rcu: use %*pb[l] to print bitmaps including cpumasks and nodemasks

printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kernel/rcu/tree_plugin.h

@@ -49,7 +49,6 @@ DEFINE_PER_CPU(char, rcu_cpu_has_work);
 static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */
 static bool have_rcu_nocb_mask;	    /* Was rcu_nocb_mask allocated? */
 static bool __read_mostly rcu_nocb_poll;    /* Offload kthread are to poll. */
-static char __initdata nocb_buf[NR_CPUS * 5];
 #endif /* #ifdef CONFIG_RCU_NOCB_CPU */
 
 /*
@@ -2386,8 +2385,8 @@ void __init rcu_init_nohz(void)
 		cpumask_and(rcu_nocb_mask, cpu_possible_mask,
 			    rcu_nocb_mask);
 	}
-	cpulist_scnprintf(nocb_buf, sizeof(nocb_buf), rcu_nocb_mask);
-	pr_info("\tOffload RCU callbacks from CPUs: %s.\n", nocb_buf);
+	pr_info("\tOffload RCU callbacks from CPUs: %*pbl.\n",
+		cpumask_pr_args(rcu_nocb_mask));
 	if (rcu_nocb_poll)
 		pr_info("\tPoll for callbacks from no-CBs CPUs.\n");