KVM: x86: Replace call-back compute_tsc_offset() with a common function
Both VMX and SVM calculate the tsc-offset in the same way, so this
patch removes the call-back compute_tsc_offset() and replaces it with a
common function kvm_compute_tsc_offset().
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c314e8d..bb46066 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1392,6 +1392,15 @@
}
EXPORT_SYMBOL_GPL(kvm_scale_tsc);
+static u64 kvm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
+{
+ u64 tsc;
+
+ tsc = kvm_scale_tsc(vcpu, rdtsc());
+
+ return target_tsc - tsc;
+}
+
void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr)
{
struct kvm *kvm = vcpu->kvm;
@@ -1403,7 +1412,7 @@
u64 data = msr->data;
raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
- offset = kvm_x86_ops->compute_tsc_offset(vcpu, data);
+ offset = kvm_compute_tsc_offset(vcpu, data);
ns = get_kernel_ns();
elapsed = ns - kvm->arch.last_tsc_nsec;
@@ -1460,7 +1469,7 @@
} else {
u64 delta = nsec_to_cycles(vcpu, elapsed);
data += delta;
- offset = kvm_x86_ops->compute_tsc_offset(vcpu, data);
+ offset = kvm_compute_tsc_offset(vcpu, data);
pr_debug("kvm: adjusted tsc offset by %llu\n", delta);
}
matched = true;
@@ -2687,7 +2696,7 @@
if (tsc_delta < 0)
mark_tsc_unstable("KVM discovered backwards TSC");
if (check_tsc_unstable()) {
- u64 offset = kvm_x86_ops->compute_tsc_offset(vcpu,
+ u64 offset = kvm_compute_tsc_offset(vcpu,
vcpu->arch.last_guest_tsc);
kvm_x86_ops->write_tsc_offset(vcpu, offset);
vcpu->arch.tsc_catchup = 1;