Re: [Qemu-devel] [PATCH qom-cpu 00/15 v8] target-i386: convert CPU features into properties, part 1

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 05 Jun 2013 15:29:08 +0200
Andreas Färber <afaerber@suse.de> wrote:

> Am 05.06.2013 15:18, schrieb Igor Mammedov:
> > It's a rebase of v7 on current qom-cpu tree, since then some patches from it
> > were applied to master. Convertion of feature bits is left for part 2
> > since it's not ready yet.
> > 
> > v7-v8:
> > * split out dynamic properties convertion patch into per property patches
> >   to simplify review
> > * drop feature bits convertion
> 
> Why is conversion of dynamic properties to static properties still
> needed after I applied a solution to override values of dynamic
> properties with -global for 1.5?
Do you mean qdev_prop_set_globals_for_type() & co?
If yes, then I recall it was acceptable hack to permit more clean
approach for compat props fixes to work. And we promised Anthony to
get rid of it when possible.

Now more to the point,

1. if CPU are to be created with device_add(wich is still  a goal)
   cpu_x86_create() won't be created, so it leaves rules out compat
   properties set by qdev_prop_set_globals_for_type().
   Having properties converted by this series as static would open
   road for:
       - making cpu_x86_parse_featurestr() target specific hook that
         deals with legacy cpu_model parsing and converts provided
         features into global properties.
           as result during hot-add device_add can work without
           specifying +-foo1,foo2,level=XXX, it will be applied from
           globals.
       - above will allow to replace create_x86_cpu() with plain
         device_add when subclasses are implemented.

2. I'd like to utilize default values of static properties for defining
   subclasses like here: https://github.com/imammedo/qemu/commit/a48e252a2800bf8dd56320e68e4f9517d0a25e5c
   - that would automatically provide benefit of class introspection
     without creating CPU instance
   - replace current CPU definitions array to a set of class_init_xxx
     for each subclass.

> 
> For HyperV no doubt that the current state needs cleanups.
> 
> Andreas
> 
> > 
> > v6-v7:
> > * convert globals check_cpuid, enforce_cpuid and  hyperv_* to fields of
> >   CPUState
> > * Make PropertyInfo-s static
> > * maintain legacy kvmclock semantic in cpu_x86_parse_featurestr()
> > * existing properties code are not moved around, just fixed signatures where
> >   it's needed and used visitors. 
> > 
> > v5-v6:
> > * when converting feature names to property names, replace '_' with '-'
> > * separate patches converting existing dynamic properties into one, were
> >   squashed into one [1/9] and change tested with virt-test(next).
> > * patches that were touching +-foo features are squashed into one [9/9],
> >   to avoid behavior change between them(f-kvmclock property).
> > * the rest of conversions were basicaly rebased on top of current qom-cpu-next
> >   tree, with small corrections
> > 
> > git for testing: https://github.com/imammedo/qemu/tree/x86-cpu-properties.v8
> > 
> > Igor Mammedov (15):
> >   target-i386: cpu: convert 'family' to static property
> >   target-i386: cpu: convert 'model' to static property
> >   target-i386: cpu: convert 'stepping' to static property
> >   target-i386: cpu: convert 'level' to static property
> >   target-i386: cpu: convert 'xlevel' to static property
> >   target-i386: cpu: convert 'vendor' to static property
> >   target-i386: cpu: convert 'model-id' to static property
> >   target-i386: cpu: convert 'tsc-frequency' to static property
> >   target-i386: move hyperv_* static globals to CPUState
> >   target-i386: convert 'hv_spinlocks' to static property
> >   target-i386: convert 'hv_relaxed' to static property
> >   target-i386: convert 'hv_vapic' to static property
> >   target-i386: convert 'check' and 'enforce' to static properties
> >   target-i386: cleanup 'foo' feature handling'
> >   target-i386: cleanup 'foo=val' feature handling
> > 
> >  target-i386/Makefile.objs |    2 +-
> >  target-i386/cpu.c         |  250 +++++++++++++++++++++++++++------------------
> >  target-i386/cpu.h         |    9 ++
> >  target-i386/hyperv.c      |   64 ------------
> >  target-i386/hyperv.h      |   45 --------
> >  target-i386/kvm.c         |   36 +++++--
> >  6 files changed, 188 insertions(+), 218 deletions(-)
> >  delete mode 100644 target-i386/hyperv.c
> >  delete mode 100644 target-i386/hyperv.h
> > 
> 
>