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>
35 #include <asm/topology.h>
38 #define nr_cpus_node(node) \
41 __tmp__ = node_to_cpumask(node); \
42 cpus_weight(__tmp__); \
46 #define for_each_node_with_cpus(node) \
47 for_each_online_node(node) \
48 if (nr_cpus_node(node))
51 /* Conform to ACPI 2.0 SLIT distance definitions */
52 #define LOCAL_DISTANCE 10
53 #define REMOTE_DISTANCE 20
54 #define node_distance(from,to) ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE)
56 #ifndef PENALTY_FOR_NODE_WITH_CPUS
57 #define PENALTY_FOR_NODE_WITH_CPUS (1)
61 * Below are the 3 major initializers used in building sched_domains:
62 * SD_SIBLING_INIT, for SMT domains
63 * SD_CPU_INIT, for SMP domains
64 * SD_NODE_INIT, for NUMA domains
66 * Any architecture that cares to do any tuning to these values should do so
67 * by defining their own arch-specific initializer in include/asm/topology.h.
68 * A definition there will automagically override these default initializers
69 * and allow arch-specific performance tuning of sched_domains.
71 #ifdef CONFIG_SCHED_SMT
72 /* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
73 * so can't we drop this in favor of CONFIG_SCHED_SMT?
75 #define ARCH_HAS_SCHED_WAKE_IDLE
76 /* Common values for SMT siblings */
77 #ifndef SD_SIBLING_INIT
78 #define SD_SIBLING_INIT (struct sched_domain) { \
79 .span = CPU_MASK_NONE, \
85 .imbalance_pct = 110, \
86 .cache_hot_time = 0, \
87 .cache_nice_tries = 0, \
89 .flags = SD_LOAD_BALANCE \
90 | SD_BALANCE_NEWIDLE \
94 | SD_SHARE_CPUPOWER, \
95 .last_balance = jiffies, \
96 .balance_interval = 1, \
97 .nr_balance_failed = 0, \
100 #endif /* CONFIG_SCHED_SMT */
102 /* Common values for CPUs */
104 #define SD_CPU_INIT (struct sched_domain) { \
105 .span = CPU_MASK_NONE, \
111 .imbalance_pct = 125, \
112 .cache_hot_time = (5*1000000/2), \
113 .cache_nice_tries = 1, \
114 .per_cpu_gain = 100, \
115 .flags = SD_LOAD_BALANCE \
116 | SD_BALANCE_NEWIDLE \
121 .last_balance = jiffies, \
122 .balance_interval = 1, \
123 .nr_balance_failed = 0, \
129 #error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!!
131 #endif /* CONFIG_NUMA */
133 #endif /* _LINUX_TOPOLOGY_H */