qmp: add QMP interface "query-cpu-model-comparison"

Let's provide a standardized interface to compare two CPU models.
"query-cpu-model-compare" takes two models and returns  how they compare
in a specific configuration.

The result will give guarantees about runnability. E.g. if a CPU model A
is a subset of CPU model B, model A is guaranteed to run in configurations
where model B runs, but not the other way around (might or might not run).

Usually, CPU features or CPU generations are used to calculate the result.
If a model is not guaranteed to run in a certain environment (e.g.
incompatible), a  compatible one can be created by "baselining" both models
(follow up patch).

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Message-Id: <20160905085244.99980-27-dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/stubs/arch-query-cpu-model-comparison.c b/stubs/arch-query-cpu-model-comparison.c
new file mode 100644
index 0000000000..d5486ae980
--- /dev/null
+++ b/stubs/arch-query-cpu-model-comparison.c
@@ -0,0 +1,12 @@
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "sysemu/arch_init.h"
+#include "qapi/qmp/qerror.h"
+
+CpuModelCompareInfo *arch_query_cpu_model_comparison(CpuModelInfo *modela,
+                                                     CpuModelInfo *modelb,
+                                                     Error **errp)
+{
+    error_setg(errp, QERR_UNSUPPORTED);
+    return NULL;
+}