Re: [PATCH v15 18/23] accel: introduce AccelCPUClass extending CPUClass

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 2/1/21 11:08 AM, Claudio Fontana wrote:
> add a new optional interface to CPUClass, which allows accelerators
> to extend the CPUClass with additional accelerator-specific
> initializations.
> 
> Signed-off-by: Claudio Fontana <cfontana@suse.de>
> ---
>  include/hw/core/accel-cpu.h | 35 +++++++++++++++++++++++++++++
>  include/hw/core/cpu.h       |  1 +
>  accel/accel-common.c        | 44 +++++++++++++++++++++++++++++++++++++
>  MAINTAINERS                 |  1 +
>  4 files changed, 81 insertions(+)
>  create mode 100644 include/hw/core/accel-cpu.h
> 
> diff --git a/include/hw/core/accel-cpu.h b/include/hw/core/accel-cpu.h
> new file mode 100644
> index 0000000000..c7c137dc9a
> --- /dev/null
> +++ b/include/hw/core/accel-cpu.h
> @@ -0,0 +1,35 @@
> +/*
> + * Accelerator interface, specializes CPUClass
> + *
> + * Copyright 2021 SUSE LLC
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#ifndef ACCEL_CPU_H
> +#define ACCEL_CPU_H
> +
> +/*
> + * these defines cannot be in cpu.h, because we are using
> + * CPU_RESOLVING_TYPE here.
> + * Use this header to define your accelerator-specific
> + * cpu-specific accelerator interfaces.
> + */
> +
> +#define TYPE_ACCEL_CPU "accel-" CPU_RESOLVING_TYPE
> +#define ACCEL_CPU_NAME(name) (name "-" TYPE_ACCEL_CPU)
> +typedef struct AccelCPUClass AccelCPUClass;
> +DECLARE_CLASS_CHECKERS(AccelCPUClass, ACCEL_CPU, TYPE_ACCEL_CPU)
> +
> +typedef struct AccelCPUClass {
> +    /*< private >*/
> +    ObjectClass parent_class;
> +    /*< public >*/
> +
> +    void (*cpu_class_init)(CPUClass *cc);
> +    void (*cpu_instance_init)(CPUState *cpu);
> +    void (*cpu_realizefn)(CPUState *cpu, Error **errp);
> +} AccelCPUClass;

This header only makes sense if you forward-declare CPUClass
in "qemu/typedefs.h", so accelerators don't have to include
"hw/core/cpu.h".