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[Xen-devel] [PATCH] linux-2.6.18-xen.hg: fix interaction of NTP and dom0

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Subject: [Xen-devel] [PATCH] linux-2.6.18-xen.hg: fix interaction of NTP and dom0->xen time updates
From: Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Date: Wed, 18 Mar 2009 11:14:10 +0000
Delivery-date: Wed, 18 Mar 2009 04:14:47 -0700
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Don't discard NTP sync when updating Xen wallclock time from dom0,
as that's almost the first thing we do when we become synced.
Move the call to ntp_clear() into do_settimeofday(), which is the
only caller of __update_wallclock() that looks like it should break
NTP sync.  

This fixes the timer chain that sets Xen's wallclock every minute when
dom0 is NTP synced, which in turn greatly improves wallclock accuracy in
PV domU.

Signed-off-by: Tim Deegan <Tim.Deegan@xxxxxxxxxx>

Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Principal Software Engineer, Citrix Systems (R&D) Ltd.
[Company #02300071, SL9 0DZ, UK.]

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