Re: [PATCH 10/13] migration: Improve example and documentation of vmstate_register()

[Stefan Berger]

On 10/19/23 15:08, Juan Quintela wrote:
> Signed-off-by: Juan Quintela <quintela@redhat.com>
> ---
>   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 c3e1400c0c..a9fde75862 100644
> --- a/docs/devel/migration.rst
> +++ b/docs/devel/migration.rst
> @@ -165,13 +165,17 @@ 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 the fields are 4 uint8_t in a KBDState structure.  We

and there are 4  uint8_t fields in the KBDState structure.


> +registered this with one of those.  The first one will generate a

I am not sure what this means 'We registered this with one of those'. 
What is 'one of those'?

Maybe you mean: We register the KBDState with one of the following 
functions.

> +device ``instance_id`` different for each registration.  Use the
> +second one if you already have an id different for each instance of
> +the device:
... have an id that is is different for each ...
>   .. 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: