[Qemu-devel] [RFC PATCH 00/14] Common base for memory hotplug and NUMA policy work

[Paolo Bonzini]

Hi,

this is a proposal for a common tree for memory hotplug and NUMA
policy patches.

The common base for these tree is Igor's "memory device" QOM hierarchy,
that subsumes and improves on the "-numa mem" concept that I had proposed.
These patches include a basic conversion of his QOM hierarchy to -object.
Stefan and Igor are looking at improving -object, but this is not required
to build on this series.

Thanks to the memory device object, NUMA nodes' memory allocation
be expressed easily via a new suboption "-numa node,memdev=ID".
For example:

  -object memory-ram,size=1024M,id=ram-node0 \
  -numa node,nodeid=0,cpus=0,memdev=ram-node0 \
  -object memory-ram,size=1024M,id=ram-node1 \
  -numa node,nodeid=1,cpus=1,memdev=ram-node1 \
  -m 2048

memdev=ID is alternative to mem=SIZE: if you use memdev for one node,
you must use it for all of them.  When memdev is in use, the single
large RAM memory region is replaced by a container region, with all
memdevs layed out one after another.

The integration between boards and the NUMA subsystem is done by
a new function in numa.c, memory_region_allocate_system_memory.
Thus, boards have to request NUMA-aware allocation explicitly.
This however is not a change compared to Wanlong's patches: both
the early ones that hardcoded the "pc.ram" memory region name,
and the latest version that similarly introduced a function for
boards to call (memory_region_set_mem_policy in his patches).

Wanlong can then proceed to add policy properties (hostnode, policy)
to backends/hostmem-ram.c, and these will be automatically applicable
to hotpluggable memory as well.

I'm quite happy with the design of both series.  It took quite a long
time, but it shows the power of the host/guest separation that is
already present in -blockdev/-chardev/-netdev.

You can find this at refs/heads/numa in my github repository, where
I included also the monitor object-add/object-del patches.

Paolo

Igor Mammedov (3):
  qapi: add SIZE type parser to string_input_visitor
  vl: convert -m to QemuOpts
  add memdev backend infrastructure

Paolo Bonzini (6):
  QemuOpts: introduce qemu_find_opts_singleton
  qom: fix leak for objects created with -object
  qom: catch errors in object_property_add_child
  pc: pass QEMUMachineInitArgs to pc_memory_init
  numa: introduce memory_region_allocate_system_memory
  numa: add -numa node,memdev= option

Wanlong Gao (5):
  NUMA: move numa related code to new file numa.c
  NUMA: check if the total numa memory size is equal to ram_size
  NUMA: Add numa_info structure to contain numa nodes info
  NUMA: convert -numa option to use OptsVisitor
  NUMA: expand MAX_NODES from 64 to 128

 Makefile.target             |   2 +-
 backends/Makefile.objs      |   2 +
 backends/hostmem-ram.c      |  46 ++++++++
 backends/hostmem.c          | 116 ++++++++++++++++++++
 cpus.c                      |  14 ---
 hw/i386/pc.c                |  27 ++---
 hw/i386/pc_piix.c           |   8 +-
 hw/i386/pc_q35.c            |   4 +-
 include/hw/i386/pc.h        |   7 +-
 include/qemu/config-file.h  |   2 +
 include/sysemu/cpus.h       |   1 -
 include/sysemu/hostmem.h    |  63 +++++++++++
 include/sysemu/sysemu.h     |  21 +++-
 monitor.c                   |   2 +-
 numa.c                      | 259 ++++++++++++++++++++++++++++++++++++++++++++
 qapi-schema.json            |  34 ++++++
 qapi/string-input-visitor.c |  18 +++
 qemu-options.hx             |   7 +-
 qom/object.c                |   9 +-
 util/qemu-config.c          |  14 +++
 vl.c                        | 221 ++++++++++---------------------------
 21 files changed, 664 insertions(+), 213 deletions(-)
 create mode 100644 backends/hostmem-ram.c
 create mode 100644 backends/hostmem.c
 create mode 100644 include/sysemu/hostmem.h
 create mode 100644 numa.c

-- 
1.8.4.2