From 409771d258e9dd71c30f3c9520fd2b796ffc40f0 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Fri, 14 May 2010 12:48:19 +0100 Subject: 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 Signed-off-by: Don Dutile Signed-off-by: Jeremy Fitzhardinge --- include/xen/interface/features.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/xen') diff --git a/include/xen/interface/features.h b/include/xen/interface/features.h index 8ab08b91bf6..70d2563ab16 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__ */ -- cgit v1.2.3-70-g09d2