Re: [Qemu-devel] Re: [6684] Fix "info registers" under kvm.

[Anthony Liguori]

Avi Kivity wrote:
> Avi Kivity wrote:
> > Jan Kiszka wrote:
> > > I'm just still waiting for a reply from Anthony on how to embed best 
> > > all
> > > the "if (kvm_enabled()) foo();" patterns [2]. That would also allow us
> > > to merge gdbstub support for upstream kvm.
> > >
> > >   
> >
> > Wouldn't 'if (!kvm_enabled()) return;' inside the callees suffice?
>
> Rather,
>
> static inline void kvm_foo(...)
> {
>    if (!kvm_enabled()) {
>        return;
>    }
>
> #ifdef CONFIG_KVM
>   kvm_do_foo();
> #endif
> }

In the case of save/load registers, I'd prefer wrapper functions like:

cpu_state_update(CPUState *env, int is_dirty)

That could be hooked by something like Xen.  The implementation would be:

static void cpu_state_update(CPUState *env, int is_dirty)
{
   if (kvm_enabled()) {
       if (is_dirty)
          kvm_arch_save_registers(env);
       else
          kvm_arch_load_registers(env);
   }
}

Regards,

Anthony Liguori

>