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Date: Thu, 18 Nov 2010 15:14:53 +0200
From: Gleb Natapov <gleb@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Avi Kivity <avi@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>,
        Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>,
        Gregory Haskins <ghaskins@novell.com>,
        Chris Lalancette <clalance@redhat.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC] kvm: fast-path msi injection with irqfd
Message-ID: <20101118131453.GO7948@redhat.com>
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 <20101118130337.GA2254@redhat.com>
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On Thu, Nov 18, 2010 at 03:03:37PM +0200, Michael S. Tsirkin wrote:
> > >+static inline void kvm_irq_routing_update(struct kvm *kvm,
> > >+					  struct kvm_irq_routing_table *irq_rt)
> > >+{
> > >+	rcu_assign_pointer(kvm->irq_routing, irq_rt);
> > >+}
> > >+
> > >  static inline int kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
> > >  {
> > >  	return -ENOSYS;
> > 
> > Apart from these minor issues, looks good.
> 
> 
> Something we should consider improving is the loop over all VCPUs that
> kvm_irq_delivery_to_apic invokes.  I think that (for non-broadcast
> interrupts) it should be possible to precompute an store the CPU
> in question as part of the routing entry.
> 
> Something for a separate patch ... comments?
> 
I do not think this info should be part of routing entry. Routing entry
is more about describing wires on the board. Other then that
this is a good idea that, IIRC, we already discussed once.

--
			Gleb.