cgroups: add previous cgroup in can_attach_task/attach_task callbacks

[karo-tx-linux.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index d9d5648f3cdcc4bcde3a7a67afe845aa89dc2a1f..ba8f3ebeb0469a087096401a9f9b1d06afd69da2 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1844,7 +1844,7 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
                        }
                }
                if (ss->can_attach_task) {
-                       retval = ss->can_attach_task(cgrp, tsk);
+                       retval = ss->can_attach_task(cgrp, oldcgrp, tsk);
                        if (retval) {
                                failed_ss = ss;
                                goto out;
@@ -1860,7 +1860,7 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
                if (ss->pre_attach)
                        ss->pre_attach(cgrp);
                if (ss->attach_task)
-                       ss->attach_task(cgrp, tsk);
+                       ss->attach_task(cgrp, oldcgrp, tsk);
                if (ss->attach)
                        ss->attach(ss, cgrp, oldcgrp, tsk);
        }
@@ -2075,7 +2075,10 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                        /* run on each task in the threadgroup. */
                        for (i = 0; i < group_size; i++) {
                                tsk = flex_array_get_ptr(group, i);
-                               retval = ss->can_attach_task(cgrp, tsk);
+                               oldcgrp = task_cgroup_from_root(tsk, root);
+
+                               retval = ss->can_attach_task(cgrp,
+                                                            oldcgrp, tsk);
                                if (retval) {
                                        failed_ss = ss;
                                        cancel_failed_ss = true;
@@ -2141,7 +2144,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                        /* attach each task to each subsystem */
                        for_each_subsys(root, ss) {
                                if (ss->attach_task)
-                                       ss->attach_task(cgrp, tsk);
+                                       ss->attach_task(cgrp, oldcgrp, tsk);
                        }
                } else {
                        BUG_ON(retval != -ESRCH);