rcu: Re-arrange code to reduce #ifdef pain

Remove #ifdefs from kernel/rcupdate.c and
include/linux/rcupdate.h by moving code to
include/linux/rcutiny.h, include/linux/rcutree.h, and
kernel/rcutree.c.

Also remove some definitions that are no longer used.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1258908830885-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 14 insertions, 13 deletions

diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 2f1bc42..24440f4 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -52,11 +52,6 @@ struct rcu_head {
 };
 
 /* Exported common interfaces */
-#ifdef CONFIG_TREE_PREEMPT_RCU
-extern void synchronize_rcu(void);
-#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
-#define synchronize_rcu synchronize_sched
-#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */
 extern void synchronize_rcu_bh(void);
 extern void synchronize_sched(void);
 extern void rcu_barrier(void);
@@ -67,13 +62,6 @@ extern int sched_expedited_torture_stats(char *page);
 
 /* Internal to kernel */
 extern void rcu_init(void);
-extern void rcu_scheduler_starting(void);
-#ifndef CONFIG_TINY_RCU
-extern int rcu_needs_cpu(int cpu);
-#else
-static inline int rcu_needs_cpu(int cpu) { return 0; }
-#endif
-extern int rcu_scheduler_active;
 
 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU)
 #include <linux/rcutree.h>
diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h
index a3b6272..c4ba9a7 100644
--- a/include/linux/rcutiny.h
+++ b/include/linux/rcutiny.h
@@ -39,6 +39,11 @@ void rcu_bh_qs(int cpu);
 #define rcu_init_sched()	do { } while (0)
 extern void rcu_check_callbacks(int cpu, int user);
 
+static inline int rcu_needs_cpu(int cpu)
+{
+	return 0;
+}
+
 /*
  * Return the number of grace periods.
  */
@@ -57,6 +62,8 @@ static inline long rcu_batches_completed_bh(void)
 
 extern int rcu_expedited_torture_stats(char *page);
 
+#define synchronize_rcu synchronize_sched
+
 static inline void synchronize_rcu_expedited(void)
 {
 	synchronize_sched();
@@ -86,6 +93,10 @@ static inline void rcu_exit_nohz(void)
 
 #endif /* #else #ifdef CONFIG_NO_HZ */
 
+static inline void rcu_scheduler_starting(void)
+{
+}
+
 static inline void exit_rcu(void)
 {
 }
diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index 111a652..c93eee5 100644
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -35,12 +35,14 @@ struct notifier_block;
 extern void rcu_sched_qs(int cpu);
 extern void rcu_bh_qs(int cpu);
 extern int rcu_needs_cpu(int cpu);
+extern void rcu_scheduler_starting(void);
 extern int rcu_expedited_torture_stats(char *page);
 
 #ifdef CONFIG_TREE_PREEMPT_RCU
 
 extern void __rcu_read_lock(void);
 extern void __rcu_read_unlock(void);
+extern void synchronize_rcu(void);
 extern void exit_rcu(void);
 
 #else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
@@ -55,7 +57,7 @@ static inline void __rcu_read_unlock(void)
 	preempt_enable();
 }
 
-#define __synchronize_sched() synchronize_rcu()
+#define synchronize_rcu synchronize_sched
 
 static inline void exit_rcu(void)
 {