[Qemu-devel] [PATCH v4 0/2] spapr: QMP: add query-hotpluggable-cpus

[Qemu-devel] [PATCH v4 0/2] spapr: QMP: add query-hotpluggable-cpus

[Igor Mammedov]

Changes since v3:
 - replace qmp_query_hotpluggable_cpus with MachineClass->query_hotpluggable_cpus
   callback. (Eduardo Habkost <ehabkost@redhat.com>)
 - fix cover letter to explain why new command is needed.
   (Markus Armbruster <armbru@redhat.com>)
Changes since v2:
 - rebase on top of hte lates spapr cpu hotpug series
 - add 'vcpus-count' field, pkrempa@redhat.com
 - s/CpuInstanceProps/CpuInstanceProperties/
 - use '#optional' marker
 - make "props" as always present even if it's empty
 - fix JSON examples
 - fix minor typos
 - drop pre_plug spapr impl out of series as not related to QMP command
 - drop generic pre hotplug callback as not related to QMP command

Changes since RFC:
 - drop arch_id
 - move CPU properties into separate structure
 - target implements its own qmp callback version
 - rebased on top of [RFC PATCH v1 00/10] Core based CPU hotplug for PowerPC sPAPR
                      https://www.mail-archive.com/qemu-devel@nongnu.org/msg357567.html
    - convert slot name to core id hack
    - drop links
    - add generic pre hotplug callback
    - implement query-hotpluggable-cpus

Series adds query-hotpluggable-cpus QMP command to allow mgmt
query board specific configuration of possible CPU objects
with their properties, which is target specific and also
depends on CLI options (like -smp/-cpu/-numa).
Returned information includes QOM type of CPU objects and
a set of properties that are necessary for hotplugging them.
Information will be used with device_add/-device when
hotplugging a CPU and migrating QEMU instance with hotplugged CPUs.

PS:
The first patch (QMP API) in this series could go in first
allowing individual targets to post their hotplug
implementation independently on top of it.

PS2:
Summary on QMP vs QOM interface discussion:

a QMP command is
 1. a single / atomic command 
 2. well documented
 3. fixed at compile time/staic so it's easy for mgmt to discover it.

while a considered alternative QOM interface via qom-get(path) is
 1. not atomic, i.e. requires a lot of qom-get requests over the wire
    to traverse QOM tree and fetch information
 2. not documented
 3. dynamically generated and would require more complicated coding
    even to create a simplistic interface similar to proposed QMP command
    (for example: possible_cpu QOM objects with a related properties)


Igor Mammedov (2):
  QMP: add query-hotpluggable-cpus
  spapr: implement query-hotpluggable-cpus callback

 hw/ppc/spapr.c      | 33 +++++++++++++++++++++++++++++++++
 include/hw/boards.h |  5 +++++
 monitor.c           | 13 +++++++++++++
 qapi-schema.json    | 41 +++++++++++++++++++++++++++++++++++++++++
 qmp-commands.hx     | 43 +++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 135 insertions(+)

-- 
1.8.3.1

[Qemu-devel] [PATCH v4 1/2] QMP: add query-hotpluggable-cpus

[Igor Mammedov]

it will allow mgmt to query present and hotpluggable
CPU objects, it is required from a target platform that
wish to support command to implement and set
 MachineClass.query_hotpluggable_cpus
callback, which will return a list of possible CPU objects
with options that would be needed for hotplugging possible
CPU objects.

There are:
'type': 'str' - QOM CPU object type for usage with device_add
'vcpus-count': 'int' - number of logical VCPU threads per
                        CPU object (mgmt needs to know)

and a set of optional fields that are to used for hotplugging
a CPU objects and would allows mgmt tools to know what/where
it could be hotplugged;
[node],[socket],[core],[thread]

For present CPUs there is a 'qom-path' field which
would allow mgmt to inspect whatever object/abstraction
the target platform considers as CPU object.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
v4:
 - add MachineClass method to get CPU object list
v3:
 - add 'vcpus-count' field, pkrempa@redhat.com
 - s/CpuInstanceProps/CpuInstanceProperties/
 - use '#optional' marker
 - make "props" as always present even if it's empty
 - fix JSON examples
 - fix minor typos
---
 include/hw/boards.h |  5 +++++
 monitor.c           | 13 +++++++++++++
 qapi-schema.json    | 41 +++++++++++++++++++++++++++++++++++++++++
 qmp-commands.hx     | 43 +++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 102 insertions(+)

