From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v3 12/14] KVM: x86: add a flag to disable KVM x2apic
 broadcast quirk
Date: Wed, 13 Jul 2016 12:15:03 +0200
Message-ID: <10fcb396-853f-e08b-48d9-c2e69189798d@redhat.com>
References: <20160712200930.32143-1-rkrcmar@redhat.com>
 <20160712200930.32143-13-rkrcmar@redhat.com>
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Cc: "Lan, Tianyu" <tianyu.lan@intel.com>,
	Igor Mammedov <imammedo@redhat.com>,
	Jan Kiszka <jan.kiszka@web.de>, Peter Xu <peterx@redhat.com>,
	Yang Zhang <yang.zhang.wz@gmail.com>
To: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
	linux-kernel@vger.kernel.org, kvm@vger.kernel.org
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On 12/07/2016 22:09, Radim Kr=C4=8Dm=C3=A1=C5=99 wrote:
> +static bool kvm_apic_map_need_slowpath(struct kvm *kvm, struct kvm_l=
apic **src,
> +		struct kvm_lapic_irq *irq, struct kvm_apic_map *map)
> +{
> +	if (!map)
> +		return true;
> +
> +	if (kvm->arch.x2apic_broadcast_quirk_disabled) {
> +		if ((irq->dest_id =3D=3D APIC_BROADCAST &&
> +				map->mode !=3D KVM_APIC_MODE_X2APIC))
> +			return true;
> +		if (irq->dest_id =3D=3D X2APIC_BROADCAST)
> +			return true;
> +	} else {
> +		bool x2apic_ipi =3D src && *src && apic_x2apic_mode(*src);
> +		if (irq->dest_id =3D=3D (x2apic_ipi ?
> +		                     X2APIC_BROADCAST : APIC_BROADCAST))
> +			return true;
> +	}
> +
> +	return false;
> +}

This isn't the only case where you go through the slowpath.  What about
renaming to kvm_apic_dest_is_broadcast?

Paolo