diff options
Diffstat (limited to 'include/linux/cgroup.h')
| -rw-r--r-- | include/linux/cgroup.h | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 22e3754f89c5..b5ee2c4210f9 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -81,7 +81,6 @@ struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgroup, struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry, struct cgroup_subsys *ss); -bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor); int cgroup_attach_task_all(struct task_struct *from, struct task_struct *); int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from); @@ -459,6 +458,23 @@ static inline struct cgroup *task_cgroup(struct task_struct *task, return task_css(task, subsys_id)->cgroup; } +/** + * cgroup_is_descendant - test ancestry + * @cgrp: the cgroup to be tested + * @ancestor: possible ancestor of @cgrp + * + * Test whether @cgrp is a descendant of @ancestor. It also returns %true + * if @cgrp == @ancestor. This function is safe to call as long as @cgrp + * and @ancestor are accessible. + */ +static inline bool cgroup_is_descendant(struct cgroup *cgrp, + struct cgroup *ancestor) +{ + if (cgrp->root != ancestor->root || cgrp->level < ancestor->level) + return false; + return cgrp->ancestor_ids[ancestor->level] == ancestor->id; +} + /* no synchronization, the result can only be used as a hint */ static inline bool cgroup_is_populated(struct cgroup *cgrp) { |