Re: [PATCH 3/5] hw/core: Remove uses of QERR_DEVICE_NO_HOTPLUG

[Damien Hedde <damien.hedde@greensocs.com>]

On 11/19/21 09:20, Markus Armbruster wrote:
> Philippe Mathieu-Daudé <philmd@redhat.com> writes:
> 
>> QERR_DEVICE_NO_HOTPLUG definition is obsolete since 2015 (commit
>> 4629ed1e989, "qerror: Finally unused, clean up"). Replace the two
>> uses and drop the definition.
>>
>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>> ---
>>   include/qapi/qmp/qerror.h | 3 ---
>>   hw/core/qdev.c            | 3 ++-
>>   softmmu/qdev-monitor.c    | 2 +-
>>   3 files changed, 3 insertions(+), 5 deletions(-)
>>
>> diff --git a/include/qapi/qmp/qerror.h b/include/qapi/qmp/qerror.h
>> index 596fce0c54e..f49ae01cdb0 100644
>> --- a/include/qapi/qmp/qerror.h
>> +++ b/include/qapi/qmp/qerror.h
>> @@ -26,9 +26,6 @@
>>   #define QERR_DEVICE_IN_USE \
>>       "Device '%s' is in use"
>>   
>> -#define QERR_DEVICE_NO_HOTPLUG \
>> -    "Device '%s' does not support hotplugging"
>> -
>>   #define QERR_FEATURE_DISABLED \
>>       "The feature '%s' is not enabled"
>>   
>> diff --git a/hw/core/qdev.c b/hw/core/qdev.c
>> index 7f06403752d..14375861c36 100644
>> --- a/hw/core/qdev.c
>> +++ b/hw/core/qdev.c
>> @@ -734,7 +734,8 @@ static void device_set_realized(Object *obj, bool value, Error **errp)
>>       static int unattached_count;
>>   
>>       if (dev->hotplugged && !dc->hotpluggable) {
>> -        error_setg(errp, QERR_DEVICE_NO_HOTPLUG, object_get_typename(obj));
>> +        error_setg(errp, "Device '%s' does not support hotplugging",
>> +                   object_get_typename(obj));
>>           return;
>>       }
>>   
>> diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c
>> index 4851de51a5c..35a885a6623 100644
>> --- a/softmmu/qdev-monitor.c
>> +++ b/softmmu/qdev-monitor.c
>> @@ -896,7 +896,7 @@ void qdev_unplug(DeviceState *dev, Error **errp)
>>       }
>>   
>>       if (!dc->hotpluggable) {
>> -        error_setg(errp, QERR_DEVICE_NO_HOTPLUG,
>> +        error_setg(errp, "Device '%s' does not support hotplugging",
>>                      object_get_typename(OBJECT(dev)));
>>           return;
>>       }
> 
> When the same error is detected in multiple places, I like to ask myself
> whether the code calls for a refactoring.  But I can't see a useful one
> here.
> 

Since the realize check will catch more case (devices created 
recursively by a command or simply by C code), we could remove the 
softmmu/qdev-monitor.c check and rely on realize catching that just after.
In theory failing during realize should have the same result as "not 
trying to create the device in the first place".

--
Damien