }
>
> - if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
> - return r;
> -
> memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
>
> kvm_for_each_vcpu(i, vcpu, kvm) {
>

Applied.

Paolo