Commit c38da569 authored by Rusty Russell's avatar Rusty Russell Committed by Ingo Molnar
Browse files

x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus 



Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y

Part of the "getting rid of obsolete cpumask_t" patch:

 1) Use cpumask_var_t: this is a pointer if CONFIG_CPUMASK_OFFSTACK=y
 2) Call alloc_cpumask_var() on first entry into enter_uniprocessor()
 3) Use modern cpumask_* functions.

Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
Cc: Pekka Paalanen <pq@iki.fi>
LKML-Reference: <200903111633.55952.rusty@rustcorp.com.au>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 89bd55d1

arch/x86/mm/mmio-mod.c

+13 −6
Original line number Diff line number Diff line
@@ -378,27 +378,34 @@ static void clear_trace_list(void) 
}



#ifdef CONFIG_HOTPLUG_CPU

static cpumask_t downed_cpus;

static cpumask_var_t downed_cpus;



static void enter_uniprocessor(void)

{

	int cpu;

	int err;



	if (downed_cpus == NULL &&

	    !alloc_cpumask_var(&downed_cpus, GFP_KERNEL)) {

		pr_notice(NAME "Failed to allocate mask\n");

		goto out;

	}



	get_online_cpus();

	downed_cpus = cpu_online_map;

	cpu_clear(first_cpu(cpu_online_map), downed_cpus);

	cpumask_copy(downed_cpus, cpu_online_mask);

	cpumask_clear_cpu(cpumask_first(cpu_online_mask), downed_cpus);

	if (num_online_cpus() > 1)

		pr_notice(NAME "Disabling non-boot CPUs...\n");

	put_online_cpus();



	for_each_cpu_mask(cpu, downed_cpus) {

	for_each_cpu(cpu, downed_cpus) {

		err = cpu_down(cpu);

		if (!err)

			pr_info(NAME "CPU%d is down.\n", cpu);

		else

			pr_err(NAME "Error taking CPU%d down: %d\n", cpu, err);

	}

out:

	if (num_online_cpus() > 1)

		pr_warning(NAME "multiple CPUs still online, "

						"may miss events.\n");
@@ -411,10 +418,10 @@ static void __ref leave_uniprocessor(void) 
	int cpu;

	int err;



	if (cpus_weight(downed_cpus) == 0)

	if (downed_cpus == NULL || cpumask_weight(downed_cpus) == 0)

		return;

	pr_notice(NAME "Re-enabling CPUs...\n");

	for_each_cpu_mask(cpu, downed_cpus) {

	for_each_cpu(cpu, downed_cpus) {

		err = cpu_up(cpu);

		if (!err)

			pr_info(NAME "enabled CPU%d.\n", cpu);

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