cgroup: notify ns_cgroup deprecated

The ns_cgroup will be removed very soon.  Let's warn, for this version,
ns_cgroup is deprecated.

Make ns_cgroup and clone_children exclusive.  If the clone_children is set
and the ns_cgroup is mounted, let's fail with EINVAL when the ns_cgroup
subsys is created (a printk will help the user to understand why the
creation fails).

Update the feature remove schedule file with the deprecated ns_cgroup.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Daniel Lezcano 2010-10-27 15:33:38 -07:00 committed by Linus Torvalds
parent f4a2589fea
commit 45531757b4
2 changed files with 25 additions and 0 deletions

View file

@ -526,6 +526,23 @@ Who: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
----------------------------
What: namespace cgroup (ns_cgroup)
When: 2.6.38
Why: The ns_cgroup leads to some problems:
* cgroup creation is out-of-control
* cgroup name can conflict when pids are looping
* it is not possible to have a single process handling
a lot of namespaces without falling in a exponential creation time
* we may want to create a namespace without creating a cgroup
The ns_cgroup is replaced by a compatibility flag 'clone_children',
where a newly created cgroup will copy the parent cgroup values.
The userspace has to manually create a cgroup and add a task to
the 'tasks' file.
Who: Daniel Lezcano <daniel.lezcano@free.fr>
----------------------------
What: iwlwifi disable_hw_scan module parameters
When: 2.6.40
Why: Hareware scan is the prefer method for iwlwifi devices for

View file

@ -85,6 +85,14 @@ static struct cgroup_subsys_state *ns_create(struct cgroup_subsys *ss,
return ERR_PTR(-EPERM);
if (!cgroup_is_descendant(cgroup, current))
return ERR_PTR(-EPERM);
if (test_bit(CGRP_CLONE_CHILDREN, &cgroup->flags)) {
printk("ns_cgroup can't be created with parent "
"'clone_children' set.\n");
return ERR_PTR(-EINVAL);
}
printk_once("ns_cgroup deprecated: consider using the "
"'clone_children' flag without the ns_cgroup.\n");
ns_cgroup = kzalloc(sizeof(*ns_cgroup), GFP_KERNEL);
if (!ns_cgroup)