cgroups: new cancel_attach_task() subsystem callback

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

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 90b508d366741802cf28f5483dacaeff510d3271..b0686b49dd4b58093ff94ad687c7ae140cb3da8d 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1883,6 +1883,9 @@ out:
                                 * remaining subsystems.
                                 */
                                break;
+
+                       if (ss->cancel_attach_task)
+                               ss->cancel_attach_task(cgrp, tsk);
                        if (ss->cancel_attach)
                                ss->cancel_attach(ss, cgrp, tsk);
                }
@@ -1992,7 +1995,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
 {
        int retval, i, group_size;
        struct cgroup_subsys *ss, *failed_ss = NULL;
-       bool cancel_failed_ss = false;
+       struct task_struct *failed_task = NULL;
        /* guaranteed to be initialized later, but the compiler needs this */
        struct cgroup *oldcgrp = NULL;
        struct css_set *oldcg;
@@ -2081,7 +2084,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                                                             oldcgrp, tsk);
                                if (retval) {
                                        failed_ss = ss;
-                                       cancel_failed_ss = true;
+                                       failed_task = tsk;
                                        goto out_cancel_attach;
                                }
                        }
@@ -2146,8 +2149,11 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                                if (ss->attach_task)
                                        ss->attach_task(cgrp, oldcgrp, tsk);
                        }
+               } else if (retval == -ESRCH) {
+                       if (ss->cancel_attach_task)
+                               ss->cancel_attach_task(cgrp, tsk);
                } else {
-                       BUG_ON(retval != -ESRCH);
+                       BUG_ON(1);
                }
        }
        /* nothing is sensitive to fork() after this point. */
@@ -2179,8 +2185,18 @@ out_cancel_attach:
        /* same deal as in cgroup_attach_task */
        if (retval) {
                for_each_subsys(root, ss) {
+                       if (ss->cancel_attach_task && (ss != failed_ss ||
+                                                      failed_task)) {
+                               for (i = 0; i < group_size; i++) {
+                                       tsk = flex_array_get_ptr(group, i);
+                                       if (tsk == failed_task)
+                                               break;
+                                       ss->cancel_attach_task(cgrp, tsk);
+                               }
+                       }
+
                        if (ss == failed_ss) {
-                               if (cancel_failed_ss && ss->cancel_attach)
+                               if (failed_task && ss->cancel_attach)
                                        ss->cancel_attach(ss, cgrp, leader);
                                break;
                        }