kmemtrace, rcu: fix rcu_tree_trace.c data structure dependencies

Impact: cleanup

We want to remove rcutree internals from the public rcutree.h file for
upcoming kmemtrace changes - but kernel/rcutree_trace.c depends on them.

Introduce kernel/rcutree.h for internal definitions. (Probably all
the other data types from include/linux/rcutree.h could be
moved here too - except rcu_data.)

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: paulmck@linux.vnet.ibm.com
LKML-Reference: <1237898630.25315.83.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/rcutree.c

@@ -72,11 +72,11 @@ EXPORT_SYMBOL_GPL(rcu_lock_map);
 	.n_force_qs_ngp = 0, \
 }
 
-static struct rcu_state rcu_state = RCU_STATE_INITIALIZER(rcu_state);
-static DEFINE_PER_CPU(struct rcu_data, rcu_data);
+struct rcu_state rcu_state = RCU_STATE_INITIALIZER(rcu_state);
+DEFINE_PER_CPU(struct rcu_data, rcu_data);
 
-static struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh_state);
-static DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
+struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh_state);
+DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
 
 /*
  * Increment the quiescent state counter.

kernel/rcutree.h

@@ -0,0 +1,10 @@
+
+/*
+ * RCU implementation internal declarations:
+ */
+extern struct rcu_state rcu_state;
+DECLARE_PER_CPU(struct rcu_data, rcu_data);
+
+extern struct rcu_state rcu_bh_state;
+DECLARE_PER_CPU(struct rcu_data, rcu_bh_data);
+

kernel/rcutree_trace.c

@@ -43,6 +43,8 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 
+#include "rcutree.h"
+
 static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
 {
 	if (!rdp->beenonline)