From mboxrd@z Thu Jan 1 00:00:00 1970 From: ANNIE LI Subject: Re: how to keep time of windows pvhvm synchronized with host after resuming Date: Sat, 25 Sep 2010 10:26:14 +0800 Message-ID: <4C9D5DC6.3040209@oracle.com> References: <4C91D5C0.5030802@oracle.com> <291EDFCB1E9E224A99088639C47620228CF769FEC1@LONPMAILBOX01.citrite.net> <20100916091914.GC11387@whitby.uk.xensource.com> <4C9346AA.4040902@oracle.com> <20100917114304.GE11387@whitby.uk.xensource.com> <4C99C385.3040602@oracle.com> <20100923081912.GC22692@whitby.uk.xensource.com> <4C9CAD6D.3030803@oracle.com> <20100924151826.GC24250@whitby.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100924151826.GC24250@whitby.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Tim Deegan Cc: Paul Durrant , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 2010-9-24 23:18, Tim Deegan wrote: > > No, that's fine. wc_secs is what you add to NOW() to get wallclock to > it shouldn't change, or at least very rarely. I thought from your > earlier email that it was always zero, which would be odd. Thanks for your confirmation. I thought wc_secs is a changeable value, so i am wrong. The NOW() is calling get_s_time() here, which has problem with RDTSC you mentioned. So the next step is to get system time through hypercall HVMOP_get_time, and then add wc_secs to get wallclock. Is it the patch you mentioned in http://lists.xensource.com/archives/html/xen-devel/2010-07/msg00477.html ? I will add this patch and get the wallclock time then. > > And is that equal to zero? If not, what exactly is the problem? I > think I've got confused about what's going wrong. Yes, I got zero value for wc_secs several days ago. But it became non-zero after i rebooted dom0, and i failed to reproduce the issue now. I assumed wc_secs should change regularly. Sorry for my misunderstanding. Thanks Annie