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 8efce0f..a8f7dba 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -82,6 +82,10 @@ typedef struct {
  *    Returns an array of @CPUArchId architecture-dependent CPU IDs
  *    which includes CPU IDs for present and possible to hotplug CPUs.
  *    Caller is responsible for freeing returned list.
+ * @query_hotpluggable_cpus:
+ *    Returns a @HotpluggableCPUList, which describes CPUs objects which
+ *    could be added with -device/device_add.
+ *    Caller is responsible for freeing returned list.
  */
 struct MachineClass {
     /*< private >*/
@@ -124,6 +128,7 @@ struct MachineClass {
                                            DeviceState *dev);
     unsigned (*cpu_index_to_socket_id)(unsigned cpu_index);
     CPUArchIdList *(*possible_cpu_arch_ids)(MachineState *machine);
+    HotpluggableCPUList *(*query_hotpluggable_cpus)(MachineState *machine);
 };
 
 /**
diff --git a/monitor.c b/monitor.c
index 4c02f0f..490e214 100644
--- a/monitor.c
+++ b/monitor.c
@@ -4257,4 +4257,17 @@ void qmp_dump_skeys(const char *filename, Error **errp)
 {
     error_setg(errp, QERR_FEATURE_DISABLED, "dump-skeys");
 }
+
+HotpluggableCPUList *qmp_query_hotpluggable_cpus(Error **errp)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+    MachineClass *mc = MACHINE_GET_CLASS(ms);
+
+    if (!mc->query_hotpluggable_cpus) {
+        error_setg(errp, QERR_FEATURE_DISABLED, "query-hotpluggable-cpus");
+        return NULL;
+    }
+
+    return mc->query_hotpluggable_cpus(ms);
+}
 #endif
diff --git a/qapi-schema.json b/qapi-schema.json
index 88f9b81..71e20e1 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -4126,3 +4126,44 @@
 ##
 { 'enum': 'ReplayMode',
   'data': [ 'none', 'record', 'play' ] }
+
+##
+# CpuInstanceProperties
+#
+# @node: NUMA node ID the CPU belongs to, optional
+# @socket: #optional socket number within node/board the CPU belongs to
+# @core: #optional core number within socket the CPU belongs to
+# @thread: #optional thread number within core the CPU belongs to
+#
+# Since: 2.7
+{ 'struct': 'CpuInstanceProperties',
+  'data': { '*node': 'int',
+            '*socket': 'int',
+            '*core': 'int',
+            '*thread': 'int'
+  }
+}
+
+##
+# @HotpluggableCPU
+#
+# @type: CPU object type for usage with device_add command
+# @props: list of properties to be used for hotplugging CPU
+# @vcpus-count: number of logical VCPU threads @HotpluggableCPU provides
+# @qom-path: #optional link to existing CPU object if CPU is present or
+#            omitted if CPU is not present.
+#
+# Since: 2.7
+{ 'struct': 'HotpluggableCPU',
+  'data': { 'type': 'str',
+            'vcpus-count': 'int',
+            'props': 'CpuInstanceProperties',
+            '*qom-path': 'str'
+          }
+}
+
+##
+# @query-hotpluggable-cpus
+#
+# Since: 2.7
+{ 'command': 'query-hotpluggable-cpus', 'returns': ['HotpluggableCPU'] }
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 9e05365..85ffba3 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -4853,3 +4853,46 @@ Example:
                  {"type": 0, "out-pport": 0, "pport": 0, "vlan-id": 3840,
                   "pop-vlan": 1, "id": 251658240}
    ]}
+
+EQMP
+
+    {
+        .name       = "query-hotpluggable-cpus",
+        .args_type  = "",
+        .mhandler.cmd_new = qmp_marshal_query_hotpluggable_cpus,
+    },
+
+SQMP
+Show  existing/possible CPUs
+-------------------------------
+
+Arguments: None.
+
+Example for x86 target started with -smp 2,sockets=2,cores=1,threads=3,maxcpus=6:
+
+-> { "execute": "query-hotpluggable-cpus" }
+<- {"return": [
+     { "props": { "core": 0, "socket": 1, "thread": 2},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 1, "thread": 1},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 1, "thread": 0},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 0, "thread": 2},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 0, "thread": 1},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1,
+       "qom-path": "/machine/unattached/device[3]"},
+     { "props": { "core": 0, "socket": 0, "thread": 0},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1,
+       "qom-path": "/machine/unattached/device[0]"}
+   ]}'
+
+Example for SPAPR target started with -smp 2,cores=2,maxcpus=4:
+
+-> { "execute": "query-hotpluggable-cpus" }
+<- {"return": [
+     { "props": { "core": 1 }, "type": "spapr-cpu-core", "vcpus-count": 1 },
+     { "props": { "core": 0 }, "type": "spapr-cpu-core", "vcpus-count": 1,
+       "qom-path": "/machine/unattached/device[0]"}
+   ]}'
-- 
1.8.3.1

