diff options
| -rw-r--r-- | include/linux/cgroup.h | 4 | ||||
| -rw-r--r-- | kernel/cgroup.c | 4 | ||||
| -rw-r--r-- | mm/memcontrol.c | 8 |
3 files changed, 6 insertions, 10 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index c6c703f..793f70a 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -144,8 +144,8 @@ struct cgroup { /* * idr allocated in-hierarchy ID. * - * The ID of the root cgroup is always 0, and a new cgroup - * will be assigned with a smallest available ID. + * ID 0 is not used, the ID of the root cgroup is always 1, and a + * new cgroup will be assigned with a smallest available ID. * * Allocating/Removing ID must be protected by cgroup_mutex. */ diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 21667f3..3fa0463 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1531,7 +1531,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned int ss_mask) lockdep_assert_held(&cgroup_tree_mutex); lockdep_assert_held(&cgroup_mutex); - ret = idr_alloc(&root->cgroup_idr, root_cgrp, 0, 1, GFP_KERNEL); + ret = idr_alloc(&root->cgroup_idr, root_cgrp, 1, 2, GFP_KERNEL); if (ret < 0) goto out; root_cgrp->id = ret; @@ -4225,7 +4225,7 @@ static long cgroup_create(struct cgroup *parent, const char *name, * Temporarily set the pointer to NULL, so idr_find() won't return * a half-baked cgroup. */ - cgrp->id = idr_alloc(&root->cgroup_idr, NULL, 1, 0, GFP_KERNEL); + cgrp->id = idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_KERNEL); if (cgrp->id < 0) { err = -ENOMEM; goto err_unlock; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 29501f0..1d0b297 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -527,18 +527,14 @@ static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg) { - /* - * The ID of the root cgroup is 0, but memcg treat 0 as an - * invalid ID, so we return (cgroup_id + 1). - */ - return memcg->css.cgroup->id + 1; + return memcg->css.cgroup->id; } static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id) { struct cgroup_subsys_state *css; - css = css_from_id(id - 1, &memory_cgrp_subsys); + css = css_from_id(id, &memory_cgrp_subsys); return mem_cgroup_from_css(css); } |
