2 * driver/base/topology.c - Populate sysfs with cpu topology information
4 * Written by: Zhang Yanmin, Intel Corporation
6 * Copyright (C) 2006, Intel 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.
26 #include <linux/sysdev.h>
27 #include <linux/init.h>
29 #include <linux/cpu.h>
30 #include <linux/module.h>
31 #include <linux/hardirq.h>
32 #include <linux/topology.h>
34 #define define_one_ro_named(_name, _func) \
35 static SYSDEV_ATTR(_name, 0444, _func, NULL)
37 #define define_one_ro(_name) \
38 static SYSDEV_ATTR(_name, 0444, show_##_name, NULL)
40 #define define_id_show_func(name) \
41 static ssize_t show_##name(struct sys_device *dev, \
42 struct sysdev_attribute *attr, char *buf) \
44 unsigned int cpu = dev->id; \
45 return sprintf(buf, "%d\n", topology_##name(cpu)); \
48 #if defined(topology_thread_cpumask) || defined(topology_core_cpumask) || \
49 defined(topology_book_cpumask)
50 static ssize_t show_cpumap(int type, const struct cpumask *mask, char *buf)
52 ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf;
57 cpulist_scnprintf(buf, len-2, mask) :
58 cpumask_scnprintf(buf, len-2, mask);
66 #ifdef arch_provides_topology_pointers
67 #define define_siblings_show_map(name) \
68 static ssize_t show_##name(struct sys_device *dev, \
69 struct sysdev_attribute *attr, char *buf) \
71 unsigned int cpu = dev->id; \
72 return show_cpumap(0, topology_##name(cpu), buf); \
75 #define define_siblings_show_list(name) \
76 static ssize_t show_##name##_list(struct sys_device *dev, \
77 struct sysdev_attribute *attr, \
80 unsigned int cpu = dev->id; \
81 return show_cpumap(1, topology_##name(cpu), buf); \
85 #define define_siblings_show_map(name) \
86 static ssize_t show_##name(struct sys_device *dev, \
87 struct sysdev_attribute *attr, char *buf) \
89 return show_cpumap(0, topology_##name(dev->id), buf); \
92 #define define_siblings_show_list(name) \
93 static ssize_t show_##name##_list(struct sys_device *dev, \
94 struct sysdev_attribute *attr, \
97 return show_cpumap(1, topology_##name(dev->id), buf); \
101 #define define_siblings_show_func(name) \
102 define_siblings_show_map(name); define_siblings_show_list(name)
104 define_id_show_func(physical_package_id);
105 define_one_ro(physical_package_id);
107 define_id_show_func(core_id);
108 define_one_ro(core_id);
110 define_siblings_show_func(thread_cpumask);
111 define_one_ro_named(thread_siblings, show_thread_cpumask);
112 define_one_ro_named(thread_siblings_list, show_thread_cpumask_list);
114 define_siblings_show_func(core_cpumask);
115 define_one_ro_named(core_siblings, show_core_cpumask);
116 define_one_ro_named(core_siblings_list, show_core_cpumask_list);
118 #ifdef CONFIG_SCHED_BOOK
119 define_id_show_func(book_id);
120 define_one_ro(book_id);
121 define_siblings_show_func(book_cpumask);
122 define_one_ro_named(book_siblings, show_book_cpumask);
123 define_one_ro_named(book_siblings_list, show_book_cpumask_list);
126 static struct attribute *default_attrs[] = {
127 &attr_physical_package_id.attr,
129 &attr_thread_siblings.attr,
130 &attr_thread_siblings_list.attr,
131 &attr_core_siblings.attr,
132 &attr_core_siblings_list.attr,
133 #ifdef CONFIG_SCHED_BOOK
135 &attr_book_siblings.attr,
136 &attr_book_siblings_list.attr,
141 static struct attribute_group topology_attr_group = {
142 .attrs = default_attrs,
146 /* Add/Remove cpu_topology interface for CPU device */
147 static int __cpuinit topology_add_dev(unsigned int cpu)
149 struct sys_device *sys_dev = get_cpu_sysdev(cpu);
151 return sysfs_create_group(&sys_dev->kobj, &topology_attr_group);
154 static void __cpuinit topology_remove_dev(unsigned int cpu)
156 struct sys_device *sys_dev = get_cpu_sysdev(cpu);
158 sysfs_remove_group(&sys_dev->kobj, &topology_attr_group);
161 static int __cpuinit topology_cpu_callback(struct notifier_block *nfb,
162 unsigned long action, void *hcpu)
164 unsigned int cpu = (unsigned long)hcpu;
169 case CPU_UP_PREPARE_FROZEN:
170 rc = topology_add_dev(cpu);
172 case CPU_UP_CANCELED:
173 case CPU_UP_CANCELED_FROZEN:
175 case CPU_DEAD_FROZEN:
176 topology_remove_dev(cpu);
179 return notifier_from_errno(rc);
182 static int __cpuinit topology_sysfs_init(void)
187 for_each_online_cpu(cpu) {
188 rc = topology_add_dev(cpu);
192 hotcpu_notifier(topology_cpu_callback, 0);
197 device_initcall(topology_sysfs_init);