[Qemu-devel] [PATCH v4 0/9] enable numa configuration before machine_init() from QMP

[Igor Mammedov <imammedo@redhat.com>]

v3->v4:
  * replace 'runstates' list in  QMP command with a single
    boolean 'ption allowed-in-preconfig' like it's done with
    'allow-oob'. Which allows to simplify intrusive QAPI
    changes quite a lot. (Eric Blake <eblake@redhat.com>)
  * Make sure HMP is disbled for real, v3 was just printing
    error mesage but allowing command to be executed
    ("Dr. David Alan Gilbert" <dgilbert@redhat.com>)
  * Improve "cli: add -preconfig option" commit message,
    explain a bit more on semantics of new state/option.
  * ithe rest of minor fixups suggested at v3 review
    (Eric Blake <eblake@redhat.com>)
    PS:
       havn't impl. test for new option in
         tests/qapi-schema/qapi-schema-test.json yet,
       can do it on top if approach is acceptable.
v1->v3:
  * introduce PRECONFIG runstate with -preconfig option.
    it's cleaner to manage transitions and do checks
    than reusing existing PRELAUNCH state.
  * extend QAPI schema commands with 'runstates' keyword,
    so that it would be possible to specify in command definition
    when it is valid to execute.
    (python changes a bit hackery, since I have little to
     no idea how it should work)
  * add preconfig QMP and set-numa-node tests
  * make mutually exclusive -preconfig and -incoming options,
    for simplicity sake. Shouldn't be problem as target can
    be starter with pure CLI, since mapping on source is
    already known.
  * Drop HMP part and leave only QMP in preconfig state.


Series allows to configure NUMA mapping at runtime using QMP
interface. For that to happen it introduces a new '-preconfig' CLI option
which allows to pause QEMU before machine_init() is run and
adds new set-numa-node QMP command which in conjunction with
query-hotpluggable-cpus allows to configure NUMA mapping for cpus.

Later we can modify other commands to run early, for example device_add.
I recall SPAPR had problem when libvirt started QEMU with -S and, while it's
paused, added CPUs with device_add. Intent was to coldplug CPUs (but at that
stage it's considered hotplug already), so SPAPR had to work around the issue.

Example of configuration session:
$QEMU -smp 2 -preconfig ...

QMP:
# get CPUs layout for current target/machine/CLI
-> {'execute': 'query-hotpluggable-cpus' }  
<- {'return': [
       {'props': {'core-id': 0, 'thread-id': 0, 'socket-id': 1}, ... },
       {'props': {'core-id': 0, 'thread-id': 0, 'socket-id': 0}, ... }
   ]}

# configure 1st node
-> {'execute': 'set-numa-node', 'arguments': { 'type': 'node', 'nodeid': 0 } }  
<- {'return': {}}
-> {'execute': 'set-numa-node', 'arguments': { 'type': 'cpu',   
       'node-id': 0, 'core-id': 0, 'thread-id': 0, 'socket-id': 1, }
   }
<- {'return': {}}

# configure 2nd node
-> {'execute': 'set-numa-node', 'arguments': { 'type': 'node', 'nodeid': 1 } }
-> {'execute': 'set-numa-node', 'arguments': { 'type': 'cpu',  
       'node-id': 1, 'core-id': 0, 'thread-id': 0, 'socket-id': 0 }
   }
<- {'return': {}}

# [optional] verify configuration
-> {'execute': 'query-hotpluggable-cpus' }  
<- {'return': [
       {'props': {'core-id': 0, 'thread-id': 0, 'node-id': 0, 'socket-id': 1}, ... },
       {'props': {'core-id': 0, 'thread-id': 0, 'node-id': 1, 'socket-id': 0}, ... }
   ]}


Git tree:
    https://github.com/imammedo/qemu.git qmp_preconfig_v3

Ref to v1:
    https://lists.gnu.org/archive/html/qemu-devel/2017-10/msg03583.html
    Message-Id: <1508170976-96869-1-git-send-email-imammedo@redhat.com>
  
CC: eblake@redhat.com
CC: armbru@redhat.com
CC: ehabkost@redhat.com
CC: pkrempa@redhat.com
CC: david@gibson.dropbear.id.au
CC: peter.maydell@linaro.org
CC: pbonzini@redhat.com
CC: cohuck@redhat.com


Igor Mammedov (9):
  numa: postpone options post-processing till machine_run_board_init()
  numa: split out NumaOptions parsing into parse_NumaOptions()
  cli: add -preconfig option
  hmp: disable monitor in preconfig state
  qapi: introduce new cmd option "allowed-in-preconfig"
  tests: extend qmp test with preconfig checks
  qmp: permit query-hotpluggable-cpus in preconfig state
  qmp: add set-numa-node command
  tests: functional tests for QMP command set-numa-node

 include/qapi/qmp/dispatch.h    |  3 +-
 include/sysemu/numa.h          |  2 ++
 include/sysemu/sysemu.h        |  1 +
 tests/libqtest.h               |  9 ++++++
 docs/devel/qapi-code-gen.txt   | 10 ++++++-
 hw/core/machine.c              |  5 ++--
 monitor.c                      | 10 +++++--
 numa.c                         | 66 +++++++++++++++++++++++++++---------------
 qapi/introspect.json           |  6 +++-
 qapi/misc.json                 | 24 ++++++++++++---
 qapi/qmp-dispatch.c            |  8 +++++
 qapi/run-state.json            |  8 +++--
 qemu-options.hx                | 13 +++++++++
 qmp.c                          |  5 ++++
 scripts/qapi/commands.py       | 19 ++++++++----
 scripts/qapi/common.py         | 15 ++++++----
 scripts/qapi/doc.py            |  2 +-
 scripts/qapi/introspect.py     | 10 +++++--
 tests/libqtest.c               |  7 +++++
 tests/numa-test.c              | 61 ++++++++++++++++++++++++++++++++++++++
 tests/qapi-schema/test-qapi.py |  2 +-
 tests/qmp-test.c               | 37 +++++++++++++++++++++++
 vl.c                           | 35 +++++++++++++++++++++-
 23 files changed, 306 insertions(+), 52 deletions(-)

-- 
2.7.4