This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] how to keep time of windows pvhvm synchronized with host

To: Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Subject: Re: [Xen-devel] how to keep time of windows pvhvm synchronized with host after resuming
From: ANNIE LI <annie.li@xxxxxxxxxx>
Date: Sat, 25 Sep 2010 10:26:14 +0800
Cc: Paul Durrant <Paul.Durrant@xxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Fri, 24 Sep 2010 19:29:08 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20100924151826.GC24250@xxxxxxxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Organization: Oracle Corporation
References: <4C91D5C0.5030802@xxxxxxxxxx> <291EDFCB1E9E224A99088639C47620228CF769FEC1@xxxxxxxxxxxxxxxxxxxxxxxxx> <20100916091914.GC11387@xxxxxxxxxxxxxxxxxxxxxxx> <4C9346AA.4040902@xxxxxxxxxx> <20100917114304.GE11387@xxxxxxxxxxxxxxxxxxxxxxx> <4C99C385.3040602@xxxxxxxxxx> <20100923081912.GC22692@xxxxxxxxxxxxxxxxxxxxxxx> <4C9CAD6D.3030803@xxxxxxxxxx> <20100924151826.GC24250@xxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20100915 Thunderbird/3.1.4

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.


Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>