CGroup API files: move "releasable" to cgroup_debug subsystem

The "releasable" control file provided by the cgroup framework exports the
state of a per-cgroup flag that's related to the notify-on-release feature.
This isn't really generally useful, unless you're trying to debug this
particular feature of cgroups.

This patch moves the "releasable" file to the cgroup_debug subsystem.

Signed-off-by: Paul Menage <menage@google.com>
Cc: "Li Zefan" <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "YAMAMOTO Takashi" <yamamoto@valinux.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 11 insertions, 1 deletions

diff --git a/kernel/cgroup_debug.c b/kernel/cgroup_debug.c
index cbb7a26f4ea3..c3dc3aba4c02 100644
--- a/kernel/cgroup_debug.c
+++ b/kernel/cgroup_debug.c
@@ -1,5 +1,5 @@
 /*
- * kernel/ccontainer_debug.c - Example cgroup subsystem that
+ * kernel/cgroup_debug.c - Example cgroup subsystem that
  * exposes debug info
  *
  * Copyright (C) Google Inc, 2007
@@ -62,6 +62,11 @@ static u64 current_css_set_refcount_read(struct cgroup *cont,
         return count;
 }
 
+static u64 releasable_read(struct cgroup *cgrp, struct cftype *cft)
+{
+        return test_bit(CGRP_RELEASABLE, &cgrp->flags);
+}
+
 static struct cftype files[] =  {
         {
                 .name = "cgroup_refcount",
@@ -81,6 +86,11 @@ static struct cftype files[] =  {
                 .name = "current_css_set_refcount",
                 .read_u64 = current_css_set_refcount_read,
         },
+
+        {
+                .name = "releasable",
+                .read_u64 = releasable_read,
+        }
 };
 
 static int debug_populate(struct cgroup_subsys *ss, struct cgroup *cont)