Re: [libvirt] [PATCH 1/5] conf: add support for specifying CPU "dies" parameter

Recently CPU hardware vendors have started to support a new level of inside the CPU package topology known as a "die". Thus the hierarchy

is now: sockets > dies > cores > threads This adds support for "dies" in the XML parser, with the value defaulting to 1 if not specified for backwards compatibility. For example a system with 64 logical CPUs might report <topology sockets="4" dies="2" cores="4" threads="2"/> Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt;

diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index dd04a05f09..1433ff7043 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in

@@ -1675,10 +1675,10 @@ <dd>The <code>topology</code> element specifies requested topology of virtual CPU provided to the guest. Three non-zero values have to be given for <code>sockets</code>, <code>cores</code>, and - <code>threads</code>: total number of CPU sockets, number of cores per - socket, and number of threads per core, respectively. Hypervisors may - require that the maximum number of vCPUs specified by the - <code>cpus</code> element equals to the number of vcpus resulting + <code>threads</code>: total number of CPU sockets, dies per socket, + number of cores per die, and number of threads per core, respectively. + Hypervisors may require that the maximum number of vCPUs specified by + the <code>cpus</code> element equals to the number of vcpus resulting from the topology.</dd>

<dt><code>feature</code></dt>

diff --git a/src/conf/cpu_conf.c b/src/conf/cpu_conf.c index 7490d6bf73..c874c47354 100644 --- a/src/conf/cpu_conf.c +++ b/src/conf/cpu_conf.c

@@ -535,6 +536,12 @@ virCPUDefParseXML(xmlXPathContextPtr ctxt, } def->sockets = (unsigned int) ul; + if (virXPathULong("string(./topology[1]/@dies)", ctxt, &ul) < 0) { + def->dies = 1; + } else { + def->dies = (unsigned int) ul; + } +

if (virXPathULong("string(./topology[1]/@cores)", ctxt, &ul) < 0) { virReportError(VIR_ERR_XML_ERROR, "%s", _("Missing 'cores' attribute in CPU topology"));