diff options
| -rw-r--r-- | Documentation/cgroups.txt | 3 | ||||
| -rw-r--r-- | kernel/cgroup.c | 35 |
2 files changed, 10 insertions, 28 deletions
diff --git a/Documentation/cgroups.txt b/Documentation/cgroups.txt index 31d12e21ff8a..c298a6690e0d 100644 --- a/Documentation/cgroups.txt +++ b/Documentation/cgroups.txt @@ -500,8 +500,7 @@ post-attachment activity that requires memory allocations or blocking. void fork(struct cgroup_subsy *ss, struct task_struct *task) -Called when a task is forked into a cgroup. Also called during -registration for all existing tasks. +Called when a task is forked into a cgroup. void exit(struct cgroup_subsys *ss, struct task_struct *task) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index c447c29f8749..b893c8c94858 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2477,7 +2477,6 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry) static void __init cgroup_init_subsys(struct cgroup_subsys *ss) { struct cgroup_subsys_state *css; - struct list_head *l; printk(KERN_INFO "Initializing cgroup subsys %s\n", ss->name); @@ -2488,35 +2487,19 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss) BUG_ON(IS_ERR(css)); init_cgroup_css(css, ss, dummytop); - /* Update all cgroup groups to contain a subsys + /* Update the init_css_set to contain a subsys * pointer to this state - since the subsystem is - * newly registered, all tasks and hence all cgroup - * groups are in the subsystem's top cgroup. */ - write_lock(&css_set_lock); - l = &init_css_set.list; - do { - struct css_set *cg = - list_entry(l, struct css_set, list); - cg->subsys[ss->subsys_id] = dummytop->subsys[ss->subsys_id]; - l = l->next; - } while (l != &init_css_set.list); - write_unlock(&css_set_lock); - - /* If this subsystem requested that it be notified with fork - * events, we should send it one now for every process in the - * system */ - if (ss->fork) { - struct task_struct *g, *p; - - read_lock(&tasklist_lock); - do_each_thread(g, p) { - ss->fork(ss, p); - } while_each_thread(g, p); - read_unlock(&tasklist_lock); - } + * newly registered, all tasks and hence the + * init_css_set is in the subsystem's top cgroup. */ + init_css_set.subsys[ss->subsys_id] = dummytop->subsys[ss->subsys_id]; need_forkexit_callback |= ss->fork || ss->exit; + /* At system boot, before all subsystems have been + * registered, no tasks have been forked, so we don't + * need to invoke fork callbacks here. */ + BUG_ON(!list_empty(&init_task.tasks)); + ss->active = 1; } |