cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c

  * Optimize various places where a pointer to the cpumask_of_cpu value
    will result in reducing stack pressure.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

lib/smp_processor_id.c

@@ -11,7 +11,7 @@ notrace unsigned int debug_smp_processor_id(void)
 {
 	unsigned long preempt_count = preempt_count();
 	int this_cpu = raw_smp_processor_id();
-	cpumask_t this_mask;
+	cpumask_of_cpu_ptr_declare(this_mask);
 
 	if (likely(preempt_count))
 		goto out;
@@ -23,9 +23,9 @@ notrace unsigned int debug_smp_processor_id(void)
 	 * Kernel threads bound to a single CPU can safely use
 	 * smp_processor_id():
 	 */
-	this_mask = cpumask_of_cpu(this_cpu);
+	cpumask_of_cpu_ptr_next(this_mask, cpu);
 
-	if (cpus_equal(current->cpus_allowed, this_mask))
+	if (cpus_equal(current->cpus_allowed, *this_mask))
 		goto out;
 
 	/*