diff options
| author | Li Zefan <lizefan@huawei.com> | 2012-06-06 19:12:30 -0700 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2012-06-06 19:12:30 -0700 |
| commit | 6be96a5c905178637ec06a5d456a76b2b304fca3 (patch) | |
| tree | 06cc22397df498c7e4dbb7195f77d1bc587295e3 /include | |
| parent | 967db0ea65b0bf8507a7643ac8f296c4f2c0a834 (diff) | |
cgroup: remove hierarchy_mutex
It was introduced for memcg to iterate cgroup hierarchy without
holding cgroup_mutex, but soon after that it was replaced with
a lockless way in memcg.
No one used hierarchy_mutex since that, so remove it.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/cgroup.h | 17 |
1 files changed, 2 insertions, 15 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index d3f5fba2c15..c90eaa80344 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -500,21 +500,8 @@ struct cgroup_subsys { const char *name; /* - * Protects sibling/children links of cgroups in this - * hierarchy, plus protects which hierarchy (or none) the - * subsystem is a part of (i.e. root/sibling). To avoid - * potential deadlocks, the following operations should not be - * undertaken while holding any hierarchy_mutex: - * - * - allocating memory - * - initiating hotplug events - */ - struct mutex hierarchy_mutex; - struct lock_class_key subsys_key; - - /* * Link to parent, and list entry in parent's children. - * Protected by this->hierarchy_mutex and cgroup_lock() + * Protected by cgroup_lock() */ struct cgroupfs_root *root; struct list_head sibling; @@ -602,7 +589,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *); * the lifetime of cgroup_subsys_state is subsys's matter. * * Looking up and scanning function should be called under rcu_read_lock(). - * Taking cgroup_mutex()/hierarchy_mutex() is not necessary for following calls. + * Taking cgroup_mutex is not necessary for following calls. * But the css returned by this routine can be "not populated yet" or "being * destroyed". The caller should check css and cgroup's status. */ |