X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=kernel%2Fcgroup.c;h=0c753ddd223bf9d543dfbb2d89915a08ab537f46;hb=632b06aa2842b12c6d6a510ec080fb6ebdb38ea5;hp=52719ce55dd3dfefd24e8084e181de3d0ed95ea2;hpb=0ab02ca8f887908152d1a96db5130fc661d36a1e;p=~andy%2Flinux

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 52719ce55dd..0c753ddd223 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2905,9 +2905,14 @@ static void cgroup_enable_task_cg_lists(void)
 		 * We should check if the process is exiting, otherwise
 		 * it will race with cgroup_exit() in that the list
 		 * entry won't be deleted though the process has exited.
+		 * Do it while holding siglock so that we don't end up
+		 * racing against cgroup_exit().
 		 */
+		spin_lock_irq(&p->sighand->siglock);
 		if (!(p->flags & PF_EXITING) && list_empty(&p->cg_list))
 			list_add(&p->cg_list, &task_css_set(p)->tasks);
+		spin_unlock_irq(&p->sighand->siglock);
+
 		task_unlock(p);
 	} while_each_thread(g, p);
 	read_unlock(&tasklist_lock);
@@ -4107,17 +4112,17 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
 
 	err = percpu_ref_init(&css->refcnt, css_release);
 	if (err)
-		goto err_free;
+		goto err_free_css;
 
 	init_css(css, ss, cgrp);
 
 	err = cgroup_populate_dir(cgrp, 1 << ss->subsys_id);
 	if (err)
-		goto err_free;
+		goto err_free_percpu_ref;
 
 	err = online_css(css);
 	if (err)
-		goto err_free;
+		goto err_clear_dir;
 
 	dget(cgrp->dentry);
 	css_get(css->parent);
@@ -4133,8 +4138,11 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
 
 	return 0;
 
-err_free:
+err_clear_dir:
+	cgroup_clear_dir(css->cgroup, 1 << css->ss->subsys_id);
+err_free_percpu_ref:
 	percpu_ref_cancel_init(&css->refcnt);
+err_free_css:
 	ss->css_free(css);
 	return err;
 }
@@ -4844,16 +4852,12 @@ static int __init cgroup_wq_init(void)
 	/*
 	 * There isn't much point in executing destruction path in
 	 * parallel.  Good chunk is serialized with cgroup_mutex anyway.
-	 *
-	 * XXX: Must be ordered to make sure parent is offlined after
-	 * children.  The ordering requirement is for memcg where a
-	 * parent's offline may wait for a child's leading to deadlock.  In
-	 * the long term, this should be fixed from memcg side.
+	 * Use 1 for @max_active.
 	 *
 	 * We would prefer to do this in cgroup_init() above, but that
 	 * is called before init_workqueues(): so leave this until after.
 	 */
-	cgroup_destroy_wq = alloc_ordered_workqueue("cgroup_destroy", 0);
+	cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1);
 	BUG_ON(!cgroup_destroy_wq);
 
 	/*