Add support for configuring libvirt VM clock and timers

There are a number of time sources made available to guests,
each of which have a number of configurable policies. This
introduces config APIs for the libvirt domain XML to configure
the clock time sources

Change-Id: Ic5047b02b4753f20bb9a63e85130d84258df7a28
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

2 files changed, 157 insertions, 0 deletions

diff --git a/nova/tests/test_libvirt_config.py b/nova/tests/test_libvirt_config.py
index df435690f..1e0818bd7 100644
--- a/nova/tests/test_libvirt_config.py
+++ b/nova/tests/test_libvirt_config.py
@@ -54,6 +54,98 @@ class LibvirtConfigTest(LibvirtConfigBaseTest):
         self.assertXmlEqual(xml, "<demo><foo>bar</foo></demo>")
 
 
+class LibvirtConfigGuestTimerTest(LibvirtConfigBaseTest):
+    def test_config_platform(self):
+        obj = config.LibvirtConfigGuestTimer()
+        obj.track = "host"
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <timer name="platform" track="host"/>
+        """)
+
+    def test_config_pit(self):
+        obj = config.LibvirtConfigGuestTimer()
+        obj.name = "pit"
+        obj.tickpolicy = "discard"
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <timer name="pit" tickpolicy="discard"/>
+        """)
+
+    def test_config_hpet(self):
+        obj = config.LibvirtConfigGuestTimer()
+        obj.name = "hpet"
+        obj.present = False
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <timer name="hpet" present="no"/>
+        """)
+
+
+class LibvirtConfigGuestClockTest(LibvirtConfigBaseTest):
+    def test_config_utc(self):
+        obj = config.LibvirtConfigGuestClock()
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <clock offset="utc"/>
+        """)
+
+    def test_config_localtime(self):
+        obj = config.LibvirtConfigGuestClock()
+        obj.offset = "localtime"
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <clock offset="localtime"/>
+        """)
+
+    def test_config_timezone(self):
+        obj = config.LibvirtConfigGuestClock()
+        obj.offset = "timezone"
+        obj.timezone = "EDT"
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <clock offset="timezone" timezone="EDT"/>
+        """)
+
+    def test_config_variable(self):
+        obj = config.LibvirtConfigGuestClock()
+        obj.offset = "variable"
+        obj.adjustment = "123456"
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <clock offset="variable" adjustment="123456"/>
+        """)
+
+    def test_config_timers(self):
+        obj = config.LibvirtConfigGuestClock()
+
+        tmpit = config.LibvirtConfigGuestTimer()
+        tmpit.name = "pit"
+        tmpit.tickpolicy = "discard"
+
+        tmrtc = config.LibvirtConfigGuestTimer()
+        tmrtc.name = "rtc"
+        tmrtc.tickpolicy = "merge"
+
+        obj.add_timer(tmpit)
+        obj.add_timer(tmrtc)
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+            <clock offset="utc">
+               <timer name="pit" tickpolicy="discard"/>
+               <timer name="rtc" tickpolicy="merge"/>
+            </clock>
+        """)
+
+
 class LibvirtConfigGuestDiskTest(LibvirtConfigBaseTest):
 
     def test_config_file(self):
diff --git a/nova/virt/libvirt/config.py b/nova/virt/libvirt/config.py
index 3f068fa05..3ebdf21f0 100644
--- a/nova/virt/libvirt/config.py
+++ b/nova/virt/libvirt/config.py
@@ -63,6 +63,63 @@ class LibvirtConfigObject(object):
         return xml_str
 
 
+class LibvirtConfigGuestTimer(LibvirtConfigObject):
+
+    def __init__(self, **kwargs):
+        super(LibvirtConfigGuestTimer, self).__init__(root_name="timer",
+                                                      **kwargs)
+
+        self.name = "platform"
+        self.track = None
+        self.tickpolicy = None
+        self.present = None
+
+    def format_dom(self):
+        tm = super(LibvirtConfigGuestTimer, self).format_dom()
+
+        tm.set("name", self.name)
+        if self.track is not None:
+            tm.set("track", self.track)
+        if self.tickpolicy is not None:
+            tm.set("tickpolicy", self.tickpolicy)
+        if self.present is not None:
+            if self.present:
+                tm.set("present", "yes")
+            else:
+                tm.set("present", "no")
+
+        return tm
+
+
+class LibvirtConfigGuestClock(LibvirtConfigObject):
+
+    def __init__(self, **kwargs):
+        super(LibvirtConfigGuestClock, self).__init__(root_name="clock",
+                                                      **kwargs)
+
+        self.offset = "utc"
+        self.adjustment = None
+        self.timezone = None
+        self.timers = []
+
+    def format_dom(self):
+        clk = super(LibvirtConfigGuestClock, self).format_dom()
+
+        clk.set("offset", self.offset)
+        if self.adjustment:
+            clk.set("adjustment", self.adjustment)
+        elif self.timezone:
+            clk.set("timezone", self.timezone)
+
+        for tm in self.timers:
+            clk.append(tm.format_dom())
+
+        return clk
+
+    def add_timer(self, tm):
+        self.timers.append(tm)
+
+
 class LibvirtConfigGuestDevice(LibvirtConfigObject):
 
     def __init__(self, **kwargs):
@@ -306,6 +363,7 @@ class LibvirtConfigGuest(LibvirtConfigObject):
         self.memory = 1024 * 1024 * 500
         self.vcpus = 1
         self.acpi = False
+        self.clock = None
         self.os_type = None
         self.os_kernel = None
         self.os_initrd = None
@@ -360,6 +418,10 @@ class LibvirtConfigGuest(LibvirtConfigObject):
         self._format_basic_props(root)
         self._format_os(root)
         self._format_features(root)
+
+        if self.clock is not None:
+            root.append(self.clock.format_dom())
+
         self._format_devices(root)
 
         return root
@@ -367,6 +429,9 @@ class LibvirtConfigGuest(LibvirtConfigObject):
     def add_device(self, dev):
         self.devices.append(dev)
 
+    def set_clock(self, clk):
+        self.clock = clk
+
 
 class LibvirtConfigCPU(LibvirtConfigObject):