2 * include/linux/topology.h
4 * Written by: Matthew Dobson, IBM Corporation
6 * Copyright (C) 2002, IBM Corp.
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.
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
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.
25 * Send feedback to <colpatch@us.ibm.com>
27 #ifndef _LINUX_TOPOLOGY_H
28 #define _LINUX_TOPOLOGY_H
30 #include <linux/cpumask.h>
31 #include <linux/bitops.h>
32 #include <linux/mmzone.h>
33 #include <linux/smp.h>
34 #include <asm/topology.h>
36 #ifndef node_has_online_mem
37 #define node_has_online_mem(nid) (1)
41 #define nr_cpus_node(node) cpumask_weight(cpumask_of_node(node))
44 #define for_each_node_with_cpus(node) \
45 for_each_online_node(node) \
46 if (nr_cpus_node(node))
48 int arch_update_cpu_topology(void);
50 /* Conform to ACPI 2.0 SLIT distance definitions */
51 #define LOCAL_DISTANCE 10
52 #define REMOTE_DISTANCE 20
54 #define node_distance(from,to) ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
56 #ifndef RECLAIM_DISTANCE
58 * If the distance between nodes in a system is larger than RECLAIM_DISTANCE
59 * (in whatever arch specific measurement units returned by node_distance())
60 * then switch on zone reclaim on boot.
62 #define RECLAIM_DISTANCE 20
64 #ifndef PENALTY_FOR_NODE_WITH_CPUS
65 #define PENALTY_FOR_NODE_WITH_CPUS (1)
69 * Below are the 3 major initializers used in building sched_domains:
70 * SD_SIBLING_INIT, for SMT domains
71 * SD_CPU_INIT, for SMP domains
72 * SD_NODE_INIT, for NUMA domains
74 * Any architecture that cares to do any tuning to these values should do so
75 * by defining their own arch-specific initializer in include/asm/topology.h.
76 * A definition there will automagically override these default initializers
77 * and allow arch-specific performance tuning of sched_domains.
78 * (Only non-zero and non-null fields need be specified.)
81 #ifdef CONFIG_SCHED_SMT
82 /* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
83 * so can't we drop this in favor of CONFIG_SCHED_SMT?
85 #define ARCH_HAS_SCHED_WAKE_IDLE
86 /* Common values for SMT siblings */
87 #ifndef SD_SIBLING_INIT
88 #define SD_SIBLING_INIT (struct sched_domain) { \
92 .imbalance_pct = 110, \
93 .flags = SD_LOAD_BALANCE \
94 | SD_BALANCE_NEWIDLE \
99 | SD_SHARE_CPUPOWER, \
100 .last_balance = jiffies, \
101 .balance_interval = 1, \
102 .smt_gain = 1178, /* 15% */ \
105 #endif /* CONFIG_SCHED_SMT */
107 #ifdef CONFIG_SCHED_MC
108 /* Common values for MC siblings. for now mostly derived from SD_CPU_INIT */
110 #define SD_MC_INIT (struct sched_domain) { \
114 .imbalance_pct = 125, \
115 .cache_nice_tries = 1, \
119 .flags = SD_LOAD_BALANCE \
124 | SD_SHARE_PKG_RESOURCES\
125 | sd_balance_for_mc_power()\
126 | sd_power_saving_flags(),\
127 .last_balance = jiffies, \
128 .balance_interval = 1, \
131 #endif /* CONFIG_SCHED_MC */
133 /* Common values for CPUs */
135 #define SD_CPU_INIT (struct sched_domain) { \
139 .imbalance_pct = 125, \
140 .cache_nice_tries = 1, \
146 .flags = SD_LOAD_BALANCE \
151 | sd_balance_for_package_power()\
152 | sd_power_saving_flags(),\
153 .last_balance = jiffies, \
154 .balance_interval = 1, \
158 /* sched_domains SD_ALLNODES_INIT for NUMA machines */
159 #define SD_ALLNODES_INIT (struct sched_domain) { \
160 .min_interval = 64, \
161 .max_interval = 64*num_online_cpus(), \
162 .busy_factor = 128, \
163 .imbalance_pct = 133, \
164 .cache_nice_tries = 1, \
167 .flags = SD_LOAD_BALANCE \
168 | SD_BALANCE_NEWIDLE \
171 .last_balance = jiffies, \
172 .balance_interval = 64, \
177 #error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!!
179 #endif /* CONFIG_NUMA */
181 #ifndef topology_physical_package_id
182 #define topology_physical_package_id(cpu) ((void)(cpu), -1)
184 #ifndef topology_core_id
185 #define topology_core_id(cpu) ((void)(cpu), 0)
187 #ifndef topology_thread_siblings
188 #define topology_thread_siblings(cpu) cpumask_of_cpu(cpu)
190 #ifndef topology_core_siblings
191 #define topology_core_siblings(cpu) cpumask_of_cpu(cpu)
193 #ifndef topology_thread_cpumask
194 #define topology_thread_cpumask(cpu) cpumask_of(cpu)
196 #ifndef topology_core_cpumask
197 #define topology_core_cpumask(cpu) cpumask_of(cpu)
200 /* Returns the number of the current Node. */
202 #define numa_node_id() (cpu_to_node(raw_smp_processor_id()))
205 #endif /* _LINUX_TOPOLOGY_H */