From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: KVM PMU virtualization Date: Fri, 26 Feb 2010 15:33:21 +0200 Message-ID: <4B87CDA1.7070103@redhat.com> References: <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> <20100226123850.GA19476@elte.hu> <4B87C6C4.3040407@redhat.com> <4B87C8EC.8080304@redhat.com> <20100226132751.GA20013@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Jes Sorensen , Joerg Roedel , KVM General , Peter Zijlstra , Zachary Amsden , Gleb Natapov , ming.m.lin@intel.com, "Zhang, Yanmin" , Peter Zijlstra , Thomas Gleixner , "H. Peter Anvin" , Arjan van de Ven , Fr??d??ric Weisbecker , Arnaldo Carvalho de Melo To: Ingo Molnar Return-path: Received: from mx1.redhat.com ([209.132.183.28]:45702 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936110Ab0BZNd6 (ORCPT ); Fri, 26 Feb 2010 08:33:58 -0500 In-Reply-To: <20100226132751.GA20013@elte.hu> Sender: kvm-owner@vger.kernel.org List-ID: On 02/26/2010 03:27 PM, Ingo Molnar wrote: > > For Linux<->Linux the sanest, tier-1 approach would be to map sys_perf_open() > on the guest side over to the host, transparently, via a paravirt driver. > Let us for the purpose of this discussion assume that we are also interested in supporting Windows and older Linux. Paravirt optimizations can be added after we have the basic functionality, if they prove necessary. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.