@@ -354,15 +354,8 @@ struct cgroup {
unsigned long flags; /* "unsigned long" so bitops work */
- /*
- * idr allocated in-hierarchy 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.
- */
- int id;
+ /* in-hierarchy ID allocated from kernfs */
+ u64 id;
/*
* The depth this cgroup is at. The root is at depth zero and each
@@ -488,7 +481,7 @@ struct cgroup {
struct cgroup_freezer_state freezer;
/* ids of the ancestors at each level including self */
- int ancestor_ids[];
+ u64 ancestor_ids[];
};
/*
@@ -509,7 +502,7 @@ struct cgroup_root {
struct cgroup cgrp;
/* for cgrp->ancestor_ids[0] */
- int cgrp_ancestor_id_storage;
+ u64 cgrp_ancestor_id_storage;
/* Number of cgroups in the hierarchy, used only for /proc/cgroups */
atomic_t nr_cgrps;
@@ -520,9 +513,6 @@ struct cgroup_root {
/* Hierarchy-specific flags */
unsigned int flags;
- /* IDs for cgroups in this hierarchy */
- struct idr cgroup_idr;
-
/* The path to use for release notifications. */
char release_agent_path[PATH_MAX];
@@ -15,14 +15,14 @@
#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
struct netprio_map {
struct rcu_head rcu;
- u32 priomap_len;
+ u64 priomap_len;
u32 priomap[];
};
-static inline u32 task_netprioidx(struct task_struct *p)
+static inline u64 task_netprioidx(struct task_struct *p)
{
struct cgroup_subsys_state *css;
- u32 idx;
+ u64 idx;
rcu_read_lock();
css = task_css(p, net_prio_cgrp_id);
@@ -41,7 +41,7 @@ static inline void sock_update_netprioidx(struct sock_cgroup_data *skcd)
#else /* !CONFIG_CGROUP_NET_PRIO */
-static inline u32 task_netprioidx(struct task_struct *p)
+static inline u64 task_netprioidx(struct task_struct *p)
{
return 0;
}
@@ -1308,10 +1308,7 @@ static void cgroup_exit_root_id(struct cgroup_root *root)
void cgroup_free_root(struct cgroup_root *root)
{
- if (root) {
- idr_destroy(&root->cgroup_idr);
- kfree(root);
- }
+ kfree(root);
}
static void cgroup_destroy_root(struct cgroup_root *root)
@@ -1917,7 +1914,6 @@ void init_cgroup_root(struct cgroup_fs_context *ctx)
atomic_set(&root->nr_cgrps, 1);
cgrp->root = root;
init_cgroup_housekeeping(cgrp);
- idr_init(&root->cgroup_idr);
root->flags = ctx->flags;
if (ctx->release_agent)
@@ -1938,12 +1934,6 @@ int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask)
lockdep_assert_held(&cgroup_mutex);
- ret = cgroup_idr_alloc(&root->cgroup_idr, root_cgrp, 1, 2, GFP_KERNEL);
- if (ret < 0)
- goto out;
- root_cgrp->id = ret;
- root_cgrp->ancestor_ids[0] = ret;
-
ret = percpu_ref_init(&root_cgrp->self.refcnt, css_release,
0, GFP_KERNEL);
if (ret)
@@ -1976,6 +1966,8 @@ int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask)
goto exit_root_id;
}
root_cgrp->kn = root->kf_root->kn;
+ root_cgrp->id = root_cgrp->kn->id;
+ root_cgrp->ancestor_ids[0] = root_cgrp->id;
ret = css_populate_dir(&root_cgrp->self);
if (ret)
@@ -4987,9 +4979,6 @@ static void css_release_work_fn(struct work_struct *work)
tcgrp->nr_dying_descendants--;
spin_unlock_irq(&css_set_lock);
- cgroup_idr_remove(&cgrp->root->cgroup_idr, cgrp->id);
- cgrp->id = -1;
-
/*
* There are two control paths which try to determine
* cgroup from dentry without going through kernfs -
@@ -5154,10 +5143,12 @@ static struct cgroup_subsys_state *css_create(struct cgroup *cgrp,
* it isn't associated with its kernfs_node and doesn't have the control
* mask applied.
