1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
15 *
16 * ia64 kernel NUMA specific stuff
17 *
18 * Copyright (C) 2002 Erich Focht <efocht@ess.nec.de>
19 * Copyright (C) 2004 Silicon Graphics, Inc.
20 *   Jesse Barnes <jbarnes@sgi.com>
21 */
22#include <linux/topology.h>
23#include <linux/module.h>
24#include <asm/processor.h>
25#include <asm/smp.h>
26
27u16 cpu_to_node_map[NR_CPUS] __cacheline_aligned;
28EXPORT_SYMBOL(cpu_to_node_map);
29
30cpumask_t node_to_cpu_mask[MAX_NUMNODES] __cacheline_aligned;
31EXPORT_SYMBOL(node_to_cpu_mask);
32
33void map_cpu_to_node(int cpu, int nid)
34{
35	int oldnid;
36	if (nid < 0) { /* just initialize by zero */
37		cpu_to_node_map[cpu] = 0;
38		return;
39	}
40	/* sanity check first */
41	oldnid = cpu_to_node_map[cpu];
42	if (cpumask_test_cpu(cpu, &node_to_cpu_mask[oldnid])) {
43		return; /* nothing to do */
44	}
45	/* we don't have cpu-driven node hot add yet...
46	   In usual case, node is created from SRAT at boot time. */
47	if (!node_online(nid))
48		nid = first_online_node;
49	cpu_to_node_map[cpu] = nid;
50	cpumask_set_cpu(cpu, &node_to_cpu_mask[nid]);
51	return;
52}
53
54void unmap_cpu_from_node(int cpu, int nid)
55{
56	WARN_ON(!cpumask_test_cpu(cpu, &node_to_cpu_mask[nid]));
57	WARN_ON(cpu_to_node_map[cpu] != nid);
58	cpu_to_node_map[cpu] = 0;
59	cpumask_clear_cpu(cpu, &node_to_cpu_mask[nid]);
60}
61
62
63/**
64 * build_cpu_to_node_map - setup cpu to node and node to cpumask arrays
65 *
66 * Build cpu to node mapping and initialize the per node cpu masks using
67 * info from the node_cpuid array handed to us by ACPI.
68 */
69void __init build_cpu_to_node_map(void)
70{
71	int cpu, i, node;
72
73	for(node=0; node < MAX_NUMNODES; node++)
74		cpumask_clear(&node_to_cpu_mask[node]);
75
76	for_each_possible_early_cpu(cpu) {
77		node = -1;
78		for (i = 0; i < NR_CPUS; ++i)
79			if (cpu_physical_id(cpu) == node_cpuid[i].phys_id) {
80				node = node_cpuid[i].nid;
81				break;
82			}
83		map_cpu_to_node(cpu, node);
84	}
85}
86