Re: [Qemu-devel] [PATCH v3 1/2] vfio-ccw: add force unlimited prefetch property

[Halil Pasic]

On 05/25/2018 08:08 PM, Eric Blake wrote:
> On 05/25/2018 12:46 PM, Halil Pasic wrote:
>
> > > > +static inline void warn_once(bool *warned, const char *fmt, ...)
> > > > +{
> > > > +    va_list ap;
> > > > +
> > > > +    if (!warned || *warned) {
> > > > +        return;
> > > > +    }
> > > > +    *warned = true;
> > > > +    va_start(ap, fmt);
> > > > +    warn_vreport(fmt, ap);
> > > > +    va_end(ap);
> > > > +}
> > > > +
> > > > +static inline void warn_once_pfch(VFIOCCWDevice *vcdev, SubchDev *sch,
> > > > +                                  const char *msg)
> > > > +{
> > > > +    warn_once(&vcdev->warned_orb_pfch, "vfio-ccw (devno %x.%x.%04x): %s",
> > > > +              sch->cssid, sch->ssid, sch->devno, msg);
> > > > +}
> > > > +
> > >
> > > While I still think we want warn_once() in common error handling code,
> > > this looks reasonable enough. We can still move it later.
> >
> > I agree. I was a bit surprised to not find any warn_once functionality.
>
> That has been proposed:
> https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg05457.html

Thanks! I was not aware of this. If we were to use that we would
AFAIU have to transition to once-once instead of once per device
as done in my patch based on Connie's request.

Regards,
Halil