Re: [libvirt] [PATCH 4/6] qemu-caps: Get host model directly from Qemu when available

From: "Collin L. Walling" <walling(a)linux.vnet.ibm.com&gt; When qmp query-cpu-model-expansion is available probe Qemu for its view of the host model. In kvm environments this can provide a more complete view of the host model because features supported by Qemu and Kvm can be considered. Signed-off-by: Collin L. Walling <walling(a)linux.vnet.ibm.com&gt; Signed-off-by: Jason J. Herne <jjherne(a)linux.vnet.ibm.com&gt; --- src/qemu/qemu_capabilities.c | 109 +++++++++++++++++++++++++++++++++++++++++-- src/qemu/qemu_capabilities.h | 1 + 2 files changed, 105 insertions(+), 5 deletions(-) diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index cfd090c..b2c70cf 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -352,6 +352,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST, "ivshmem-doorbell", /* 240 */ "query-qmp-schema", "gluster.debug_level", + "query-cpu-model-expansion", ); @@ -394,6 +395,8 @@ struct _virQEMUCaps { size_t ngicCapabilities; virGICCapability *gicCapabilities; + qemuMonitorCPUModelInfoPtr hostCPUModelInfo; + /* Anything below is not stored in the cache since the values are * re-computed from the other fields or external data sources every * time we probe QEMU or load the results from the cache. @@ -1493,7 +1496,8 @@ struct virQEMUCapsStringFlags virQEMUCapsCommands[] = { { "rtc-reset-reinjection", QEMU_CAPS_RTC_RESET_REINJECTION }, { "migrate-incoming", QEMU_CAPS_INCOMING_DEFER }, { "query-hotpluggable-cpus", QEMU_CAPS_QUERY_HOTPLUGGABLE_CPUS }, - { "query-qmp-schema", QEMU_CAPS_QUERY_QMP_SCHEMA } + { "query-qmp-schema", QEMU_CAPS_QUERY_QMP_SCHEMA }, + { "query-cpu-model-expansion", QEMU_CAPS_QUERY_CPU_MODEL_EXPANSION}, }; struct virQEMUCapsStringFlags virQEMUCapsMigration[] = { @@ -2131,6 +2135,10 @@ virQEMUCapsPtr virQEMUCapsNewCopy(virQEMUCapsPtr qemuCaps) !(ret->hostCPUModel = virCPUDefCopy(qemuCaps->hostCPUModel))) goto error; + if (qemuCaps->hostCPUModelInfo && + !(ret->hostCPUModelInfo = qemuMonitorCPUModelInfoCopy(qemuCaps->hostCPUModelInfo))) + goto error; + if (VIR_ALLOC_N(ret->machineTypes, qemuCaps->nmachineTypes) < 0) goto error; ret->nmachineTypes = qemuCaps->nmachineTypes; @@ -2741,6 +2749,18 @@ virQEMUCapsProbeQMPCPUDefinitions(virQEMUCapsPtr qemuCaps, return ret; } +static int +virQEMUCapsProbeQMPHostCPU(virQEMUCapsPtr qemuCaps, + qemuMonitorPtr mon)

+{ + if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_QUERY_CPU_MODEL_EXPANSION) || + !virQEMUCapsGet(qemuCaps, QEMU_CAPS_KVM)) + return 0; + + return qemuMonitorGetCPUModelExpansion(mon, "static", "host", + &qemuCaps->hostCPUModelInfo); +} + struct tpmTypeToCaps { int type; virQEMUCapsFlags caps; @@ -2966,6 +2986,29 @@ virQEMUCapsCPUFilterFeatures(const char *name, } +static int +virQEMUCapsCopyModelFromQEMU(virCPUDefPtr dst, + const qemuMonitorCPUModelInfo *modelInfo) +{ + size_t i; + + if (VIR_STRDUP(dst->model, modelInfo->name) < 0 || + VIR_ALLOC_N(dst->features, modelInfo->nprops) < 0) + return -1; + dst->nfeatures_max = modelInfo->nprops; + dst->nfeatures = 0; + + for (i = 0; i < modelInfo->nprops; i++) { + if (VIR_STRDUP(dst->features[i].name, modelInfo->props[i].name) < 0) + return -1; + dst->features[i].policy = VIR_CPU_FEATURE_REQUIRE;

+ dst->nfeatures++; + } + + return 0; +}

+ + void virQEMUCapsInitHostCPUModel(virQEMUCapsPtr qemuCaps, virCapsPtr caps) @@ -2978,7 +3021,8 @@ virQEMUCapsInitHostCPUModel(virQEMUCapsPtr qemuCaps, if (!virQEMUCapsGuestIsNative(caps->host.arch, qemuCaps->arch)) goto error; - if (caps->host.cpu && caps->host.cpu->model) { + if ((caps->host.cpu && caps->host.cpu->model) + || qemuCaps->hostCPUModelInfo) { if (VIR_ALLOC(cpu) < 0) goto error;

