cgroups: if you list_empty() a head then don't list_del() it

[pandora-kernel.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 66a416b..a328a75 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1791,10 +1791,8 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
 
        /* Update the css_set linked lists if we're using them */
        write_lock(&css_set_lock);
-       if (!list_empty(&tsk->cg_list)) {
-               list_del(&tsk->cg_list);
-               list_add(&tsk->cg_list, &newcg->tasks);
-       }
+       if (!list_empty(&tsk->cg_list))
+               list_move(&tsk->cg_list, &newcg->tasks);
        write_unlock(&css_set_lock);
 
        for_each_subsys(root, ss) {
@@ -3630,12 +3628,12 @@ again:
        spin_lock(&release_list_lock);
        set_bit(CGRP_REMOVED, &cgrp->flags);
        if (!list_empty(&cgrp->release_list))
-               list_del(&cgrp->release_list);
+               list_del_init(&cgrp->release_list);
        spin_unlock(&release_list_lock);
 
        cgroup_lock_hierarchy(cgrp->root);
        /* delete this cgroup from parent->children */
-       list_del(&cgrp->sibling);
+       list_del_init(&cgrp->sibling);
        cgroup_unlock_hierarchy(cgrp->root);
 
        spin_lock(&cgrp->dentry->d_lock);
@@ -3856,7 +3854,7 @@ void cgroup_unload_subsys(struct cgroup_subsys *ss)
        subsys[ss->subsys_id] = NULL;
 
        /* remove subsystem from rootnode's list of subsystems */
-       list_del(&ss->sibling);
+       list_del_init(&ss->sibling);
 
        /*
         * disentangle the css from all css_sets attached to the dummytop. as
@@ -4230,7 +4228,7 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
        if (!list_empty(&tsk->cg_list)) {
                write_lock(&css_set_lock);
                if (!list_empty(&tsk->cg_list))
-                       list_del(&tsk->cg_list);
+                       list_del_init(&tsk->cg_list);
                write_unlock(&css_set_lock);
        }