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) \
44 __tmp__ = node_to_cpumask(node); \
45 cpus_weight(__tmp__); \
49 #define for_each_node_with_cpus(node) \
50 for_each_online_node(node) \
51 if (nr_cpus_node(node))
54 /* Conform to ACPI 2.0 SLIT distance definitions */
55 #define LOCAL_DISTANCE 10
56 #define REMOTE_DISTANCE 20
57 #define node_distance(from,to) ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
59 #ifndef PENALTY_FOR_NODE_WITH_CPUS
60 #define PENALTY_FOR_NODE_WITH_CPUS (1)
64 * Below are the 3 major initializers used in building sched_domains:
65 * SD_SIBLING_INIT, for SMT domains
66 * SD_CPU_INIT, for SMP domains
67 * SD_NODE_INIT, for NUMA domains
69 * Any architecture that cares to do any tuning to these values should do so
70 * by defining their own arch-specific initializer in include/asm/topology.h.
71 * A definition there will automagically override these default initializers
72 * and allow arch-specific performance tuning of sched_domains.
74 #ifdef CONFIG_SCHED_SMT
75 /* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
76 * so can't we drop this in favor of CONFIG_SCHED_SMT?
78 #define ARCH_HAS_SCHED_WAKE_IDLE
79 /* Common values for SMT siblings */
80 #ifndef SD_SIBLING_INIT
81 #define SD_SIBLING_INIT (struct sched_domain) { \
82 .span = CPU_MASK_NONE, \
88 .imbalance_pct = 110, \
89 .cache_nice_tries = 0, \
96 .flags = SD_LOAD_BALANCE \
97 | SD_BALANCE_NEWIDLE \
101 | SD_SHARE_CPUPOWER, \
102 .last_balance = jiffies, \
103 .balance_interval = 1, \
104 .nr_balance_failed = 0, \
107 #endif /* CONFIG_SCHED_SMT */
109 /* Common values for CPUs */
111 #define SD_CPU_INIT (struct sched_domain) { \
112 .span = CPU_MASK_NONE, \
118 .imbalance_pct = 125, \
119 .cache_nice_tries = 1, \
120 .per_cpu_gain = 100, \
126 .flags = SD_LOAD_BALANCE \
127 | SD_BALANCE_NEWIDLE \
130 .last_balance = jiffies, \
131 .balance_interval = 1, \
132 .nr_balance_failed = 0, \
136 /* sched_domains SD_ALLNODES_INIT for NUMA machines */
137 #define SD_ALLNODES_INIT (struct sched_domain) { \
138 .span = CPU_MASK_NONE, \
141 .min_interval = 64, \
142 .max_interval = 64*num_online_cpus(), \
143 .busy_factor = 128, \
144 .imbalance_pct = 133, \
145 .cache_hot_time = (10*1000000), \
146 .cache_nice_tries = 1, \
149 .newidle_idx = 0, /* unused */ \
150 .wake_idx = 0, /* unused */ \
151 .forkexec_idx = 0, /* unused */ \
152 .per_cpu_gain = 100, \
153 .flags = SD_LOAD_BALANCE, \
154 .last_balance = jiffies, \
155 .balance_interval = 64, \
156 .nr_balance_failed = 0, \
161 #error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!!
163 #endif /* CONFIG_NUMA */
165 #endif /* _LINUX_TOPOLOGY_H */