*/
-static struct cgroup *cgroup_create(struct cgroup *parent)
+static struct cgroup *cgroup_create(struct cgroup *parent, const char *name,
+ umode_t mode)
{
struct cgroup_root *root = parent->root;
struct cgroup *cgrp, *tcgrp;
+ struct kernfs_node *kn;
int level = parent->level + 1;
int ret;
@@ -5177,15 +5168,14 @@ static struct cgroup *cgroup_create(struct cgroup *parent)
goto out_cancel_ref;
}
- /*
- * Temporarily set the pointer to NULL, so idr_find() won't return
- * a half-baked cgroup.
- */
- cgrp->id = cgroup_idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_KERNEL);
- if (cgrp->id < 0) {
- ret = -ENOMEM;
+ /* create the directory */
+ kn = kernfs_create_dir(parent->kn, name, mode, cgrp);
+ if (IS_ERR(kn)) {
+ ret = PTR_ERR(kn);
goto out_stat_exit;
}
+ cgrp->kn = kn;
+ cgrp->id = kn->id;
init_cgroup_housekeeping(cgrp);
@@ -5195,7 +5185,7 @@ static struct cgroup *cgroup_create(struct cgroup *parent)
ret = psi_cgroup_alloc(cgrp);
if (ret)
- goto out_idr_free;
+ goto out_kernfs_remove;
ret = cgroup_bpf_inherit(cgrp);
if (ret)
@@ -5248,12 +5238,6 @@ static struct cgroup *cgroup_create(struct cgroup *parent)
atomic_inc(&root->nr_cgrps);
cgroup_get_live(parent);
- /*
- * @cgrp is now fully operational. If something fails after this
- * point, it'll be released via the normal destruction path.
- */
- cgroup_idr_replace(&root->cgroup_idr, cgrp, cgrp->id);
-
/*
* On the default hierarchy, a child doesn't automatically inherit
* subtree_control from the parent. Each is configured manually.
@@ -5267,8 +5251,8 @@ static struct cgroup *cgroup_create(struct cgroup *parent)
out_psi_free:
psi_cgroup_free(cgrp);
-out_idr_free:
- cgroup_idr_remove(&root->cgroup_idr, cgrp->id);
+out_kernfs_remove:
+ kernfs_remove(cgrp->kn);
out_stat_exit:
if (cgroup_on_dfl(parent))
cgroup_rstat_exit(cgrp);
@@ -5305,7 +5289,6 @@ static bool cgroup_check_hierarchy_limits(struct cgroup *parent)
int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, umode_t mode)
{
struct cgroup *parent, *cgrp;
- struct kernfs_node *kn;
int ret;
/* do not accept '\n' to prevent making /proc/<pid>/cgroup unparsable */
@@ -5321,27 +5304,19 @@ int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, umode_t mode)
goto out_unlock;
}
- cgrp = cgroup_create(parent);
+ cgrp = cgroup_create(parent, name, mode);
if (IS_ERR(cgrp)) {
ret = PTR_ERR(cgrp);
goto out_unlock;
}
- /* create the directory */
- kn = kernfs_create_dir(parent->kn, name, mode, cgrp);
- if (IS_ERR(kn)) {
- ret = PTR_ERR(kn);
- goto out_destroy;
- }
- cgrp->kn = kn;
-
/*
* This extra ref will be put in cgroup_free_fn() and guarantees
* that @cgrp->kn is always accessible.
*/
- kernfs_get(kn);
+ kernfs_get(cgrp->kn);
- ret = cgroup_kn_set_ugid(kn);
+ ret = cgroup_kn_set_ugid(cgrp->kn);
if (ret)
goto out_destroy;
@@ -5356,7 +5331,7 @@ int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, umode_t mode)
TRACE_CGROUP_PATH(mkdir, cgrp);
/* let's create and online css's */
- kernfs_activate(kn);
+ kernfs_activate(cgrp->kn);
ret = 0;
goto out_unlock;
@@ -93,7 +93,7 @@ static int extend_netdev_table(struct net_device *dev, u32 target_idx)
static u32 netprio_prio(struct cgroup_subsys_state *css, struct net_device *dev)
{
struct netprio_map *map = rcu_dereference_rtnl(dev->priomap);
- int id = css->cgroup->id;
+ u64 id = css->cgroup->id;
if (map && id < map->priomap_len)
return map->priomap[id];
@@ -113,7 +113,7 @@ static int netprio_set_prio(struct cgroup_subsys_state *css,
struct net_device *dev, u32 prio)
{
struct netprio_map *map;
- int id = css->cgroup->id;
+ u64 id = css->cgroup->id;
int ret;
/* avoid extending priomap for zero writes */