sched: tune multi-core idle balancing
[linux-2.6-block.git] / include / linux / topology.h
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1da177e4
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1/*
2 * include/linux/topology.h
3 *
4 * Written by: Matthew Dobson, IBM Corporation
5 *
6 * Copyright (C) 2002, IBM Corp.
7 *
32525d02 8 * All rights reserved.
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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 <asm/topology.h>
35
36#ifndef node_has_online_mem
37#define node_has_online_mem(nid) (1)
38#endif
39
40#ifndef nr_cpus_node
41#define nr_cpus_node(node) \
42 ({ \
43 cpumask_t __tmp__; \
44 __tmp__ = node_to_cpumask(node); \
45 cpus_weight(__tmp__); \
46 })
47#endif
48
49#define for_each_node_with_cpus(node) \
50 for_each_online_node(node) \
51 if (nr_cpus_node(node))
52
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53/* Conform to ACPI 2.0 SLIT distance definitions */
54#define LOCAL_DISTANCE 10
55#define REMOTE_DISTANCE 20
f787a503 56#ifndef node_distance
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57#define node_distance(from,to) ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
58#endif
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59#ifndef RECLAIM_DISTANCE
60/*
61 * If the distance between nodes in a system is larger than RECLAIM_DISTANCE
62 * (in whatever arch specific measurement units returned by node_distance())
63 * then switch on zone reclaim on boot.
64 */
65#define RECLAIM_DISTANCE 20
66#endif
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67#ifndef PENALTY_FOR_NODE_WITH_CPUS
68#define PENALTY_FOR_NODE_WITH_CPUS (1)
69#endif
70
71/*
72 * Below are the 3 major initializers used in building sched_domains:
73 * SD_SIBLING_INIT, for SMT domains
74 * SD_CPU_INIT, for SMP domains
75 * SD_NODE_INIT, for NUMA domains
76 *
77 * Any architecture that cares to do any tuning to these values should do so
78 * by defining their own arch-specific initializer in include/asm/topology.h.
79 * A definition there will automagically override these default initializers
80 * and allow arch-specific performance tuning of sched_domains.
81 */
82#ifdef CONFIG_SCHED_SMT
83/* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
84 * so can't we drop this in favor of CONFIG_SCHED_SMT?
85 */
86#define ARCH_HAS_SCHED_WAKE_IDLE
87/* Common values for SMT siblings */
88#ifndef SD_SIBLING_INIT
89#define SD_SIBLING_INIT (struct sched_domain) { \
90 .span = CPU_MASK_NONE, \
91 .parent = NULL, \
1a848870 92 .child = NULL, \
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93 .groups = NULL, \
94 .min_interval = 1, \
95 .max_interval = 2, \
ac7d5504 96 .busy_factor = 64, \
1da177e4 97 .imbalance_pct = 110, \
1da177e4 98 .cache_nice_tries = 0, \
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99 .busy_idx = 0, \
100 .idle_idx = 0, \
7a6c6bce 101 .newidle_idx = 0, \
7897986b 102 .wake_idx = 0, \
147cbb4b 103 .forkexec_idx = 0, \
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104 .flags = SD_LOAD_BALANCE \
105 | SD_BALANCE_NEWIDLE \
52d85343 106 | SD_BALANCE_FORK \
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107 | SD_BALANCE_EXEC \
108 | SD_WAKE_AFFINE \
109 | SD_WAKE_IDLE \
110 | SD_SHARE_CPUPOWER, \
111 .last_balance = jiffies, \
112 .balance_interval = 1, \
113 .nr_balance_failed = 0, \
114}
115#endif
116#endif /* CONFIG_SCHED_SMT */
117
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118#ifdef CONFIG_SCHED_MC
119/* Common values for MC siblings. for now mostly derived from SD_CPU_INIT */
120#ifndef SD_MC_INIT
121#define SD_MC_INIT (struct sched_domain) { \
122 .span = CPU_MASK_NONE, \
123 .parent = NULL, \
124 .child = NULL, \
125 .groups = NULL, \
126 .min_interval = 1, \
127 .max_interval = 4, \
128 .busy_factor = 64, \
129 .imbalance_pct = 125, \
130 .cache_nice_tries = 1, \
89c4710e 131 .busy_idx = 2, \
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132 .idle_idx = 0, \
133 .newidle_idx = 0, \
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134 .wake_idx = 1, \
135 .forkexec_idx = 1, \
136 .flags = SD_LOAD_BALANCE \
137 | SD_BALANCE_NEWIDLE \
52d85343 138 | SD_BALANCE_FORK \
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139 | SD_BALANCE_EXEC \
140 | SD_WAKE_AFFINE \
141 | SD_SHARE_PKG_RESOURCES\
142 | BALANCE_FOR_MC_POWER, \
143 .last_balance = jiffies, \
144 .balance_interval = 1, \
145 .nr_balance_failed = 0, \
146}
147#endif
148#endif /* CONFIG_SCHED_MC */
149
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150/* Common values for CPUs */
151#ifndef SD_CPU_INIT
152#define SD_CPU_INIT (struct sched_domain) { \
153 .span = CPU_MASK_NONE, \
154 .parent = NULL, \
1a848870 155 .child = NULL, \
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156 .groups = NULL, \
157 .min_interval = 1, \
158 .max_interval = 4, \
159 .busy_factor = 64, \
160 .imbalance_pct = 125, \
1da177e4 161 .cache_nice_tries = 1, \
7897986b 162 .busy_idx = 2, \
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163 .idle_idx = 1, \
164 .newidle_idx = 2, \
7897986b 165 .wake_idx = 1, \
687f1661 166 .forkexec_idx = 1, \
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167 .flags = SD_LOAD_BALANCE \
168 | SD_BALANCE_NEWIDLE \
52d85343 169 | SD_BALANCE_FORK \
1da177e4 170 | SD_BALANCE_EXEC \
5c45bf27 171 | SD_WAKE_AFFINE \
89c4710e 172 | BALANCE_FOR_PKG_POWER,\
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173 .last_balance = jiffies, \
174 .balance_interval = 1, \
175 .nr_balance_failed = 0, \
176}
177#endif
178
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179/* sched_domains SD_ALLNODES_INIT for NUMA machines */
180#define SD_ALLNODES_INIT (struct sched_domain) { \
181 .span = CPU_MASK_NONE, \
182 .parent = NULL, \
1a848870 183 .child = NULL, \
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184 .groups = NULL, \
185 .min_interval = 64, \
186 .max_interval = 64*num_online_cpus(), \
187 .busy_factor = 128, \
188 .imbalance_pct = 133, \
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189 .cache_nice_tries = 1, \
190 .busy_idx = 3, \
191 .idle_idx = 3, \
192 .newidle_idx = 0, /* unused */ \
193 .wake_idx = 0, /* unused */ \
194 .forkexec_idx = 0, /* unused */ \
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195 .flags = SD_LOAD_BALANCE \
196 | SD_SERIALIZE, \
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197 .last_balance = jiffies, \
198 .balance_interval = 64, \
199 .nr_balance_failed = 0, \
200}
201
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202#ifdef CONFIG_NUMA
203#ifndef SD_NODE_INIT
204#error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!!
205#endif
206#endif /* CONFIG_NUMA */
207
208#endif /* _LINUX_TOPOLOGY_H */