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Date: Fri, 14 Oct 2011 11:37:19 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Jeremy Fitzhardinge <jeremy@goop.org>
CC: Jason Baron <jbaron@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ingo Molnar <mingo@elte.hu>, the arch/x86 maintainers <x86@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Nick Piggin <npiggin@kernel.dk>, Avi Kivity <avi@redhat.com>,
        Marcelo Tosatti <mtosatti@redhat.com>, KVM <kvm@vger.kernel.org>,
        Andi Kleen <andi@firstfloor.org>,
        Xen Devel <xen-devel@lists.xensource.com>,
        Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>,
        konrad.wilk@oracle.com
Subject: Re: [PATCH RFC V5 00/11] Paravirtualized ticketlocks
References: <cover.1318466916.git.jeremy.fitzhardinge@citrix.com> <1318503245.24856.12.camel@twins> <4E971580.6030300@goop.org> <20111014141701.GA2433@redhat.com> <4E986B2B.60803@goop.org>
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On 10/14/2011 10:02 AM, Jeremy Fitzhardinge wrote:
> 
> Jump labels are essentially binary: you can use path A or path B.  pvops
> are multiway: there's no limit to the number of potential number of
> paravirtualized hypervisor implementations.  At the moment we have 4:
> native, Xen, KVM and lguest.
> 

This isn't (or shouldn't be) really true... it should be possible to do
an N-way jump label even if the current mechanism doesn't.

	-hpa