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 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
  49 int 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
  71 DECLARE_PER_CPU(int, numa_node);
  72
  73 #ifndef numa_node_id
  74 /* Returns the number of the current Node. */
  75 static inline int numa_node_id(void)
  76 {
  77         return raw_cpu_read(numa_node);
  78 }
  79 #endif
  80
  81 #ifndef cpu_to_node
  82 static inline int cpu_to_node(int cpu)
  83 {
  84         return per_cpu(numa_node, cpu);
  85 }
  86 #endif
  87
  88 #ifndef set_numa_node
  89 static 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
  96 static 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
 106 static 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  */
 121 DECLARE_PER_CPU(int, _numa_mem_);
 122 extern int _node_numa_mem_[MAX_NUMNODES];
 123
 124 #ifndef set_numa_mem
 125 static 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
 133 static 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 */
 141 static inline int numa_mem_id(void)
 142 {
 143         return raw_cpu_read(_numa_mem_);
 144 }
 145 #endif
 146
 147 #ifndef cpu_to_mem
 148 static 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
 155 static 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 */
 166 static inline int numa_mem_id(void)
 167 {
 168         return numa_node_id();
 169 }
 170 #endif
 171
 172 #ifndef node_to_mem_node
 173 static inline int node_to_mem_node(int node)
 174 {
 175         return node;
 176 }
 177 #endif
 178
 179 #ifndef cpu_to_mem
 180 static 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
 202 static inline const struct cpumask *cpu_smt_mask(int cpu)
 203 {
 204         return topology_thread_cpumask(cpu);
 205 }
 206 #endif
 207
 208 static 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 */