cpumask: convert drivers/idle/i7300_idle.c to cpumask_var_t

Fairly simple transformation:
1) cpumask_t -> cpumask_var_t and alloc_cpumask_var/free_cpumask_var
   (which are a NOOP unless CONFIG_CPUMASK_OFFSTACK=y).
2) cpu_set -> cpumask_set_cpu
3) cpus_weight -> cpumask_weight
4) cpu_clear -> cpumask_clear_cpu

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
To: Andy Henroid <andrew.d.henroid@intel.com>

drivers/idle/i7300_idle.c

@@ -81,7 +81,7 @@ static u8 i7300_idle_thrtctl_saved;
 static u8 i7300_idle_thrtlow_saved;
 static u32 i7300_idle_mc_saved;
 
-static cpumask_t idle_cpumask;
+static cpumask_var_t idle_cpumask;
 static ktime_t start_ktime;
 static unsigned long avg_idle_us;
 
@@ -459,9 +459,9 @@ static int i7300_idle_notifier(struct notifier_block *nb, unsigned long val,
 	spin_lock_irqsave(&i7300_idle_lock, flags);
 	if (val == IDLE_START) {
 
-		cpu_set(smp_processor_id(), idle_cpumask);
+		cpumask_set_cpu(smp_processor_id(), idle_cpumask);
 
-		if (cpus_weight(idle_cpumask) != num_online_cpus())
+		if (cpumask_weight(idle_cpumask) != num_online_cpus())
 			goto end;
 
 		now_ktime = ktime_get();
@@ -478,8 +478,8 @@ static int i7300_idle_notifier(struct notifier_block *nb, unsigned long val,
 		i7300_idle_ioat_start();
 
 	} else if (val == IDLE_END) {
-		cpu_clear(smp_processor_id(), idle_cpumask);
-		if (cpus_weight(idle_cpumask) == (num_online_cpus() - 1)) {
+		cpumask_clear_cpu(smp_processor_id(), idle_cpumask);
+		if (cpumask_weight(idle_cpumask) == (num_online_cpus() - 1)) {
 			/* First CPU coming out of idle */
 			u64 idle_duration_us;
 
@@ -553,7 +553,6 @@ struct debugfs_file_info {
 static int __init i7300_idle_init(void)
 {
 	spin_lock_init(&i7300_idle_lock);
-	cpus_clear(idle_cpumask);
 	total_us = 0;
 
 	if (i7300_idle_platform_probe(&fbd_dev, &ioat_dev, forceload))
@@ -565,6 +564,9 @@ static int __init i7300_idle_init(void)
 	if (i7300_idle_ioat_init())
 		return -ENODEV;
 
+	if (!zalloc_cpumask_var(&idle_cpumask, GFP_KERNEL))
+		return -ENOMEM;
+
 	debugfs_dir = debugfs_create_dir("i7300_idle", NULL);
 	if (debugfs_dir) {
 		int i = 0;
@@ -589,6 +591,7 @@ static int __init i7300_idle_init(void)
 static void __exit i7300_idle_exit(void)
 {
 	idle_notifier_unregister(&i7300_idle_nb);
+	free_cpumask_var(idle_cpumask);
 
 	if (debugfs_dir) {
 		int i = 0;