1/*
2 * include/linux/topology.h
3 *
4 * Written by: Matthew Dobson, IBM Corporation
5 *
6 * Copyright (C) 2002, IBM Corp.
7 *
8 * All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
18 * NON INFRINGEMENT.  See the GNU General Public License for more
19 * details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 *
25 * Send feedback to <colpatch@us.ibm.com>
26 */
27#ifndef _LINUX_TOPOLOGY_H
28#define _LINUX_TOPOLOGY_H
29
30#include <linux/cpumask.h>
31#include <linux/bitops.h>
32#include <linux/mmzone.h>
33#include <linux/smp.h>
34#include <linux/percpu.h>
35#include <asm/topology.h>
36
37#ifndef node_has_online_mem
38#define node_has_online_mem(nid) (1)
39#endif
40
41#ifndef nr_cpus_node
42#define nr_cpus_node(node) cpumask_weight(cpumask_of_node(node))
43#endif
44
45#define for_each_node_with_cpus(node)			\
46	for_each_online_node(node)			\
47		if (nr_cpus_node(node))
48
49int arch_update_cpu_topology(void);
50
51/* Conform to ACPI 2.0 SLIT distance definitions */
52#define LOCAL_DISTANCE		10
53#define REMOTE_DISTANCE		20
54#ifndef node_distance
55#define node_distance(from,to)	((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
56#endif
57#ifndef RECLAIM_DISTANCE
58/*
59 * If the distance between nodes in a system is larger than RECLAIM_DISTANCE
60 * (in whatever arch specific measurement units returned by node_distance())
61 * and zone_reclaim_mode is enabled then the VM will only call zone_reclaim()
62 * on nodes within this distance.
63 */
64#define RECLAIM_DISTANCE 30
65#endif
66#ifndef PENALTY_FOR_NODE_WITH_CPUS
67#define PENALTY_FOR_NODE_WITH_CPUS	(1)
68#endif
69
70#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
71DECLARE_PER_CPU(int, numa_node);
72
73#ifndef numa_node_id
74/* Returns the number of the current Node. */
75static inline int numa_node_id(void)
76{
77	return raw_cpu_read(numa_node);
78}
79#endif
80
81#ifndef cpu_to_node
82static inline int cpu_to_node(int cpu)
83{
84	return per_cpu(numa_node, cpu);
85}
86#endif
87
88#ifndef set_numa_node
89static inline void set_numa_node(int node)
90{
91	this_cpu_write(numa_node, node);
92}
93#endif
94
95#ifndef set_cpu_numa_node
96static inline void set_cpu_numa_node(int cpu, int node)
97{
98	per_cpu(numa_node, cpu) = node;
99}
100#endif
101
102#else	/* !CONFIG_USE_PERCPU_NUMA_NODE_ID */
103
104/* Returns the number of the current Node. */
105#ifndef numa_node_id
106static inline int numa_node_id(void)
107{
108	return cpu_to_node(raw_smp_processor_id());
109}
110#endif
111
112#endif	/* [!]CONFIG_USE_PERCPU_NUMA_NODE_ID */
113
114#ifdef CONFIG_HAVE_MEMORYLESS_NODES
115
116/*
117 * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
118 * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
119 * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem().
120 */
121DECLARE_PER_CPU(int, _numa_mem_);
122extern int _node_numa_mem_[MAX_NUMNODES];
123
124#ifndef set_numa_mem
125static inline void set_numa_mem(int node)
126{
127	this_cpu_write(_numa_mem_, node);
128	_node_numa_mem_[numa_node_id()] = node;
129}
130#endif
131
132#ifndef node_to_mem_node
133static inline int node_to_mem_node(int node)
134{
135	return _node_numa_mem_[node];
136}
137#endif
138
139#ifndef numa_mem_id
140/* Returns the number of the nearest Node with memory */
141static inline int numa_mem_id(void)
142{
143	return raw_cpu_read(_numa_mem_);
144}
145#endif
146
147#ifndef cpu_to_mem
148static inline int cpu_to_mem(int cpu)
149{
150	return per_cpu(_numa_mem_, cpu);
151}
152#endif
153
154#ifndef set_cpu_numa_mem
155static inline void set_cpu_numa_mem(int cpu, int node)
156{
157	per_cpu(_numa_mem_, cpu) = node;
158	_node_numa_mem_[cpu_to_node(cpu)] = node;
159}
160#endif
161
162#else	/* !CONFIG_HAVE_MEMORYLESS_NODES */
163
164#ifndef numa_mem_id
165/* Returns the number of the nearest Node with memory */
166static inline int numa_mem_id(void)
167{
168	return numa_node_id();
169}
170#endif
171
172#ifndef node_to_mem_node
173static inline int node_to_mem_node(int node)
174{
175	return node;
176}
177#endif
178
179#ifndef cpu_to_mem
180static inline int cpu_to_mem(int cpu)
181{
182	return cpu_to_node(cpu);
183}
184#endif
185
186#endif	/* [!]CONFIG_HAVE_MEMORYLESS_NODES */
187
188#ifndef topology_physical_package_id
189#define topology_physical_package_id(cpu)	((void)(cpu), -1)
190#endif
191#ifndef topology_core_id
192#define topology_core_id(cpu)			((void)(cpu), 0)
193#endif
194#ifndef topology_thread_cpumask
195#define topology_thread_cpumask(cpu)		cpumask_of(cpu)
196#endif
197#ifndef topology_core_cpumask
198#define topology_core_cpumask(cpu)		cpumask_of(cpu)
199#endif
200
201#ifdef CONFIG_SCHED_SMT
202static inline const struct cpumask *cpu_smt_mask(int cpu)
203{
204	return topology_thread_cpumask(cpu);
205}
206#endif
207
208static inline const struct cpumask *cpu_cpu_mask(int cpu)
209{
210	return cpumask_of_node(cpu_to_node(cpu));
211}
212
213
214#endif /* _LINUX_TOPOLOGY_H */
215