KVM: x86: Move kvm_{before,after}_interrupt() calls to vendor code

VMX can conditionally call kvm_{before,after}_interrupt() since KVM
always uses "ack interrupt on exit" and therefore explicitly handles
interrupts as opposed to blindly enabling irqs.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/svm.c

@@ -6174,6 +6174,7 @@ static int svm_check_intercept(struct kvm_vcpu *vcpu,
 
 static void svm_handle_external_intr(struct kvm_vcpu *vcpu)
 {
+	kvm_before_interrupt(vcpu);
 	local_irq_enable();
 	/*
 	 * We must have an instruction with interrupts enabled, so
@@ -6181,6 +6182,7 @@ static void svm_handle_external_intr(struct kvm_vcpu *vcpu)
 	 */
 	asm("nop");
 	local_irq_disable();
+	kvm_after_interrupt(vcpu);
 }
 
 static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)

arch/x86/kvm/vmx/vmx.c

@@ -6145,6 +6145,8 @@ static void vmx_handle_external_intr(struct kvm_vcpu *vcpu)
 	desc = (gate_desc *)host_idt_base + vector;
 	entry = gate_offset(desc);
 
+	kvm_before_interrupt(vcpu);
+
 	asm volatile(
 #ifdef CONFIG_X86_64
 		"mov %%" _ASM_SP ", %[sp]\n\t"
@@ -6165,6 +6167,8 @@ static void vmx_handle_external_intr(struct kvm_vcpu *vcpu)
 		[ss]"i"(__KERNEL_DS),
 		[cs]"i"(__KERNEL_CS)
 	);
+
+	kvm_after_interrupt(vcpu);
 }
 STACK_FRAME_NON_STANDARD(vmx_handle_external_intr);
 

arch/x86/kvm/x86.c

@@ -7999,9 +7999,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 	vcpu->mode = OUTSIDE_GUEST_MODE;
 	smp_wmb();
 
-	kvm_before_interrupt(vcpu);
 	kvm_x86_ops->handle_external_intr(vcpu);
-	kvm_after_interrupt(vcpu);
 
 	++vcpu->stat.exits;