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From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [RFC PATCH 0/2] irq destination caching prototype
Date: Mon, 13 Aug 2012 14:19:32 +0300
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Cc: Gleb Natapov <gleb@redhat.com>, kvm@vger.kernel.org,
	Jan Kiszka <jan.kiszka@web.de>
To: Avi Kivity <avi@redhat.com>
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On Mon, Aug 13, 2012 at 02:03:51PM +0300, Avi Kivity wrote:
> On 08/13/2012 02:01 PM, Gleb Natapov wrote:
> >> 
> >> Actually this is overkill.  Suppose we do an apicid->vcpu translation
> >> cache?  Then we retain O(1) behaviour, no need for a huge cache.
> >> 
> > Not sure I follow.
> 
> Unicast MSIs and IPIs can be speeded up by looking up the vcpu using the
> apic id, using a static lookup table (only changed when the guest
> updates apicid or a vcpu is inserted).

Looks like kvm_apic_id is always 8 bit, so it's just a
table with 256 entries?


> 
> 
> -- 
> error compiling committee.c: too many arguments to function