cgroup, cpuset: remove cgroup_subsys->post_clone()

Currently CGRP_CPUSET_CLONE_CHILDREN triggers ->post_clone().  Now
that clone_children is cpuset specific, there's no reason to have this
rather odd option activation mechanism in cgroup core.  cpuset can
check the flag from its ->css_allocate() and take the necessary
action.

Move cpuset_post_clone() logic to the end of cpuset_css_alloc() and
remove cgroup_subsys->post_clone().

Loosely based on Glauber's "generalize post_clone into post_create"
patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Original-patch-by: Glauber Costa <glommer@parallels.com>
Original-patch: <1351686554-22592-2-git-send-email-glommer@parallels.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Glauber Costa <glommer@parallels.com>

1 files changed, 0 insertions, 4 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2895880e6800..96719f73e95d 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4142,10 +4142,6 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
                         if (err)
                                 goto err_free_all;
                 }
-                /* At error, ->css_free() callback has to free assigned ID. */
-                if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &parent->flags) &&
-                    ss->post_clone)
-                        ss->post_clone(cgrp);
 
                 if (ss->broken_hierarchy && !ss->warned_broken_hierarchy &&
                     parent->parent) {