diff options
| author | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2010-05-14 12:48:19 +0100 |
|---|---|---|
| committer | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2010-07-26 23:13:25 -0700 |
| commit | 409771d258e9dd71c30f3c9520fd2b796ffc40f0 (patch) | |
| tree | 68678275563114e9d381ae587fc80bd4d34a7e90 /include/xen/interface/features.h | |
| parent | 99ad198c4978036bb9f7ebd11618b225b77046da (diff) | |
x86: Use xen_vcpuop_clockevent, xen_clocksource and xen wallclock.
Use xen_vcpuop_clockevent instead of hpet and APIC timers as main
clockevent device on all vcpus, use the xen wallclock time as wallclock
instead of rtc and use xen_clocksource as clocksource.
The pv clock algorithm needs to work correctly for the xen_clocksource
and xen wallclock to be usable, only modern Xen versions offer a
reliable pv clock in HVM guests (XENFEAT_hvm_safe_pvclock).
Using the hpet as clocksource means a VMEXIT every time we read/write to
the hpet mmio addresses, pvclock give us a better rating without
VMEXITs. Same goes for the xen wallclock and xen_vcpuop_clockevent
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Don Dutile <ddutile@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Diffstat (limited to 'include/xen/interface/features.h')
| -rw-r--r-- | include/xen/interface/features.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/xen/interface/features.h b/include/xen/interface/features.h index 8ab08b91bf6f..70d2563ab166 100644 --- a/include/xen/interface/features.h +++ b/include/xen/interface/features.h @@ -44,6 +44,9 @@ /* x86: Does this Xen host support the HVM callback vector type? */ #define XENFEAT_hvm_callback_vector 8 +/* x86: pvclock algorithm is safe to use on HVM */ +#define XENFEAT_hvm_safe_pvclock 9 + #define XENFEAT_NR_SUBMAPS 1 #endif /* __XEN_PUBLIC_FEATURES_H__ */ |