diff options
| -rw-r--r-- | include/linux/cgroup.h | 20 | ||||
| -rw-r--r-- | kernel/cgroup.c | 22 |
2 files changed, 24 insertions, 18 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index c24bd0b9f93a..b685955d4b29 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -741,27 +741,11 @@ static inline struct cgroup *task_cgroup(struct task_struct *task, return task_css(task, subsys_id)->cgroup; } -/** - * cgroup_from_id - lookup cgroup by id - * @ss: cgroup subsys to be looked into - * @id: the cgroup id - * - * Returns the cgroup if there's valid one with @id, otherwise returns NULL. - * Should be called under rcu_read_lock(). - */ -static inline struct cgroup *cgroup_from_id(struct cgroup_subsys *ss, int id) -{ -#ifdef CONFIG_PROVE_RCU - rcu_lockdep_assert(rcu_read_lock_held() || - lockdep_is_held(&cgroup_mutex), - "cgroup_from_id() needs proper protection"); -#endif - return idr_find(&ss->root->cgroup_idr, id); -} - struct cgroup_subsys_state *css_next_child(struct cgroup_subsys_state *pos, struct cgroup_subsys_state *parent); +struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss); + /** * css_for_each_child - iterate through children of a css * @pos: the css * to use as the loop cursor diff --git a/kernel/cgroup.c b/kernel/cgroup.c index b69b572131e5..ff7d642a070a 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -5717,6 +5717,28 @@ struct cgroup_subsys_state *cgroup_css_from_dir(struct file *f, int id) return css ? css : ERR_PTR(-ENOENT); } +/** + * css_from_id - lookup css by id + * @id: the cgroup id + * @ss: cgroup subsys to be looked into + * + * Returns the css if there's valid one with @id, otherwise returns NULL. + * Should be called under rcu_read_lock(). + */ +struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss) +{ + struct cgroup *cgrp; + + rcu_lockdep_assert(rcu_read_lock_held() || + lockdep_is_held(&cgroup_mutex), + "css_from_id() needs proper protection"); + + cgrp = idr_find(&ss->root->cgroup_idr, id); + if (cgrp) + return cgroup_css(cgrp, ss->subsys_id); + return NULL; +} + #ifdef CONFIG_CGROUP_DEBUG static struct cgroup_subsys_state * debug_css_alloc(struct cgroup_subsys_state *parent_css) |