xen: drop xen_sched_clock in favour of using plain wallclock time
xen_sched_clock only counts unstolen time. In principle this should
be useful to the Linux scheduler so that it knows how much time a process
actually consumed. But in practice this doesn't work very well as the
scheduler expects the sched_clock time to be synchronized between
cpus. It also uses sched_clock to measure the time a task spends
sleeping, in which case "unstolen time" isn't meaningful.
So just use plain xen_clocksource_read to return wallclock nanoseconds
for sched_clock.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 399bed2..fef034a 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -926,7 +926,7 @@
};
static const struct pv_time_ops xen_time_ops __initdata = {
- .sched_clock = xen_sched_clock,
+ .sched_clock = xen_clocksource_read,
};
static const struct pv_cpu_ops xen_cpu_ops __initdata = {