prebuild cpu QOM tree /machine/node/socket/core ->link-cpu

at present, after hotplug a discontinuous cpu id on source, then done migration, on target, it will fail to add the unoccupied cpu id which was skipped at source, this cause is on target Qemu prebuild CPU with continuous cpu_index. so after migration, the cpu infrastructure bewteen source and target are different.

I suppose we could use apic_id as instance_id which was used at registering vmstate when create cpu. on target, we prebuild the specified cpu topology using comand line:
-device /machine/node[]/socket[]/core[]/cpu[], then migration, we could keep the same
cpu infrastructure on both side.

v1-v2: squash patch 2/4 and 3/4 together.

RFC:
V4: rename CpuTopoInfo to X86CPUTopoInfo. and move cpu_exsit() to pc_new_cpu().

V3: get rid of thread object and tie link<cpu> to <core> directly. and prebuild full
core[] and thread[] as init socket[] according to smp_cores and smp_threads.

TODO:
1. add cpu "path" property which used for specifying the QOM path.
2. add -device cpu-foo.path supported.
3. then we could introduce hot-remove cpu probably.

I don't know wether this way is right or not. pls tell me. :)

Chen Fan (3):
cpu: introduce CpuTopoInfo structure for argument simplification
i386: use CpuTopoInfo instead apic_id as argument for pc_new_cpu()
i386: introduce cpu QOM hierarchy tree

 hw/i386/pc.c               |  25 +++---
 target-i386/Makefile.objs  |   2 +-
 target-i386/cpu-topology.c | 199 +++++++++++++++++++++++++++++++++++++++++++++
 target-i386/cpu-topology.h |  71 ++++++++++++++++
 target-i386/cpu.c          |  55 +++++++++----
 target-i386/cpu.h          |   8 ++
 target-i386/topology.h     |  53 +++++++-----
 tests/test-x86-cpuid.c     | 165 +++++++++++++++++++++++++++++--------
 8 files changed, 494 insertions(+), 84 deletions(-)
 create mode 100644 target-i386/cpu-topology.c
 create mode 100644 target-i386/cpu-topology.h

1.8.1.4