[libvirt] [PATCH 16/23] cputest: Use CPU models from QEMU when available

[Jiri Denemark]

When testing cpuDecode for computing guest CPU definition from CPUID
data (the CPU definition reported by domain capabilities), we need to
use CPU models (and their usability blockers) from QEMU if they are
available to cpuDecode in the same way it is actually used in the qemu
driver.

Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
---
 tests/cputest.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 75 insertions(+), 6 deletions(-)

diff --git a/tests/cputest.c b/tests/cputest.c
index b72c17a168..18618ad309 100644
--- a/tests/cputest.c
+++ b/tests/cputest.c
@@ -515,6 +515,37 @@ cpuTestMakeQEMUCaps(const struct data *data)
     qemuCaps = NULL;
     goto cleanup;
 }
+
+
+static virDomainCapsCPUModelsPtr
+cpuTestGetCPUModels(const struct data *data)
+{
+    virDomainCapsCPUModelsPtr models = NULL;
+    virQEMUCapsPtr qemuCaps;
+
+    if (data->flags != JSON_MODELS)
+        return NULL;
+
+    if (!(qemuCaps = cpuTestMakeQEMUCaps(data)))
+        return NULL;
+
+    models = virQEMUCapsGetCPUDefinitions(qemuCaps, VIR_DOMAIN_VIRT_KVM);
+    if (models)
+        virObjectRef(models);
+
+    virObjectUnref(qemuCaps);
+
+    return models;
+}
+
+#else /* if WITH_QEMU && WITH_YAJL */
+
+static virDomainCapsCPUModelsPtr
+cpuTestGetCPUModels(const struct data *data ATTRIBUTE_UNUSED)
+{
+    return NULL;
+}
+
 #endif
 
 
@@ -528,6 +559,7 @@ cpuTestCPUID(bool guest, const void *arg)
     char *host = NULL;
     virCPUDefPtr cpu = NULL;
     char *result = NULL;
+    virDomainCapsCPUModelsPtr models = NULL;
 
     if (virAsprintf(&hostFile, "%s/cputestdata/%s-cpuid-%s.xml",
                     abs_srcdir, virArchToString(data->arch), data->host) < 0)
@@ -549,7 +581,10 @@ cpuTestCPUID(bool guest, const void *arg)
         cpu->type = VIR_CPU_TYPE_HOST;
     }
 
-    if (cpuDecode(cpu, hostData, NULL) < 0)
+    if (guest)
+        models = cpuTestGetCPUModels(data);
+
+    if (cpuDecode(cpu, hostData, models) < 0)
         goto cleanup;
 
     if (virAsprintf(&result, "cpuid-%s-%s",
@@ -565,6 +600,7 @@ cpuTestCPUID(bool guest, const void *arg)
     virCPUDataFree(hostData);
     virCPUDefFree(cpu);
     VIR_FREE(result);
+    virObjectUnref(models);
     return ret;
 }
 
@@ -686,6 +722,8 @@ cpuTestUpdateLive(const void *arg)
     virCPUDataPtr disabledData = NULL;
     char *expectedFile = NULL;
     virCPUDefPtr expected = NULL;
+    virDomainCapsCPUModelsPtr hvModels = NULL;
+    virDomainCapsCPUModelsPtr models = NULL;
     int ret = -1;
 
     if (virAsprintf(&cpuFile, "cpuid-%s-guest", data->host) < 0 ||
@@ -704,13 +742,42 @@ cpuTestUpdateLive(const void *arg)
         !(disabledData = virCPUDataParse(disabled)))
         goto cleanup;
 
-    if (virCPUUpdateLive(data->arch, cpu, enabledData, disabledData) < 0)
-        goto cleanup;
-
     if (virAsprintf(&expectedFile, "cpuid-%s-json", data->host) < 0 ||
         !(expected = cpuTestLoadXML(data->arch, expectedFile)))
         goto cleanup;
 
+    /* In case the host CPU signature does not exactly match any CPU model from
+     * cpu_map.xml, the CPU model we detect from CPUID may differ from the one
+     * we compute by asking QEMU. Since this test expands both CPU models and
+     * compares their features, we can try to translate the 'actual' CPU to
+     * use the CPU model from 'expected'.
+     */
+    if (STRNEQ(cpu->model, expected->model)) {
+        virDomainCapsCPUModelPtr hvModel;
+        char **blockers = NULL;
+        virDomainCapsCPUUsable usable = VIR_DOMCAPS_CPU_USABLE_UNKNOWN;
+
+        if (!(models = virDomainCapsCPUModelsNew(0)))
+            goto cleanup;
+
+        if ((hvModels = cpuTestGetCPUModels(data)) &&
+            virCPUModelIsAllowed(expected->model, hvModels, &hvModel)) {
+            blockers = hvModel->blockers;
+            usable = hvModel->usable;
+        }
+
+        if (virDomainCapsCPUModelsAdd(models, expected->model, -1,
+                                      usable, blockers) < 0)
+            goto cleanup;
+
+        cpu->fallback = VIR_CPU_FALLBACK_ALLOW;
+        ignore_value(virCPUTranslate(data->arch, cpu, models));
+        cpu->fallback = VIR_CPU_FALLBACK_FORBID;
+    }
+
+    if (virCPUUpdateLive(data->arch, cpu, enabledData, disabledData) < 0)
+        goto cleanup;
+
     ret = cpuTestUpdateLiveCompare(data->arch, cpu, expected);
 
  cleanup:
@@ -724,6 +791,8 @@ cpuTestUpdateLive(const void *arg)
     virCPUDataFree(disabledData);
     VIR_FREE(expectedFile);
     virCPUDefFree(expected);
+    virObjectUnref(hvModels);
+    virObjectUnref(models);
     return ret;
 }
 
@@ -915,11 +984,11 @@ mymain(void)
         DO_TEST(arch, cpuTestHostCPUID, host, host,                     \
                 NULL, NULL, 0, 0);                                      \
         DO_TEST(arch, cpuTestGuestCPUID, host, host,                    \
-                NULL, NULL, 0, 0);                                      \
+                NULL, NULL, json, 0);                                   \
         DO_TEST_CPUID_JSON(arch, host, json);                           \
         if (json != JSON_NONE) {                                        \
             DO_TEST(arch, cpuTestUpdateLive, host, host,                \
-                    NULL, NULL, 0, 0);                                  \
+                    NULL, NULL, json, 0);                               \
         }                                                               \
     } while (0)
 
-- 
2.14.2