Re: [PATCH 1/3] x86: increase precision of x86_platform.get/set_wallclock()

From: John Stultz
Date: Mon May 13 2013 - 20:57:36 EST


On 05/13/2013 10:56 AM, David Vrabel wrote:
From: David Vrabel <david.vrabel@xxxxxxxxxx>

All the virtualized platforms (KVM, lguest and Xen) have persistent
wallclocks that have more than one second of precision.

read_persistent_wallclock() and update_persistent_wallclock() allow
for nanosecond precision but their implementation on x86 with
x86_platform.get/set_wallclock() only allows for one second precision.
This means guests may see a wallclock time that is off by up to 1
second.

Make set_wallclock() and get_wallclock() take a struct timespec
parameter (which allows for nanosecond precision) so KVM and Xen
guests may start with a more accurate wallclock time and a Xen dom0
can maintain a more accurate wallclock for guests.

Signed-off-by: David Vrabel <david.vrabel@xxxxxxxxxx>

This one looks pretty good.
Lets circle around on the other two and if after that they still don't make sense, I'll just queue this one.

Sorry if I'm being thick headed.

thanks
-john

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