Re: [PATCH v2 05/15] kvm: lapic: Introduce APICv update helper function

From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: "Suthikulpanit\, Suravee" <Suravee.Suthikulpanit@amd.com>
Cc: "pbonzini\@redhat.com" <pbonzini@redhat.com>,
	"rkrcmar\@redhat.com" <rkrcmar@redhat.com>,
	"joro\@8bytes.org" <joro@8bytes.org>,
	"graf\@amazon.com" <graf@amazon.com>,
	"jschoenh\@amazon.de" <jschoenh@amazon.de>,
	"karahmed\@amazon.de" <karahmed@amazon.de>,
	"rimasluk\@amazon.com" <rimasluk@amazon.com>, "Grimm\,
	Jon" <Jon.Grimm@amd.com>, "Suthikulpanit\,
	Suravee" <Suravee.Suthikulpanit@amd.com>,
	"linux-kernel\@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"kvm\@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: [PATCH v2 05/15] kvm: lapic: Introduce APICv update helper function
Date: Tue, 27 Aug 2019 09:22:50 +0200	[thread overview]
Message-ID: <87a7bvm5rp.fsf@vitty.brq.redhat.com> (raw)
In-Reply-To: <1565886293-115836-6-git-send-email-suravee.suthikulpanit@amd.com>

"Suthikulpanit, Suravee" <Suravee.Suthikulpanit@amd.com> writes:

> Re-factor code into a helper function for setting lapic parameters when
> activate/deactivate APICv, and export the function for subsequent usage.
>
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
> ---
>  arch/x86/kvm/lapic.c | 22 +++++++++++++++++-----
>  arch/x86/kvm/lapic.h |  1 +
>  2 files changed, 18 insertions(+), 5 deletions(-)
>
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 4dabc31..90f79ca 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -2153,6 +2153,21 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
>  
>  }
>  
> +void kvm_apic_update_apicv(struct kvm_vcpu *vcpu)
> +{
> +	struct kvm_lapic *apic = vcpu->arch.apic;
> +
> +	if (vcpu->arch.apicv_active) {
> +		/* irr_pending is always true when apicv is activated. */
> +		apic->irr_pending = true;
> +		apic->isr_count = 1;
> +	} else {
> +		apic->irr_pending = (apic_search_irr(apic) != -1);
> +		apic->isr_count = count_vectors(apic->regs + APIC_ISR);
> +	}
> +}
> +EXPORT_SYMBOL(kvm_apic_update_apicv);

EXPORT_SYMBOL_GPL please.

> +
>  void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
>  {
>  	struct kvm_lapic *apic = vcpu->arch.apic;
> @@ -2197,8 +2212,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
>  		kvm_lapic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
>  		kvm_lapic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
>  	}
> -	apic->irr_pending = vcpu->arch.apicv_active;
> -	apic->isr_count = vcpu->arch.apicv_active ? 1 : 0;
> +	kvm_apic_update_apicv(vcpu);
>  	apic->highest_isr_cache = -1;
>  	update_divide_count(apic);
>  	atomic_set(&apic->lapic_timer.pending, 0);
> @@ -2468,9 +2482,7 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
>  	apic_manage_nmi_watchdog(apic, kvm_lapic_get_reg(apic, APIC_LVT0));
>  	update_divide_count(apic);
>  	start_apic_timer(apic);
> -	apic->irr_pending = true;
> -	apic->isr_count = vcpu->arch.apicv_active ?
> -				1 : count_vectors(apic->regs + APIC_ISR);
> +	kvm_apic_update_apicv(vcpu);
>  	apic->highest_isr_cache = -1;
>  	if (vcpu->arch.apicv_active) {
>  		kvm_x86_ops->apicv_post_state_restore(vcpu);
> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
> index d6d049b..3892d50 100644
> --- a/arch/x86/kvm/lapic.h
> +++ b/arch/x86/kvm/lapic.h
> @@ -90,6 +90,7 @@ bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
>  int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
>  		     struct dest_map *dest_map);
>  int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type);
> +void kvm_apic_update_apicv(struct kvm_vcpu *vcpu);
>  
>  bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
>  		struct kvm_lapic_irq *irq, int *r, struct dest_map *dest_map);

-- 
Vitaly