include/linux/topology.h

   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 nr_cpus_node
  38 #define nr_cpus_node(node) cpumask_weight(cpumask_of_node(node))
  39 #endif
  40
  41 #define for_each_node_with_cpus(node)                   \
  42         for_each_online_node(node)                      \
  43                 if (nr_cpus_node(node))
  44
  45 int arch_update_cpu_topology(void);
  46
  47 /* Conform to ACPI 2.0 SLIT distance definitions */
  48 #define LOCAL_DISTANCE          10
  49 #define REMOTE_DISTANCE         20
  50 #ifndef node_distance
  51 #define node_distance(from,to)  ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
  52 #endif
  53 #ifndef RECLAIM_DISTANCE
  54 /*
  55  * If the distance between nodes in a system is larger than RECLAIM_DISTANCE
  56  * (in whatever arch specific measurement units returned by node_distance())
  57  * and zone_reclaim_mode is enabled then the VM will only call zone_reclaim()
  58  * on nodes within this distance.
  59  */
  60 #define RECLAIM_DISTANCE 30
  61 #endif
  62 #ifndef PENALTY_FOR_NODE_WITH_CPUS
  63 #define PENALTY_FOR_NODE_WITH_CPUS      (1)
  64 #endif
  65
  66 #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
  67 DECLARE_PER_CPU(int, numa_node);
  68
  69 #ifndef numa_node_id
  70 /* Returns the number of the current Node. */
  71 static inline int numa_node_id(void)
  72 {
  73         return raw_cpu_read(numa_node);
  74 }
  75 #endif
  76
  77 #ifndef cpu_to_node
  78 static inline int cpu_to_node(int cpu)
  79 {
  80         return per_cpu(numa_node, cpu);
  81 }
  82 #endif
  83
  84 #ifndef set_numa_node
  85 static inline void set_numa_node(int node)
  86 {
  87         this_cpu_write(numa_node, node);
  88 }
  89 #endif
  90
  91 #ifndef set_cpu_numa_node
  92 static inline void set_cpu_numa_node(int cpu, int node)
  93 {
  94         per_cpu(numa_node, cpu) = node;
  95 }
  96 #endif
  97
  98 #else   /* !CONFIG_USE_PERCPU_NUMA_NODE_ID */
  99
 100 /* Returns the number of the current Node. */
 101 #ifndef numa_node_id
 102 static inline int numa_node_id(void)
 103 {
 104         return cpu_to_node(raw_smp_processor_id());
 105 }
 106 #endif
 107
 108 #endif  /* [!]CONFIG_USE_PERCPU_NUMA_NODE_ID */
 109
 110 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
 111
 112 /*
 113  * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
 114  * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
 115  * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem().
 116  */
 117 DECLARE_PER_CPU(int, _numa_mem_);
 118 extern int _node_numa_mem_[MAX_NUMNODES];
 119
 120 #ifndef set_numa_mem
 121 static inline void set_numa_mem(int node)
 122 {
 123         this_cpu_write(_numa_mem_, node);
 124         _node_numa_mem_[numa_node_id()] = node;
 125 }
 126 #endif
 127
 128 #ifndef node_to_mem_node
 129 static inline int node_to_mem_node(int node)
 130 {
 131         return _node_numa_mem_[node];
 132 }
 133 #endif
 134
 135 #ifndef numa_mem_id
 136 /* Returns the number of the nearest Node with memory */
 137 static inline int numa_mem_id(void)
 138 {
 139         return raw_cpu_read(_numa_mem_);
 140 }
 141 #endif
 142
 143 #ifndef cpu_to_mem
 144 static inline int cpu_to_mem(int cpu)
 145 {
 146         return per_cpu(_numa_mem_, cpu);
 147 }
 148 #endif
 149
 150 #ifndef set_cpu_numa_mem
 151 static inline void set_cpu_numa_mem(int cpu, int node)
 152 {
 153         per_cpu(_numa_mem_, cpu) = node;
 154         _node_numa_mem_[cpu_to_node(cpu)] = node;
 155 }
 156 #endif
 157
 158 #else   /* !CONFIG_HAVE_MEMORYLESS_NODES */
 159
 160 #ifndef numa_mem_id
 161 /* Returns the number of the nearest Node with memory */
 162 static inline int numa_mem_id(void)
 163 {
 164         return numa_node_id();
 165 }
 166 #endif
 167
 168 #ifndef node_to_mem_node
 169 static inline int node_to_mem_node(int node)
 170 {
 171         return node;
 172 }
 173 #endif
 174
 175 #ifndef cpu_to_mem
 176 static inline int cpu_to_mem(int cpu)
 177 {
 178         return cpu_to_node(cpu);
 179 }
 180 #endif
 181
 182 #endif  /* [!]CONFIG_HAVE_MEMORYLESS_NODES */
 183
 184 #ifndef topology_physical_package_id
 185 #define topology_physical_package_id(cpu)       ((void)(cpu), -1)
 186 #endif
 187 #ifndef topology_core_id
 188 #define topology_core_id(cpu)                   ((void)(cpu), 0)
 189 #endif
 190 #ifndef topology_sibling_cpumask
 191 #define topology_sibling_cpumask(cpu)           cpumask_of(cpu)
 192 #endif
 193 #ifndef topology_core_cpumask
 194 #define topology_core_cpumask(cpu)              cpumask_of(cpu)
 195 #endif
 196
 197 #ifdef CONFIG_SCHED_SMT
 198 static inline const struct cpumask *cpu_smt_mask(int cpu)
 199 {
 200         return topology_sibling_cpumask(cpu);
 201 }
 202 #endif
 203
 204 static inline const struct cpumask *cpu_cpu_mask(int cpu)
 205 {
 206         return cpumask_of_node(cpu_to_node(cpu));
 207 }
 208
 209
 210 #endif /* _LINUX_TOPOLOGY_H */