From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: [PATCH RFC V5 00/11] Paravirtualized ticketlocks
Date: Fri, 14 Oct 2011 12:10:33 -0700
Message-ID: <4E988929.8040801@goop.org>
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> <4E98815F.6080105@zytor.com>
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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
To: "H. Peter Anvin" <hpa@zytor.com>
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On 10/14/2011 11:37 AM, H. Peter Anvin wrote:
> 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.

We probably don't want all those implementations (near) inline, so they
would end up being plain function calls anyway.

    J