[PATCH 2/2] kvm: x86: move MSR_IA32_TSC handling to x86.c

From: Paolo Bonzini
Date: Fri Apr 13 2018 - 07:23:49 EST


This is not specific to Intel/AMD anymore. The TSC offset is available
in vcpu->arch.tsc_offset.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/svm.c | 9 ---------
arch/x86/kvm/vmx.c | 20 --------------------
arch/x86/kvm/x86.c | 6 ++++++
3 files changed, 6 insertions(+), 29 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index ea7c6d29aca5..e636ef8cf3ce 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -4050,12 +4050,6 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
struct vcpu_svm *svm = to_svm(vcpu);

switch (msr_info->index) {
- case MSR_IA32_TSC: {
- msr_info->data = svm->vmcb->control.tsc_offset +
- kvm_scale_tsc(vcpu, rdtsc());
-
- break;
- }
case MSR_STAR:
msr_info->data = svm->vmcb->save.star;
break;
@@ -4208,9 +4202,6 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
svm->vmcb->save.g_pat = data;
mark_dirty(svm->vmcb, VMCB_NPT);
break;
- case MSR_IA32_TSC:
- kvm_write_tsc(vcpu, msr);
- break;
case MSR_IA32_SPEC_CTRL:
if (!msr->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_IBRS))
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 6553419202ee..e26c1f1c0a08 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2886,20 +2886,6 @@ static u64 vmx_read_l1_tsc_offset(struct kvm_vcpu *vcpu)
}

/*
- * reads and returns guest's timestamp counter "register"
- * guest_tsc = (host_tsc * tsc multiplier) >> 48 + tsc_offset
- * -- Intel TSC Scaling for Virtualization White Paper, sec 1.3
- */
-static u64 guest_read_tsc(struct kvm_vcpu *vcpu)
-{
- u64 host_tsc, tsc_offset;
-
- host_tsc = rdtsc();
- tsc_offset = vmcs_read64(TSC_OFFSET);
- return kvm_scale_tsc(vcpu, host_tsc) + tsc_offset;
-}
-
-/*
* writes 'offset' into guest's timestamp counter offset register
*/
static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
@@ -3529,9 +3515,6 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
#endif
case MSR_EFER:
return kvm_get_msr_common(vcpu, msr_info);
- case MSR_IA32_TSC:
- msr_info->data = guest_read_tsc(vcpu);
- break;
case MSR_IA32_SPEC_CTRL:
if (!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_IBRS) &&
@@ -3651,9 +3634,6 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return 1;
vmcs_write64(GUEST_BNDCFGS, data);
break;
- case MSR_IA32_TSC:
- kvm_write_tsc(vcpu, msr_info);
- break;
case MSR_IA32_SPEC_CTRL:
if (!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_IBRS) &&
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3f3fba58c960..51ecd381793b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2364,6 +2364,9 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return 1;
vcpu->arch.smbase = data;
break;
+ case MSR_IA32_TSC:
+ kvm_write_tsc(vcpu, msr_info);
+ break;
case MSR_SMI_COUNT:
if (!msr_info->host_initiated)
return 1;
@@ -2607,6 +2610,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
case MSR_IA32_UCODE_REV:
msr_info->data = vcpu->arch.microcode_version;
break;
+ case MSR_IA32_TSC:
+ msr_info->data = kvm_scale_tsc(vcpu, rdtsc()) + vcpu->arch.tsc_offset;
+ break;
case MSR_MTRRcap:
case 0x200 ... 0x2ff:
return kvm_mtrr_get_msr(vcpu, msr_info->index, &msr_info->data);
--
1.8.3.1