From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: in-kernel interrupt controller steering
Date: Wed, 6 Mar 2013 15:16:14 +0200
Message-ID: <20130306131614.GS11223@redhat.com>
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 <20563F35-046C-432C-9F7A-0CEF38180964@suse.de>
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Cc: Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
	kvm-ppc@vger.kernel.org, Stuart Yoder <stuart.yoder@freescale.com>,
	Scott Wood <scottwood@freescale.com>,
	Paul Mackerras <paulus@samba.org>,
	Peter Maydell <peter.maydell@linaro.org>
To: Alexander Graf <agraf@suse.de>
Return-path: <kvm-ppc-owner@vger.kernel.org>
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On Wed, Mar 06, 2013 at 12:58:39PM +0100, Alexander Graf wrote:
> 
> On 06.03.2013, at 12:57, Paolo Bonzini wrote:
> 
> >>> I agree.  But is the device really being created at CREATE_DEVICE
> >>> time? What happens if you create N CPUs and N-1 irqchips?
> >> 
> >> irqchip in CREATE_DEVICE is the IOAPIC, not the LAPIC. The LAPIC gets
> >> spawned at vcpu creation.
> >> 
> >>> On x86, the LAPIC is created magically together with the VCPU.
> >> 
> >> Yes, and so far I haven't seen any proposal to change this even in
> >> the CREATE_DEVICE world.
> > 
> > But don't you need anyway an id to get/set the device properties of
> > the per-VCPU irqchip?  If you were adding the x86 irqchip with the
> > new API, what would be the replacement of KVM_GET_LAPIC/KVM_SET_LAPIC?
> 
> In the current model, that would be ONE_REG registers on the vcpus.
> 
Yes, the same way as KVM_GET_LAPIC is per cpu ioctl. No need for special
ID.

--
			Gleb.