[Qemu-devel] [PATCH v5 1/2] QMP: add query-hotpluggable-cpus

[Igor Mammedov]

it will allow mgmt to query present and hotpluggable
CPU objects, it is required from a target platform that
wish to support command to implement and set
 MachineClass.query_hotpluggable_cpus
callback, which will return a list of possible CPU objects
with options that would be needed for hotplugging possible
CPU objects.

There are:
'type': 'str' - QOM CPU object type for usage with device_add
'vcpus-count': 'int' - number of logical VCPU threads per
                        CPU object (mgmt needs to know)

and a set of optional fields that are to used for hotplugging
a CPU objects and would allows mgmt tools to know what/where
it could be hotplugged;
[node],[socket],[core],[thread]

For present CPUs there is a 'qom-path' field which
would allow mgmt to inspect whatever object/abstraction
the target platform considers as CPU object.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
v5:
 - fix s390 build failure:
    undefined reference to `qmp_query_hotpluggable_cpus'
v4:
 - add MachineClass method to get CPU object list
v3:
 - add 'vcpus-count' field, pkrempa@redhat.com
 - s/CpuInstanceProps/CpuInstanceProperties/
 - use '#optional' marker
 - make "props" as always present even if it's empty
 - fix JSON examples
 - fix minor typos
---
 include/hw/boards.h |  5 +++++
 monitor.c           | 13 +++++++++++++
 qapi-schema.json    | 41 +++++++++++++++++++++++++++++++++++++++++
 qmp-commands.hx     | 43 +++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 102 insertions(+)

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 8efce0f..a8f7dba 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -82,6 +82,10 @@ typedef struct {
  *    Returns an array of @CPUArchId architecture-dependent CPU IDs
  *    which includes CPU IDs for present and possible to hotplug CPUs.
  *    Caller is responsible for freeing returned list.
+ * @query_hotpluggable_cpus:
+ *    Returns a @HotpluggableCPUList, which describes CPUs objects which
+ *    could be added with -device/device_add.
+ *    Caller is responsible for freeing returned list.
  */
 struct MachineClass {
     /*< private >*/
@@ -124,6 +128,7 @@ struct MachineClass {
                                            DeviceState *dev);
     unsigned (*cpu_index_to_socket_id)(unsigned cpu_index);
     CPUArchIdList *(*possible_cpu_arch_ids)(MachineState *machine);
+    HotpluggableCPUList *(*query_hotpluggable_cpus)(MachineState *machine);
 };
 
