Re: [Qemu-devel] [PATCH 4/4] xics: Support for in-kernel XICS interrupt controller

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 08/01/2013 11:29 AM, Andreas Färber wrote:
> Am 01.08.2013 02:14, schrieb Alexey Kardashevskiy:
>> On 08/01/2013 05:52 AM, Andreas Färber wrote:
>>> Am 17.07.2013 08:37, schrieb Alexey Kardashevskiy:

>>>> +
>>>> +    icp->ss = g_malloc0(icp->nr_servers*sizeof(ICPState));
>>>> +    for (i = 0; i < icp->nr_servers; i++) {
>>>> +        char buffer[32];
>>>> +        object_initialize(&icp->ss[i], TYPE_ICP_KVM);
>>>> +        snprintf(buffer, sizeof(buffer), "icp[%d]", i);
>>>> +        object_property_add_child(OBJECT(icp), buffer, OBJECT(&icp->ss[i]), NULL);
>>>> +        qdev_init_nofail(DEVICE(&icp->ss[i]));
>>>
>>> object_property_set_bool()
>>
>>
>> ? Anthony did XICS refactoring recently and that has qdev_init_nofail().
> 
> Nobody is perfect. ;)
> 
> The point is, this is an object, and in realize you shouldn't abort but
> set errp and leave error printing and handling to your caller. The QOM
> API as opposed to qdev works with an Error object that you can
> error_propagate() to your caller.
> 
> (Also using qdev_* for something that is new-style QOM is ugly IMO.)
> 
>>> Where does icp->nr_servers come from?
>>
>> Via properties in try_create_xics() (hw/ppc/spapr.c).
> 
> Sounds tricky... Peter introduced static array properties for a similar
> purpose, I believe. Don't know if that would help here.

Peter who? For what purpose? Could you please point to it? Cannot find it
anywhere.


>>
>>> Is there no way to split this into
>>> instance_init and realize?
>>
>>
>> Why would we want to split?
> 
> Because realize is too late to create new devices: With our targetted
> late, recursive realization model it will not be possible to see and
> modify such objects from management interface - only before realize.


Oh. I lost you here. I need to create XICS with some child ICP devices (now
they are devices). The number of child devices comes from spapr.c via
properties. Now you are saying it is too late to create devices (even so
lame ones) in realize(). So I have to put the creation in instance_init().
Could you please point now I can create device-and-pass-propetries in one
shot? Thanks!


-- 
Alexey