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
27 u16 cpu_to_node_map[NR_CPUS] __cacheline_aligned;
28 EXPORT_SYMBOL(cpu_to_node_map);
29
30 cpumask_t node_to_cpu_mask[MAX_NUMNODES] __cacheline_aligned;
31 EXPORT_SYMBOL(node_to_cpu_mask);
32
map_cpu_to_node(int cpu,int nid)33 void 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 (cpu_isset(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 cpu_set(cpu, node_to_cpu_mask[nid]);
51 return;
52 }
53
unmap_cpu_from_node(int cpu,int nid)54 void unmap_cpu_from_node(int cpu, int nid)
55 {
56 WARN_ON(!cpu_isset(cpu, node_to_cpu_mask[nid]));
57 WARN_ON(cpu_to_node_map[cpu] != nid);
58 cpu_to_node_map[cpu] = 0;
59 cpu_clear(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 */
build_cpu_to_node_map(void)69 void __init build_cpu_to_node_map(void)
70 {
71 int cpu, i, node;
72
73 for(node=0; node < MAX_NUMNODES; node++)
74 cpus_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