Re: [Qemu-devel] qgraph

[Andreas Färber]

Am 11.06.19 um 12:31 schrieb Paolo Bonzini:
> On 11/06/19 10:56, Markus Armbruster wrote:
>> Yes, this is how introspection (both QMP and QOM) is commonly used.
>> Just keep in mind one difference: QMP is static, QOM is dynamic.
>>
>> QMP being static means it's defined at compile time.  So is the value of
>> query-qmp-schema.  Same QEMU build, same value.  This permits caching.
>>
>> QOM being dynamic means to introspect an object's properties, you have
>> to create it.  Worse, an object's properties may (in theory) change at
>> any time.  *Properties*, not just property *values*.  In practice, I'd
>> expect properties to change only at realize time.
> 
> Right, and we should move more towards class-based properties so that
> the dynamic nature of QOM is only used for the bare minimum needed (e.g.
> memory regions).

I believe it was Paolo who once reminded me that all child<> properties
are dynamic. And link<> properties for bus devices are also dynamic. I
don't see a good way around that.

Regards,
Andreas

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