7:30 a.m.
If we don't properly clean up all processes in the
machine-<vmname>.scope systemd won't remove the cgroup and subsequent vm
starts fail with
'CreateMachine: File exists'
Additional processes can e.g. be added via
echo $PID > /sys/fs/cgroup/systemd/machine.slice/machine-${VMNAME}.scope/tasks
but there are other cases like
http://bugs.debian.org/761521
Invoke TerminateMachine to be on the safe side since systemd tracks the
cgroup anyway. This is a noop if all processes have terminated already.
---
src/libvirt_private.syms | 1 +
src/qemu/qemu_cgroup.c | 11 ++++++++++-
src/qemu/qemu_cgroup.h | 2 +-
src/qemu/qemu_process.c | 4 ++--
src/util/vircgroup.c | 11 +++++++++++
src/util/vircgroup.h | 5 +++++
6 files changed, 30 insertions(+), 4 deletions(-)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 51a692b..99ef1db 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1115,6 +1115,7 @@ virCgroupSetMemorySoftLimit;
virCgroupSetMemSwapHardLimit;
virCgroupSetOwner;
virCgroupSupportsCpuBW;
+virCgroupTerminateMachine;
# util/virclosecallbacks.h
diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c
index 7c6b2c1..0ab7227 100644
--- a/src/qemu/qemu_cgroup.c
+++ b/src/qemu/qemu_cgroup.c
@@ -1188,13 +1188,22 @@ qemuSetupCgroupForIOThreads(virDomainObjPtr vm)
}
int
-qemuRemoveCgroup(virDomainObjPtr vm)
+qemuRemoveCgroup(virQEMUDriverPtr driver,
+ virDomainObjPtr vm)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
+ virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
if (priv->cgroup == NULL)
return 0; /* Not supported, so claim success */
+ if (virCgroupTerminateMachine(vm->def->name,
+ "qemu",
+ cfg->privileged) < 0) {
+ if (!virCgroupNewIgnoreError())
+ VIR_DEBUG("Failed to terminate cgroup for %s",
vm->def->name);
+ }
+
return virCgroupRemove(priv->cgroup);
}
diff --git a/src/qemu/qemu_cgroup.h b/src/qemu/qemu_cgroup.h
index 8a2c723..4a4f22c 100644
--- a/src/qemu/qemu_cgroup.h
+++ b/src/qemu/qemu_cgroup.h
@@ -66,7 +66,7 @@ int qemuSetupCgroupForIOThreads(virDomainObjPtr vm);
int qemuSetupCgroupForEmulator(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virBitmapPtr nodemask);
-int qemuRemoveCgroup(virDomainObjPtr vm);
+int qemuRemoveCgroup(virQEMUDriverPtr driver, virDomainObjPtr vm);
int qemuAddToCgroup(virDomainObjPtr vm);
#endif /* __QEMU_CGROUP_H__ */
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 13614e9..e7cce1a 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -4131,7 +4131,7 @@ int qemuProcessStart(virConnectPtr conn,
/* Ensure no historical cgroup for this VM is lying around bogus
* settings */
VIR_DEBUG("Ensuring no historical cgroup is lying around");
- qemuRemoveCgroup(vm);
+ qemuRemoveCgroup(driver, vm);
for (i = 0; i < vm->def->ngraphics; ++i) {
virDomainGraphicsDefPtr graphics = vm->def->graphics[i];
@@ -4909,7 +4909,7 @@ void qemuProcessStop(virQEMUDriverPtr driver,
}
retry:
- if ((ret = qemuRemoveCgroup(vm)) < 0) {
+ if ((ret = qemuRemoveCgroup(driver, vm)) < 0) {
if (ret == -EBUSY && (retries++ < 5)) {
usleep(200*1000);
goto retry;
diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c
index 1dbe6f9..d69f71b 100644
--- a/src/util/vircgroup.c
+++ b/src/util/vircgroup.c
@@ -1680,6 +1680,17 @@ virCgroupNewMachineSystemd(const char *name,
}
+/*
+ * Returns 0 on success, -1 on fatal error
+ */
+int virCgroupTerminateMachine(const char *name,
+ const char *drivername,
+ bool privileged)
+{
+ return virSystemdTerminateMachine(name, drivername, privileged);
+}
+
+
static int
virCgroupNewMachineManual(const char *name,
const char *drivername,
diff --git a/src/util/vircgroup.h b/src/util/vircgroup.h
index 19e82d1..7718a07 100644
--- a/src/util/vircgroup.h
+++ b/src/util/vircgroup.h
@@ -106,6 +106,11 @@ int virCgroupNewMachine(const char *name,
ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2)
ATTRIBUTE_NONNULL(4);
+int virCgroupTerminateMachine(const char *name,
+ const char *drivername,
+ bool privileged)
+ ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2);
+
bool virCgroupNewIgnoreError(void);
void virCgroupFree(virCgroupPtr *group);
--
2.1.0