Re: [PATCH 3/5] cpumask: convert misc driver functions

[Rusty Russell <rusty@rustcorp.com.au>]

On Thursday 08 January 2009 06:28:35 Mike Travis wrote:
> From: Rusty Russell <rusty@rustcorp.com.au>
> 
> Impact: use new cpumask API.
> 
> Convert misc driver functions to use struct cpumask.
...
> @@ -593,15 +592,20 @@ static int __cpuinit iucv_cpu_notify(str
>  		break;
>  	case CPU_DOWN_PREPARE:
>  	case CPU_DOWN_PREPARE_FROZEN:
> -		cpumask = iucv_buffer_cpumask;
> -		cpu_clear(cpu, cpumask);
> -		if (cpus_empty(cpumask))
> +		if (!alloc_cpumask_var(&cpumask, GFP_KERNEL))
> +			return NOTIFY_BAD;
> +		cpumask_copy(cpumask, &iucv_buffer_cpumask);
> +		cpumask_clear_cpu(cpu, cpumask);
> +		if (cpumask_empty(cpumask)) {
>  			/* Can't offline last IUCV enabled cpu. */
> +			free_cpumask_var(cpumask);
>  			return NOTIFY_BAD;
> +		}
>  		smp_call_function_single(cpu, iucv_retrieve_cpu, NULL, 1);
>  		if (cpus_empty(iucv_irq_cpumask))
>  			smp_call_function_single(first_cpu(iucv_buffer_cpumask),
>  						 iucv_allow_cpu, NULL, 1);
> +		free_cpumask_var(cpumask);
>  		break;

Minor nit: this can be done better, actually:

@@ -596,9 +594,7 @@ static int __cpuinit iucv_cpu_notify(str
 	case CPU_DOWN_PREPARE_FROZEN:
 		if (!iucv_path_table)
 			break;
-		cpumask = iucv_buffer_cpumask;
-		cpu_clear(cpu, cpumask);
-		if (cpus_empty(cpumask))
+		if (cpumask_any_but(&iucv_buffer_cpumask, cpu) >= nr_cpu_ids)
 			/* Can't offline last IUCV enabled cpu. */
 			return NOTIFY_BAD;
 		smp_call_function_single(cpu, iucv_retrieve_cpu, NULL, 1);

Cheers,
Rusty.