Re: [PATCH RFC v3 7/9] KVM: add kvm_free_vcpus and kvm_arch_free_vcpus

Cornelia Huck
2017-08-29T13:00:44Z

On Tue, 22 Aug 2017 16:18:59 +0200
David Hildenbrand <david@redhat.com> wrote:

> > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> > index 33a15e176927..0d2d8b0c785c 100644
> > --- a/virt/kvm/kvm_main.c
> > +++ b/virt/kvm/kvm_main.c
> > @@ -750,6 +750,23 @@ static void kvm_destroy_devices(struct kvm *kvm)
> > }
> > }
> >
> > +void kvm_free_vcpus(struct kvm *kvm)
> > +{
> > + int i;
> > +
> > + kvm_arch_free_vcpus(kvm);
>
> I wonder if it would be possible to get rid of kvm_arch_free_vcpus(kvm)
> completely and simply call
>
> kvm_for_each_vcpu(i, vcpu, kvm)
> kvm_arch_vcpu_free(vcpu);
>
> at that point.
>
> Would certainly require some refactoring, and I am not sure if we could
> modify the special mmu handling for x86 ("Unpin any mmu pages first.").
> But if in doubt, that part could be moved to kvm_arch_destroy_vm(), just
> before calling kvm_free_vcpus().

Nod, that crossed my mind as well. Would avoid adding lots of
kvm_arch_free_vcpus() that do the same thing for many archs.