1 files changed, 8 insertions, 2 deletions

diff --git a/kernel/rcupreempt.c b/kernel/rcupreempt.c
index 7d777c9f394c..0053ce56e326 100644
--- a/kernel/rcupreempt.c
+++ b/kernel/rcupreempt.c
@@ -159,6 +159,8 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(struct rcu_dyntick_sched, rcu_dyntick_sched
         .dynticks = 1,
 };
 
+static int rcu_pending(int cpu);
+
 void rcu_sched_qs(int cpu)
 {
         struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
@@ -961,7 +963,10 @@ static void rcu_check_mb(int cpu)
 void rcu_check_callbacks(int cpu, int user)
 {
         unsigned long flags;
-        struct rcu_data *rdp = RCU_DATA_CPU(cpu);
+        struct rcu_data *rdp;
+
+        if (!rcu_pending(cpu))
+                return; /* if nothing for RCU to do. */
 
         /*
          * If this CPU took its interrupt from user mode or from the
@@ -976,6 +981,7 @@ void rcu_check_callbacks(int cpu, int user)
          * CPUs to happen after any such write.
          */
 
+        rdp = RCU_DATA_CPU(cpu);
         if (user ||
             (idle_cpu(cpu) && !in_softirq() &&
              hardirq_count() <= (1 << HARDIRQ_SHIFT))) {
@@ -1382,7 +1388,7 @@ int rcu_needs_cpu(int cpu)
                 rdp->waitschedlist != NULL);
 }
 
-int rcu_pending(int cpu)
+static int rcu_pending(int cpu)
 {
         struct rcu_data *rdp = RCU_DATA_CPU(cpu);