[Qemu-devel] [PATCH v2 4/6] qmp: Add runnability information to query-cpu-definitions

[Eduardo Habkost <ehabkost@redhat.com>]

Extend query-cpu-definitions schema to allow it to return two new
optional fields: "runnable" and "unavailable-features".
"runnable" will tell if the CPU model can be run in the current
host. "unavailable-features" will contain a list of CPU
properties that are preventing the CPU model from running in the
current host.

Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Michael Mueller <mimu@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Jiri Denemark <jdenemar@redhat.com>
Cc: libvir-list@redhat.com
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
Changes v1 -> v2:
* Remove @runnable field, non-empty @unavailable-features is
  enough to report CPU model as not runnable.
* Documentation updates:
  * Changed to "(since 2.7)";
  * Add more details about the exact meaning of
    unavailable-features, and what it would mean to see
    read-only QOM properties in the list, and that
    implementations can return "type" if there's
    no extra information available;
---
 qapi-schema.json | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/qapi-schema.json b/qapi-schema.json
index 8483bdf..43478e9 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -3005,11 +3005,32 @@
 # Virtual CPU definition.
 #
 # @name: the name of the CPU definition
+# @unavailable-features: #optional List of properties that prevent
+#                        the CPU model from running in the current
+#                        host. (since 2.7)
+#
+# @unavailable-features is a list of QOM property names that
+# represent CPU model attributes that prevent the CPU from running.
+# If the QOM property is read-only, that means there's no known
+# way to make the CPU model run in the current host. If
+# absolutely no extra information will be returned to explain why
+# the CPU model is not runnable, implementations may simply
+# return "type" as the property name.
+# If the property is read-write, it means that it MAY be possible
+# to run the CPU model in the current host if that property is
+# changed. Management software can use it as hints to suggest or
+# choose an alternative for the user, or just to generate meaningful
+# error messages explaining why the CPU model can't be used.
+# If @unavailable-features is an empty list, the CPU model is
+# runnable using the current host and machine-type.
+# If @unavailable-features is not present, runnability
+# information for the CPU is not available.
 #
 # Since: 1.2.0
 ##
 { 'struct': 'CpuDefinitionInfo',
-  'data': { 'name': 'str' } }
+  'data': { 'name': 'str',
+            '*unavailable-features': [ 'str' ] } }
 
 ##
 # @query-cpu-definitions:
-- 
2.5.5