pid namespaces: miscellaneous preparations for pid namespaces

* remove pid.h from pid_namespaces.h;
* rework is_(cgroup|global)_init;
* optimize (get|put)_pid_ns for init_pid_ns;
* declare task_child_reaper to return actual reaper.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 7 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 511cc4549f5..b0bf326143a 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1329,19 +1329,17 @@ static inline int pid_alive(struct task_struct *p)
  * @tsk: Task structure to be checked.
  *
  * Check if a task structure is the first user space task the kernel created.
- *
- * TODO: We should inline this function after some cleanups in pid_namespace.h
  */
-extern int is_global_init(struct task_struct *tsk);
+static inline int is_global_init(struct task_struct *tsk)
+{
+	return tsk->pid == 1;
+}
 
 /*
  * is_container_init:
  * check whether in the task is init in its own pid namespace.
  */
-static inline int is_container_init(struct task_struct *tsk)
-{
-	return tsk->pid == 1;
-}
+extern int is_container_init(struct task_struct *tsk);
 
 extern struct pid *cad_pid;