path: root/arch/x86/lguest
diff options
authorDavid Vrabel <david.vrabel@citrix.com>2013-05-13 18:56:06 +0100
committerJohn Stultz <john.stultz@linaro.org>2013-05-28 14:00:59 -0700
commit3565184ed0c1ea46bea5b792da5f72a83c43e49b (patch)
tree4846a589a6aa295634ef585e5637872f15c19993 /arch/x86/lguest
parent0a0a7e66fa269de78975ea8d4e825a66d92b8d70 (diff)
x86: Increase precision of x86_platform.get/set_wallclock()
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@citrix.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
Diffstat (limited to 'arch/x86/lguest')
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 7114c63f047d..8424d5adcfa2 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -882,9 +882,9 @@ int lguest_setup_irq(unsigned int irq)
* It would be far better for everyone if the Guest had its own clock, but
* until then the Host gives us the time on every interrupt.
-static unsigned long lguest_get_wallclock(void)
+static void lguest_get_wallclock(struct timespec *now)
- return lguest_data.time.tv_sec;
+ *now = lguest_data.time;

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