cgroup: add cgroup->id
With the introduction of generic cgroup hierarchy iterators, css_id is
being phased out. It was unnecessarily complex, id'ing the wrong
thing (cgroups need IDs, not CSSes) and has other oddities like not
being available at ->css_alloc().
This patch adds cgroup->id, which is a simple per-hierarchy
ida-allocated ID which is assigned before ->css_alloc() and released
after ->css_free().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index c798997..82cf9e6 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -159,6 +159,8 @@
*/
atomic_t count;
+ int id; /* ida allocated in-hierarchy ID */
+
/*
* We link our 'sibling' struct into our parent's 'children'.
* Our children link their 'sibling' into our 'children'.