[libvirt] [PATCH] conf: Disallow emulatorpin when numatune's in effect

[Michal Privoznik]

https://bugzilla.redhat.com/show_bug.cgi?id=1170492

In one of our previous commits (dc8b7ce7) we've obsoleted <cputune/>
in favor of <numatune/> and others. If old element was passed it was
basically ignored and interesting settings were copied from the new
one. Well with one exception we'd forgotten about: emulatorpin.
Imagine that domain is configured as follows:

  <vcpu placement='static' current='2'>6</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>

This is perfectly valid as only old style elements are used. However,
adding new style elements messes up the XML:

  <vcpu placement='auto' current='2'>6</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>

Since <numatune/> is auto, <vcpu/> becomes auto as well. However in
that case we can't guarantee that emulator will be pinned onto
selected nodes.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/conf/domain_conf.c                             | 12 +++++++-
 .../qemuxml2argv-cputune-numatune.xml              | 35 ++++++++++++++++++++++
 .../qemuxml2xmlout-cputune-numatune.xml            | 32 ++++++++++++++++++++
 tests/qemuxml2xmltest.c                            |  1 +
 4 files changed, 79 insertions(+), 1 deletion(-)
 create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-cputune-numatune.xml
 create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-cputune-numatune.xml

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 8792f5e..0b8af6d 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -13173,8 +13173,18 @@ virDomainDefParseXML(xmlDocPtr xml,
                                   ctxt) < 0)
         goto error;
 
-    if (virDomainNumatuneHasPlacementAuto(def->numatune) && !def->cpumask)
+    if (virDomainNumatuneHasPlacementAuto(def->numatune) && !def->cpumask) {
+        /* If numatune is used, it obsoletes some older settings
+         * like /domain/vcpu/@placement or
+         * /domain/cputune/emulatorpin. For more info see comment
+         * a few lines above where emulatorpin is parsed. */
         def->placement_mode = VIR_DOMAIN_CPU_PLACEMENT_MODE_AUTO;
+        if (def->cputune.emulatorpin) {
+            VIR_WARN("Ignore emulatorpin for <numatune> placement is 'auto'");
+            virDomainVcpuPinDefFree(def->cputune.emulatorpin);
+            def->cputune.emulatorpin = NULL;
+        }
+    }
 
     if ((n = virXPathNodeSet("./resource", ctxt, &nodes)) < 0) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-cputune-numatune.xml b/tests/qemuxml2argvdata/qemuxml2argv-cputune-numatune.xml
new file mode 100644
index 0000000..9759b48
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-cputune-numatune.xml
@@ -0,0 +1,35 @@
+<domain type='kvm'>
+  <name>dummy2</name>
+  <uuid>4d92ec27-9ebf-400b-ae91-20c71c647c19</uuid>
+  <memory unit='KiB'>131072</memory>
+  <currentMemory unit='KiB'>65536</currentMemory>
+  <vcpu placement='auto' current='2'>6</vcpu>
+  <cputune>
+    <emulatorpin cpuset='1-3'/>
+  </cputune>
+  <numatune>
+    <memory mode='strict' placement='auto'/>
+  </numatune>
+  <os>
+    <type arch='x86_64' machine='pc-q35-2.3'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-x86_64</emulator>
+    <controller type='sata' index='0'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
+    </controller>
+    <controller type='pci' index='0' model='pcie-root'/>
+    <controller type='pci' index='1' model='dmi-to-pci-bridge'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x1e' function='0x0'/>
+    </controller>
+    <controller type='pci' index='2' model='pci-bridge'>
+      <address type='pci' domain='0x0000' bus='0x01' slot='0x01' function='0x0'/>
+    </controller>
+    <memballoon model='none'/>
+  </devices>
+</domain>
diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-cputune-numatune.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-cputune-numatune.xml
new file mode 100644
index 0000000..b33f57f
--- /dev/null
+++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-cputune-numatune.xml
@@ -0,0 +1,32 @@
+<domain type='kvm'>
+  <name>dummy2</name>
+  <uuid>4d92ec27-9ebf-400b-ae91-20c71c647c19</uuid>
+  <memory unit='KiB'>131072</memory>
+  <currentMemory unit='KiB'>65536</currentMemory>
+  <vcpu placement='auto' current='2'>6</vcpu>
+  <numatune>
+    <memory mode='strict' placement='auto'/>
+  </numatune>
+  <os>
+    <type arch='x86_64' machine='pc-q35-2.3'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-x86_64</emulator>
+    <controller type='sata' index='0'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
+    </controller>
+    <controller type='pci' index='0' model='pcie-root'/>
+    <controller type='pci' index='1' model='dmi-to-pci-bridge'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x1e' function='0x0'/>
+    </controller>
+    <controller type='pci' index='2' model='pci-bridge'>
+      <address type='pci' domain='0x0000' bus='0x01' slot='0x01' function='0x0'/>
+    </controller>
+    <memballoon model='none'/>
+  </devices>
+</domain>
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 4abb303..9ceda58 100644
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -310,6 +310,7 @@ mymain(void)
     DO_TEST("blkiotune-device");
     DO_TEST("cputune");
     DO_TEST("cputune-zero-shares");
+    DO_TEST_DIFFERENT("cputune-numatune");
 
     DO_TEST("smp");
     DO_TEST("iothreads");
-- 
2.0.5