[PATCH] m68k: introduce task_thread_info

new helper - task_thread_info(task).  On platforms that have thread_info
allocated separately (i.e.  in default case) it simply returns
task->thread_info.  m68k wants (and for good reasons) to embed its thread_info
into task_struct.  So it will (in later patch) have task_thread_info() of its
own.  For now we just add a macro for generic case and convert existing
instances of its body in core kernel to uses of new macro.  Obviously safe -
all normal architectures get the same preprocessor output they used to get.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/fork.c b/kernel/fork.c
index 158710d..7ef352c 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -919,7 +919,7 @@
 	if (nr_threads >= max_threads)
 		goto bad_fork_cleanup_count;
 
-	if (!try_module_get(p->thread_info->exec_domain->module))
+	if (!try_module_get(task_thread_info(p)->exec_domain->module))
 		goto bad_fork_cleanup_count;
 
 	if (p->binfmt && !try_module_get(p->binfmt->module))
@@ -1180,7 +1180,7 @@
 	if (p->binfmt)
 		module_put(p->binfmt->module);
 bad_fork_cleanup_put_domain:
-	module_put(p->thread_info->exec_domain->module);
+	module_put(task_thread_info(p)->exec_domain->module);
 bad_fork_cleanup_count:
 	put_group_info(p->group_info);
 	atomic_dec(&p->user->processes);