3:27 p.m.
Not yet merged in upstream QEMU:
https://lists.gnu.org/archive/html/qemu-devel/2014-04/msg05024.html
Add support for invariant TSC timer running at constant rate in
all ACPI P-, C- and T-states.
It can be enabled by specifying:
<clock>
<timer name='invtsc' present='yes'/>
</clock>
in the domain XML.
Migration and saving the domain does not work with this timer.
The support for this timer is indicated by bit 8 of EDX after calling
CPUID with 0x80000007. It does not show up in /proc/cpuinfo [1]
and since we're calling qemu without 'enforce', it doesn't error
out if the host doesn't support this.
Alternatively, we could expose it in libvirt as a cpu flag:
<cpu mode='custom' match='exact'>
<model fallback='forbid'>qemu64</model>
<feature policy='require' name='invtsc'/>
</cpu>
or maybe add +invtsc to qemu args when the 'nonstop_tsc' flag is
requested?
[1]:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch...
---
docs/formatdomain.html.in | 9 ++++++--
docs/schemas/domaincommon.rng | 1 +
src/conf/domain_conf.c | 6 +++--
src/conf/domain_conf.h | 1 +
src/qemu/qemu_command.c | 6 +++++
src/qemu/qemu_migration.c | 14 ++++++++++++
.../qemuxml2argv-clock-timer-inv-tsc.args | 5 +++++
.../qemuxml2argv-clock-timer-inv-tsc.xml | 26 ++++++++++++++++++++++
tests/qemuxml2argvtest.c | 1 +
tests/qemuxml2xmltest.c | 1 +
10 files changed, 66 insertions(+), 4 deletions(-)
create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.args
create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.xml
diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 4f19473..1d3fd93 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -1368,13 +1368,18 @@
being modified, and can be one of
"platform" (currently unsupported),
"hpet" (libxl, xen, qemu), "kvmclock" (qemu),
- "pit" (qemu), "rtc" (qemu), "tsc" (libxl) or
"hypervclock"
- (qemu - <span class="since">since 1.2.2</span>).
+ "pit" (qemu), "rtc" (qemu), "tsc" (libxl),
"hypervclock"
+ (qemu - <span class="since">since 1.2.2</span>) or
+ "invtsc" (qemu - <span class="since">since
1.2.5</span>).
The <code>hypervclock</code> timer adds support for the
reference time counter and the reference page for iTSC
feature for guests running the Microsoft Windows
operating system.
+
+ The <code>invtsc</code> timer adds support for the invariant
+ TSC. It runs at a constant rate in all ACPI P- C- and T-states.
+ A guest with this timer enabled cannot be migrated or saved.
</dd>
<dt><code>track</code></dt>
<dd>
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 4249ed5..5154826 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -918,6 +918,7 @@
<choice>
<value>kvmclock</value>
<value>hypervclock</value>
+ <value>invtsc</value>
</choice>
</attribute>
</group>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 6c3bdad..893d904 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -706,7 +706,8 @@ VIR_ENUM_IMPL(virDomainTimerName, VIR_DOMAIN_TIMER_NAME_LAST,
"hpet",
"tsc",
"kvmclock",
- "hypervclock");
+ "hypervclock",
+ "invtsc");
VIR_ENUM_IMPL(virDomainTimerTrack, VIR_DOMAIN_TIMER_TRACK_LAST,
"boot",
@@ -2931,7 +2932,8 @@ virDomainDefPostParseInternal(virDomainDefPtr def,
virDomainTimerDefPtr timer = def->clock.timers[i];
if (timer->name == VIR_DOMAIN_TIMER_NAME_KVMCLOCK ||
- timer->name == VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK) {
+ timer->name == VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK ||
+ timer->name == VIR_DOMAIN_TIMER_NAME_INVTSC) {
if (timer->tickpolicy != -1) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("timer %s doesn't support setting of "
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index a92f0f3..53c02e6 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1635,6 +1635,7 @@ enum virDomainTimerNameType {
VIR_DOMAIN_TIMER_NAME_TSC,
