From: Haozhong Zhang <haozhong.zhang@intel.com>
Date: Tue, 19 Jan 2016 15:07:39 +0000 (+0100)
Subject: x86/time: scale host TSC in pvclock properly
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~1925
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=eab8a90be723d742d607aff2005ea0ab521bfd6a;p=xen.git

x86/time: scale host TSC in pvclock properly

This patch makes the pvclock return the scaled host TSC and
corresponding scaling parameters to HVM domains if guest TSC is not
emulated and TSC scaling is enabled.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---

diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index ec3f33e686..988403aedf 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -815,10 +815,18 @@ static void __update_vcpu_system_time(struct vcpu *v, int force)
     }
     else
     {
-        tsc_stamp = t->local_tsc_stamp;
-
-        _u.tsc_to_system_mul = t->tsc_scale.mul_frac;
-        _u.tsc_shift         = (s8)t->tsc_scale.shift;
+        if ( has_hvm_container_domain(d) && cpu_has_tsc_ratio )
+        {
+            tsc_stamp            = hvm_funcs.scale_tsc(v, t->local_tsc_stamp);
+            _u.tsc_to_system_mul = d->arch.vtsc_to_ns.mul_frac;
+            _u.tsc_shift         = d->arch.vtsc_to_ns.shift;
+        }
+        else
+        {
+            tsc_stamp            = t->local_tsc_stamp;
+            _u.tsc_to_system_mul = t->tsc_scale.mul_frac;
+            _u.tsc_shift         = t->tsc_scale.shift;
+        }
     }
 
     _u.tsc_timestamp = tsc_stamp;