Re: [PATCH v2 1/4] accel: Introduce 'query-accels' QMP command

[Eric Blake <eblake@redhat.com>]

On 3/16/21 12:24 PM, Philippe Mathieu-Daudé wrote:
> 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.
> 

> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> Since v1: 'type' -> 'name' in comments
> ---
>  qapi/machine.json | 55 +++++++++++++++++++++++++++++++++++++++++++++++
>  accel/accel-qmp.c | 49 +++++++++++++++++++++++++++++++++++++++++
>  accel/meson.build |  2 +-
>  3 files changed, 105 insertions(+), 1 deletion(-)
>  create mode 100644 accel/accel-qmp.c
> 
> diff --git a/qapi/machine.json b/qapi/machine.json
> index 330189efe3d..610252fc25c 100644
> --- a/qapi/machine.json
> +++ b/qapi/machine.json
> @@ -1471,3 +1471,58 @@
>  ##
>  { 'event': 'MEM_UNPLUG_ERROR',
>    'data': { 'device': 'str', 'msg': 'str' } }
> +
> +##
> +# @Accelerator:
> +#
> +# An enumeration of accelerator names.
> +#
> +# Since: 6.0
> +##
> +{ 'enum': 'Accelerator',
> +  'data': [ { 'name': 'qtest' },
> +            { 'name': 'tcg' },
> +            { 'name': 'kvm' },
> +            { 'name': 'hax' },
> +            { 'name': 'hvf' },
> +            { 'name': 'whpx' },
> +            { 'name': 'xen' } ] }

Shorter, but semantically equivalent:
{ 'enum': 'Accelerator', 'data': [ 'qtest', 'tcg', ... ] }

I'd mention in the commit message body that we can't make the enum
values or union branches conditional because of target-specific
poisoning.  With that,

Reviewed-by: Eric Blake <eblake@redhat.com>

If we're trying to get it into 6.0, it is a new feature, and so we
should get it in a pull request before feature freeze today.  Otherwise
we'll have to s/6.0/6.1/

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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