Re: [PATCH 06/12] hw/ppc: Explicitly create the drc container

[Philippe Mathieu-Daudé]

Hi Peter,

On 20/11/24 22:56, Peter Xu wrote:
> QEMU will start to not rely on implicit creations of containers soon.  Make
> PPC drc devices follow by explicitly create the container whenever a drc
> device is realized, dropping container_get() calls.
>
> No functional change intended.
>
> Cc: Nicholas Piggin <npiggin@gmail.com>
> Cc: Daniel Henrique Barboza <danielhb413@gmail.com>
> Cc: Harsh Prateek Bora <harshpb@linux.ibm.com>
> Cc: qemu-ppc@nongnu.org
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>   hw/ppc/spapr_drc.c | 40 ++++++++++++++++++++++++++++++----------
>   1 file changed, 30 insertions(+), 10 deletions(-)


> +static GOnce drc_container_created = G_ONCE_INIT;
> +
> +static gpointer drc_container_create(gpointer unused G_GNUC_UNUSED)
> +{
> +    container_create(object_get_root(), DRC_CONTAINER_PATH);
> +    return NULL;
> +}
> +
> +static Object *drc_container_get(void)
> +{
> +    return object_resolve_path_component(
> +        object_get_root(), DRC_CONTAINER_PATH);
> +}
> +
> +/* TODO: create the container in an ppc init function */
> +static void drc_container_create_once(void)
> +{
> +    g_once(&drc_container_created, drc_container_create, NULL);
> +}
> +
>   static void drc_realize(DeviceState *d, Error **errp)
>   {
>       SpaprDrc *drc = SPAPR_DR_CONNECTOR(d);
> @@ -521,6 +541,9 @@ static void drc_realize(DeviceState *d, Error **errp)
>       Object *root_container;
>       const char *child_name;
>   
> +    /* Whenever a DRC device is realized, create the container */
> +    drc_container_create_once();

Can't we just create it once in spapr_dr_connector_class_init(),
removing the G_ONCE_INIT need?

>       trace_spapr_drc_realize(spapr_drc_index(drc));
>       /* NOTE: we do this as part of realize/unrealize due to the fact
>        * that the guest will communicate with the DRC via RTAS calls
> @@ -529,7 +552,7 @@ static void drc_realize(DeviceState *d, Error **errp)
>        * inaccessible by the guest, since lookups rely on this path
>        * existing in the composition tree
>        */
> -    root_container = container_get(object_get_root(), DRC_CONTAINER_PATH);
> +    root_container = drc_container_get();
>       child_name = object_get_canonical_path_component(OBJECT(drc));
>       trace_spapr_drc_realize_child(spapr_drc_index(drc), child_name);
>       object_property_add_alias(root_container, link_name,