Re: [libvirt] [PATCH v4 02/11] nvdimm: introduce 'pmem' element into xml for NVDIMM memory

On Mon, Dec 17, 2018 at 05:26:12PM +0800, Luyao Zhong wrote: > The 'pmem' option allows users to specify whether the backend > storage of memory-backend-file is a real persistent memory: What does this actually do in practice ? Why does it matter and if it does, why can't libvirt set the right value automatically instad of needing the user to set the XML.

> > <devices> > ... > <memory model='nvdimm' access='shared'> > <source> > <path>/dev/dax0.0</path> > <pmem/> > </source> > <target> > <size unit='MiB'>4094</size> > <node>0</node> > <label> > <size unit='MiB'>2</size> > </label> > </target> > </memory> > ... > </devices> > > Signed-off-by: Luyao Zhong <luyao.zhong(a)intel.com&gt; > --- > docs/formatdomain.html.in | 12 +++++ > docs/schemas/domaincommon.rng | 5 ++ > src/conf/domain_conf.c | 13 +++++ > src/conf/domain_conf.h | 1 + > .../memory-hotplug-nvdimm-pmem.xml | 58 ++++++++++++++++++++++ > .../memory-hotplug-nvdimm-unarmed.xml | 58 ++++++++++++++++++++++ > tests/qemuxml2xmltest.c | 1 + > 7 files changed, 148 insertions(+) > create mode 100644 tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.xml > create mode 100644 tests/qemuxml2argvdata/memory-hotplug-nvdimm-unarmed.xml > > diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in > index 74e02a4..0f50da6 100644 > --- a/docs/formatdomain.html.in > +++ b/docs/formatdomain.html.in > @@ -8323,6 +8323,7 @@ qemu-kvm -net nic,model=? /dev/null > &lt;source&gt; > &lt;path&gt;/tmp/nvdimm&lt;/path&gt; > &lt;alignsize unit='KiB'&gt;2048&lt;/alignsize&gt; > + &lt;pmem/&gt; > &lt;/source&gt; > &lt;target&gt; > &lt;size unit='KiB'&gt;524288&lt;/size&gt; > @@ -8423,6 +8424,17 @@ qemu-kvm -net nic,model=? /dev/null > <span class="since">Since 5.0.0</span> > </p> > </dd> > + > + <dt><code>pmem</code></dt> > + <dd> > + <p> > + This element can be used to specify whether the backend storage > + of memory-backend-file is a real persistent memory. If the > + backend is a real persistence memory and <code>pmem</code> is set, > + QEMU will guarantee the persistence of its own writes to the > + vNVDIMM backend. <span class="since">Since 5.0.0</span> > + </p> > + </dd> > </dl> > </dd> > > diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng > index 395a7ea..734589e 100644 > --- a/docs/schemas/domaincommon.rng > +++ b/docs/schemas/domaincommon.rng > @@ -5393,6 +5393,11 @@ > <ref name="scaledInteger"/> > </element> > </optional> > + <optional> > + <element name="pmem"> > + <empty/> > + </element> > + </optional> > </interleave> > </group> > </choice> > diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c > index 7e59d8c..9edaf6d 100644 > --- a/src/conf/domain_conf.c > +++ b/src/conf/domain_conf.c > @@ -15785,6 +15785,9 @@ virDomainMemorySourceDefParseXML(xmlNodePtr node, > &def->alignsize, false, false) < 0) > goto cleanup; > > + if (virXPathBoolean("boolean(./pmem)", ctxt)) > + def->nvdimmPmem = true; > + > break; > > case VIR_DOMAIN_MEMORY_MODEL_NONE: > @@ -22756,6 +22759,13 @@ virDomainMemoryDefCheckABIStability(virDomainMemoryDefPtr src, > src->alignsize, dst->alignsize); > return false; > } > + > + if (src->nvdimmPmem != dst->nvdimmPmem) { > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", > + _("Target NVDIMM pmem flag doesn't match " > + "source NVDIMM pmem flag")); > + return false; > + } > } > > return virDomainDeviceInfoCheckABIStability(&src->info, &dst->info); > @@ -26296,6 +26306,9 @@ virDomainMemorySourceDefFormat(virBufferPtr buf, > if (def->alignsize) > virBufferAsprintf(buf, "<alignsize unit='KiB'>%llu</alignsize>\n", > def->alignsize); > + > + if (def->nvdimmPmem) > + virBufferAddLit(buf, "<pmem/>\n"); > break; > > case VIR_DOMAIN_MEMORY_MODEL_NONE: > diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h > index 848bd94..a63afdc 100644 > --- a/src/conf/domain_conf.h > +++ b/src/conf/domain_conf.h > @@ -2148,6 +2148,7 @@ struct _virDomainMemoryDef { > unsigned long long pagesize; /* kibibytes */ > char *nvdimmPath; > unsigned long long alignsize; /* kibibytes; valid only for NVDIMM */ > + bool nvdimmPmem; /* valid only for NVDIMM */ > > /* target */ > int model; /* virDomainMemoryModel */ > diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.xml b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.xml > new file mode 100644 > index 0000000..060d75c > --- /dev/null > +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.xml > @@ -0,0 +1,58 @@ > +<domain