rcu: Remove rsp parameter from check_cpu_stall()

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

kernel/rcu/tree.c

@@ -1442,7 +1442,7 @@ static void print_cpu_stall(void)
 	resched_cpu(smp_processor_id());
 }
 
-static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
+static void check_cpu_stall(struct rcu_data *rdp)
 {
 	unsigned long gs1;
 	unsigned long gs2;
@@ -1451,6 +1451,7 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
 	unsigned long jn;
 	unsigned long js;
 	struct rcu_node *rnp;
+	struct rcu_state *rsp = &rcu_state;
 
 	if ((rcu_cpu_stall_suppress && !rcu_kick_kthreads) ||
 	    !rcu_gp_in_progress())
@@ -3094,7 +3095,7 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
 	struct rcu_node *rnp = rdp->mynode;
 
 	/* Check for CPU stalls, if enabled. */
-	check_cpu_stall(rsp, rdp);
+	check_cpu_stall(rdp);
 
 	/* Is this CPU a NO_HZ_FULL CPU that should ignore RCU? */
 	if (rcu_nohz_full_cpu(rsp))