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

[Pierre Morel <pmorel@linux.ibm.com>]

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.
> 
> 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