Re: [libvirt] [PATCH v3 10/16] Add a new virCgroupNewPartition for setting up resource partitions

From: "Daniel P. Berrange" <berrange(a)redhat.com&gt; A resource partition is an absolute cgroup path, ignoring the current process placement. Expose a virCgroupNewPartition API for constructing such cgroups Signed-off-by: Daniel P. Berrange <berrange(a)redhat.com&gt; --- src/libvirt_private.syms | 4 +- src/lxc/lxc_cgroup.c | 2 +- src/qemu/qemu_cgroup.c | 2 +- src/util/vircgroup.c | 146 ++++++++++++++++++++++++++++++++++++++--- src/util/vircgroup.h | 20 ++++-- tests/vircgrouptest.c | 166 ++++++++++++++++++++++++++++++++++++++++++++++- 6 files changed, 321 insertions(+), 19 deletions(-)

diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c index bcc61a8..40e0fe6 100644 --- a/src/util/vircgroup.c +++ b/src/util/vircgroup.c @@ -1055,6 +1055,76 @@ cleanup: return rc; } + +#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R +/** + * virCgroupNewPartition: + * @path: path for the partition + * @create: true to create the cgroup tree + * @controllers: mask of controllers to create + * + * Creates a new cgroup to represent the resource + * partition path identified by @name. + * + * Returns 0 on success, -errno on failure + */ +int virCgroupNewPartition(const char *path, + bool create, + int controllers, + virCgroupPtr *group) +{ + int rc; + char *parentPath = NULL; + virCgroupPtr parent = NULL; + VIR_DEBUG("path=%s create=%d controllers=%x", + path, create, controllers); + + if (path[0] != '/') + return -EINVAL; + + rc = virCgroupNew(path, NULL, controllers, group); + if (rc != 0) + goto cleanup; + + if (STRNEQ(path, "/")) { + char *tmp; + if (!(parentPath = strdup(path))) + return -ENOMEM;

+ + tmp = strrchr(parentPath, '/'); + tmp++; + *tmp = '\0'; + + rc = virCgroupNew(parentPath, NULL, controllers, &parent); + if (rc != 0) + goto cleanup;

+ + rc = virCgroupMakeGroup(parent, *group, create, VIR_CGROUP_NONE); + if (rc != 0) { + virCgroupRemove(*group); + virCgroupFree(group); + goto cleanup; + } + } + +cleanup: + virCgroupFree(&parent); + VIR_FREE(parentPath); + return rc; +}