Re: [Qemu-devel] [PATCH v3 3/7] qom: create objects in two phases

["Andreas Färber" <afaerber@suse.de>]

Hi,

Can we *please* find a better subject for this? To me, creating QOM
objects in two phases is about instance_init vs. realize, and thus I was
pretty upset that Paolo dared to apply this without asking me first.

Am 01.05.2015 um 12:30 schrieb Daniel P. Berrange:
> Some types of object must be created before chardevs, other types of
> object must be created after chardevs. As such there is no option but
> to create objects in two phases.
> 
> This takes the decision to create as many object types as possible
> in the first phase, and only delay those which have a dependency on
> the chardevs. Hopefully the set which need delaying will remain
> small.
> 
> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
> ---
>  vl.c | 40 +++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 39 insertions(+), 1 deletion(-)
> 
> diff --git a/vl.c b/vl.c
> index 74c2681..ee2f70a 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -2591,6 +2591,33 @@ static int machine_set_property(const char *name, const char *value,
>      return 0;
>  }
>  
> +
> +/**

Accidental documentation comment?

> + * Initial object creation happens before all other
> + * QEMU data types are created. The majority of objects
> + * can be created at this point. The rng-egd object
> + * cannot be created here, as it depends on the chardev
> + * already existing.
> + */
> +static bool object_create_initial(const char *type)
> +{
> +    if (g_str_equal(type, "rng-egd")) {
> +        return false;
> +    }
> +    return true;
> +}
> +
> +
> +/**

Ditto?

> + * The remainder of object creation happens after the
> + * creation of chardev, fsdev and device data types.
> + */
> +static bool object_create_delayed(const char *type)
> +{
> +    return !object_create_initial(type);
> +}
> +
> +
>  static int object_create(QemuOpts *opts, void *opaque)
>  {
>      Error *err = NULL;
> @@ -2599,6 +2626,7 @@ static int object_create(QemuOpts *opts, void *opaque)
>      void *dummy = NULL;
>      OptsVisitor *ov;
>      QDict *pdict;
> +    bool (*type_predicate)(const char *) = opaque;
>  
>      ov = opts_visitor_new(opts);
>      pdict = qemu_opts_to_qdict(opts, NULL);
> @@ -2613,6 +2641,9 @@ static int object_create(QemuOpts *opts, void *opaque)
>      if (err) {
>          goto out;
>      }
> +    if (!type_predicate(type)) {
> +        goto out;
> +    }
>  
>      qdict_del(pdict, "id");
>      visit_type_str(opts_get_visitor(ov), &id, "id", &err);
> @@ -4008,6 +4039,12 @@ int main(int argc, char **argv, char **envp)
>  
>      socket_init();
>  
> +    if (qemu_opts_foreach(qemu_find_opts("object"),
> +                          object_create,
> +                          object_create_initial, 0) != 0) {
> +        exit(1);
> +    }
> +
>      if (qemu_opts_foreach(qemu_find_opts("chardev"), chardev_init_func, NULL, 1) != 0)
>          exit(1);
>  #ifdef CONFIG_VIRTFS
> @@ -4027,7 +4064,8 @@ int main(int argc, char **argv, char **envp)
>      }
>  
>      if (qemu_opts_foreach(qemu_find_opts("object"),
> -                          object_create, NULL, 0) != 0) {
> +                          object_create,
> +                          object_create_delayed, 0) != 0) {
>          exit(1);
>      }
>  

Otherwise looks okay and there's a pattern emerging of "not qom:".

Regards,
Andreas

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