Re: [PATCH v11 09/11] s390x/cpu topology: add topology machine property

[Pierre Morel]

On 11/15/22 14:48, Cédric Le Goater wrote:
> On 11/3/22 18:01, Pierre Morel wrote:
> > We keep the possibility to switch on/off the topology on newer
> > machines with the property topology=[on|off].
>
> The code has changed. You will need to rebase. May be after the
> 8.0 machine is introduced, or include Cornelia's patch in the
> respin.
>
> 20221111124534.129111-1-cohuck@redhat.com/">https://lore.kernel.org/qemu-devel/20221111124534.129111-1-cohuck@redhat.com/
>
> > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> > ---
> >   include/hw/boards.h                |  3 +++
> >   include/hw/s390x/cpu-topology.h    |  8 +++-----
> >   include/hw/s390x/s390-virtio-ccw.h |  1 +
> >   hw/core/machine.c                  |  3 +++
> >   hw/s390x/cpu-topology.c            | 19 +++++++++++++++++++
> >   hw/s390x/s390-virtio-ccw.c         | 28 ++++++++++++++++++++++++++++
> >   util/qemu-config.c                 |  4 ++++
> >   qemu-options.hx                    |  6 +++++-
> >   8 files changed, 66 insertions(+), 6 deletions(-)
> >
> > diff --git a/include/hw/boards.h b/include/hw/boards.h
> > index 311ed17e18..67147c47bf 100644
> > --- a/include/hw/boards.h
> > +++ b/include/hw/boards.h
> > @@ -379,6 +379,9 @@ struct MachineState {
> >       } \
> >       type_init(machine_initfn##_register_types)
> > +extern GlobalProperty hw_compat_7_2[];
> > +extern const size_t hw_compat_7_2_len;
> > +
> >   extern GlobalProperty hw_compat_7_1[];
> >   extern const size_t hw_compat_7_1_len;
> > diff --git a/include/hw/s390x/cpu-topology.h 
> > b/include/hw/s390x/cpu-topology.h
> > index 6fec10e032..f566394302 100644
> > --- a/include/hw/s390x/cpu-topology.h
> > +++ b/include/hw/s390x/cpu-topology.h
> > @@ -12,6 +12,8 @@
> >   #include "hw/qdev-core.h"
> >   #include "qom/object.h"
> > +#include "cpu.h"
> > +#include "hw/s390x/s390-virtio-ccw.h"
> >   #define S390_TOPOLOGY_CPU_IFL 0x03
> >   #define S390_TOPOLOGY_MAX_ORIGIN ((63 + S390_MAX_CPUS) / 64)
> > @@ -38,10 +40,6 @@ struct S390Topology {
> >   OBJECT_DECLARE_SIMPLE_TYPE(S390Topology, S390_CPU_TOPOLOGY)
> >   void s390_topology_new_cpu(S390CPU *cpu);
> > -
> > -static inline bool s390_has_topology(void)
> > -{
> > -    return false;
> > -}
> > +bool s390_has_topology(void);
> >   #endif
> > diff --git a/include/hw/s390x/s390-virtio-ccw.h 
> > b/include/hw/s390x/s390-virtio-ccw.h
> > index 89fca3f79f..d7602aedda 100644
> > --- a/include/hw/s390x/s390-virtio-ccw.h
> > +++ b/include/hw/s390x/s390-virtio-ccw.h
> > @@ -28,6 +28,7 @@ struct S390CcwMachineState {
> >       bool dea_key_wrap;
> >       bool pv;
> >       bool zpcii_disable;
> > +    bool cpu_topology;
> >       uint8_t loadparm[8];
> >       void *topology;
> >   };
> > diff --git a/hw/core/machine.c b/hw/core/machine.c
> > index aa520e74a8..4f46d4ef23 100644
> > --- a/hw/core/machine.c
> > +++ b/hw/core/machine.c
> > @@ -40,6 +40,9 @@
> >   #include "hw/virtio/virtio-pci.h"
> >   #include "qom/object_interfaces.h"
> > +GlobalProperty hw_compat_7_2[] = {};
> > +const size_t hw_compat_7_2_len = G_N_ELEMENTS(hw_compat_7_2);
> > +
> >   GlobalProperty hw_compat_7_1[] = {};
> >   const size_t hw_compat_7_1_len = G_N_ELEMENTS(hw_compat_7_1);
> > diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
> > index fc220bd8ac..c1550cc1e8 100644
> > --- a/hw/s390x/cpu-topology.c
> > +++ b/hw/s390x/cpu-topology.c
> > @@ -73,6 +73,25 @@ void s390_handle_ptf(S390CPU *cpu, uint8_t r1, 
> > uintptr_t ra)
> >       }
> >   }
> > +bool s390_has_topology(void)
> > +{
> > +    static S390CcwMachineState *ccw;
> > +    Object *obj;
> > +
> > +    if (ccw) {
> > +        return ccw->cpu_topology;
>
> Shouldn't we test the capability also ?
>
>      return s390mc->topology_capable && ccw->cpu_topology;

