rcu: Remove rsp parameter from rcu_do_batch()

There now is only one rcu_state structure in a given build of the
Linux kernel, so there is no need to pass it as a parameter to RCU's
functions.  This commit therefore removes the rsp parameter from
rcu_do_batch().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

kernel/rcu/tree.c

@@ -2490,12 +2490,13 @@ int rcutree_dead_cpu(unsigned int cpu)
  * Invoke any RCU callbacks that have made it to the end of their grace
  * period.  Thottle as specified by rdp->blimit.
  */
-static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
+static void rcu_do_batch(struct rcu_data *rdp)
 {
 	unsigned long flags;
 	struct rcu_head *rhp;
 	struct rcu_cblist rcl = RCU_CBLIST_INITIALIZER(rcl);
 	long bl, count;
+	struct rcu_state *rsp = &rcu_state;
 
 	/* If no callbacks are ready, just return. */
 	if (!rcu_segcblist_ready_cbs(&rdp->cblist)) {
@@ -2808,7 +2809,7 @@ static void invoke_rcu_callbacks(struct rcu_data *rdp)
 	if (unlikely(!READ_ONCE(rcu_scheduler_fully_active)))
 		return;
 	if (likely(!rsp->boost)) {
-		rcu_do_batch(rsp, rdp);
+		rcu_do_batch(rdp);
 		return;
 	}
 	invoke_rcu_callbacks_kthread();

kernel/rcu/tree_plugin.h

@@ -1324,7 +1324,7 @@ static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
 
 static void rcu_kthread_do_work(void)
 {
-	rcu_do_batch(&rcu_state, this_cpu_ptr(&rcu_data));
+	rcu_do_batch(this_cpu_ptr(&rcu_data));
 }
 
 static void rcu_cpu_kthread_setup(unsigned int cpu)