1 files changed, 5 insertions, 1 deletions

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index a9f51031d3e8..d47e03e5792a 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -60,7 +60,8 @@ static struct lock_class_key rcu_node_class[NUM_RCU_LVLS];
                 NUM_RCU_LVL_0,  /* root of hierarchy. */ \
                 NUM_RCU_LVL_1, \
                 NUM_RCU_LVL_2, \
-                NUM_RCU_LVL_3, /* == MAX_RCU_LVLS */ \
+                NUM_RCU_LVL_3, \
+                NUM_RCU_LVL_4, /* == MAX_RCU_LVLS */ \
         }, \
         .signaled = RCU_GP_IDLE, \
         .gpnum = -300, \
@@ -1877,6 +1878,9 @@ void __init rcu_init(void)
 #ifdef CONFIG_RCU_CPU_STALL_DETECTOR
         printk(KERN_INFO "RCU-based detection of stalled CPUs is enabled.\n");
 #endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+#if NUM_RCU_LVL_4 != 0
+        printk(KERN_INFO "Experimental four-level hierarchy is enabled.\n");
+#endif /* #if NUM_RCU_LVL_4 != 0 */
         RCU_INIT_FLAVOR(&rcu_sched_state, rcu_sched_data);
         RCU_INIT_FLAVOR(&rcu_bh_state, rcu_bh_data);
         __rcu_init_preempt();