Merge branch 'master'

1 files changed, 19 insertions, 0 deletions

diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index 6d32ff26f948..2058f88c7bbb 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -479,12 +479,31 @@ static int __rcu_pending(struct rcu_ctrlblk *rcp, struct rcu_data *rdp)
         return 0;
 }
 
+/*
+ * Check to see if there is any immediate RCU-related work to be done
+ * by the current CPU, returning 1 if so.  This function is part of the
+ * RCU implementation; it is -not- an exported member of the RCU API.
+ */
 int rcu_pending(int cpu)
 {
         return __rcu_pending(&rcu_ctrlblk, &per_cpu(rcu_data, cpu)) ||
                 __rcu_pending(&rcu_bh_ctrlblk, &per_cpu(rcu_bh_data, cpu));
 }
 
+/*
+ * Check to see if any future RCU-related work will need to be done
+ * by the current CPU, even if none need be done immediately, returning
+ * 1 if so.  This function is part of the RCU implementation; it is -not-
+ * an exported member of the RCU API.
+ */
+int rcu_needs_cpu(int cpu)
+{
+        struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
+        struct rcu_data *rdp_bh = &per_cpu(rcu_bh_data, cpu);
+
+        return (!!rdp->curlist || !!rdp_bh->curlist || rcu_pending(cpu));
+}
+
 void rcu_check_callbacks(int cpu, int user)
 {
         if (user ||