Re: [PATCH v16 02/99] accel: Introduce 'query-accels' QMP command

[Philippe Mathieu-Daudé]

On 6/7/21 3:07 PM, Thomas Huth wrote:
> On 04/06/2021 17.51, Alex Bennée wrote:
>> From: Philippe Mathieu-Daudé <philmd@redhat.com>
>>
>> Introduce the 'query-accels' QMP command which returns a list
>> of built-in accelerator names.
>>
>> - Accelerator is a QAPI enum of all existing accelerators,
>>
>> - AcceleratorInfo is a QAPI structure providing accelerator
>>    specific information. Currently the common structure base
>>    provides the name of the accelerator, while the specific
>>    part is empty, but each accelerator can expand it.
>>
>> - 'query-accels' QMP command returns a list of @AcceleratorInfo
>>
>> For example on a KVM-only build we get:
>>
>>      { "execute": "query-accels" }
>>      {
>>          "return": [
>>              {
>>                  "name": "qtest"
>>              },
>>              {
>>                  "name": "kvm"
>>              }
>>          ]
>>      }
>>
>> Note that we can't make the enum values or union branches conditional
>> because of target-specific poisoning of accelerator definitions.
>>
>> Reviewed-by: Eric Blake <eblake@redhat.com>
>> Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
>> Tested-by: Alex Bennée <alex.bennee@linaro.org>
>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
>> Message-Id: <20210505125806.1263441-3-philmd@redhat.com>
>> ---
> [...]
>> +static const bool accel_builtin_list[ACCELERATOR__MAX] = {
>> +    [ACCELERATOR_QTEST] = true,
>> +#ifdef CONFIG_TCG
>> +    [ACCELERATOR_TCG] = true,
>> +#endif
>> +#ifdef CONFIG_KVM
>> +    [ACCELERATOR_KVM] = true,
>> +#endif
>> +#ifdef CONFIG_HAX
>> +    [ACCELERATOR_HAX] = true,
>> +#endif
>> +#ifdef CONFIG_HVF
>> +    [ACCELERATOR_HVF] = true,
>> +#endif
>> +#ifdef CONFIG_WHPX
>> +    [ACCELERATOR_WHPX] = true,
>> +#endif
>> +#ifdef CONFIG_XEN_BACKEND
>> +    [ACCELERATOR_XEN] = true,
>> +#endif
> 
> Nit: Use alphabetical order here, too, just like you did in the enum?

This has been drastically simplified by Markus using target-specific
machine code in v8.