linux/arch/x86/mm/numa.c

/* Common code for 32 and 64-bit NUMA */
#include <linux/topology.h>
#include <linux/module.h>
#include <linux/bootmem.h>
#include <asm/numa.h>
#include <asm/acpi.h>

int __initdata numa_off;

static __init int numa_setup(char *opt)
{
	if (!opt)
		return -EINVAL;
	if (!strncmp(opt, "off", 3))
		numa_off = 1;
#ifdef CONFIG_NUMA_EMU
	if (!strncmp(opt, "fake=", 5))
		numa_emu_cmdline(opt + 5);
#endif
#ifdef CONFIG_ACPI_NUMA
	if (!strncmp(opt, "noacpi", 6))
		acpi_numa = -1;
#endif
	return 0;
}
early_param("numa", numa_setup);

/*
 * apicid, cpu, node mappings
 */
s16 __apicid_to_node[MAX_LOCAL_APIC] __cpuinitdata = {
	[0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
};

cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
EXPORT_SYMBOL(node_to_cpumask_map);

/*
 * Map cpu index to node index
 */
#ifdef CONFIG_X86_32
DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, 0);
#else
DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
#endif
EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);

void __cpuinit numa_set_node(int cpu, int node)
{
	int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);

	/* early setting, no percpu area yet */
	if (cpu_to_node_map) {
		cpu_to_node_map[cpu] = node;
		return;
	}

#ifdef CONFIG_DEBUG_PER_CPU_MAPS
	if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) {
		printk(KERN_ERR "numa_set_node: invalid cpu# (%d)\n", cpu);
		dump_stack();
		return;
	}
#endif
	per_cpu(x86_cpu_to_node_map, cpu) = node;

	if (node != NUMA_NO_NODE)
		set_cpu_numa_node(cpu, node);
}

void __cpuinit numa_clear_node(int cpu)
{
	numa_set_node(cpu, NUMA_NO_NODE);
}

/*
 * Allocate node_to_cpumask_map based on number of available nodes
 * Requires node_possible_map to be valid.
 *
 * Note: node_to_cpumask() is not valid until after this is done.
 * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
 */
void __init setup_node_to_cpumask_map(void)
{
	unsigned int node, num = 0;

	/* setup nr_node_ids if not done yet */
	if (nr_node_ids == MAX_NUMNODES) {
		for_each_node_mask(node, node_possible_map)
			num = node;
		nr_node_ids = num + 1;
	}

	/* allocate the map */
	for (node = 0; node < nr_node_ids; node++)
		alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);

	/* cpumask_of_node() will now work */
	pr_debug("Node to cpumask map for %d nodes\n", nr_node_ids);
}

#ifdef CONFIG_DEBUG_PER_CPU_MAPS

int __cpu_to_node(int cpu)
{
	if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
		printk(KERN_WARNING
			"cpu_to_node(%d): usage too early!\n", cpu);
		dump_stack();
		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
	}
	return per_cpu(x86_cpu_to_node_map, cpu);
}
EXPORT_SYMBOL(__cpu_to_node);

/*
 * Same function as cpu_to_node() but used if called before the
 * per_cpu areas are setup.
 */
int early_cpu_to_node(int cpu)
{
	if (early_per_cpu_ptr(x86_cpu_to_node_map))
		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];

	if (!cpu_possible(cpu)) {
		printk(KERN_WARNING
			"early_cpu_to_node(%d): no per_cpu area!\n", cpu);
		dump_stack();
		return NUMA_NO_NODE;
	}
	return per_cpu(x86_cpu_to_node_map, cpu);
}

/*
 * Returns a pointer to the bitmask of CPUs on Node 'node'.
 */
const struct cpumask *cpumask_of_node(int node)
{
	if (node >= nr_node_ids) {
		printk(KERN_WARNING
			"cpumask_of_node(%d): node > nr_node_ids(%d)\n",
			node, nr_node_ids);
		dump_stack();
		return cpu_none_mask;
	}
	if (node_to_cpumask_map[node] == NULL) {
		printk(KERN_WARNING
			"cpumask_of_node(%d): no node_to_cpumask_map!\n",
			node);
		dump_stack();
		return cpu_online_mask;
	}
	return node_to_cpumask_map[node];
}
EXPORT_SYMBOL(cpumask_of_node);

#endif	/* CONFIG_DEBUG_PER_CPU_MAPS */