Re: [patch V5 15/15] x86/kvm: Use generic xfer to guest work function

From: Sean Christopherson
Date: Thu Jul 23 2020 - 20:55:49 EST


On Fri, Jul 24, 2020 at 02:46:26AM +0200, Thomas Gleixner wrote:
> Sean,
>
> Sean Christopherson <sean.j.christopherson@xxxxxxxxx> writes:
> > On Thu, Jul 23, 2020 at 12:00:09AM +0200, Thomas Gleixner wrote:
> >> + if (xfer_to_guest_mode_work_pending()) {
> >> srcu_read_unlock(&kvm->srcu, vcpu->srcu_idx);
> >> - cond_resched();
> >> + r = xfer_to_guest_mode(vcpu);
> >
> > Any reason not to call this xfer_to_guest_mode_work()? Or handle_work(),
> > do_work(), etc... Without the "work" part, it looks like a function that
> > should be invoked unconditionally. It's obvious that's not the case if
> > one looks at the implementation, but it's a bit confusing on the KVM side
> > of things.
>
> The reason is probably lazyness. The original approach was to have this
> as close as possible to user entry/exit but with the recent changes
> vs. instrumentation and RCU this is not longer the case.
>
> I really want to keep the notion of transitioning in the function name,
> so xfer_to_guest_mode_handle_work() makes a lot of sense.
>
> I'll change that before merging the lot into the tip tree if your
> Reviewed-by still stands with that change made w/o reposting.

Ya, works for me.