 /**
diff --git a/monitor.c b/monitor.c
index 4c02f0f..876dde4 100644
--- a/monitor.c
+++ b/monitor.c
@@ -4258,3 +4258,16 @@ void qmp_dump_skeys(const char *filename, Error **errp)
     error_setg(errp, QERR_FEATURE_DISABLED, "dump-skeys");
 }
 #endif
+
+HotpluggableCPUList *qmp_query_hotpluggable_cpus(Error **errp)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+    MachineClass *mc = MACHINE_GET_CLASS(ms);
+
+    if (!mc->query_hotpluggable_cpus) {
+        error_setg(errp, QERR_FEATURE_DISABLED, "query-hotpluggable-cpus");
+        return NULL;
+    }
+
+    return mc->query_hotpluggable_cpus(ms);
+}
diff --git a/qapi-schema.json b/qapi-schema.json
index 88f9b81..71e20e1 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -4126,3 +4126,44 @@
 ##
 { 'enum': 'ReplayMode',
   'data': [ 'none', 'record', 'play' ] }
+
+##
+# CpuInstanceProperties
+#
+# @node: NUMA node ID the CPU belongs to, optional
+# @socket: #optional socket number within node/board the CPU belongs to
+# @core: #optional core number within socket the CPU belongs to
+# @thread: #optional thread number within core the CPU belongs to
+#
+# Since: 2.7
+{ 'struct': 'CpuInstanceProperties',
+  'data': { '*node': 'int',
+            '*socket': 'int',
+            '*core': 'int',
+            '*thread': 'int'
+  }
+}
+
+##
+# @HotpluggableCPU
+#
+# @type: CPU object type for usage with device_add command
+# @props: list of properties to be used for hotplugging CPU
+# @vcpus-count: number of logical VCPU threads @HotpluggableCPU provides
+# @qom-path: #optional link to existing CPU object if CPU is present or
+#            omitted if CPU is not present.
+#
+# Since: 2.7
+{ 'struct': 'HotpluggableCPU',
+  'data': { 'type': 'str',
+            'vcpus-count': 'int',
+            'props': 'CpuInstanceProperties',
+            '*qom-path': 'str'
+          }
+}
+
+##
+# @query-hotpluggable-cpus
+#
+# Since: 2.7
+{ 'command': 'query-hotpluggable-cpus', 'returns': ['HotpluggableCPU'] }
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 9e05365..85ffba3 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -4853,3 +4853,46 @@ Example:
                  {"type": 0, "out-pport": 0, "pport": 0, "vlan-id": 3840,
                   "pop-vlan": 1, "id": 251658240}
    ]}
+
+EQMP
+
+    {
+        .name       = "query-hotpluggable-cpus",
+        .args_type  = "",
+        .mhandler.cmd_new = qmp_marshal_query_hotpluggable_cpus,
+    },
+
+SQMP
+Show  existing/possible CPUs
+-------------------------------
+
+Arguments: None.
+
+Example for x86 target started with -smp 2,sockets=2,cores=1,threads=3,maxcpus=6:
+
+-> { "execute": "query-hotpluggable-cpus" }
+<- {"return": [
+     { "props": { "core": 0, "socket": 1, "thread": 2},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 1, "thread": 1},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 1, "thread": 0},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 0, "thread": 2},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1 },
+     { "props": { "core": 0, "socket": 0, "thread": 1},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1,
+       "qom-path": "/machine/unattached/device[3]"},
+     { "props": { "core": 0, "socket": 0, "thread": 0},
+       "type": "qemu64-x86_64-cpu", "vcpus-count": 1,
+       "qom-path": "/machine/unattached/device[0]"}
+   ]}'
+
+Example for SPAPR target started with -smp 2,cores=2,maxcpus=4:
+
+-> { "execute": "query-hotpluggable-cpus" }
+<- {"return": [
+     { "props": { "core": 1 }, "type": "spapr-cpu-core", "vcpus-count": 1 },
+     { "props": { "core": 0 }, "type": "spapr-cpu-core", "vcpus-count": 1,
+       "qom-path": "/machine/unattached/device[0]"}
+   ]}'
-- 
1.8.3.1

Re: [Qemu-devel] [PATCH v5 1/2] QMP: add query-hotpluggable-cpus

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 3403 bytes --]

On 03/26/2016 12:56 PM, Igor Mammedov wrote:
> it will allow mgmt to query present and hotpluggable
> CPU objects, it is required from a target platform that
> wish to support command to implement and set
>  MachineClass.query_hotpluggable_cpus
> callback, which will return a list of possible CPU objects
> with options that would be needed for hotplugging possible
> CPU objects.
> 
> There are:
> 'type': 'str' - QOM CPU object type for usage with device_add
> 'vcpus-count': 'int' - number of logical VCPU threads per
>                         CPU object (mgmt needs to know)
> 
> and a set of optional fields that are to used for hotplugging
> a CPU objects and would allows mgmt tools to know what/where
> it could be hotplugged;
> [node],[socket],[core],[thread]
> 
> For present CPUs there is a 'qom-path' field which
> would allow mgmt to inspect whatever object/abstraction
> the target platform considers as CPU object.
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---

> +++ b/qapi-schema.json
> @@ -4126,3 +4126,44 @@
>  ##
>  { 'enum': 'ReplayMode',
>    'data': [ 'none', 'record', 'play' ] }
> +
> +##
> +# CpuInstanceProperties
> +#
> +# @node: NUMA node ID the CPU belongs to, optional

Mark this with '#optional', like you do in the other members.

> +# @socket: #optional socket number within node/board the CPU belongs to
> +# @core: #optional core number within socket the CPU belongs to
> +# @thread: #optional thread number within core the CPU belongs to
> +#
> +# Since: 2.7
> +{ 'struct': 'CpuInstanceProperties',

Missing ## trailing doc marker.  Doesn't matter quite yet, but will once
Marc-Andre's patches for automated doc generation land.

