[libvirt] [RFCv2 PATCH 4/5] conf: Introduce cputune/memorytune to support memory bandwidth allocation

From: Bing Niu <bing.niu(a)intel.com&gt; Introduce a new section memorytune to support memory bandwidth allocation. This is consistent with existing cachetune . As the example below: <memorytune vcpus='0'> <node id='0' bandwidth='30'/> </memorytune> id --- on which node memory bandwidth to be set bandwidth --- the memory bandwidth percent to set. Signed-off-by: Bing Niu <bing.niu(a)intel.com&gt; --- src/conf/domain_conf.c | 260 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 260 insertions(+) diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index b3543f3..dbfd69f 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -19076,6 +19076,189 @@ virDomainCachetuneDefParse(virDomainDefPtr def, } +static int +virDomainMemorytuneDefParseMemory(xmlXPathContextPtr ctxt, + xmlNodePtr node, + virResctrlAllocPtr alloc) +{ + xmlNodePtr oldnode = ctxt->node; + unsigned int id; + unsigned int bandwidth; + char *tmp = NULL; + int ret = -1; + + ctxt->node = node; + + tmp = virXMLPropString(node, "id"); + if (!tmp) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("Missing memorytune attribute 'id'")); + goto cleanup; + } + if (virStrToLong_uip(tmp, NULL, 10, &id) < 0) { + virReportError(VIR_ERR_XML_ERROR, + _("Invalid memorytune attribute 'id' value '%s'"), + tmp); + goto cleanup; + } + VIR_FREE(tmp); + + tmp = virXMLPropString(node, "bandwidth"); + if (!tmp) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("Missing memorytune attribute 'bandwidth'")); + goto cleanup; + } + if (virStrToLong_uip(tmp, NULL, 10, &bandwidth) < 0) { + virReportError(VIR_ERR_XML_ERROR, + _("Invalid memorytune attribute 'bandwidth' value '%s'"), + tmp); + goto cleanup; + } + VIR_FREE(tmp); + if (virResctrlSetMemoryBandwidth(alloc, id, bandwidth) < 0) + goto cleanup; + + ret = 0; + cleanup: + ctxt->node = oldnode; + VIR_FREE(tmp); + return ret; +} + + +static int +virDomainMemorytuneDefParse(virDomainDefPtr def, + xmlXPathContextPtr ctxt, + xmlNodePtr node, + unsigned int flags) +{ + xmlNodePtr oldnode = ctxt->node; + xmlNodePtr *nodes = NULL; + virBitmapPtr vcpus = NULL; + virResctrlAllocPtr alloc = NULL; + virDomainRestuneDefPtr tmp_cachetune = NULL; + char *tmp = NULL; + char *vcpus_str = NULL; + char *alloc_id = NULL; + ssize_t i = 0; + int n; + int ret = -1; + bool new_alloc = false; + + ctxt->node = node; + + if (VIR_ALLOC(tmp_cachetune) < 0) + goto cleanup; + + vcpus_str = virXMLPropString(node, "vcpus"); + if (!vcpus_str) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("Missing memorytune attribute 'vcpus'")); + goto cleanup; + } + if (virBitmapParse(vcpus_str, &vcpus, VIR_DOMAIN_CPUMASK_LEN) < 0) { + virReportError(VIR_ERR_XML_ERROR, + _("Invalid memorytune attribute 'vcpus' value '%s'"), + vcpus_str); + goto cleanup; + } + + /* We need to limit the bitmap to number of vCPUs. If there's nothing left, + * then we can just clean up and return 0 immediately */ + virBitmapShrink(vcpus, def->maxvcpus); + + if (virBitmapIsAllClear(vcpus)) { + ret = 0; + goto cleanup; + } + + if ((n = virXPathNodeSet("./node", ctxt, &nodes)) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("Cannot extract memory nodes under memorytune")); + goto cleanup; + } + for (i = 0; i < def->nrestunes; i++) { + /* vcpus group has been created, directly use the existing one. + * Just updating memory allocation information of that group + * */ + if (virBitmapEqual(def->restunes[i]->vcpus, vcpus)) { + alloc = def->restunes[i]->alloc; + break; + } + + /* vcpus can not overlapping */ + if (virBitmapOverlaps(def->restunes[i]->vcpus, vcpus)) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("Overlapping vcpus in memorytunes")); + goto cleanup; + } + } + + if (!alloc) { + alloc = virResctrlAllocNew(); + new_alloc = true; + } + + for (i = 0; i < n; i++) { + if (virDomainMemorytuneDefParseMemory(ctxt, nodes[i], alloc) < 0) + goto cleanup; + } + /* + * If this is a new allocation, format ID and append to restune, otherwise + * just update the existing alloc information + * */ + if (new_alloc) { + if (virResctrlAllocIsEmpty(alloc)) { + ret = 0; + goto cleanup; + } + + + /* We need to format it back because we need to be consistent in the naming + * even when users specify some "sub-optimal" string there. */ + VIR_FREE(vcpus_str); + vcpus_str = virBitmapFormat(vcpus); + if (!vcpus_str) + goto cleanup; + + if (!