[PATCH 16/18] Use getnsboottime in KVM

Zachary Amsden
2010-07-13T02:26:19Z

Signed-off-by: Zachary Amsden <zamsden@redhat.com>
---
arch/x86/kvm/x86.c | 22 ++++++----------------
1 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f9994c3..e73ddf6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -891,16 +891,6 @@ static void kvm_set_time_scale(uint32_t tsc_khz, struct pvclock_vcpu_time_info *
hv_clock->tsc_to_system_mul);
}

-static inline u64 get_kernel_ns(void)
-{
- struct timespec ts;
-
- WARN_ON(preemptible());
- ktime_get_ts(&ts);
- monotonic_to_bootbased(&ts);
- return timespec_to_ns(&ts);
-}
-
static DEFINE_PER_CPU(unsigned long, cpu_tsc_khz);

static inline int kvm_tsc_changes_freq(void)
@@ -930,7 +920,7 @@ void guest_write_tsc(struct kvm_vcpu *vcpu, u64 data)

spin_lock(&kvm->arch.tsc_write_lock);
offset = data - native_read_tsc();
- ns = get_kernel_ns();
+ ns = getnsboottime();
elapsed = ns - kvm->arch.last_tsc_nsec;
sdiff = data - kvm->arch.last_tsc_write;
if (sdiff < 0)
@@ -983,7 +973,7 @@ static int kvm_write_guest_time(struct kvm_vcpu *v)
/* Keep irq disabled to prevent changes to the clock */
local_irq_save(flags);
kvm_get_msr(v, MSR_IA32_TSC, &tsc_timestamp);
- kernel_ns = get_kernel_ns();
+ kernel_ns = getnsboottime();
this_tsc_khz = __get_cpu_var(cpu_tsc_khz);
local_irq_restore(flags);

@@ -1928,7 +1918,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
if (check_tsc_unstable()) {
/* Subtract elapsed cycle time */
u64 ns = !vcpu->arch.last_host_ns ? 0 :
- get_kernel_ns() - vcpu->arch.last_host_ns;
+ getnsboottime() - vcpu->arch.last_host_ns;
tsc_delta -= nsec_to_cycles(ns);
kvm_x86_ops->adjust_tsc_offset(vcpu, -tsc_delta);
}
@@ -1943,7 +1933,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
kvm_x86_ops->vcpu_put(vcpu);
kvm_put_guest_fpu(vcpu);
vcpu->arch.last_host_tsc = native_read_tsc();
- vcpu->arch.last_host_ns = get_kernel_ns();
+ vcpu->arch.last_host_ns = getnsboottime();
}

static int is_efer_nx(void)
@@ -3336,7 +3326,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
goto out;

r = 0;
- now_ns = get_kernel_ns();
+ now_ns = getnsboottime();
delta = user_ns.clock - now_ns;
kvm->arch.kvmclock_offset = delta;
break;
@@ -3345,7 +3335,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
struct kvm_clock_data user_ns;
u64 now_ns;

- now_ns = get_kernel_ns();
+ now_ns = getnsboottime();
user_ns.clock = kvm->arch.kvmclock_offset + now_ns;
user_ns.flags = 0;

--
1.7.1