> +  'data': { '*node': 'int',
> +            '*socket': 'int',
> +            '*core': 'int',
> +            '*thread': 'int'
> +  }
> +}
> +
> +##
> +# @HotpluggableCPU
> +#
> +# @type: CPU object type for usage with device_add command
> +# @props: list of properties to be used for hotplugging CPU
> +# @vcpus-count: number of logical VCPU threads @HotpluggableCPU provides
> +# @qom-path: #optional link to existing CPU object if CPU is present or
> +#            omitted if CPU is not present.
> +#
> +# Since: 2.7
> +{ 'struct': 'HotpluggableCPU',

Another missing ##

> +  'data': { 'type': 'str',
> +            'vcpus-count': 'int',
> +            'props': 'CpuInstanceProperties',
> +            '*qom-path': 'str'
> +          }
> +}
> +
> +##
> +# @query-hotpluggable-cpus
> +#
> +# Since: 2.7
> +{ 'command': 'query-hotpluggable-cpus', 'returns': ['HotpluggableCPU'] }

Looks okay.

> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index 9e05365..85ffba3 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -4853,3 +4853,46 @@ Example:
>                   {"type": 0, "out-pport": 0, "pport": 0, "vlan-id": 3840,
>                    "pop-vlan": 1, "id": 251658240}
>     ]}
> +
> +EQMP
> +
> +    {
> +        .name       = "query-hotpluggable-cpus",
> +        .args_type  = "",
> +        .mhandler.cmd_new = qmp_marshal_query_hotpluggable_cpus,
> +    },
> +
> +SQMP
> +Show  existing/possible CPUs

Why two spaces?

> +-------------------------------

Line is too long.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


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[Qemu-devel] [RFC v4 2/2] spapr: implement query-hotpluggable-cpus callback

[Igor Mammedov]

it returns a list of present/possible to hotplug CPU
objects with a list of properties to use with
device_add.

in spapr case returned list would looks like:
-> { "execute": "query-hotpluggable-cpus" }
<- {"return": [
     { "props": { "core": 1 }, "type": "spapr-cpu-core",
       "vcpus-count": 2 },
     { "props": { "core": 0 }, "type": "spapr-cpu-core",
       "vcpus-count": 2,
       "qom-path": "/machine/unattached/device[0]"}
   ]}'

TODO:
  add 'node' property for core <-> numa node mapping

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
it's only compile tested
v2:
 - s/qmp_query_hotpluggable_cpus/MachineClass->query_hotpluggable_cpus/ callback
---
 hw/ppc/spapr.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 24cfb05..4e65996 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -65,6 +65,7 @@
 #include "hw/compat.h"
 #include "qemu-common.h"
 #include "hw/ppc/spapr_cpu_core.h"
+#include "qmp-commands.h"
 
 #include <libfdt.h>
 
@@ -2389,6 +2390,37 @@ static unsigned spapr_cpu_index_to_socket_id(unsigned cpu_index)
     return cpu_index / smp_threads / smp_cores;
 }
 
+static HotpluggableCPUList *spapr_query_hotpluggable_cpus(MachineState *machine)
+{
+    int i;
+    HotpluggableCPUList *head = NULL;
+    sPAPRMachineState *spapr = SPAPR_MACHINE(machine);
+    int spapr_max_cores = max_cpus / smp_threads;
+
+    for (i = 0; i < spapr_max_cores; i++) {
+        HotpluggableCPUList *list_item = g_new0(typeof(*list_item), 1);
+        HotpluggableCPU *cpu_item = g_new0(typeof(*cpu_item), 1);
+        CpuInstanceProperties *cpu_props = g_new0(typeof(*cpu_props), 1);
+
+        cpu_item->type = g_strdup(TYPE_SPAPR_CPU_CORE);
+        cpu_item->vcpus_count = smp_threads;
+        cpu_props->has_core = true;
+        cpu_props->core = i;
+        /* TODO: add 'has_node/node' here to describe
+           to which node core belongs */
+
+        cpu_item->props = cpu_props;
+        if (spapr->cores[i]) {
+            cpu_item->has_qom_path = true;
+            cpu_item->qom_path = object_get_canonical_path(spapr->cores[i]);
+        }
+        list_item->value = cpu_item;
+        list_item->next = head;
+        head = list_item;
+    }
+    return head;
+}
+
 static void spapr_machine_class_init(ObjectClass *oc, void *data)
 {
     MachineClass *mc = MACHINE_CLASS(oc);
@@ -2418,6 +2450,7 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
     hc->plug = spapr_machine_device_plug;
     hc->unplug = spapr_machine_device_unplug;
     mc->cpu_index_to_socket_id = spapr_cpu_index_to_socket_id;
+    mc->query_hotpluggable_cpus = spapr_query_hotpluggable_cpus;
 
     smc->dr_lmb_enabled = true;
     smc->dr_cpu_enabled = true;
-- 
1.8.3.1