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 static inline int __next_node_with_cpus(int node)
50 while (node < numnodes && !nr_cpus_node(node));
54 #define for_each_node_with_cpus(node) \
55 for (node = 0; node < numnodes; node = __next_node_with_cpus(node))
58 #define node_distance(from,to) ((from) != (to))
60 #ifndef PENALTY_FOR_NODE_WITH_CPUS
61 #define PENALTY_FOR_NODE_WITH_CPUS (1)
65 * Below are the 3 major initializers used in building sched_domains:
66 * SD_SIBLING_INIT, for SMT domains
67 * SD_CPU_INIT, for SMP domains
68 * SD_NODE_INIT, for NUMA domains
70 * Any architecture that cares to do any tuning to these values should do so
71 * by defining their own arch-specific initializer in include/asm/topology.h.
72 * A definition there will automagically override these default initializers
73 * and allow arch-specific performance tuning of sched_domains.
75 #ifdef CONFIG_SCHED_SMT
76 /* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
77 * so can't we drop this in favor of CONFIG_SCHED_SMT?
79 #define ARCH_HAS_SCHED_WAKE_IDLE
80 /* Common values for SMT siblings */
81 #ifndef SD_SIBLING_INIT
82 #define SD_SIBLING_INIT (struct sched_domain) { \
83 .span = CPU_MASK_NONE, \
89 .imbalance_pct = 110, \
90 .cache_hot_time = 0, \
91 .cache_nice_tries = 0, \
93 .flags = SD_LOAD_BALANCE \
94 | SD_BALANCE_NEWIDLE \
98 | SD_SHARE_CPUPOWER, \
99 .last_balance = jiffies, \
100 .balance_interval = 1, \
101 .nr_balance_failed = 0, \
104 #endif /* CONFIG_SCHED_SMT */
106 /* Common values for CPUs */
108 #define SD_CPU_INIT (struct sched_domain) { \
109 .span = CPU_MASK_NONE, \
115 .imbalance_pct = 125, \
116 .cache_hot_time = (5*1000/2), \
117 .cache_nice_tries = 1, \
118 .per_cpu_gain = 100, \
119 .flags = SD_LOAD_BALANCE \
120 | SD_BALANCE_NEWIDLE \
124 .last_balance = jiffies, \
125 .balance_interval = 1, \
126 .nr_balance_failed = 0, \
132 #error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!!
134 #endif /* CONFIG_NUMA */
136 #endif /* _LINUX_TOPOLOGY_H */