From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752843Ab2GONAR (ORCPT ); Sun, 15 Jul 2012 09:00:17 -0400 Received: from mail-qa0-f46.google.com ([209.85.216.46]:46952 "EHLO mail-qa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752708Ab2GONAK (ORCPT ); Sun, 15 Jul 2012 09:00:10 -0400 Message-ID: <5002BEE3.5060506@gmail.com> Date: Sun, 15 Jul 2012 07:00:19 -0600 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Avi Kivity , Gleb Natapov CC: Peter Zijlstra , LKML Subject: Re: perf with precise attribute kills all KVM based VMs References: <1341845396.3462.81.camel@twins> <4FFAEFF1.9000706@redhat.com> <1341845999.3462.86.camel@twins> <4FFCBD00.1030109@gmail.com> <20120711071006.GF23898@redhat.com> <1342000187.3462.134.camel@twins> <20120711095337.GJ23898@redhat.com> <4FFE4E8D.90606@gmail.com> <20120712042923.GG7298@redhat.com> <4FFEEB55.5070009@gmail.com> <20120712160634.GI7298@redhat.com> <50027A36.9070509@redhat.com> In-Reply-To: <50027A36.9070509@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/15/12 2:07 AM, Avi Kivity wrote: > On 07/12/2012 07:06 PM, Gleb Natapov wrote: >>> >>> Note the :pH this time. >> I am not sure what perf kvm does with :pH modifier, but H modifier does >> not make sense with perf kvm and should be reported as an error by perf tool. > > Maybe it should refer to the guest vs. the nested guest... :H = host mode; you are thinking of :h for hypervisor mode. From perf-list documentation: "Modifiers allow the user to restrict when events are counted with 'u' for user-space, 'k' for kernel, 'h' for hypervisor. Additional modifiers are 'G' for guest counting (in KVM guests) and 'H' for host counting (not in KVM guests)." > > Well that's a horrible UI but we do need some way to distinguish among > the two. Samples from the nested guest's kernel will make no sense when > looking at the guest kernel. I guess we should default to exclude > nested guest mode. > I catch a return flight in a couple of hours. I will send a summary email tonight to make sure we are on the same page with the problem, uses cases and patches. David