diff options
| -rw-r--r-- | include/linux/cgroup.h | 10 | ||||
| -rw-r--r-- | kernel/cgroup.c | 108 |
2 files changed, 36 insertions, 82 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index f7898e0bce1e..51958d0fb88f 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -234,13 +234,6 @@ struct cgroup { struct list_head e_csets[CGROUP_SUBSYS_COUNT]; /* - * Linked list running through all cgroups that can - * potentially be reaped by the release agent. Protected by - * release_list_lock - */ - struct list_head release_list; - - /* * list of pidlists, up to two for each namespace (one for procs, one * for tasks); created on demand. */ @@ -249,6 +242,9 @@ struct cgroup { /* used to wait for offlining of csses */ wait_queue_head_t offline_waitq; + + /* used to schedule release agent */ + struct work_struct release_agent_work; }; #define MAX_CGROUP_ROOT_NAMELEN 64 diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 4ddc75588983..db19a4884a7f 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -392,12 +392,7 @@ static int notify_on_release(const struct cgroup *cgrp) ; \ else -/* the list of cgroups eligible for automatic release. Protected by - * release_list_lock */ -static LIST_HEAD(release_list); -static DEFINE_RAW_SPINLOCK(release_list_lock); static void cgroup_release_agent(struct work_struct *work); -static DECLARE_WORK(release_agent_work, cgroup_release_agent); static void check_for_release(struct cgroup *cgrp); /* @@ -1577,7 +1572,6 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) INIT_LIST_HEAD(&cgrp->self.sibling); INIT_LIST_HEAD(&cgrp->self.children); INIT_LIST_HEAD(&cgrp->cset_links); - INIT_LIST_HEAD(&cgrp->release_list); INIT_LIST_HEAD(&cgrp->pidlists); mutex_init(&cgrp->pidlist_mutex); cgrp->self.cgroup = cgrp; @@ -1587,6 +1581,7 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) INIT_LIST_HEAD(&cgrp->e_csets[ssid]); init_waitqueue_head(&cgrp->offline_waitq); + INIT_WORK(&cgrp->release_agent_work, cgroup_release_agent); } static void init_cgroup_root(struct cgroup_root *root, @@ -4342,6 +4337,7 @@ static void css_free_work_fn(struct work_struct *work) /* cgroup free path */ atomic_dec(&cgrp->root->nr_cgrps); cgroup_pidlist_destroy_all(cgrp); + cancel_work_sync(&cgrp->release_agent_work); if (cgroup_parent(cgrp)) { /* @@ -4804,12 +4800,6 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) for_each_css(css, ssid, cgrp) kill_css(css); - /* CSS_ONLINE is clear, remove from ->release_list for the last time */ - raw_spin_lock(&release_list_lock); - if (!list_empty(&cgrp->release_list)) - list_del_init(&cgrp->release_list); - raw_spin_unlock(&release_list_lock); - /* * Remove @cgrp directory along with the base files. @cgrp has an * extra ref on its kn. @@ -5271,25 +5261,9 @@ void cgroup_exit(struct task_struct *tsk) static void check_for_release(struct cgroup *cgrp) { - if (cgroup_is_releasable(cgrp) && list_empty(&cgrp->cset_links) && - !css_has_online_children(&cgrp->self)) { - /* - * Control Group is currently removeable. If it's not - * already queued for a userspace notification, queue - * it now - */ - int need_schedule_work = 0; - - raw_spin_lock(&release_list_lock); - if (!cgroup_is_dead(cgrp) && - list_empty(&cgrp->release_list)) { - list_add(&cgrp->release_list, &release_list); - need_schedule_work = 1; - } - raw_spin_unlock(&release_list_lock); - if (need_schedule_work) - schedule_work(&release_agent_work); - } + if (cgroup_is_releasable(cgrp) && !cgroup_has_tasks(cgrp) && + !css_has_online_children(&cgrp->self) && !cgroup_is_dead(cgrp)) + schedule_work(&cgrp->release_agent_work); } /* @@ -5317,52 +5291,36 @@ static void check_for_release(struct cgroup *cgrp) */ static void cgroup_release_agent(struct work_struct *work) { - BUG_ON(work != &release_agent_work); + struct cgroup *cgrp = + container_of(work, struct cgroup, release_agent_work); + char *pathbuf = NULL, *agentbuf = NULL, *path; + char *argv[3], *envp[3]; + mutex_lock(&cgroup_mutex); - raw_spin_lock(&release_list_lock); - while (!list_empty(&release_list)) { - char *argv[3], *envp[3]; - int i; - char *pathbuf = NULL, *agentbuf = NULL, *path; - struct cgroup *cgrp = list_entry(release_list.next, - struct cgroup, - release_list); - list_del_init(&cgrp->release_list); - raw_spin_unlock(&release_list_lock); - pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); - if (!pathbuf) - goto continue_free; - path = cgroup_path(cgrp, pathbuf, PATH_MAX); - if (!path) - goto continue_free; - agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL); - if (!agentbuf) - goto continue_free; - - i = 0; - argv[i++] = agentbuf; - argv[i++] = path; - argv[i] = NULL; - - i = 0; - /* minimal command environment */ - envp[i++] = "HOME=/"; - envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin"; - envp[i] = NULL; - - /* Drop the lock while we invoke the usermode helper, - * since the exec could involve hitting disk and hence - * be a slow process */ - mutex_unlock(&cgroup_mutex); - call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC); - mutex_lock(&cgroup_mutex); - continue_free: - kfree(pathbuf); - kfree(agentbuf); - raw_spin_lock(&release_list_lock); - } - raw_spin_unlock(&release_list_lock); + + pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); + agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL); + if (!pathbuf || !agentbuf) + goto out; + + path = cgroup_path(cgrp, pathbuf, PATH_MAX); + if (!path) + goto out; + + argv[0] = agentbuf; + argv[1] = path; + argv[2] = NULL; + + /* minimal command environment */ + envp[0] = "HOME=/"; + envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin"; + envp[2] = NULL; + mutex_unlock(&cgroup_mutex); + call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC); +out: + kfree(agentbuf); + kfree(pathbuf); } static int __init cgroup_disable(char *str) |