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Diffstat (limited to 'kernel/cgroup.c')
-rw-r--r--kernel/cgroup.c54
1 files changed, 41 insertions, 13 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b24d7027b83c..95362d15128c 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4230,20 +4230,8 @@ void cgroup_post_fork(struct task_struct *child)
*/
void cgroup_exit(struct task_struct *tsk, int run_callbacks)
{
- int i;
struct css_set *cg;
-
- if (run_callbacks && need_forkexit_callback) {
- /*
- * modular subsystems can't use callbacks, so no need to lock
- * the subsys array
- */
- for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
- struct cgroup_subsys *ss = subsys[i];
- if (ss->exit)
- ss->exit(ss, tsk);
- }
- }
+ int i;
/*
* Unlink from the css_set task list if necessary.
@@ -4261,7 +4249,24 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
task_lock(tsk);
cg = tsk->cgroups;
tsk->cgroups = &init_css_set;
+
+ if (run_callbacks && need_forkexit_callback) {
+ /*
+ * modular subsystems can't use callbacks, so no need to lock
+ * the subsys array
+ */
+ for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+ struct cgroup_subsys *ss = subsys[i];
+ if (ss->exit) {
+ struct cgroup *old_cgrp =
+ rcu_dereference_raw(cg->subsys[i])->cgroup;
+ struct cgroup *cgrp = task_cgroup(tsk, i);
+ ss->exit(ss, cgrp, old_cgrp, tsk);
+ }
+ }
+ }
task_unlock(tsk);
+
if (cg)
put_css_set_taskexit(cg);
}
@@ -4813,6 +4818,29 @@ css_get_next(struct cgroup_subsys *ss, int id,
return ret;
}
+/*
+ * get corresponding css from file open on cgroupfs directory
+ */
+struct cgroup_subsys_state *cgroup_css_from_dir(struct file *f, int id)
+{
+ struct cgroup *cgrp;
+ struct inode *inode;
+ struct cgroup_subsys_state *css;
+
+ inode = f->f_dentry->d_inode;
+ /* check in cgroup filesystem dir */
+ if (inode->i_op != &cgroup_dir_inode_operations)
+ return ERR_PTR(-EBADF);
+
+ if (id < 0 || id >= CGROUP_SUBSYS_COUNT)
+ return ERR_PTR(-EINVAL);
+
+ /* get cgroup */
+ cgrp = __d_cgrp(f->f_dentry);
+ css = cgrp->subsys[id];
+ return css ? css : ERR_PTR(-ENOENT);
+}
+
#ifdef CONFIG_CGROUP_DEBUG
static struct cgroup_subsys_state *debug_create(struct cgroup_subsys *ss,
struct cgroup *cont)