Re: [libvirt] CPU models and feature probing (was Re: [PATCH qom-cpu 00/16 v10] target-i386: convert CPU) features into properties
Il 07/02/2014 11:16, Eduardo Habkost ha scritto:
You are not alone. I remember we spent lots of time trying to
convince
Anthony to allow global properties and compat_props affect dynamic
properties not just static properties, and static properties were a big
deal due to reasons I didn't understand completely. Now I am hearing the
opposite message, and I don't understand the reasons for the change of
plans. I am confused.
Picture me confused as well, but at the same I think I understand the
reasons for the change of plans.
At some point you have to acknowledge that the grand vision of QEMU as a
small core and management only poking at QOM objects with properties has
never materialized, and probably never will.
After seeing no progress whatsoever on
http://wiki.qemu.org/Features/QOM#TODO after 2 years, we should perhaps
try to get fresh ideas into QOM based on how we've been using it and
what we'd like to do with it. "Design by committee" (more accurately:
"design by prophet") will not lead us anywhere.
QOM definitely needs dynamic properties for child<>, and for tricks such
as simulation of array properties. However, assume Igor or Eduardo or
Marcel can come up with a new QAPI-friendly static properties design,
that combines the best feature of QOM dynamic properties and qdev static
properties, why should it be rejected?
Code should not be frozen against some abstract design, it must evolve
to solve concrete problems until it can solve all of them easily. Or do
we want to become a project where good code is not anymore the best way
to have other developers change their mind?
Paolo