diff options
Diffstat (limited to 'kernel/cgroup.c')
| -rw-r--r-- | kernel/cgroup.c | 126 |
1 files changed, 98 insertions, 28 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 470f6536b9e8..fe95970b1f79 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -57,8 +57,8 @@ #include <linux/vmalloc.h> /* TODO: replace with more sophisticated array */ #include <linux/kthread.h> #include <linux/delay.h> - #include <linux/atomic.h> +#include <net/sock.h> /* * pidlists linger the following amount before being destroyed. The goal @@ -440,11 +440,6 @@ static bool cgroup_tryget(struct cgroup *cgrp) return css_tryget(&cgrp->self); } -static void cgroup_put(struct cgroup *cgrp) -{ - css_put(&cgrp->self); -} - struct cgroup_subsys_state *of_css(struct kernfs_open_file *of) { struct cgroup *cgrp = of->kn->parent->priv; @@ -465,25 +460,6 @@ struct cgroup_subsys_state *of_css(struct kernfs_open_file *of) } EXPORT_SYMBOL_GPL(of_css); -/** - * cgroup_is_descendant - test ancestry - * @cgrp: the cgroup to be tested - * @ancestor: possible ancestor of @cgrp - * - * Test whether @cgrp is a descendant of @ancestor. It also returns %true - * if @cgrp == @ancestor. This function is safe to call as long as @cgrp - * and @ancestor are accessible. - */ -bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor) -{ - while (cgrp) { - if (cgrp == ancestor) - return true; - cgrp = cgroup_parent(cgrp); - } - return false; -} - static int notify_on_release(const struct cgroup *cgrp) { return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags); @@ -1924,6 +1900,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask) 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); @@ -4903,11 +4880,11 @@ err_free_css: static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, umode_t mode) { - struct cgroup *parent, *cgrp; + struct cgroup *parent, *cgrp, *tcgrp; struct cgroup_root *root; struct cgroup_subsys *ss; struct kernfs_node *kn; - int ssid, ret; + int level, ssid, ret; /* Do not accept '\n' to prevent making /proc/<pid>/cgroup unparsable. */ @@ -4918,9 +4895,11 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, if (!parent) return -ENODEV; root = parent->root; + level = parent->level + 1; /* allocate the cgroup and its ID, 0 is reserved for the root */ - cgrp = kzalloc(sizeof(*cgrp), GFP_KERNEL); + cgrp = kzalloc(sizeof(*cgrp) + + sizeof(cgrp->ancestor_ids[0]) * (level + 1), GFP_KERNEL); if (!cgrp) { ret = -ENOMEM; goto out_unlock; @@ -4944,6 +4923,10 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, cgrp->self.parent = &parent->self; cgrp->root = root; + cgrp->level = level; + + for (tcgrp = cgrp; tcgrp; tcgrp = cgroup_parent(tcgrp)) + cgrp->ancestor_ids[tcgrp->level] = tcgrp->id; if (notify_on_release(parent)) set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags); @@ -5822,6 +5805,93 @@ struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss) return id > 0 ? idr_find(&ss->css_idr, id) : NULL; } +/** + * cgroup_get_from_path - lookup and get a cgroup from its default hierarchy path + * @path: path on the default hierarchy + * + * Find the cgroup at @path on the default hierarchy, increment its + * reference count and return it. Returns pointer to the found cgroup on + * success, ERR_PTR(-ENOENT) if @path doens't exist and ERR_PTR(-ENOTDIR) + * if @path points to a non-directory. + */ +struct cgroup *cgroup_get_from_path(const char *path) +{ + struct kernfs_node *kn; + struct cgroup *cgrp; + + mutex_lock(&cgroup_mutex); + + kn = kernfs_walk_and_get(cgrp_dfl_root.cgrp.kn, path); + if (kn) { + if (kernfs_type(kn) == KERNFS_DIR) { + cgrp = kn->priv; + cgroup_get(cgrp); + } else { + cgrp = ERR_PTR(-ENOTDIR); + } + kernfs_put(kn); + } else { + cgrp = ERR_PTR(-ENOENT); + } + + mutex_unlock(&cgroup_mutex); + return cgrp; +} +EXPORT_SYMBOL_GPL(cgroup_get_from_path); + +/* + * sock->sk_cgrp_data handling. For more info, see sock_cgroup_data + * definition in cgroup-defs.h. + */ +#ifdef CONFIG_SOCK_CGROUP_DATA + +#if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID) + +DEFINE_SPINLOCK(cgroup_sk_update_lock); +static bool cgroup_sk_alloc_disabled __read_mostly; + +void cgroup_sk_alloc_disable(void) +{ + if (cgroup_sk_alloc_disabled) + return; + pr_info("cgroup: disabling cgroup2 socket matching due to net_prio or net_cls activation\n"); + cgroup_sk_alloc_disabled = true; +} + +#else + +#define cgroup_sk_alloc_disabled false + +#endif + +void cgroup_sk_alloc(struct sock_cgroup_data *skcd) +{ + if (cgroup_sk_alloc_disabled) + return; + + rcu_read_lock(); + + while (true) { + struct css_set *cset; + + cset = task_css_set(current); + if (likely(cgroup_tryget(cset->dfl_cgrp))) { + skcd->val = (unsigned long)cset->dfl_cgrp; + break; + } + cpu_relax(); + } + + rcu_read_unlock(); +} + +void cgroup_sk_free(struct sock_cgroup_data *skcd) +{ + cgroup_put(sock_cgroup_ptr(skcd)); +} + +#endif /* CONFIG_SOCK_CGROUP_DATA */ + #ifdef CONFIG_CGROUP_DEBUG static struct cgroup_subsys_state * debug_css_alloc(struct cgroup_subsys_state *parent_css) |