From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rik van Riel Subject: Re: [PATCH 12/18] Add clock sync request to hardware enable Date: Wed, 14 Jul 2010 22:32:45 -0400 Message-ID: <4C3E734D.2020402@redhat.com> References: <1278987938-23873-1-git-send-email-zamsden@redhat.com> <1278987938-23873-13-git-send-email-zamsden@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: KVM , Avi Kivity , Marcelo Tosatti , Glauber Costa , Linux-kernel To: Zachary Amsden Return-path: Received: from mx1.redhat.com ([209.132.183.28]:56756 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758145Ab0GOCcs (ORCPT ); Wed, 14 Jul 2010 22:32:48 -0400 In-Reply-To: <1278987938-23873-13-git-send-email-zamsden@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 07/12/2010 10:25 PM, Zachary Amsden wrote: > If there are active VCPUs which are marked as belonging to > a particular hardware CPU, request a clock sync for them when > enabling hardware; the TSC could be desynchronized on a newly > arriving CPU, and we need to recompute guests system time > relative to boot after a suspend event. > > This covers both cases. > > Note that it is acceptable to take the spinlock, as either > no other tasks will be running and no locks held (BSP after > resume), or other tasks will be guaranteed to drop the lock > relatively quickly (AP on CPU_STARTING). Acked-by: Rik van Riel -- All rights reversed