xref: /openbmc/linux/arch/ia64/kernel/numa.c (revision 8a84fc15ae5cafcc366dd85cf8e1ab2040679abc)
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 
32 void __cpuinit map_cpu_to_node(int cpu, int nid)
33 {
34 	int oldnid;
35 	if (nid < 0) { /* just initialize by zero */
36 		cpu_to_node_map[cpu] = 0;
37 		return;
38 	}
39 	/* sanity check first */
40 	oldnid = cpu_to_node_map[cpu];
41 	if (cpu_isset(cpu, node_to_cpu_mask[oldnid])) {
42 		return; /* nothing to do */
43 	}
44 	/* we don't have cpu-driven node hot add yet...
45 	   In usual case, node is created from SRAT at boot time. */
46 	if (!node_online(nid))
47 		nid = first_online_node;
48 	cpu_to_node_map[cpu] = nid;
49 	cpu_set(cpu, node_to_cpu_mask[nid]);
50 	return;
51 }
52 
53 void __cpuinit unmap_cpu_from_node(int cpu, int nid)
54 {
55 	WARN_ON(!cpu_isset(cpu, node_to_cpu_mask[nid]));
56 	WARN_ON(cpu_to_node_map[cpu] != nid);
57 	cpu_to_node_map[cpu] = 0;
58 	cpu_clear(cpu, node_to_cpu_mask[nid]);
59 }
60 
61 
62 /**
63  * build_cpu_to_node_map - setup cpu to node and node to cpumask arrays
64  *
65  * Build cpu to node mapping and initialize the per node cpu masks using
66  * info from the node_cpuid array handed to us by ACPI.
67  */
68 void __init build_cpu_to_node_map(void)
69 {
70 	int cpu, i, node;
71 
72 	for(node=0; node < MAX_NUMNODES; node++)
73 		cpus_clear(node_to_cpu_mask[node]);
74 
75 	for(cpu = 0; cpu < NR_CPUS; ++cpu) {
76 		node = -1;
77 		for (i = 0; i < NR_CPUS; ++i)
78 			if (cpu_physical_id(cpu) == node_cpuid[i].phys_id) {
79 				node = node_cpuid[i].nid;
80 				break;
81 			}
82 		map_cpu_to_node(cpu, node);
83 	}
84 }
85