x86: paravirt: factor out cpu_khz to common code

KVM intends to use paravirt code to calibrate khz. Xen
current code will do just fine. So as a first step, factor out
code to pvclock.c.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 2 insertions, 9 deletions

diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 004ba86326ae..c9f7cda48ed7 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -198,17 +198,10 @@ unsigned long long xen_sched_clock(void)
 /* Get the TSC speed from Xen */
 unsigned long xen_tsc_khz(void)
 {
-        u64 xen_khz = 1000000ULL << 32;
-        const struct pvclock_vcpu_time_info *info =
+        struct pvclock_vcpu_time_info *info =
                 &HYPERVISOR_shared_info->vcpu_info[0].time;
 
-        do_div(xen_khz, info->tsc_to_system_mul);
-        if (info->tsc_shift < 0)
-                xen_khz <<= -info->tsc_shift;
-        else
-                xen_khz >>= info->tsc_shift;
-
-        return xen_khz;
+        return pvclock_tsc_khz(info);
 }
 
 cycle_t xen_clocksource_read(void)