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) \
43 node_to_cpumask_ptr(__tmp__, node); \
44 cpus_weight(*__tmp__); \
48 #define for_each_node_with_cpus(node) \
49 for_each_online_node(node) \
50 if (nr_cpus_node(node))
52 int arch_update_cpu_topology(void);
54 /* Conform to ACPI 2.0 SLIT distance definitions */
55 #define LOCAL_DISTANCE 10
56 #define REMOTE_DISTANCE 20
58 #define node_distance(from,to) ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
60 #ifndef RECLAIM_DISTANCE
62 * If the distance between nodes in a system is larger than RECLAIM_DISTANCE
63 * (in whatever arch specific measurement units returned by node_distance())
64 * then switch on zone reclaim on boot.
66 #define RECLAIM_DISTANCE 20
68 #ifndef PENALTY_FOR_NODE_WITH_CPUS
69 #define PENALTY_FOR_NODE_WITH_CPUS (1)
73 * Below are the 3 major initializers used in building sched_domains:
74 * SD_SIBLING_INIT, for SMT domains
75 * SD_CPU_INIT, for SMP domains
76 * SD_NODE_INIT, for NUMA domains
78 * Any architecture that cares to do any tuning to these values should do so
79 * by defining their own arch-specific initializer in include/asm/topology.h.
80 * A definition there will automagically override these default initializers
81 * and allow arch-specific performance tuning of sched_domains.
82 * (Only non-zero and non-null fields need be specified.)
85 #ifdef CONFIG_SCHED_SMT
86 /* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
87 * so can't we drop this in favor of CONFIG_SCHED_SMT?
89 #define ARCH_HAS_SCHED_WAKE_IDLE
90 /* Common values for SMT siblings */
91 #ifndef SD_SIBLING_INIT
92 #define SD_SIBLING_INIT (struct sched_domain) { \
96 .imbalance_pct = 110, \
97 .flags = SD_LOAD_BALANCE \
98 | SD_BALANCE_NEWIDLE \
103 | SD_SHARE_CPUPOWER, \
104 .last_balance = jiffies, \
105 .balance_interval = 1, \
108 #endif /* CONFIG_SCHED_SMT */
110 #ifdef CONFIG_SCHED_MC
111 /* Common values for MC siblings. for now mostly derived from SD_CPU_INIT */
113 #define SD_MC_INIT (struct sched_domain) { \
117 .imbalance_pct = 125, \
118 .cache_nice_tries = 1, \
122 .flags = SD_LOAD_BALANCE \
127 | SD_SHARE_PKG_RESOURCES\
128 | sd_balance_for_mc_power()\
129 | sd_power_saving_flags(),\
130 .last_balance = jiffies, \
131 .balance_interval = 1, \
134 #endif /* CONFIG_SCHED_MC */
136 /* Common values for CPUs */
138 #define SD_CPU_INIT (struct sched_domain) { \
142 .imbalance_pct = 125, \
143 .cache_nice_tries = 1, \
149 .flags = SD_LOAD_BALANCE \
154 | sd_balance_for_package_power()\
155 | sd_power_saving_flags(),\
156 .last_balance = jiffies, \
157 .balance_interval = 1, \
161 /* sched_domains SD_ALLNODES_INIT for NUMA machines */
162 #define SD_ALLNODES_INIT (struct sched_domain) { \
163 .min_interval = 64, \
164 .max_interval = 64*num_online_cpus(), \
165 .busy_factor = 128, \
166 .imbalance_pct = 133, \
167 .cache_nice_tries = 1, \
170 .flags = SD_LOAD_BALANCE \
171 | SD_BALANCE_NEWIDLE \
174 .last_balance = jiffies, \
175 .balance_interval = 64, \
180 #error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!!
182 #endif /* CONFIG_NUMA */
184 #ifndef topology_physical_package_id
185 #define topology_physical_package_id(cpu) ((void)(cpu), -1)
187 #ifndef topology_core_id
188 #define topology_core_id(cpu) ((void)(cpu), 0)
190 #ifndef topology_thread_siblings
191 #define topology_thread_siblings(cpu) cpumask_of_cpu(cpu)
193 #ifndef topology_core_siblings
194 #define topology_core_siblings(cpu) cpumask_of_cpu(cpu)
197 #endif /* _LINUX_TOPOLOGY_H */