[PATCH] fill_tgid: cleanup delays accounting

fill_tgid() should skip not only an already exited group leader.  If the
task has ->exit_state != 0 it already did exit_notify(), so it also did
fill_tgid_exit()->delayacct_add_tsk(->signal->stats) and we should skip it
to avoid a double accounting.

This patch doesn't close the race completely, but it cleanups the code.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/taskstats.c

@@ -235,7 +235,7 @@ static int fill_tgid(pid_t tgid, struct task_struct *first,
 
 	tsk = first;
 	do {
-		if (tsk->exit_state == EXIT_ZOMBIE && thread_group_leader(tsk))
+		if (tsk->exit_state)
 			continue;
 		/*
 		 * Accounting subsystem can call its functions here to