On 3/12/21 10:31 AM, Claudio Fontana wrote:
> Hello Paolo and all,
>
> while debugging a class init ordering issue, I noticed that
>
> _all_ class init functions for all types registered in the QEMU QOM are
> called in select_machine().
> Expected?
>
> In particular it happens here:
>
> static MachineClass *select_machine(void)
> {
> GSList *machines = object_class_get_list(TYPE_MACHINE, false);
>
>
> object_class_get_list() ->
> object_class_foreach() ->
> g_hash_table_foreach() ->
> object_class_foreach_tramp ->
> type_initialize(type);
>
>
> Is this really desired? It looks suspect to me.
>
> (gdb) bt
> #0 0x0000555555db613f in arm_v7m_class_init (oc=0x555556dca320,
> data=0x555556a926e0 <arm_tcg_cpus+288>)
> at ../target/arm/tcg/tcg-cpu-models.c:849
> #1 0x0000555555f1deba in type_initialize (ti=0x555556d5b2f0) at
> ../qom/object.c:364
> #2 0x0000555555f1f62a in object_class_foreach_tramp (key=0x555556d5b470,
> value=0x555556d5b2f0, opaque=0x7fffffffda20)
> at ../qom/object.c:1069
> #3 0x00007ffff6562000 in g_hash_table_foreach () at
> /usr/lib64/libglib-2.0.so.0
> #4 0x0000555555f1f709 in object_class_foreach (fn=
> 0x555555f1f866 <object_class_get_list_tramp>,
> implements_type=0x555556381b09 "machine", include_abstract=false,
> opaque=0x7fffffffda70)
> at ../qom/object.c:1091
> #5 0x0000555555f1f8e4 in object_class_get_list
> (implements_type=0x555556381b09 "machine", include_abstract=false) at
> ../qom/object.c:1148
> #6 0x0000555555debe94 in select_machine () at ../softmmu/vl.c:1607
>
>
> If not here, where should be the right place, for example, for CPU class
> inits to be called?
>
> At the very least I would put a comment there around the beginning of
> select_machine() saying:
>
> /* all types, all classes in QOM are initialized here, as a result of the
> object_class_get_list call */
>
> Wdyt?
Are you trying to register types conditionally?
