Re: [PATCH 07/10] KVM: VMX: Clean up vmx_flush_tlb_gva()

From: Vitaly Kuznetsov
Date: Fri Feb 21 2020 - 08:54:50 EST


Sean Christopherson <sean.j.christopherson@xxxxxxxxx> writes:

> Refactor vmx_flush_tlb_gva() to remove a superfluous local variable and
> clean up its comment, which is oddly located below the code it is
> commenting.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> ---
> arch/x86/kvm/vmx/vmx.c | 10 +++-------
> 1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index 5372a93e1727..906e9d9aa09e 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -2824,15 +2824,11 @@ static void exit_lmode(struct kvm_vcpu *vcpu)
>
> static void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
> {
> - int vpid = to_vmx(vcpu)->vpid;
> -
> - vpid_sync_vcpu_addr(vpid, addr);
> -
> /*
> - * If VPIDs are not supported or enabled, then the above is a no-op.
> - * But we don't really need a TLB flush in that case anyway, because
> - * each VM entry/exit includes an implicit flush when VPID is 0.
> + * vpid_sync_vcpu_addr() is a nop if vmx->vpid==0, see the comment in
> + * vmx_flush_tlb_guest() for an explanation of why this is ok.

"OK" :-)

> */
> + vpid_sync_vcpu_addr(to_vmx(vcpu)->vpid, addr);
> }
>
> static void vmx_flush_tlb_guest(struct kvm_vcpu *vcpu)

Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

--
Vitaly