[PATCH] KVM: stats: x86: vmx: add exit reason stats to vt-x instructions

[Jing Zhang <jingzhangos@google.com>]

These stats will be used to monitor the nested virtualization use in
VMs. Most importantly: VMXON exits are evidence that the guest has
enabled VMX, VMLAUNCH/VMRESUME exits are evidence that the guest has run
an L2.

Original-by: David Matlack <dmatlack@google.com>
Signed-off-by: Jing Zhang <jingzhangos@google.com>
---
 arch/x86/include/asm/kvm_host.h | 11 +++++++++++
 arch/x86/kvm/vmx/nested.c       | 17 +++++++++++++++++
 arch/x86/kvm/x86.c              | 13 ++++++++++++-
 3 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 09b256db394a..e3afbc7926e0 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1257,6 +1257,17 @@ struct kvm_vcpu_stat {
 	u64 directed_yield_attempted;
 	u64 directed_yield_successful;
 	u64 guest_mode;
+	u64 vmclear_exits;
+	u64 vmlaunch_exits;
+	u64 vmptrld_exits;
+	u64 vmptrst_exits;
+	u64 vmread_exits;
+	u64 vmresume_exits;
+	u64 vmwrite_exits;
+	u64 vmoff_exits;
+	u64 vmon_exits;
+	u64 invept_exits;
+	u64 invvpid_exits;
 };
 
 struct x86_instruction_info;
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index bc6327950657..8696f2612953 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -4879,6 +4879,7 @@ static int handle_vmon(struct kvm_vcpu *vcpu)
 	const u64 VMXON_NEEDED_FEATURES = FEAT_CTL_LOCKED
 		| FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX;
 
+	++vcpu->stat.vmon_exits;
 	/*
 	 * The Intel VMX Instruction Reference lists a bunch of bits that are
 	 * prerequisite to running VMXON, most notably cr4.VMXE must be set to
@@ -4964,6 +4965,7 @@ static inline void nested_release_vmcs12(struct kvm_vcpu *vcpu)
 /* Emulate the VMXOFF instruction */
 static int handle_vmoff(struct kvm_vcpu *vcpu)
 {
+	++vcpu->stat.vmoff_exits;
 	if (!nested_vmx_check_permission(vcpu))
 		return 1;
 
@@ -4984,6 +4986,7 @@ static int handle_vmclear(struct kvm_vcpu *vcpu)
 	u64 evmcs_gpa;
 	int r;
 
+	++vcpu->stat.vmclear_exits;
 	if (!nested_vmx_check_permission(vcpu))
 		return 1;
 
@@ -5025,6 +5028,7 @@ static int handle_vmclear(struct kvm_vcpu *vcpu)
 /* Emulate the VMLAUNCH instruction */
 static int handle_vmlaunch(struct kvm_vcpu *vcpu)
 {
+	++vcpu->stat.vmlaunch_exits;
 	return nested_vmx_run(vcpu, true);
 }
 
@@ -5032,6 +5036,7 @@ static int handle_vmlaunch(struct kvm_vcpu *vcpu)
 static int handle_vmresume(struct kvm_vcpu *vcpu)
 {
 
+	++vcpu->stat.vmresume_exits;
 	return nested_vmx_run(vcpu, false);
 }
 
@@ -5049,6 +5054,8 @@ static int handle_vmread(struct kvm_vcpu *vcpu)
 	short offset;
 	int len, r;
 
+	++vcpu->stat.vmread_exits;
+
 	if (!nested_vmx_check_permission(vcpu))
 		return 1;
 
@@ -5141,6 +5148,8 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu)
 	 */
 	u64 value = 0;
 
+	++vcpu->stat.vmwrite_exits;
+
 	if (!nested_vmx_check_permission(vcpu))
 		return 1;
 
@@ -5245,6 +5254,8 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu)
 	gpa_t vmptr;
 	int r;
 
+	++vcpu->stat.vmptrld_exits;
+
 	if (!nested_vmx_check_permission(vcpu))
 		return 1;
 
@@ -5311,6 +5322,8 @@ static int handle_vmptrst(struct kvm_vcpu *vcpu)
 	gva_t gva;
 	int r;
 
+	++vcpu->stat.vmptrst_exits;
+
 	if (!nested_vmx_check_permission(vcpu))
 		return 1;
 
@@ -5351,6 +5364,8 @@ static int handle_invept(struct kvm_vcpu *vcpu)
 	} operand;
 	int i, r;
 
+	++vcpu->stat.invept_exits;
+
 	if (!(vmx->nested.msrs.secondary_ctls_high &
 	      SECONDARY_EXEC_ENABLE_EPT) ||
 	    !(vmx->nested.msrs.ept_caps & VMX_EPT_INVEPT_BIT)) {
@@ -5431,6 +5446,8 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
 	u16 vpid02;
 	int r;
 
+	++vcpu->stat.invvpid_exits;
+
 	if (!(vmx->nested.msrs.secondary_ctls_high &
 	      SECONDARY_EXEC_ENABLE_VPID) ||
 			!(vmx->nested.msrs.vpid_caps & VMX_VPID_INVVPID_BIT)) {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1a00af1b076b..c2c95b4c1a68 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -277,7 +277,18 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
 	STATS_DESC_COUNTER(VCPU, nested_run),
 	STATS_DESC_COUNTER(VCPU, directed_yield_attempted),
 	STATS_DESC_COUNTER(VCPU, directed_yield_successful),
-	STATS_DESC_ICOUNTER(VCPU, guest_mode)
+	STATS_DESC_ICOUNTER(VCPU, guest_mode),
+	STATS_DESC_COUNTER(VCPU, vmclear_exits),
+	STATS_DESC_COUNTER(VCPU, vmlaunch_exits),
+	STATS_DESC_COUNTER(VCPU, vmptrld_exits),
+	STATS_DESC_COUNTER(VCPU, vmptrst_exits),
+	STATS_DESC_COUNTER(VCPU, vmread_exits),
+	STATS_DESC_COUNTER(VCPU, vmresume_exits),
+	STATS_DESC_COUNTER(VCPU, vmwrite_exits),
+	STATS_DESC_COUNTER(VCPU, vmoff_exits),
+	STATS_DESC_COUNTER(VCPU, vmon_exits),
+	STATS_DESC_COUNTER(VCPU, invept_exits),
+	STATS_DESC_COUNTER(VCPU, invvpid_exits),
 };
 
 const struct kvm_stats_header kvm_vcpu_stats_header = {

base-commit: 47e7414d53fc12407b7a43bba412ecbf54c84f82
-- 
2.33.0.rc2.250.ged5fa647cd-goog