Re: [PATCH 2/2] KVM: lapic: don't recalculate apic map table twice when enabling LAPIC

From: Radim KrÄmÃÅ
Date: Wed Aug 03 2016 - 05:58:05 EST


2016-08-03 12:04+0800, Wanpeng Li:
> From: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
>
> APIC map table is recalculated during reset APIC ID to the initial value
> when enabling LAPIC. This patch move the recalculate_apic_map() to the
> next branch since we don't need to recalculate apic map twice in current
> codes.
>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
> Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
> ---

Reviewed-by: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>

> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> @@ -1760,9 +1760,10 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
> if (value & MSR_IA32_APICBASE_ENABLE) {
> kvm_apic_set_xapic_id(apic, vcpu->vcpu_id);
> static_key_slow_dec_deferred(&apic_hw_disabled);
> - } else
> + } else {
> static_key_slow_inc(&apic_hw_disabled.key);
> - recalculate_apic_map(vcpu->kvm);
> + recalculate_apic_map(vcpu->kvm);
> + }
> }
>
> if ((old_value ^ value) & X2APIC_ENABLE) {
> --
> 1.9.1
>