From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755880Ab1KGRRX (ORCPT ); Mon, 7 Nov 2011 12:17:23 -0500 Received: from mx1.redhat.com ([209.132.183.28]:1599 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754814Ab1KGRRW (ORCPT ); Mon, 7 Nov 2011 12:17:22 -0500 Date: Mon, 7 Nov 2011 19:17:02 +0200 From: Gleb Natapov To: Peter Zijlstra Cc: kvm@vger.kernel.org, avi@redhat.com, mtosatti@redhat.com, linux-kernel@vger.kernel.org, mingo@elte.hu, acme@ghostprotocols.net Subject: Re: [PATCHv2 2/9] KVM: Expose a version 2 architectural PMU to a guests Message-ID: <20111107171702.GA11367@redhat.com> References: <1320323618-10375-1-git-send-email-gleb@redhat.com> <1320323618-10375-3-git-send-email-gleb@redhat.com> <1320676609.18053.44.camel@twins> <20111107152540.GF8670@redhat.com> <1320684314.17809.29.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1320684314.17809.29.camel@twins> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 07, 2011 at 05:45:14PM +0100, Peter Zijlstra wrote: > On Mon, 2011-11-07 at 17:25 +0200, Gleb Natapov wrote: > > > Since the below programming doesn't use perf_event_attr::pinned, yes. > > > > > Yes, that is on todo :). Actually I do want to place all guest perf > > counters into the same event group and make it pinned. But currently perf > > event groups are not very flexible. In our usage scenario we can't have > > one event as a group leader since events are created and destroyed very > > dynamically. What I would like is to have something like meta event that > > will group all other real event. > > Is there a reason to have them grouped if you pin them all anyway? Hmm good question. May be we shouldn't pin then since this will prevent profiling vcpu task on a host while perf is running in a guest, but then we need to group guest created event to get meaningful result. I think I'll pin them for now and will look into grouping them later. -- Gleb.