Merge branch 'topic/pcm-estrpipe-in-pm' into for-linus

[pandora-kernel.git] / include / linux / cgroup.h

diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 665fa70..90bba9e 100644 (file)
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -179,14 +179,11 @@ struct cgroup {
         */
        struct list_head release_list;
 
-       /* pids_mutex protects the fields below */
+       /* pids_mutex protects pids_list and cached pid arrays. */
        struct rw_semaphore pids_mutex;
-       /* Array of process ids in the cgroup */
-       pid_t *tasks_pids;
-       /* How many files are using the current tasks_pids array */
-       int pids_use_count;
-       /* Length of the current tasks_pids array */
-       int pids_length;
+
+       /* Linked list of struct cgroup_pids */
+       struct list_head pids_list;
 
        /* For RCU-protected deletion */
        struct rcu_head rcu_head;
@@ -365,6 +362,23 @@ int cgroup_task_count(const struct cgroup *cgrp);
 /* Return true if cgrp is a descendant of the task's cgroup */
 int cgroup_is_descendant(const struct cgroup *cgrp, struct task_struct *task);
 
+/*
+ * When the subsys has to access css and may add permanent refcnt to css,
+ * it should take care of racy conditions with rmdir(). Following set of
+ * functions, is for stop/restart rmdir if necessary.
+ * Because these will call css_get/put, "css" should be alive css.
+ *
+ *  cgroup_exclude_rmdir();
+ *  ...do some jobs which may access arbitrary empty cgroup
+ *  cgroup_release_and_wakeup_rmdir();
+ *
+ *  When someone removes a cgroup while cgroup_exclude_rmdir() holds it,
+ *  it sleeps and cgroup_release_and_wakeup_rmdir() will wake him up.
+ */
+
+void cgroup_exclude_rmdir(struct cgroup_subsys_state *css);
+void cgroup_release_and_wakeup_rmdir(struct cgroup_subsys_state *css);
+
 /*
  * Control Group subsystem type.
  * See Documentation/cgroups/cgroups.txt for details