diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt
index f935fac..c6256ae 100644
--- a/Documentation/cgroups/cgroups.txt
+++ b/Documentation/cgroups/cgroups.txt
@@ -637,6 +637,10 @@
 
 Called during task exit.
 
+void free(struct task_struct *task)
+
+Called when the task_struct is freed.
+
 void bind(struct cgroup *root)
 (cgroup_mutex held by caller)
 
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 6a1ab64..60d44b2 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -436,6 +436,7 @@
 	void (*cancel_fork)(struct task_struct *task, void *priv);
 	void (*fork)(struct task_struct *task, void *priv);
 	void (*exit)(struct task_struct *task);
+	void (*free)(struct task_struct *task);
 	void (*bind)(struct cgroup_subsys_state *root_css);
 
 	int early_init;
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 9186584..8673843 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -206,6 +206,7 @@
  */
 static unsigned long have_fork_callback __read_mostly;
 static unsigned long have_exit_callback __read_mostly;
+static unsigned long have_free_callback __read_mostly;
 
 /* Ditto for the can_fork callback. */
 static unsigned long have_canfork_callback __read_mostly;
@@ -5180,6 +5181,7 @@
 
 	have_fork_callback |= (bool)ss->fork << ss->id;
 	have_exit_callback |= (bool)ss->exit << ss->id;
+	have_free_callback |= (bool)ss->free << ss->id;
 	have_canfork_callback |= (bool)ss->can_fork << ss->id;
 
 	/* At system boot, before all subsystems have been
@@ -5637,6 +5639,11 @@
 void cgroup_free(struct task_struct *task)
 {
 	struct css_set *cset = task_css_set(task);
+	struct cgroup_subsys *ss;
+	int ssid;
+
+	for_each_subsys_which(ss, ssid, &have_free_callback)
+		ss->free(task);
 
 	put_css_set(cset);
 }
diff --git a/kernel/cgroup_pids.c b/kernel/cgroup_pids.c
index 45f0856..cdd8df4 100644
--- a/kernel/cgroup_pids.c
+++ b/kernel/cgroup_pids.c
@@ -266,7 +266,7 @@
 	css_put(old_css);
 }
 
-static void pids_exit(struct task_struct *task)
+static void pids_free(struct task_struct *task)
 {
 	struct pids_cgroup *pids = css_pids(task_css(task, pids_cgrp_id));
 
@@ -347,7 +347,7 @@
 	.can_fork	= pids_can_fork,
 	.cancel_fork	= pids_cancel_fork,
 	.fork		= pids_fork,
-	.exit		= pids_exit,
+	.free		= pids_free,
 	.legacy_cftypes	= pids_files,
 	.dfl_cftypes	= pids_files,
 };