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>
diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
index 416d4e4..0135c76 100644
--- a/include/linux/pid_namespace.h
+++ b/include/linux/pid_namespace.h
@@ -4,7 +4,6 @@
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/threads.h>
-#include <linux/pid.h>
#include <linux/nsproxy.h>
#include <linux/kref.h>
@@ -32,7 +31,8 @@
static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
{
- kref_get(&ns->kref);
+ if (ns != &init_pid_ns)
+ kref_get(&ns->kref);
return ns;
}
@@ -41,7 +41,8 @@
static inline void put_pid_ns(struct pid_namespace *ns)
{
- kref_put(&ns->kref, free_pid_ns);
+ if (ns != &init_pid_ns)
+ kref_put(&ns->kref, free_pid_ns);
}
static inline struct pid_namespace *task_active_pid_ns(struct task_struct *tsk)
@@ -51,7 +52,8 @@
static inline struct task_struct *task_child_reaper(struct task_struct *tsk)
{
- return init_pid_ns.child_reaper;
+ BUG_ON(tsk != current);
+ return tsk->nsproxy->pid_ns->child_reaper;
}
#endif /* _LINUX_PID_NS_H */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 511cc45..b0bf326 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1329,19 +1329,17 @@
* @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;