Re: [RFC V1 04/14] accel: set accelerator and machine props earlier

[Peter Xu <peterx@redhat.com>]

On Thu, Oct 17, 2024 at 08:14:05AM -0700, Steve Sistare wrote:
> Make all global and compat properties available before the first objects
> are created.  Set accelerator compatibility properties in
> configure_accelerators, when the accelerator is chosen, and call
> configure_accelerators earlier.  Set machine options earlier.
> 
> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> ---
>  accel/accel-system.c |  2 --
>  system/vl.c          | 34 ++++++++++++++++++----------------
>  2 files changed, 18 insertions(+), 18 deletions(-)
> 
> diff --git a/accel/accel-system.c b/accel/accel-system.c
> index f6c947d..c8aeae4 100644
> --- a/accel/accel-system.c
> +++ b/accel/accel-system.c
> @@ -41,8 +41,6 @@ int accel_init_machine(AccelState *accel, MachineState *ms)
>          ms->accelerator = NULL;
>          *(acc->allowed) = false;
>          object_unref(OBJECT(accel));
> -    } else {
> -        object_set_accelerator_compat_props(acc->compat_props);
>      }
>      return ret;
>  }
> diff --git a/system/vl.c b/system/vl.c
> index b94a6b9..bca2292 100644
> --- a/system/vl.c
> +++ b/system/vl.c
> @@ -2346,6 +2346,7 @@ static int do_configure_accelerator(void *opaque, QemuOpts *opts, Error **errp)
>          goto bad;
>      }
>  
> +    object_set_accelerator_compat_props(ac->compat_props);

This is the probe/preinit iterator, might be good to keep it simple to only
make the decision of choosing one accel, then move this line over to
configure_accelerators() at the end.

>      acs->accel = accel;
>      return 1;
>  
> @@ -3728,29 +3729,14 @@ void qemu_init(int argc, char **argv)
>      parse_memory_options();
>  
>      qemu_create_machine(machine_opts_dict);
> -
> -    suspend_mux_open();
> -
> -    qemu_disable_default_devices();
> -    qemu_setup_display();
> -    qemu_create_default_devices();
> -    qemu_create_early_backends();
> -
>      qemu_apply_legacy_machine_options(machine_opts_dict);
>      qemu_apply_machine_options(machine_opts_dict);
>      qobject_unref(machine_opts_dict);
> -    phase_advance(PHASE_MACHINE_CREATED);
>  
> -    /*
> -     * Note: uses machine properties such as kernel-irqchip, must run
> -     * after qemu_apply_machine_options.
> -     */
>      accel = configure_accelerators(argv[0]);
> -    create_accelerator(accel);
> -    phase_advance(PHASE_ACCEL_CREATED);
>  
>      /*
> -     * Beware, QOM objects created before this point miss global and
> +     * QOM objects created after this point see all global and
>       * compat properties.
>       *
>       * Global properties get set up by qdev_prop_register_global(),
> @@ -3765,6 +3751,22 @@ void qemu_init(int argc, char **argv)
>       * called from do_configure_accelerator().
>       */
>  
> +    suspend_mux_open();
> +
> +    qemu_disable_default_devices();
> +    qemu_setup_display();
> +    qemu_create_default_devices();
> +    qemu_create_early_backends();
> +
> +    phase_advance(PHASE_MACHINE_CREATED);
> +
> +    /*
> +     * Note: uses machine properties such as kernel-irqchip, must run
> +     * after qemu_apply_machine_options.
> +     */
> +    create_accelerator(accel);
> +    phase_advance(PHASE_ACCEL_CREATED);
> +
>      machine_class = MACHINE_GET_CLASS(current_machine);
>      if (!qtest_enabled() && machine_class->deprecation_reason) {
>          warn_report("Machine type '%s' is deprecated: %s",
> -- 
> 1.8.3.1
> 

-- 
Peter Xu