kvm: x86: drop read_tsc_offset()

The TSC offset can now be read directly from struct kvm_arch_vcpu.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -954,7 +954,6 @@ struct kvm_x86_ops {
 
 	bool (*has_wbinvd_exit)(void);
 
-	u64 (*read_tsc_offset)(struct kvm_vcpu *vcpu);
 	void (*write_tsc_offset)(struct kvm_vcpu *vcpu, u64 offset);
 
 	u64 (*read_l1_tsc)(struct kvm_vcpu *vcpu, u64 host_tsc);

arch/x86/kvm/svm.c

@@ -1119,13 +1119,6 @@ static void init_sys_seg(struct vmcb_seg *seg, uint32_t type)
 	seg->base = 0;
 }
 
-static u64 svm_read_tsc_offset(struct kvm_vcpu *vcpu)
-{
-	struct vcpu_svm *svm = to_svm(vcpu);
-
-	return svm->vmcb->control.tsc_offset;
-}
-
 static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -5427,7 +5420,6 @@ static struct kvm_x86_ops svm_x86_ops = {
 
 	.has_wbinvd_exit = svm_has_wbinvd_exit,
 
-	.read_tsc_offset = svm_read_tsc_offset,
 	.write_tsc_offset = svm_write_tsc_offset,
 	.adjust_tsc_offset_guest = svm_adjust_tsc_offset_guest,
 	.read_l1_tsc = svm_read_l1_tsc,

arch/x86/kvm/vmx.c

@@ -2609,11 +2609,6 @@ static u64 vmx_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc)
 	return host_tsc + tsc_offset;
 }
 
-static u64 vmx_read_tsc_offset(struct kvm_vcpu *vcpu)
-{
-	return vmcs_read64(TSC_OFFSET);
-}
-
 /*
  * writes 'offset' into guest's timestamp counter offset register
  */
@@ -11286,7 +11281,6 @@ static struct kvm_x86_ops vmx_x86_ops = {
 
 	.has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
 
-	.read_tsc_offset = vmx_read_tsc_offset,
 	.write_tsc_offset = vmx_write_tsc_offset,
 	.adjust_tsc_offset_guest = vmx_adjust_tsc_offset_guest,
 	.read_l1_tsc = vmx_read_l1_tsc,

arch/x86/kvm/x86.c

@@ -1367,7 +1367,7 @@ static void kvm_track_tsc_matching(struct kvm_vcpu *vcpu)
 
 static void update_ia32_tsc_adjust_msr(struct kvm_vcpu *vcpu, s64 offset)
 {
-	u64 curr_offset = kvm_x86_ops->read_tsc_offset(vcpu);
+	u64 curr_offset = vcpu->arch.tsc_offset;
 	vcpu->arch.ia32_tsc_adjust_msr += offset - curr_offset;
 }