Re: [PATCH] xen/arm: Move static event channel feature to a separate module

[Julien Grall <julien@xxxxxxx>]

Hi Michal,

On 29/11/2023 18:41, Michal Orzel wrote:
> On 29/11/2023 18:17, Julien Grall wrote:
> > That said, I could settle on defining the two helpers in the *.c
> > directly because they are not meant to be used outside of a single *.c.
> >
> > Simarly...
> >
> > > diff --git a/xen/arch/arm/include/asm/static-evtchn.h 
> > > b/xen/arch/arm/include/asm/static-evtchn.h
> > > new file mode 100644
> > > index 000000000000..472673fae345
> > > --- /dev/null
> > > +++ b/xen/arch/arm/include/asm/static-evtchn.h
> > > @@ -0,0 +1,41 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > +
> > > +#ifndef __ASM_STATIC_EVTCHN_H_
> > > +#define __ASM_STATIC_EVTCHN_H_
> > > +
> > > +#ifdef CONFIG_STATIC_EVTCHN
> > > +
> > > +#include <xen/device_tree.h>
> > > +
> > > +#define STATIC_EVTCHN_NODE_SIZE_CELLS 2
> > ... this used to be defined in domain_build.c. AFAICT the only use is
> > now in static-evtchn.c. So why is it defined in the header?
> >
> > If this is moved in the *.c, then the header static-evtchn.h would only
> > contain alloc_static_evtchn(). This could be moved in domain_build.h or
> > setup.h (I don't have any preference).
> Apart from a prototype, we still need a stub. Therefore I would prefer to still 
> have a header (will
> be needed for future upgrades e.g. port exposure in fdt) and move the prototype 
> and a stub there (the macro
> I can move to *.c). It just looks better for me + we reduce ifdefery in 
> domain_build/setup.h.
> Would you be ok with that?
I don't much like headers containing just one prototype. But I can live 
with them if you think more will be added.
Cheers,

--
Julien Grall