rcu: Invert sync_rcu_exp_select_cpus() "if" statement

This commit saves a couple lines of code and reduces indentation
by inverting the sense of an "if" statement in the function
sync_rcu_exp_select_cpus().
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

kernel/rcu/tree.c

@@ -3716,24 +3716,22 @@ static void sync_rcu_exp_select_cpus(struct rcu_state *rsp,
 			ret = smp_call_function_single(cpu, func, rsp, 0);
 			if (!ret) {
 				mask_ofl_ipi &= ~mask;
-			} else {
-				/* Failed, raced with offline. */
-				raw_spin_lock_irqsave_rcu_node(rnp, flags);
-				if (cpu_online(cpu) &&
-				    (rnp->expmask & mask)) {
-					raw_spin_unlock_irqrestore(&rnp->lock,
-								   flags);
-					schedule_timeout_uninterruptible(1);
-					if (cpu_online(cpu) &&
-					    (rnp->expmask & mask))
-						goto retry_ipi;
-					raw_spin_lock_irqsave_rcu_node(rnp,
-								       flags);
-				}
-				if (!(rnp->expmask & mask))
-					mask_ofl_ipi &= ~mask;
+				continue;
+			}
+			/* Failed, raced with offline. */
+			raw_spin_lock_irqsave_rcu_node(rnp, flags);
+			if (cpu_online(cpu) &&
+			    (rnp->expmask & mask)) {
 				raw_spin_unlock_irqrestore(&rnp->lock, flags);
+				schedule_timeout_uninterruptible(1);
+				if (cpu_online(cpu) &&
+				    (rnp->expmask & mask))
+					goto retry_ipi;
+				raw_spin_lock_irqsave_rcu_node(rnp, flags);
 			}
+			if (!(rnp->expmask & mask))
+				mask_ofl_ipi &= ~mask;
+			raw_spin_unlock_irqrestore(&rnp->lock, flags);
 		}
 		/* Report quiescent states for those that went offline. */
 		mask_ofl_test |= mask_ofl_ipi;