On Fri, 23 Jan 2026 16:16:03 +0000
Jonathan Cameron via qemu development <[email protected]> wrote:
> > >
> > > > + for i in range(0, attempts):
> > > > + try:
> > > > + obj = self.qmp_monitor.cmd_obj(msg)
> > > > +
> > > > + if obj and "return" in obj and not obj["return"]:
> > > > + break
> > > > +
> > > > + except Exception as e: # pylint:
> > > > disable=W0718
> > > > + print(f"Command: {command}")
> > > > + print(f"Failed to inject error: {e}.")
> > > > + obj = None
> > > > +
> > > > + if attempts > 1:
> > > > + print(f"Error inject attempt {i + 1}/{attempts}
> > > > failed.")
> > > > +
> > > > + if i + 1 < attempts:
> > > > + sleep(0.1)
> >
> > ... and here, we sleep for 0.1 seconds.
> >
> > >
> > > Do we care about a sleep at the end? Feels like a micro optimization that
> > > isn't needed.
> >
> > This is not a micro-optimization. It is more to ensure that we won't
> > respin it too fast.
> >
> > What happens is that QMP interface asks the BIOS to send an async
> > message to OSPM, cleaning an ack register. When the OSPM reads the
> > error, it writes 1 to the ack register.
> >
> > If we send messages too fast, the logic at ghes.c will detect that
> > the ack didn't happen, imediately returning an errocr code.
> >
> > On such case, we sleep for 100ms before trying again.
> I was suggesting the opposite. Just sleep one more time at the end
> before timing out.
> So instead of
> if i + 1 < attempts
> sleep(0.1)
>
> simply
> sleep(0.1)
If one writes an external loop calling fuzzy with different parameters,
like:
for i in $(seq 1 360000); do
scripts/ghes_inject.py fuzzy -T proc-arm;
scripts/ghes_inject.py fuzzy -T firmware-error;
done
The extra unneeded would sleep waste 10 hours doing nothing.
Regards,
Mauro
