Merge branch 'for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:
 "All trivial changes - simplification, typo fix and adding
  cond_resched() in a netclassid update loop"

* 'for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup, netclassid: add a preemption point to write_classid
  rdmacg: fix a typo in rdmacg documentation
  cgroup: Simplify cgroup_ancestor

diff --combined include/linux/cgroup.h
index b8bcbdeb2eac428609da123c3f410806537ddae3,e03a92430383d7df4de0cc894574a214f3b881c6..b622d660860509d266008ebcf75175af7839c496
--- 1/include/linux/cgroup.h
--- 2/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@@ -93,8 -93,6 +93,8 @@@ extern struct css_set init_css_set
  
  bool css_has_online_children(struct cgroup_subsys_state *css);
  struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss);
 +struct cgroup_subsys_state *cgroup_e_css(struct cgroup *cgroup,
 +                                       struct cgroup_subsys *ss);
  struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgroup,
                                             struct cgroup_subsys *ss);
  struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
@@@ -569,20 -567,11 +569,11 @@@ static inline bool cgroup_is_descendant
  static inline struct cgroup *cgroup_ancestor(struct cgroup *cgrp,
                                             int ancestor_level)
  {
-       struct cgroup *ptr;
- 
        if (cgrp->level < ancestor_level)
                return NULL;
- 
-       for (ptr = cgrp;
-            ptr && ptr->level > ancestor_level;
-            ptr = cgroup_parent(ptr))
-               ;
- 
-       if (ptr && ptr->level == ancestor_level)
-               return ptr;
- 
-       return NULL;
+       while (cgrp && cgrp->level > ancestor_level)
+               cgrp = cgroup_parent(cgrp);
+       return cgrp;
  }
  
  /**