linux-kernel - [RESEND PATCH 01/13] KVM: x86: Relocate MMIO exit stats counting

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Date:   Thu, 22 Aug 2019 18:06:57 -0700
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>
Cc:     Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [RESEND PATCH 01/13] KVM: x86: Relocate MMIO exit stats counting

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.

Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 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