diff options
| -rw-r--r-- | include/linux/cgroup.h | 11 | ||||
| -rw-r--r-- | kernel/cgroup.c | 38 |
2 files changed, 24 insertions, 25 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index fd538f4c2bb6..cf8ba26b7c6e 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -68,6 +68,10 @@ struct cgroup_subsys_state { /* PI: the parent css */ struct cgroup_subsys_state *parent; + /* siblings list anchored at the parent's ->children */ + struct list_head sibling; + struct list_head children; + /* * PI: Subsys-unique ID. 0 is unused and root is always 1. The * matching css can be looked up using css_from_id(). @@ -171,13 +175,6 @@ struct cgroup { */ int populated_cnt; - /* - * We link our 'sibling' struct into our parent's 'children'. - * Our children link their 'sibling' into our 'children'. - */ - struct list_head sibling; /* my parent's children */ - struct list_head children; /* my children */ - struct kernfs_node *kn; /* cgroup kernfs entry */ struct kernfs_node *populated_kn; /* kn for "cgroup.subtree_populated" */ diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 8c67a739aea4..5385839e727b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -378,7 +378,7 @@ static int notify_on_release(const struct cgroup *cgrp) /* iterate over child cgrps, lock should be held throughout iteration */ #define cgroup_for_each_live_child(child, cgrp) \ - list_for_each_entry((child), &(cgrp)->children, sibling) \ + list_for_each_entry((child), &(cgrp)->self.children, self.sibling) \ if (({ lockdep_assert_held(&cgroup_mutex); \ cgroup_is_dead(child); })) \ ; \ @@ -870,7 +870,7 @@ static void cgroup_destroy_root(struct cgroup_root *root) mutex_lock(&cgroup_mutex); BUG_ON(atomic_read(&root->nr_cgrps)); - BUG_ON(!list_empty(&cgrp->children)); + BUG_ON(!list_empty(&cgrp->self.children)); /* Rebind all subsystems back to the default hierarchy */ rebind_subsystems(&cgrp_dfl_root, root->subsys_mask); @@ -1432,7 +1432,7 @@ static int cgroup_remount(struct kernfs_root *kf_root, int *flags, char *data) } /* remounting is not allowed for populated hierarchies */ - if (!list_empty(&root->cgrp.children)) { + if (!list_empty(&root->cgrp.self.children)) { ret = -EBUSY; goto out_unlock; } @@ -1512,8 +1512,8 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) struct cgroup_subsys *ss; int ssid; - INIT_LIST_HEAD(&cgrp->sibling); - INIT_LIST_HEAD(&cgrp->children); + INIT_LIST_HEAD(&cgrp->self.sibling); + INIT_LIST_HEAD(&cgrp->self.children); INIT_LIST_HEAD(&cgrp->cset_links); INIT_LIST_HEAD(&cgrp->release_list); INIT_LIST_HEAD(&cgrp->pidlists); @@ -1612,7 +1612,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned int ss_mask) link_css_set(&tmp_links, cset, root_cgrp); up_write(&css_set_rwsem); - BUG_ON(!list_empty(&root_cgrp->children)); + BUG_ON(!list_empty(&root_cgrp->self.children)); BUG_ON(atomic_read(&root->nr_cgrps) != 1); kernfs_activate(root_cgrp->kn); @@ -3128,11 +3128,11 @@ css_next_child(struct cgroup_subsys_state *pos_css, * cgroup is removed or iteration and removal race. */ if (!pos) { - next = list_entry_rcu(cgrp->children.next, struct cgroup, sibling); + next = list_entry_rcu(cgrp->self.children.next, struct cgroup, self.sibling); } else if (likely(!cgroup_is_dead(pos))) { - next = list_entry_rcu(pos->sibling.next, struct cgroup, sibling); + next = list_entry_rcu(pos->self.sibling.next, struct cgroup, self.sibling); } else { - list_for_each_entry_rcu(next, &cgrp->children, sibling) + list_for_each_entry_rcu(next, &cgrp->self.children, self.sibling) if (next->serial_nr > pos->serial_nr) break; } @@ -3142,12 +3142,12 @@ css_next_child(struct cgroup_subsys_state *pos_css, * the next sibling; however, it might have @ss disabled. If so, * fast-forward to the next enabled one. */ - while (&next->sibling != &cgrp->children) { + while (&next->self.sibling != &cgrp->self.children) { struct cgroup_subsys_state *next_css = cgroup_css(next, parent_css->ss); if (next_css) return next_css; - next = list_entry_rcu(next->sibling.next, struct cgroup, sibling); + next = list_entry_rcu(next->self.sibling.next, struct cgroup, self.sibling); } return NULL; } @@ -3283,7 +3283,7 @@ static bool cgroup_has_live_children(struct cgroup *cgrp) struct cgroup *child; rcu_read_lock(); - list_for_each_entry_rcu(child, &cgrp->children, sibling) { + list_for_each_entry_rcu(child, &cgrp->self.children, self.sibling) { if (!cgroup_is_dead(child)) { rcu_read_unlock(); return true; @@ -4144,7 +4144,7 @@ static void css_release_work_fn(struct work_struct *work) } else { /* cgroup release path */ mutex_lock(&cgroup_mutex); - list_del_rcu(&cgrp->sibling); + list_del_rcu(&cgrp->self.sibling); mutex_unlock(&cgroup_mutex); cgroup_idr_remove(&cgrp->root->cgroup_idr, cgrp->id); @@ -4168,9 +4168,11 @@ static void init_and_link_css(struct cgroup_subsys_state *css, { cgroup_get(cgrp); + memset(css, 0, sizeof(*css)); css->cgroup = cgrp; css->ss = ss; - css->flags = 0; + INIT_LIST_HEAD(&css->sibling); + INIT_LIST_HEAD(&css->children); if (cgroup_parent(cgrp)) { css->parent = cgroup_css(cgroup_parent(cgrp), ss); @@ -4344,7 +4346,7 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, cgrp->serial_nr = cgroup_serial_nr_next++; /* allocation complete, commit to creation */ - list_add_tail_rcu(&cgrp->sibling, &cgroup_parent(cgrp)->children); + list_add_tail_rcu(&cgrp->self.sibling, &cgroup_parent(cgrp)->self.children); atomic_inc(&root->nr_cgrps); cgroup_get(parent); @@ -4507,9 +4509,9 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) return -EBUSY; /* - * Make sure there's no live children. We can't test ->children - * emptiness as dead children linger on it while being destroyed; - * otherwise, "rmdir parent/child parent" may fail with -EBUSY. + * Make sure there's no live children. We can't test emptiness of + * ->self.children as dead children linger on it while being + * drained; otherwise, "rmdir parent/child parent" may fail. */ if (cgroup_has_live_children(cgrp)) return -EBUSY; |