diff options
| -rw-r--r-- | include/linux/cgroup.h | 9 | ||||
| -rw-r--r-- | kernel/cgroup/cgroup.c | 27 |
2 files changed, 34 insertions, 2 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 989c08b09691..7865b681731c 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -19,6 +19,7 @@ #include <linux/kernfs.h> #include <linux/jump_label.h> #include <linux/types.h> +#include <linux/notifier.h> #include <linux/ns_common.h> #include <linux/nsproxy.h> #include <linux/user_namespace.h> @@ -40,7 +41,7 @@ struct kernel_clone_args; #ifdef CONFIG_CGROUPS -enum { +enum css_task_iter_flags { CSS_TASK_ITER_PROCS = (1U << 0), /* walk only threadgroup leaders */ CSS_TASK_ITER_THREADED = (1U << 1), /* walk all threaded css_sets in the domain */ CSS_TASK_ITER_SKIPPED = (1U << 16), /* internal flags */ @@ -66,10 +67,16 @@ struct css_task_iter { struct list_head iters_node; /* css_set->task_iters */ }; +enum cgroup_lifetime_events { + CGROUP_LIFETIME_ONLINE, + CGROUP_LIFETIME_OFFLINE, +}; + extern struct file_system_type cgroup_fs_type; extern struct cgroup_root cgrp_dfl_root; extern struct css_set init_css_set; extern spinlock_t css_set_lock; +extern struct blocking_notifier_head cgroup_lifetime_notifier; #define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys; #include <linux/cgroup_subsys.h> diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 98a0c32ef98b..3e993db7e026 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -95,6 +95,9 @@ EXPORT_SYMBOL_GPL(cgroup_mutex); EXPORT_SYMBOL_GPL(css_set_lock); #endif +struct blocking_notifier_head cgroup_lifetime_notifier = + BLOCKING_NOTIFIER_INIT(cgroup_lifetime_notifier); + DEFINE_SPINLOCK(trace_cgroup_path_lock); char trace_cgroup_path[TRACE_CGROUP_PATH_LEN]; static bool cgroup_debug __read_mostly; @@ -1326,6 +1329,7 @@ static void cgroup_destroy_root(struct cgroup_root *root) { struct cgroup *cgrp = &root->cgrp; struct cgrp_cset_link *link, *tmp_link; + int ret; trace_cgroup_destroy_root(root); @@ -1334,6 +1338,10 @@ static void cgroup_destroy_root(struct cgroup_root *root) BUG_ON(atomic_read(&root->nr_cgrps)); BUG_ON(!list_empty(&cgrp->self.children)); + ret = blocking_notifier_call_chain(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_OFFLINE, cgrp); + WARN_ON_ONCE(notifier_to_errno(ret)); + /* Rebind all subsystems back to the default hierarchy */ WARN_ON(rebind_subsystems(&cgrp_dfl_root, root->subsys_mask)); @@ -2140,6 +2148,10 @@ int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask) WARN_ON_ONCE(ret); } + ret = blocking_notifier_call_chain(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_ONLINE, root_cgrp); + WARN_ON_ONCE(notifier_to_errno(ret)); + trace_cgroup_setup_root(root); /* @@ -5733,6 +5745,15 @@ static struct cgroup *cgroup_create(struct cgroup *parent, const char *name, goto out_psi_free; } + ret = blocking_notifier_call_chain_robust(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_ONLINE, + CGROUP_LIFETIME_OFFLINE, cgrp); + ret = notifier_to_errno(ret); + if (ret) { + cgroup_bpf_offline(cgrp); + goto out_psi_free; + } + /* allocation complete, commit to creation */ spin_lock_irq(&css_set_lock); for (i = 0; i < level; i++) { @@ -5966,7 +5987,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) struct cgroup *tcgrp, *parent = cgroup_parent(cgrp); struct cgroup_subsys_state *css; struct cgrp_cset_link *link; - int ssid; + int ssid, ret; lockdep_assert_held(&cgroup_mutex); @@ -6027,6 +6048,10 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) if (cgrp->root == &cgrp_dfl_root) cgroup_bpf_offline(cgrp); + ret = blocking_notifier_call_chain(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_OFFLINE, cgrp); + WARN_ON_ONCE(notifier_to_errno(ret)); + /* put the base reference */ percpu_ref_kill(&cgrp->self.refcnt); |