[Devel] [PATCH] Brush up task session manipulation routines

[Pavel Emelianov]

The function names process_session() and task_session() are
somewhat discouraging. Functions set_signal_session() and 
signal_session() are never used for "orphaned" signals - 
there's always a task to take it from.

So I propose to:
* rename process_session() to task_session_nr() to make it
  symmetrical to task_session(),
* replace signal_session() with task_session_nr() and
  set_signal_session() with set_task_session() not to make
  redundant essences.

If this looks reasonable, further proposal would be to make
process_group() be symmetrical to task_pgrp() the same way.

Fits 2.6.21-mm2

Signed-off-by: Pavel Emelianov <xemul at openvz.org>

---

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 74f30e0..1eee446 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -381,7 +381,7 @@ static int do_task_stat(struct task_stru
 			stime = cputime_add(stime, sig->stime);
 		}
 
-		sid = signal_session(sig);
+		sid = task_session_nr(task);
 		pgid = process_group(task);
 		ppid = rcu_dereference(task->real_parent)->tgid;
 
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 40645b4..66b59db 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1099,19 +1099,14 @@ static inline pid_t process_group(struct
 	return tsk->signal->pgrp;
 }
 
-static inline pid_t signal_session(struct signal_struct *sig)
+static inline pid_t task_session_nr(struct task_struct *tsk)
 {
-	return sig->__session;
+	return tsk->signal->__session;
 }
 
-static inline pid_t process_session(struct task_struct *tsk)
+static inline void set_task_session(struct task_struct *tsk, pid_t session)
 {
-	return signal_session(tsk->signal);
-}
-
-static inline void set_signal_session(struct signal_struct *sig, pid_t session)
-{
-	sig->__session = session;
+	tsk->sig->__session = session;
 }
 
 static inline struct pid *task_pid(struct task_struct *task)
diff --git a/kernel/exit.c b/kernel/exit.c
index c6d14b8..e9ad2c3 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -310,7 +310,7 @@ void __set_special_pids(pid_t session, p
 
 	if (process_session(curr) != session) {
 		detach_pid(curr, PIDTYPE_SID);
-		set_signal_session(curr->signal, session);
+		set_task_session(curr, session);
 		attach_pid(curr, PIDTYPE_SID, find_pid(session));
 	}
 	if (process_group(curr) != pgrp) {
diff --git a/kernel/fork.c b/kernel/fork.c
index 4239de2..090e3a1 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1252,7 +1252,7 @@ static struct task_struct *copy_process(
 		if (thread_group_leader(p)) {
 			p->signal->tty = current->signal->tty;
 			p->signal->pgrp = process_group(current);
-			set_signal_session(p->signal, process_session(current));
+			set_task_session(p, task_session_nr(current));
 			attach_pid(p, PIDTYPE_PGID, task_pgrp(current));
 			attach_pid(p, PIDTYPE_SID, task_session(current));