From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752814Ab1AYB1J (ORCPT ); Mon, 24 Jan 2011 20:27:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:27830 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751521Ab1AYB1G (ORCPT ); Mon, 24 Jan 2011 20:27:06 -0500 Message-ID: <4D3E26E3.3000209@redhat.com> Date: Mon, 24 Jan 2011 20:26:59 -0500 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc13 Lightning/1.0b3pre Thunderbird/3.1.7 MIME-Version: 1.0 To: Glauber Costa CC: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, aliguori@us.ibm.com, Jeremy Fitzhardinge , Peter Zijlstra , Avi Kivity Subject: Re: [PATCH 14/16] KVM-GST: KVM Steal time registration References: <1295892397-11354-1-git-send-email-glommer@redhat.com> <1295892397-11354-15-git-send-email-glommer@redhat.com> <4D3E0BB9.5070805@redhat.com> <1295918712.15920.16.camel@mothafucka.localdomain> In-Reply-To: <1295918712.15920.16.camel@mothafucka.localdomain> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/24/2011 08:25 PM, Glauber Costa wrote: > On Mon, 2011-01-24 at 18:31 -0500, Rik van Riel wrote: >> On 01/24/2011 01:06 PM, Glauber Costa wrote: >>> Register steal time within KVM. Everytime we sample the steal time >>> information, we update a local variable that tells what was the >>> last time read. We then account the difference. >>> >>> Signed-off-by: Glauber Costa >>> CC: Rik van Riel >>> CC: Jeremy Fitzhardinge >>> CC: Peter Zijlstra >>> CC: Avi Kivity >> >> On second thought - how does this deal with cpu hotplug and >> hot unplug? >> >> Do you allocate a new one of these structs every time a cpu >> is hot unplugged and then hotplugged, leaking the old one? >> >> Will leaving the old value around confuse the steal time >> calculation? > > If you look closely, there are no allocations happening at all, > it's all static. In that case, does the per-cpu steal area need to be reinitialized at hotplug time? -- All rights reversed