@@ -2987,9 +3031,14 @@ virQEMUCapsInitHostCPUModel(virQEMUCapsPtr qemuCaps, cpu->mode = VIR_CPU_MODE_CUSTOM; cpu->match = VIR_CPU_MATCH_EXACT; - if (virCPUDefCopyModelFilter(cpu, caps->host.cpu, true, - virQEMUCapsCPUFilterFeatures, NULL) < 0) - goto error; + if (qemuCaps->hostCPUModelInfo) { + if (virQEMUCapsCopyModelFromQEMU(cpu, qemuCaps->hostCPUModelInfo) < 0) + goto error; + } else { + if (virCPUDefCopyModelFilter(cpu, caps->host.cpu, true, + virQEMUCapsCPUFilterFeatures, NULL) < 0) + goto error; + } } qemuCaps->hostCPUModel = cpu; @@ -3031,6 +3080,7 @@ virQEMUCapsLoadCache(virCapsPtr caps, size_t i; int n; xmlNodePtr *nodes = NULL; + xmlNodePtr node = NULL; xmlXPathContextPtr ctxt = NULL; char *str = NULL; long long int l; @@ -3130,6 +3180,37 @@ virQEMUCapsLoadCache(virCapsPtr caps, } VIR_FREE(str); + if ((node = virXPathNode("./host/cpu", ctxt)) != NULL) { + xmlNodePtr oldnode = ctxt->node; + ctxt->node = node; + if ((str = virXPathString("string(./model)", ctxt))) { + if (VIR_ALLOC(qemuCaps->hostCPUModelInfo) < 0) + goto cleanup;

+ if (VIR_STRDUP(qemuCaps->hostCPUModelInfo->name, str) < 0) + goto cleanup; + } + if ((n = virXPathNodeSet("./feature", ctxt, &nodes)) > 0) { + if (VIR_ALLOC_N(qemuCaps->hostCPUModelInfo->props, n) < 0) + goto cleanup; + qemuCaps->hostCPUModelInfo->nprops = n; + for (i = 0; i < n; i++) { + if (!(str = virXMLPropString(nodes[i], "name"))) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("missing name for a host CPU model" + " feature in QEMU capabilities cache")); + goto cleanup; + } + if (VIR_STRDUP(qemuCaps->hostCPUModelInfo->props[i].name, str) < 0) + goto cleanup; + qemuCaps->hostCPUModelInfo->props[i].supported = true; + } + } + ctxt->node = oldnode; + node = NULL; + VIR_FREE(str); + } + VIR_FREE(nodes); +

if ((n = virXPathNodeSet("./cpu", ctxt, &nodes)) < 0) { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("failed to parse qemu capabilities cpus")); @@ -3310,6 +3391,23 @@ virQEMUCapsFormatCache(virQEMUCapsPtr qemuCaps, virBufferAsprintf(&buf, "<arch>%s</arch>\n", virArchToString(qemuCaps->arch)); + if (qemuCaps->hostCPUModelInfo) { + virBufferAddLit(&buf, "<host>\n"); + virBufferAdjustIndent(&buf, 2); + virBufferAddLit(&buf, "<cpu>\n"); + virBufferAdjustIndent(&buf, 2); + virBufferAsprintf(&buf, "<model>%s</model>\n", + qemuCaps->hostCPUModelInfo->name); + for (i = 0; i < qemuCaps->hostCPUModelInfo->nprops; i++) { + virBufferAsprintf(&buf, "<feature name='%s'/>\n", + qemuCaps->hostCPUModelInfo->props[i].name); + } + virBufferAdjustIndent(&buf, -2); + virBufferAddLit(&buf, "</cpu>\n"); + virBufferAdjustIndent(&buf, -2); + virBufferAddLit(&buf, "</host>\n"); + } +

if (qemuCaps->cpuDefinitions) { for (i = 0; i < qemuCaps->cpuDefinitions->nmodels; i++) { virDomainCapsCPUModelPtr cpu = qemuCaps->cpuDefinitions->models + i; @@ -3998,6 +4096,7 @@ virQEMUCapsInitQMPMonitor(virQEMUCapsPtr qemuCaps, goto cleanup; if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_QUERY_QMP_SCHEMA) && virQEMUCapsProbeQMPSchemaCapabilities(qemuCaps, mon) < 0) + if (virQEMUCapsProbeQMPHostCPU(qemuCaps, mon) < 0) goto cleanup;

/* 'intel-iommu' shows up as a device since 2.2.0, but can diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h index 9163572..82e1561 100644 --- a/src/qemu/qemu_capabilities.h +++ b/src/qemu/qemu_capabilities.h @@ -387,6 +387,7 @@ typedef enum { QEMU_CAPS_DEVICE_IVSHMEM_DOORBELL, /* -device ivshmem-doorbell */ QEMU_CAPS_QUERY_QMP_SCHEMA, /* query-qmp-schema command */ QEMU_CAPS_GLUSTER_DEBUG_LEVEL, /* -drive gluster.debug_level={0..9} */ + QEMU_CAPS_QUERY_CPU_MODEL_EXPANSION, /* qmp query-cpu-model-expansion */ QEMU_CAPS_LAST /* this must always be the last item */ } virQEMUCapsFlags;