KVM: x86: Replace call-back compute_tsc_offset() with a common function

[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c314e8d22a671f80e8f2323137478eb507101d00..bb46066e125b95ad65e226a673631624b8de0b4f 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1392,6 +1392,15 @@ u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc)
 }
 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 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr)
        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 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr)
                } 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 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
                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;