yes thanks

> > +    }
> > +
> > +    /* we have to bail out for the "none" machine */
> > +    obj = object_dynamic_cast(qdev_get_machine(),
> > +                              TYPE_S390_CCW_MACHINE);
> > +    if (!obj) {
> > +        return false;
> > +    }
>
> Should be an assert I think.

OK

> > +    ccw = S390_CCW_MACHINE(obj);
> > +    return ccw->cpu_topology;
> > +}
> > +
> >   /*
> >    * s390_topology_new_cpu:
> >    * @cpu: a pointer to the new CPU
> > diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> > index f1a9d6e793..ebb5615337 100644
> > --- a/hw/s390x/s390-virtio-ccw.c
> > +++ b/hw/s390x/s390-virtio-ccw.c
> > @@ -710,6 +710,26 @@ bool hpage_1m_allowed(void)
> >       return get_machine_class()->hpage_1m_allowed;
> >   }
> > +static inline bool machine_get_topology(Object *obj, Error **errp)
> > +{
> > +    S390CcwMachineState *ms = S390_CCW_MACHINE(obj);
> > +
> > +    return ms->cpu_topology;
> > +}
> > +
> > +static inline void machine_set_topology(Object *obj, bool value, 
> > Error **errp)
> > +{
> > +    S390CcwMachineState *ms = S390_CCW_MACHINE(obj);
>
> You could introduce :
>
>         S390CcwMachineClass *s390mc = S390_CCW_MACHINE_GET_CLASS(ms);

Yes thanks

> > +
> > +    if (!get_machine_class()->topology_capable) {
>
> and
>              !s390mc->topology_capable
>
> > +        error_setg(errp, "Property cpu-topology not available on 
> > machine %s",
> > +                   get_machine_class()->parent_class.name);
> > +        return;
> > +    }
> > +
> > +    ms->cpu_topology = value;
> > +}
> > +
> >   static void machine_get_loadparm(Object *obj, Visitor *v,
> >                                    const char *name, void *opaque,
> >                                    Error **errp)
> > @@ -809,6 +829,12 @@ static void ccw_machine_class_init(ObjectClass 
> > *oc, void *data)
> >                                      machine_set_zpcii_disable);
> >       object_class_property_set_description(oc, "zpcii-disable",
> >               "disable zPCI interpretation facilties");
> > +
> > +    object_class_property_add_bool(oc, "topology",
> > +                                   machine_get_topology,
> > +                                   machine_set_topology);
> > +    object_class_property_set_description(oc, "topology",
> > +            "enable CPU topology");
> >   }
> >   static inline void s390_machine_initfn(Object *obj)
> > @@ -818,6 +844,7 @@ static inline void s390_machine_initfn(Object *obj)
> >       ms->aes_key_wrap = true;
> >       ms->dea_key_wrap = true;
> >       ms->zpcii_disable = false;
> > +    ms->cpu_topology = true;
> >   }
> >   static const TypeInfo ccw_machine_info = {
> > @@ -888,6 +915,7 @@ static void 
> > ccw_machine_7_1_instance_options(MachineState *machine)
> >       s390_cpudef_featoff_greater(16, 1, S390_FEAT_PAIE);
> >       s390_set_qemu_cpu_model(0x8561, 15, 1, qemu_cpu_feat);
> >       ms->zpcii_disable = true;
> > +    ms->cpu_topology = true;
>
> shouldn't this be false ?

:) yes
I forgot to change this when I change the logic.

Thanks,
Pierre

--
Pierre Morel
IBM Lab Boeblingen