[PULL 31/39] migration: Improve example and documentation of vmstate_register()

Reviewed-by: Stefan Berger <stefanb(a)linux.ibm.com&gt; Signed-off-by: Juan Quintela <quintela(a)redhat.com&gt; Message-ID: <20231020090731.28701-11-quintela(a)redhat.com&gt; --- docs/devel/migration.rst | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst index be913630c3..240eb16d90 100644 --- a/docs/devel/migration.rst +++ b/docs/devel/migration.rst @@ -167,13 +167,17 @@ An example (from hw/input/pckbd.c) } }; -We are declaring the state with name "pckbd". -The ``version_id`` is 3, and the fields are 4 uint8_t in a KBDState structure. -We registered this with: +We are declaring the state with name "pckbd". The ``version_id`` is +3, and there are 4 uint8_t fields in the KBDState structure. We +registered this ``VMSTATEDescription`` with one of the following +functions. The first one will generate a device ``instance_id`` +different for each registration. Use the second one if you already +have an id that is different for each instance of the device: .. code:: c - vmstate_register(NULL, 0, &vmstate_kbd, s); + vmstate_register_any(NULL, &vmstate_kbd, s); + vmstate_register(NULL, instance_id, &vmstate_kbd, s); For devices that are ``qdev`` based, we can register the device in the class init function: -- 2.41.0