[PATCH 0/4] kvmclock: improve accuracy

From: Paolo Bonzini
Date: Mon Feb 08 2016 - 10:18:40 EST


Currently kvmclock is obtaining the multiplier and shift value from
the TSC kHz. These however are less accurate than the host kernel's
clock, which includes corrections made through NTP.

These patches change kvmclock to tick at the same frequency as the
host kernel's clocksource (as obtained through the pvclock_gtod
notifier). This is precise enough that the Hyper-V clock can be
implemented on top of it.

Paolo Bonzini (4):
KVM: x86: rename argument to kvm_set_tsc_khz
KVM: x86: rewrite handling of scaled TSC for kvmclock
KVM: x86: pass kvm_get_time_scale arguments in hertz
KVM: x86: track actual TSC frequency from the timekeeper struct

arch/x86/include/asm/kvm_host.h | 3 +-
arch/x86/kvm/x86.c | 73 +++++++++++++++++++++++++----------------
2 files changed, 47 insertions(+), 29 deletions(-)

--
1.8.3.1