pids: kill signal_struct-> __pgrp/__session and friends

We are wasting 2 words in signal_struct without any reason to implement
task_pgrp_nr() and task_session_nr().

task_session_nr() has no callers since
2e2ba22ea4fd4bb85f0fa37c521066db6775cbef, we can remove it.

task_pgrp_nr() is still (I believe wrongly) used in fs/autofsX and
fs/coda.

This patch reimplements task_pgrp_nr() via task_pgrp_nr_ns(), and kills
__pgrp/__session and the related helpers.

The change in drivers/char/tty_io.c is cosmetic, but hopefully makes sense
anyway.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Alan Cox <number6@the-village.bc.nu>		[tty parts]
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 37 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 49df878a0cad..206ac003e8c0 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -547,25 +547,8 @@ struct signal_struct {
 
         struct list_head cpu_timers[3];
 
-        /* job control IDs */
-
-        /*
-         * pgrp and session fields are deprecated.
-         * use the task_session_Xnr and task_pgrp_Xnr routines below
-         */
-
-        union {
-                pid_t pgrp __deprecated;
-                pid_t __pgrp;
-        };
-
         struct pid *tty_old_pgrp;
 
-        union {
-                pid_t session __deprecated;
-                pid_t __session;
-        };
-
         /* boolean value for session group leader */
         int leader;
 
@@ -1469,16 +1452,6 @@ static inline int rt_task(struct task_struct *p)
         return rt_prio(p->prio);
 }
 
-static inline void set_task_session(struct task_struct *tsk, pid_t session)
-{
-        tsk->signal->__session = session;
-}
-
-static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp)
-{
-        tsk->signal->__pgrp = pgrp;
-}
-
 static inline struct pid *task_pid(struct task_struct *task)
 {
         return task->pids[PIDTYPE_PID].pid;
@@ -1552,11 +1525,6 @@ static inline pid_t task_tgid_vnr(struct task_struct *tsk)
 }
 
 
-static inline pid_t task_pgrp_nr(struct task_struct *tsk)
-{
-        return tsk->signal->__pgrp;
-}
-
 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
                                         struct pid_namespace *ns)
 {
@@ -1569,11 +1537,6 @@ static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
 }
 
 
-static inline pid_t task_session_nr(struct task_struct *tsk)
-{
-        return tsk->signal->__session;
-}
-
 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
                                         struct pid_namespace *ns)
 {
@@ -1585,6 +1548,12 @@ static inline pid_t task_session_vnr(struct task_struct *tsk)
         return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
 }
 
+/* obsolete, do not use */
+static inline pid_t task_pgrp_nr(struct task_struct *tsk)
+{
+        return task_pgrp_nr_ns(tsk, &init_pid_ns);
+}
+
 /**
  * pid_alive - check that a task structure is not stale
  * @p: Task structure to be checked.