rcu: Fix rcu_lock_map build failure on CONFIG_PROVE_LOCKING=y

Move the rcu_lock_map definition from rcutree.c to rcupdate.c so that
TINY_RCU can use lockdep.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 7 insertions, 0 deletions

diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index 8e795133b33d..4a189ea18b48 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -46,6 +46,13 @@
 #include <linux/module.h>
 #include <linux/kernel_stat.h>
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static struct lock_class_key rcu_lock_key;
+struct lockdep_map rcu_lock_map =
+        STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key);
+EXPORT_SYMBOL_GPL(rcu_lock_map);
+#endif
+
 enum rcu_barrier {
         RCU_BARRIER_STD,
         RCU_BARRIER_BH,