Re: [RFC PATCH 2/2] KVM: x86: use __kvm_guest_exit

From: Bandan Das
Date: Thu Jun 16 2016 - 18:01:50 EST


...
> static bool vmx_has_high_real_mode_segbase(void)
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 7e3041ef050f..cc741b68139c 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -6706,21 +6706,13 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
>
> kvm_put_guest_xcr0(vcpu);
>
> - /* Interrupt is enabled by handle_external_intr() */
> kvm_x86_ops->handle_external_intr(vcpu);
>
> ++vcpu->stat.exits;
>
> - /*
> - * We must have an instruction between local_irq_enable() and
> - * kvm_guest_exit(), so the timer interrupt isn't delayed by
> - * the interrupt shadow. The stat.exits increment will do nicely.
> - * But we need to prevent reordering, hence this barrier():
> - */
> - barrier();
> -
> - kvm_guest_exit();
> + __kvm_guest_exit();

kvm_guest_exit has no more callers and so can be removed.

Bandan

> + local_irq_enable();
> preempt_enable();
>
> vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);