[PATCH] kernel: make rcu/tree_trace.c explicitly non-modular

[Paul Gortmaker <paul.gortmaker@windriver.com>]

The Kconfig currently controlling compilation of this code is:

init/Kconfig:config TREE_RCU_TRACE
init/Kconfig:   def_bool RCU_TRACE && ( TREE_RCU || PREEMPT_RCU )

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the file there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.  We could
consider moving this to an earlier initcall if desired.

We don't replace module.h with init.h since the file already has that.
We also delete the moduleparam.h include that is left over from
commit 64db4cfff99c04cd5f550357edcc8780f96b54a2 (""Tree RCU": scalable
classic RCU implementation") since it is not needed here either.

We leave some tags like MODULE_AUTHOR for documentation purposes.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
index 6fc4c5ff3bb5..e8a0a11e8dd7 100644
--- a/kernel/rcu/tree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -33,9 +33,7 @@
 #include <linux/sched.h>
 #include <linux/atomic.h>
 #include <linux/bitops.h>
-#include <linux/module.h>
 #include <linux/completion.h>
-#include <linux/moduleparam.h>
 #include <linux/percpu.h>
 #include <linux/notifier.h>
 #include <linux/cpu.h>
@@ -487,16 +485,10 @@ free_out:
 	debugfs_remove_recursive(rcudir);
 	return 1;
 }
+device_initcall(rcutree_trace_init);
 
-static void __exit rcutree_trace_cleanup(void)
-{
-	debugfs_remove_recursive(rcudir);
-}
-
-
-module_init(rcutree_trace_init);
-module_exit(rcutree_trace_cleanup);
-
+/*
 MODULE_AUTHOR("Paul E. McKenney");
 MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
 MODULE_LICENSE("GPL");
+*/
-- 
2.5.0