Merge branch 'for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

[linux-2.6-microblaze.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 75c0ff0..33a2f63 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -61,7 +61,6 @@
 #include <linux/cpuset.h>
 #include <linux/proc_ns.h>
 #include <linux/nsproxy.h>
-#include <linux/proc_ns.h>
 #include <net/sock.h>
 
 /*
@@ -1160,18 +1159,12 @@ static void cgroup_exit_root_id(struct cgroup_root *root)
 {
        lockdep_assert_held(&cgroup_mutex);
 
-       if (root->hierarchy_id) {
-               idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id);
-               root->hierarchy_id = 0;
-       }
+       idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id);
 }
 
 static void cgroup_free_root(struct cgroup_root *root)
 {
        if (root) {
-               /* hierarchy ID should already have been released */
-               WARN_ON_ONCE(root->hierarchy_id);
-
                idr_destroy(&root->cgroup_idr);
                kfree(root);
        }
@@ -5146,6 +5139,8 @@ static struct cgroup_subsys_state *css_create(struct cgroup *cgrp,
        lockdep_assert_held(&cgroup_mutex);
 
        css = ss->css_alloc(parent_css);
+       if (!css)
+               css = ERR_PTR(-ENOMEM);
        if (IS_ERR(css))
                return css;
 
@@ -6172,7 +6167,7 @@ struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
 struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss)
 {
        WARN_ON_ONCE(!rcu_read_lock_held());
-       return id > 0 ? idr_find(&ss->css_idr, id) : NULL;
+       return idr_find(&ss->css_idr, id);
 }
 
 /**