[PATCH v2 01/14] KVM: x86: Relocate MMIO exit stats counting

From: Sean Christopherson
Date: Tue Aug 27 2019 - 17:42:06 EST


Move the stat.mmio_exits update into x86_emulate_instruction(). This is
both a bug fix, e.g. the current update flows will incorrectly increment
mmio_exits on emulation failure, and a preparatory change to set the
stage for eliminating EMULATE_DONE and company.

Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
---
arch/x86/kvm/mmu.c | 2 --
arch/x86/kvm/vmx/vmx.c | 1 -
arch/x86/kvm/x86.c | 2 ++
3 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 4c45ff0cfbd0..845e39d8a970 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -5437,8 +5437,6 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u64 error_code,
case EMULATE_DONE:
return 1;
case EMULATE_USER_EXIT:
- ++vcpu->stat.mmio_exits;
- /* fall through */
case EMULATE_FAIL:
return 0;
default:
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 570a233e272b..18286e5b5983 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5200,7 +5200,6 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
err = kvm_emulate_instruction(vcpu, 0);

if (err == EMULATE_USER_EXIT) {
- ++vcpu->stat.mmio_exits;
ret = 0;
goto out;
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b4cfd786d0b6..cd425f54096a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6598,6 +6598,8 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu,
}
r = EMULATE_USER_EXIT;
} else if (vcpu->mmio_needed) {
+ ++vcpu->stat.mmio_exits;
+
if (!vcpu->mmio_is_write)
writeback = false;
r = EMULATE_USER_EXIT;
--
2.22.0