type='qemu'> > + <name>QEMUGuest1</name> > + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> > + <maxMemory slots='16' unit='KiB'>1099511627776</maxMemory> > + <memory unit='KiB'>1267710</memory> > + <currentMemory unit='KiB'>1267710</currentMemory> > + <vcpu placement='static' cpuset='0-1'>2</vcpu> > + <os> > + <type arch='i686' machine='pc'>hvm</type> > + <boot dev='hd'/> > + </os> > + <idmap> > + <uid start='0' target='1000' count='10'/> > + <gid start='0' target='1000' count='10'/> > + </idmap> > + <cpu> > + <topology sockets='2' cores='1' threads='1'/> > + <numa> > + <cell id='0' cpus='0-1' memory='219136' unit='KiB'/> > + </numa> > + </cpu> > + <clock offset='utc'/> > + <on_poweroff>destroy</on_poweroff> > + <on_reboot>restart</on_reboot> > + <on_crash>destroy</on_crash> > + <devices> > + <emulator>/usr/bin/qemu-system-i686</emulator> > + <disk type='block' device='disk'> > + <driver name='qemu' type='raw'/> > + <source dev='/dev/HostVG/QEMUGuest1'/> > + <target dev='hda' bus='ide'/> > + <address type='drive' controller='0' bus='0' target='0' unit='0'/> > + </disk> > + <controller type='ide' index='0'> > + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> > + </controller> > + <controller type='usb' index='0'> > + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> > + </controller> > + <controller type='pci' index='0' model='pci-root'/> > + <input type='mouse' bus='ps2'/> > + <input type='keyboard' bus='ps2'/> > + <memballoon model='virtio'> > + <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> > + </memballoon> > + <memory model='nvdimm' access='private'> > + <source> > + <path>/tmp/nvdimm</path> > + <pmem/> > + </source> > + <target> > + <size unit='KiB'>523264</size> > + <node>0</node> > + </target> > + <address type='dimm' slot='0'/> > + </memory> > + </devices> > +</domain> > diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-unarmed.xml b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-unarmed.xml > new file mode 100644 > index 0000000..7ddbb01 > --- /dev/null > +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-unarmed.xml > @@ -0,0 +1,58 @@ > +<domain type='qemu'> > + <name>QEMUGuest1</name> > + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> > + <maxMemory slots='16' unit='KiB'>1099511627776</maxMemory> > + <memory unit='KiB'>1267710</memory> > + <currentMemory unit='KiB'>1267710</currentMemory> > + <vcpu placement='static' cpuset='0-1'>2</vcpu> > + <os> > + <type arch='i686' machine='pc'>hvm</type> > + <boot dev='hd'/> > + </os> > + <idmap> > + <uid start='0' target='1000' count='10'/> > + <gid start='0' target='1000' count='10'/> > + </idmap> > + <cpu> > + <topology sockets='2' cores='1' threads='1'/> > + <numa> > + <cell id='0' cpus='0-1' memory='219136' unit='KiB'/> > + </numa> > + </cpu> > + <clock offset='utc'/> > + <on_poweroff>destroy</on_poweroff> > + <on_reboot>restart</on_reboot> > + <on_crash>destroy</on_crash> > + <devices> > + <emulator>/usr/bin/qemu-system-i686</emulator> > + <disk type='block' device='disk'> > + <driver name='qemu' type='raw'/> > + <source dev='/dev/HostVG/QEMUGuest1'/> > + <target dev='hda' bus='ide'/> > + <address type='drive' controller='0' bus='0' target='0' unit='0'/> > + </disk> > + <controller type='ide' index='0'> > + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> > + </controller> > + <controller type='usb' index='0'> > + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> > + </controller> > + <controller type='pci' index='0' model='pci-root'/> > + <input type='mouse' bus='ps2'/> > + <input type='keyboard' bus='ps2'/> > + <memballoon model='virtio'> > + <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> > + </memballoon> > + <memory model='nvdimm' access='private'> > + <source> > + <path>/tmp/nvdimm</path> > + </source> > + <target> > + <size unit='KiB'>523264</size> > + <node>0</node> > + <unarmed/> > + </target> > + <address type='dimm' slot='0'/> > + </memory> > + </devices> > +</domain> > diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c > index 5161f4a..ef3ece8 100644 > --- a/tests/qemuxml2xmltest.c > +++ b/tests/qemuxml2xmltest.c > @@ -1117,6 +1117,7 @@ mymain(void) > DO_TEST("memory-hotplug-nvdimm-access", NONE); > DO_TEST("memory-hotplug-nvdimm-label", NONE); > DO_TEST("memory-hotplug-nvdimm-align", NONE); > + DO_TEST("memory-hotplug-nvdimm-pmem", NONE); > DO_TEST("net-udp", NONE); > > DO_TEST("video-virtio-gpu-device", NONE); > -- > 2.7.4 > > -- > libvir-list mailing list > libvir-list(a)redhat.com > https://www.redhat.com/mailman/listinfo/libvir-list Regards, Daniel