Re: [Qemu-devel] [PATCH 10/16] target-i386: introduce apic-id property

["Andreas Färber" <afaerber@suse.de>]

Am 22.04.2013 18:30, schrieb Igor Mammedov:
> On Mon, 22 Apr 2013 16:05:34 +0200
> Andreas Färber <afaerber@suse.de> wrote:
> 
>> Am 16.04.2013 00:12, schrieb Igor Mammedov:
>>> ... and use it from board level to set APIC ID for CPUs
>>> it creates.
>>>
>>> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
>>> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
>>> ---
>>> Note:
>>>   * pc_new_cpu() function will be reused later in CPU hot-plug hook.
>>
>> Suggest as main commit message to avoid the "...":
>>
>> The property is used from board level to set APIC ID for CPUs it
>> creates. Do so in a new pc_new_cpu() helper, to be reused for hot-plug.
> I'll do on next respin.
> 
>>>
>>> v3:
>>>   * user error_propagate() in property setter
>>> v2:
>>>   * use generic cpu_exists() instead of custom one
>>>   * make apic-id dynamic property, so it won't be possible to use it
>>>     as global property, since it's instance specific
>>> ---
>>>  hw/i386/pc.c      | 25 ++++++++++++++++++++++++-
>>>  target-i386/cpu.c | 42 ++++++++++++++++++++++++++++++++++++++++++
>>>  2 files changed, 66 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>>> index dc1a78b..cb57878 100644
>>> --- a/hw/i386/pc.c
>>> +++ b/hw/i386/pc.c
>>> @@ -889,9 +889,29 @@ void pc_acpi_smi_interrupt(void *opaque, int irq,
>>> int level) }
>>>  }
>>>  
>>> +static void pc_new_cpu(const char *cpu_model, int64_t apic_id, Error
>>> **errp) +{
>>> +    X86CPU *cpu;
>>> +
>>> +    cpu = cpu_x86_create(cpu_model, errp);
>>> +    if (!cpu) {
>>> +        return;
>>> +    }
>>> +
>>> +    object_property_set_int(OBJECT(cpu), apic_id, "apic-id", errp);
>>> +    object_property_set_bool(OBJECT(cpu), true, "realized", errp);
>>> +
>>> +    if (error_is_set(errp)) {
>>
>> Please use a local Error* variable with error_propagate, otherwise this
>> is fragile.
> done
> 
>>
>>> +        if (cpu != NULL) {
>>> +            object_unref(OBJECT(cpu));
>>> +        }
>>> +    }
>>> +}
>>> +
>>>  void pc_cpus_init(const char *cpu_model)
>>>  {
>>>      int i;
>>> +    Error *error = NULL;
>>>  
>>>      /* init CPUs */
>>>      if (cpu_model == NULL) {
>>> @@ -903,7 +923,10 @@ void pc_cpus_init(const char *cpu_model)
>>>      }
>>>  
>>>      for (i = 0; i < smp_cpus; i++) {
>>> -        if (!cpu_x86_init(cpu_model)) {
>>> +        pc_new_cpu(cpu_model, x86_cpu_apic_id_from_index(i), &error);
>>> +        if (error) {
>>> +            fprintf(stderr, "%s\n", error_get_pretty(error));
>>> +            error_free(error);
>>>              exit(1);
>>>          }
>>>      }
>>> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
>>> index a415fa3..6d6c527 100644
>>> --- a/target-i386/cpu.c
>>> +++ b/target-i386/cpu.c
>>> @@ -1271,6 +1271,45 @@ static void x86_cpuid_set_tsc_freq(Object *obj,
>>> Visitor *v, void *opaque, cpu->env.tsc_khz = value / 1000;
>>>  }
>>>  
>>> +static void x86_cpuid_get_apic_id(Object *obj, Visitor *v, void *opaque,
>>> +                                  const char *name, Error **errp)
>>> +{
>>> +    X86CPU *cpu = X86_CPU(obj);
>>> +    int64_t value = cpu->env.cpuid_apic_id;
>>> +
>>> +    visit_type_int(v, &value, name, errp);
>>> +}
>>> +
>>> +static void x86_cpuid_set_apic_id(Object *obj, Visitor *v, void *opaque,
>>> +                                  const char *name, Error **errp)
>>> +{
>>> +    X86CPU *cpu = X86_CPU(obj);
>>> +    const int64_t min = 0;
>>> +    const int64_t max = UINT32_MAX;
>>> +    Error *error = NULL;
>>> +    int64_t value;
>>> +
>>> +    visit_type_int(v, &value, name, &error);
>>> +    if (error) {
>>> +        error_propagate(errp, error);
>>> +        return;
>>> +    }
>>
>>> +    if (value < min || value > max) {
>>> +        error_setg(&error, "Property %s.%s doesn't take value %" PRId64
>>> +                   " (minimum: %" PRId64 ", maximum: %" PRId64 ")" ,
>>> +                   object_get_typename(obj), name, value, min, max);
>>> +        error_propagate(errp, error);
>>> +        return;
>>> +    }
>>> +
>>> +    if (cpu_exists(value)) {
>>> +        error_setg(&error, "CPU with APIC ID %" PRIi64 " exists", value);
>>> +        error_propagate(errp, error);
>>
>> You could do both error_setg()s directly on errp.
> it was so before, but I was requested to use local error here:
> http://lists.gnu.org/archive/html/qemu-devel/2013-04/msg01606.html

The only thing Paolo requested there (and which I +1) is not to do
error_is_set(errp). That is independent of error_setg() though, which is
followed by a return, so has no functional difference.

Andreas

> 
>>
>>> +        return;
>>> +    }
>>> +    cpu->env.cpuid_apic_id = value;
>>> +}
>>> +
>>>  static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *name)
>>>  {
>>>      x86_def_t *def;
>>> @@ -2259,6 +2298,9 @@ static void x86_cpu_initfn(Object *obj)
>>>      object_property_add(obj, "tsc-frequency", "int",
>>>                          x86_cpuid_get_tsc_freq,
>>>                          x86_cpuid_set_tsc_freq, NULL, NULL, NULL);
>>> +    object_property_add(obj, "apic-id", "int",
>>> +                        x86_cpuid_get_apic_id,
>>> +                        x86_cpuid_set_apic_id, NULL, NULL, NULL);
>>>  
>>>      env->cpuid_apic_id = x86_cpu_apic_id_from_index(cs->cpu_index);
>>>  
>>
>> Otherwise I like this x86-specific version now!
>>
>> Andreas
>>
> 
> 


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