VIR_DOMAIN_TIMER_NAME_KVMCLOCK,
VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK,
+ VIR_DOMAIN_TIMER_NAME_INVTSC,
VIR_DOMAIN_TIMER_NAME_LAST
};
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 6c1e17d..2994427 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -6736,6 +6736,11 @@ qemuBuildCpuArgStr(virQEMUDriverPtr driver,
have_cpu ? "" : default_model,
timer->present ? '+' : '-');
have_cpu = true;
+ } else if (timer->name == VIR_DOMAIN_TIMER_NAME_INVTSC) {
+ virBufferAsprintf(&buf, "%s,%cinvtsc",
+ have_cpu ? "" : default_model,
+ timer->present ? '+' : '-');
+ have_cpu = true;
} else if (timer->name == VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK &&
timer->present) {
virBufferAsprintf(&buf, "%s,hv_time",
@@ -8063,6 +8068,7 @@ qemuBuildCommandLine(virConnectPtr conn,
case VIR_DOMAIN_TIMER_NAME_KVMCLOCK:
case VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK:
+ case VIR_DOMAIN_TIMER_NAME_INVTSC:
/* Timers above are handled when building -cpu. */
case VIR_DOMAIN_TIMER_NAME_LAST:
break;
diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index a9f7fea..c1ffc0f 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -1513,6 +1513,20 @@ qemuMigrationIsAllowed(virQEMUDriverPtr driver, virDomainObjPtr
vm,
return false;
}
+ for (i = 0; i < def->clock.ntimers; i++) {
+ virDomainTimerDefPtr timer = def->clock.timers[i];
+
+ if (timer->present != 1)
+ continue;
+
+ if (timer->name == VIR_DOMAIN_TIMER_NAME_INVTSC) {
+ virReportError(VIR_ERR_OPERATION_INVALID,
+ _("domain has '%s' timer"),
+ virDomainTimerNameTypeToString(timer->name));
+ return false;
+ }
+ }
+
return true;
}
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.args
b/tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.args
new file mode 100644
index 0000000..ae74ae8
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.args
@@ -0,0 +1,5 @@
+LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
+/usr/bin/kvm -S -M pc \
+-cpu qemu32,+invtsc -m 214 -smp 6 \
+-nographic -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot n -usb -net \
+none -serial none -parallel none
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.xml
b/tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.xml
new file mode 100644
index 0000000..b4a82e8
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-clock-timer-inv-tsc.xml
@@ -0,0 +1,26 @@
+<domain type='kvm'>
+ <name>QEMUGuest1</name>
+ <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+ <memory unit='KiB'>219100</memory>
+ <currentMemory unit='KiB'>219100</currentMemory>
+ <vcpu placement='static'>6</vcpu>
+ <os>
+ <type arch='i686' machine='pc'>hvm</type>
+ <boot dev='network'/>
+ </os>
+ <features>
+ <pae/>
+ </features>
+ <clock offset='utc'>
+ <timer name='invtsc' present='yes'/>
+ </clock>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/kvm</emulator>
+ <controller type='usb' index='0'/>
+ <controller type='pci' index='0' model='pci-root'/>
+ <memballoon model='virtio'/>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 14482fd..3c5024e 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -641,6 +641,7 @@ mymain(void)
DO_TEST("cpu-host-kvmclock", QEMU_CAPS_ENABLE_KVM, QEMU_CAPS_CPU_HOST);
DO_TEST("kvmclock", QEMU_CAPS_KVM);
DO_TEST("clock-timer-hyperv-rtc", QEMU_CAPS_KVM);
+ DO_TEST("clock-timer-inv-tsc", QEMU_CAPS_KVM);
DO_TEST("cpu-eoi-disabled", QEMU_CAPS_ENABLE_KVM);
DO_TEST("cpu-eoi-enabled", QEMU_CAPS_ENABLE_KVM);
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 3ea03e6..a659cd0 100644
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -185,6 +185,7 @@ mymain(void)
DO_TEST("clock-catchup");
DO_TEST("kvmclock");
DO_TEST("clock-timer-hyperv-rtc");
+ DO_TEST("clock-timer-inv-tsc");
DO_TEST("cpu-eoi-disabled");
DO_TEST("cpu-eoi-enabled");
--
1.8.3.2