diff options
Diffstat (limited to 'include/linux/cgroup.h')
-rw-r--r-- | include/linux/cgroup.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 821678a..18112a3 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -647,6 +647,21 @@ struct cgroup_subsys { #undef SUBSYS /** + * css_parent - find the parent css + * @css: the target cgroup_subsys_state + * + * Return the parent css of @css. This function is guaranteed to return + * non-NULL parent as long as @css isn't the root. + */ +static inline +struct cgroup_subsys_state *css_parent(struct cgroup_subsys_state *css) +{ + struct cgroup *parent_cgrp = css->cgroup->parent; + + return parent_cgrp ? parent_cgrp->subsys[css->ss->subsys_id] : NULL; +} + +/** * cgroup_css - obtain a cgroup's css for the specified subsystem * @cgrp: the cgroup of interest * @subsys_id: the subsystem of interest |