(flags & VIR_DOMAIN_DEF_PARSE_INACTIVE)) + alloc_id = virXMLPropString(node, "id"); + + if (!alloc_id) { + /* The number of allocations is limited and the directory structure is flat, + * not hierarchical, so we need to have all same allocations in one + * directory, so it's nice to have it named appropriately. For now it's + * 'vcpus_...' but it's designed in order for it to be changeable in the + * future (it's part of the status XML). */ + if (virAsprintf(&alloc_id, "vcpus_%s", vcpus_str) < 0) + goto cleanup; + } + + if (virResctrlAllocSetID(alloc, alloc_id) < 0) + goto cleanup; + + VIR_STEAL_PTR(tmp_cachetune->vcpus, vcpus); + VIR_STEAL_PTR(tmp_cachetune->alloc, alloc); + + if (VIR_APPEND_ELEMENT(def->restunes, def->nrestunes, tmp_cachetune) < 0) + goto cleanup; + } + ret = 0; + cleanup: + ctxt->node = oldnode; + virDomainRestuneDefFree(tmp_cachetune); + if (new_alloc) + virObjectUnref(alloc); + virBitmapFree(vcpus); + VIR_FREE(alloc_id); + VIR_FREE(vcpus_str); + VIR_FREE(nodes); + VIR_FREE(tmp); + return ret; +} + + static virDomainDefPtr virDomainDefParseXML(xmlDocPtr xml, xmlNodePtr root, @@ -19671,6 +19854,18 @@ virDomainDefParseXML(xmlDocPtr xml, } VIR_FREE(nodes); + if ((n = virXPathNodeSet("./cputune/memorytune", ctxt, &nodes)) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("cannot extract memorytune nodes")); + goto error; + } + + for (i = 0; i < n; i++) { + if (virDomainMemorytuneDefParse(def, ctxt, nodes[i], flags) < 0) + goto error; + } + VIR_FREE(nodes); + if (virCPUDefParseXML(ctxt, "./cpu[1]", VIR_CPU_TYPE_GUEST, &def->cpu) < 0) goto error; @@ -26922,6 +27117,68 @@ virDomainCachetuneDefFormat(virBufferPtr buf, static int +virDomainMemorytuneDefFormatHelper(unsigned int id, + unsigned int bandwidth, + void *opaque) +{ + virBufferPtr buf = opaque; + + virBufferAsprintf(buf, + "<node id='%u' bandwidth='%u'/>\n", + id, bandwidth); + return 0; +} + + +static int +virDomainMemorytuneDefFormat(virBufferPtr buf, + virDomainRestuneDefPtr restune, + unsigned int flags) +{ + virBuffer childrenBuf = VIR_BUFFER_INITIALIZER; + char *vcpus = NULL; + int ret = -1; + + virBufferSetChildIndent(&childrenBuf, buf); + virResctrlAllocForeachMemory(restune->alloc, + virDomainMemorytuneDefFormatHelper, + &childrenBuf); + + + if (virBufferCheckError(&childrenBuf) < 0) + goto cleanup; + + if (!virBufferUse(&childrenBuf)) { + ret = 0; + goto cleanup; + } + + vcpus = virBitmapFormat(restune->vcpus); + if (!vcpus) + goto cleanup; + + virBufferAsprintf(buf, "<memorytune vcpus='%s'", vcpus); + + if (!(flags & VIR_DOMAIN_DEF_FORMAT_INACTIVE)) { + const char *alloc_id = virResctrlAllocGetID(restune->alloc); + if (!alloc_id) + goto cleanup; + + virBufferAsprintf(buf, " id='%s'", alloc_id); + } + virBufferAddLit(buf, ">\n"); + + virBufferAddBuffer(buf, &childrenBuf); + virBufferAddLit(buf, "</memorytune>\n"); + + ret = 0; + cleanup: + virBufferFreeAndReset(&childrenBuf); + VIR_FREE(vcpus); + return ret; +} + +static int virDomainCputuneDefFormat(virBufferPtr buf, virDomainDefPtr def, unsigned int flags) @@ -27026,6 +27283,9 @@ virDomainCputuneDefFormat(virBufferPtr buf, for (i = 0; i < def->nrestunes; i++) virDomainCachetuneDefFormat(&childrenBuf, def->restunes[i], flags); + for (i = 0; i < def->nrestunes; i++) + virDomainMemorytuneDefFormat(&childrenBuf, def->restunes[i], flags); + if (virBufferCheckError(&childrenBuf) < 0) return -1; -- 2.7.4