root/include/linux/topology.h

INCLUDED FROM

DEFINITIONS

1. numa_node_id
2. cpu_to_node
3. set_numa_node
4. set_cpu_numa_node
5. numa_node_id
6. set_numa_mem
7. node_to_mem_node
8. numa_mem_id
9. cpu_to_mem
10. set_cpu_numa_mem
11. numa_mem_id
12. node_to_mem_node
13. cpu_to_mem
14. cpu_smt_mask
15. cpu_cpu_mask

   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/arch_topology.h>
  31 #include <linux/cpumask.h>
  32 #include <linux/bitops.h>
  33 #include <linux/mmzone.h>
  34 #include <linux/smp.h>
  35 #include <linux/percpu.h>
  36 #include <asm/topology.h>
  37 
  38 #ifndef nr_cpus_node
  39 #define nr_cpus_node(node) cpumask_weight(cpumask_of_node(node))
  40 #endif
  41 
  42 #define for_each_node_with_cpus(node)                   \
  43         for_each_online_node(node)                      \
  44                 if (nr_cpus_node(node))
  45 
  46 int arch_update_cpu_topology(void);
  47 
  48 /* Conform to ACPI 2.0 SLIT distance definitions */
  49 #define LOCAL_DISTANCE          10
  50 #define REMOTE_DISTANCE         20
  51 #ifndef node_distance
  52 #define node_distance(from,to)  ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
  53 #endif
  54 #ifndef RECLAIM_DISTANCE
  55 /*
  56  * If the distance between nodes in a system is larger than RECLAIM_DISTANCE
  57  * (in whatever arch specific measurement units returned by node_distance())
  58  * and node_reclaim_mode is enabled then the VM will only call node_reclaim()
  59  * on nodes within this distance.
  60  */
  61 #define RECLAIM_DISTANCE 30
  62 #endif
  63 
  64 /*
  65  * The following tunable allows platforms to override the default node
  66  * reclaim distance (RECLAIM_DISTANCE) if remote memory accesses are
  67  * sufficiently fast that the default value actually hurts
  68  * performance.
  69  *
  70  * AMD EPYC machines use this because even though the 2-hop distance
  71  * is 32 (3.2x slower than a local memory access) performance actually
  72  * *improves* if allowed to reclaim memory and load balance tasks
  73  * between NUMA nodes 2-hops apart.
  74  */
  75 extern int __read_mostly node_reclaim_distance;
  76 
  77 #ifndef PENALTY_FOR_NODE_WITH_CPUS
  78 #define PENALTY_FOR_NODE_WITH_CPUS      (1)
  79 #endif
  80 
  81 #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
  82 DECLARE_PER_CPU(int, numa_node);
  83 
  84 #ifndef numa_node_id
  85 /* Returns the number of the current Node. */
  86 static inline int numa_node_id(void)
  87 {
  88         return raw_cpu_read(numa_node);
  89 }
  90 #endif
  91 
  92 #ifndef cpu_to_node
  93 static inline int cpu_to_node(int cpu)
  94 {
  95         return per_cpu(numa_node, cpu);
  96 }
  97 #endif
  98 
  99 #ifndef set_numa_node
 100 static inline void set_numa_node(int node)
 101 {
 102         this_cpu_write(numa_node, node);
 103 }
 104 #endif
 105 
 106 #ifndef set_cpu_numa_node
 107 static inline void set_cpu_numa_node(int cpu, int node)
 108 {
 109         per_cpu(numa_node, cpu) = node;
 110 }
 111 #endif
 112 
 113 #else   /* !CONFIG_USE_PERCPU_NUMA_NODE_ID */
 114 
 115 /* Returns the number of the current Node. */
 116 #ifndef numa_node_id
 117 static inline int numa_node_id(void)
 118 {
 119         return cpu_to_node(raw_smp_processor_id());
 120 }
 121 #endif
 122 
 123 #endif  /* [!]CONFIG_USE_PERCPU_NUMA_NODE_ID */
 124 
 125 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
 126 
 127 /*
 128  * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
 129  * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
 130  * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem().
 131  */
 132 DECLARE_PER_CPU(int, _numa_mem_);
 133 extern int _node_numa_mem_[MAX_NUMNODES];
 134 
 135 #ifndef set_numa_mem
 136 static inline void set_numa_mem(int node)
 137 {
 138         this_cpu_write(_numa_mem_, node);
 139         _node_numa_mem_[numa_node_id()] = node;
 140 }
 141 #endif
 142 
 143 #ifndef node_to_mem_node
 144 static inline int node_to_mem_node(int node)
 145 {
 146         return _node_numa_mem_[node];
 147 }
 148 #endif
 149 
 150 #ifndef numa_mem_id
 151 /* Returns the number of the nearest Node with memory */
 152 static inline int numa_mem_id(void)
 153 {
 154         return raw_cpu_read(_numa_mem_);
 155 }
 156 #endif
 157 
 158 #ifndef cpu_to_mem
 159 static inline int cpu_to_mem(int cpu)
 160 {
 161         return per_cpu(_numa_mem_, cpu);
 162 }
 163 #endif
 164 
 165 #ifndef set_cpu_numa_mem
 166 static inline void set_cpu_numa_mem(int cpu, int node)
 167 {
 168         per_cpu(_numa_mem_, cpu) = node;
 169         _node_numa_mem_[cpu_to_node(cpu)] = node;
 170 }
 171 #endif
 172 
 173 #else   /* !CONFIG_HAVE_MEMORYLESS_NODES */
 174 
 175 #ifndef numa_mem_id
 176 /* Returns the number of the nearest Node with memory */
 177 static inline int numa_mem_id(void)
 178 {
 179         return numa_node_id();
 180 }
 181 #endif
 182 
 183 #ifndef node_to_mem_node
 184 static inline int node_to_mem_node(int node)
 185 {
 186         return node;
 187 }
 188 #endif
 189 
 190 #ifndef cpu_to_mem
 191 static inline int cpu_to_mem(int cpu)
 192 {
 193         return cpu_to_node(cpu);
 194 }
 195 #endif
 196 
 197 #endif  /* [!]CONFIG_HAVE_MEMORYLESS_NODES */
 198 
 199 #ifndef topology_physical_package_id
 200 #define topology_physical_package_id(cpu)       ((void)(cpu), -1)
 201 #endif
 202 #ifndef topology_die_id
 203 #define topology_die_id(cpu)                    ((void)(cpu), -1)
 204 #endif
 205 #ifndef topology_core_id
 206 #define topology_core_id(cpu)                   ((void)(cpu), 0)
 207 #endif
 208 #ifndef topology_sibling_cpumask
 209 #define topology_sibling_cpumask(cpu)           cpumask_of(cpu)
 210 #endif
 211 #ifndef topology_core_cpumask
 212 #define topology_core_cpumask(cpu)              cpumask_of(cpu)
 213 #endif
 214 #ifndef topology_die_cpumask
 215 #define topology_die_cpumask(cpu)               cpumask_of(cpu)
 216 #endif
 217 
 218 #ifdef CONFIG_SCHED_SMT
 219 static inline const struct cpumask *cpu_smt_mask(int cpu)
 220 {
 221         return topology_sibling_cpumask(cpu);
 222 }
 223 #endif
 224 
 225 static inline const struct cpumask *cpu_cpu_mask(int cpu)
 226 {
 227         return cpumask_of_node(cpu_to_node(cpu));
 228 }
 229 
 230 
 231 #endif /* _LINUX_TOPOLOGY_H */