4:40 a.m.
Introduce the function virCgroupForVcpu() to create sub directory for each vcpu.
---
src/libvirt_private.syms | 1 +
src/util/cgroup.c | 72 ++++++++++++++++++++++++++++++++++++++++++---
src/util/cgroup.h | 5 +++
3 files changed, 73 insertions(+), 5 deletions(-)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 3e3b1dd..30804eb 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -67,6 +67,7 @@ virCgroupDenyAllDevices;
virCgroupDenyDevicePath;
virCgroupForDomain;
virCgroupForDriver;
+virCgroupForVcpu;
virCgroupFree;
virCgroupGetBlkioWeight;
virCgroupGetCpuShares;
diff --git a/src/util/cgroup.c b/src/util/cgroup.c
index 740cedf..8994aca 100644
--- a/src/util/cgroup.c
+++ b/src/util/cgroup.c
@@ -52,6 +52,16 @@ struct virCgroup {
struct virCgroupController controllers[VIR_CGROUP_CONTROLLER_LAST];
};
+typedef enum {
+ VIR_CGROUP_NONE = 0, /* create subdir under each cgroup if possible. */
+ VIR_CGROUP_MEM_HIERACHY = 1 << 0, /* call virCgroupSetMemoryUseHierarchy
+ * before creating subcgroups and
+ * attaching tasks
+ */
+ VIR_CGROUP_VCPU = 1 << 1, /* create subdir only under the cgroup cpu,
+ * cpuacct and cpuset if possible. */
+} virCgroupFlags;
+
/**
* virCgroupFree:
*
@@ -503,7 +513,7 @@ static int virCgroupSetMemoryUseHierarchy(virCgroupPtr group)
}
static int virCgroupMakeGroup(virCgroupPtr parent, virCgroupPtr group,
- int create, bool memory_hierarchy)
+ int create, unsigned int flags)
{
int i;
int rc = 0;
@@ -516,6 +526,13 @@ static int virCgroupMakeGroup(virCgroupPtr parent, virCgroupPtr
group,
if (!group->controllers[i].mountPoint)
continue;
+ /* We need to control cpu bandwidth for each vcpu now */
+ if ((flags & VIR_CGROUP_VCPU) && i != VIR_CGROUP_CONTROLLER_CPU) {
+ /* treat it as unmounted and we can use virCgroupAddTask */
+ VIR_FREE(group->controllers[i].mountPoint);
+ continue;
+ }
+
rc = virCgroupPathOfController(group, i, "", &path);
if (rc < 0)
return rc;
@@ -555,7 +572,7 @@ static int virCgroupMakeGroup(virCgroupPtr parent, virCgroupPtr
group,
* Note that virCgroupSetMemoryUseHierarchy should always be
* called prior to creating subcgroups and attaching tasks.
*/
- if (memory_hierarchy &&
+ if ((flags & VIR_CGROUP_MEM_HIERACHY) &&
group->controllers[VIR_CGROUP_CONTROLLER_MEMORY].mountPoint != NULL
&&
(i == VIR_CGROUP_CONTROLLER_MEMORY ||
STREQ(group->controllers[i].mountPoint,
group->controllers[VIR_CGROUP_CONTROLLER_MEMORY].mountPoint))) {
@@ -641,7 +658,7 @@ static int virCgroupAppRoot(int privileged,
if (rc != 0)
goto cleanup;
- rc = virCgroupMakeGroup(rootgrp, *group, create, false);
+ rc = virCgroupMakeGroup(rootgrp, *group, create, VIR_CGROUP_NONE);
cleanup:
virCgroupFree(&rootgrp);
@@ -801,7 +818,7 @@ int virCgroupForDriver(const char *name,
VIR_FREE(path);
if (rc == 0) {
- rc = virCgroupMakeGroup(rootgrp, *group, create, false);
+ rc = virCgroupMakeGroup(rootgrp, *group, create, VIR_CGROUP_NONE);
if (rc != 0)
virCgroupFree(group);
}
@@ -861,7 +878,7 @@ int virCgroupForDomain(virCgroupPtr driver,
* a group for driver, is to avoid overhead to track
* cumulative usage that we don't need.
*/
- rc = virCgroupMakeGroup(driver, *group, create, true);
+ rc = virCgroupMakeGroup(driver, *group, create, VIR_CGROUP_MEM_HIERACHY);
if (rc != 0)
virCgroupFree(group);
}
@@ -879,6 +896,51 @@ int virCgroupForDomain(virCgroupPtr driver ATTRIBUTE_UNUSED,
#endif
/**
+ * virCgroupForVcpu:
+ *
+ * @driver: group for the domain
+ * @vcpuid: id of the vcpu
+ * @group: Pointer to returned virCgroupPtr
+ *
+ * Returns 0 on success
+ */
+#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
+int virCgroupForVcpu(virCgroupPtr driver,
+ int vcpuid,
+ virCgroupPtr *group,
+ int create)
+{
+ int rc;
+ char *path;
+
+ if (driver == NULL)
+ return -EINVAL;
+
+ if (virAsprintf(&path, "%s/vcpu%d", driver->path, vcpuid) < 0)
+ return -ENOMEM;
+
+ rc = virCgroupNew(path, group);
+ VIR_FREE(path);
+
+ if (rc == 0) {
+ rc = virCgroupMakeGroup(driver, *group, create, VIR_CGROUP_VCPU);
+ if (rc != 0)
+ virCgroupFree(group);
+ }
+
+ return rc;
+}
+#else
+int virCgroupForVcpu(virCgroupPtr driver ATTRIBUTE_UNUSED,
+ int vcpuid ATTRIBUTE_UNUSED,
+ virCgroupPtr *group ATTRIBUTE_UNUSED,
+ int create ATTRIBUTE_UNUSED)
+{
+ return -ENXIO;
+}
+#endif
+
+/**
* virCgroupSetBlkioWeight:
*
* @group: The cgroup to change io weight for
diff --git a/src/util/cgroup.h b/src/util/cgroup.h
index 8ae756d..1d04418 100644
--- a/src/util/cgroup.h
+++ b/src/util/cgroup.h
@@ -40,6 +40,11 @@ int virCgroupForDomain(virCgroupPtr driver,
virCgroupPtr *group,
int create);
+int virCgroupForVcpu(virCgroupPtr driver,
+ int vcpuid,
+ virCgroupPtr *group,
+ int create);
+
int virCgroupPathOfController(virCgroupPtr group,
int controller,
const char *key,
--
1.7.1