From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: KVM PMU virtualization
Date: Fri, 26 Feb 2010 16:55:48 +0100
Message-ID: <1267199748.22519.725.camel@laptop>
References: <4B86917C.4070102@redhat.com> <20100225173423.GB4246@8bytes.org>
	 <20100226084241.GF15885@elte.hu> <4B87987A.2020302@redhat.com>
	 <20100226104437.GB7463@elte.hu> <4B87AF44.9090702@redhat.com>
	 <20100226114217.GI7463@elte.hu> <4B87B5DE.30503@redhat.com>
	 <20100226120750.GA11578@elte.hu> <4B87BC74.7050207@redhat.com>
	 <20100226133149.GA23422@elte.hu> <4B87CE93.1070906@redhat.com>
	 <4B87D2EA.1090503@redhat.com> <1267194420.22519.605.camel@laptop>
	 <4B87E09C.3080209@redhat.com> <1267196885.22519.643.camel@laptop>
	 <4B87E4B6.2070009@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Cc: Jes Sorensen <Jes.Sorensen@redhat.com>,
	Ingo Molnar <mingo@elte.hu>, Joerg Roedel <joro@8bytes.org>,
	KVM General <kvm@vger.kernel.org>,
	Zachary Amsden <zamsden@redhat.com>,
	Gleb Natapov <gleb@redhat.com>, ming.m.lin@intel.com,
	"Zhang, Yanmin" <yanmin_zhang@linux.intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Arjan van de Ven <arjan@infradead.org>,
	Fr??d??ric Weisbecker <fweisbec@gmail.com>,
	Arnaldo Carvalho de Melo <acme@redhat.com>
To: Avi Kivity <avi@redhat.com>
Return-path: <kvm-owner@vger.kernel.org>
Received: from bombadil.infradead.org ([18.85.46.34]:39308 "EHLO
	bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S965189Ab0BZP4B (ORCPT <rfc822;kvm@vger.kernel.org>);
	Fri, 26 Feb 2010 10:56:01 -0500
In-Reply-To: <4B87E4B6.2070009@redhat.com>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

On Fri, 2010-02-26 at 17:11 +0200, Avi Kivity wrote:
> On 02/26/2010 05:08 PM, Peter Zijlstra wrote:
> >> That's 7 more than what we support now, and 7 more than what we can
> >> guarantee without it.
> >>      
> > Again, what windows software uses only those 7? Does it pay to only have
> > access to those 7 or does it limit the usability to exactly the same
> > subset a paravirt interface would?
> >    
> 
> Good question.  Would be interesting to try out VTune with the non-arch 
> pmu masked out.

Also, the ANY bit is part of the intel arch pmu, but you still have to
mask it out.

BTW, just wondering, why would a developer be running VTune in a guest
anyway? I'd think that a developer that windows oriented would simply
run windows on his desktop and VTune there.