Re: [PATCH v15 1/4] xen/arm: Implement PSCI SYSTEM_SUSPEND call for guests

[Mykola Kvach <xakep.amatop@xxxxxxxxx>]

Hi Jan,

Thank you for the review.

On Wed, Dec 3, 2025 at 12:11 PM Jan Beulich <jbeulich@xxxxxxxx> wrote:
>
> On 03.12.2025 10:57, Mykola Kvach wrote:
> > --- a/xen/common/domain.c
> > +++ b/xen/common/domain.c
> > @@ -26,6 +26,7 @@
> >  #include <xen/hypercall.h>
> >  #include <xen/delay.h>
> >  #include <xen/shutdown.h>
> > +#include <xen/suspend.h>
> >  #include <xen/percpu.h>
> >  #include <xen/multicall.h>
> >  #include <xen/rcupdate.h>
> > @@ -1363,6 +1364,9 @@ void domain_resume(struct domain *d)
> >
> >      spin_lock(&d->shutdown_lock);
> >
> > +    if ( arch_domain_resume(d) )
> > +        goto fail;
>
> In case I didn't ask before: You're after a boolean result here, yet ...
>
> > --- /dev/null
> > +++ b/xen/include/xen/suspend.h
> > @@ -0,0 +1,25 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +
> > +#ifndef XEN_SUSPEND_H
> > +#define XEN_SUSPEND_H
> > +
> > +#if __has_include(<asm/suspend.h>)
> > +#include <asm/suspend.h>
> > +#else
> > +static inline int arch_domain_resume(struct domain *d)
> > +{
> > +    return 0;
> > +}
> > +#endif
>
> ... int is being returned. Why?

Would you prefer I switch arch_domain_resume() to bool, or is keeping
int acceptable?

I lean toward keeping int: the generic call site is shared by all arches,
so future arches could inspect/handle specific error codes, and this matches
other arch hooks (e.g. arch_domain_teardown()) that are only checked for
"rc != 0" before bailing.

With int, I'll store the result and gate the rest:

    rc = arch_domain_resume(d);
    if (rc)
        goto fail;

If int works for you, I’ll keep it; otherwise I can flip to bool.

>
> Jan

Best regards,
Mykola