Re: [Qemu-arm] [Qemu-devel] [PATCH RFC 07/16] qom/cpu: make nr-cores, nr-threads real properties

[Andrew Jones]

On Sat, Jun 11, 2016 at 08:54:35AM +0200, Thomas Huth wrote:
> On 10.06.2016 19:40, Andrew Jones wrote:
> > Signed-off-by: Andrew Jones <address@hidden>
> > ---
> >  qom/cpu.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/qom/cpu.c b/qom/cpu.c
> > index 751e992de8823..024cda3eb98c8 100644
> > --- a/qom/cpu.c
> > +++ b/qom/cpu.c
> > @@ -28,6 +28,7 @@
> >  #include "exec/log.h"
> >  #include "qemu/error-report.h"
> >  #include "sysemu/sysemu.h"
> > +#include "hw/qdev-properties.h"
> >  
> >  bool cpu_exists(int64_t id)
> >  {
> > @@ -342,6 +343,12 @@ static int64_t cpu_common_get_arch_id(CPUState *cpu)
> >      return cpu->cpu_index;
> >  }
> >  
> > +static Property cpu_common_properties[] = {
> > +    DEFINE_PROP_INT32("nr-cores", CPUState, nr_cores, 1),
> > +    DEFINE_PROP_INT32("nr-threads", CPUState, nr_threads, 1),
> > +    DEFINE_PROP_END_OF_LIST()
> > +};
> 
> Are you aware of the current CPU hotplug discussion that is going on?

I'm aware of it going on, but haven't been following it.

> I'm not very involved there, but I think some of these reworks also move
> "nr_threads" into the CPU state already, e.g. see:

nr_threads (and nr_cores) are already state in CPUState. This patch just
exposes that state via properties.

> 
> https://github.com/dgibson/qemu/commit/9d07719784ecbeebea71
> 
> ... so you might want to check these patches first to see whether you
> can base your rework on them?

Every cpu, and thus every machine, uses CPUState for its cpus. I'm
not sure every machine will want to use that new abstract core class
though. If they did, then we could indeed use nr_threads from there
instead (and remove it from CPUState), but we'd still need nr_cores
from the abstract cpu package class (CPUState).

Thanks,
drew