get_kvmclock_base_ns
kvm->arch.kvmclock_offset = -get_kvmclock_base_ns();
ns = get_kvmclock_base_ns();
data->clock = get_kvmclock_base_ns() + ka->kvmclock_offset;
kernel_ns = get_kvmclock_base_ns();
ns = get_kvmclock_base_ns();
now_raw_ns = get_kvmclock_base_ns();