Merge branch 'master' of ssh://master.kernel.org/home/ftp/pub/scm/linux/kernel/git...
[linux-2.6] / drivers / base / topology.c
1 /*
2  * driver/base/topology.c - Populate sysfs with cpu topology information
3  *
4  * Written by: Zhang Yanmin, Intel Corporation
5  *
6  * Copyright (C) 2006, Intel Corp.
7  *
8  * All rights reserved.
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  */
26 #include <linux/sysdev.h>
27 #include <linux/init.h>
28 #include <linux/mm.h>
29 #include <linux/cpu.h>
30 #include <linux/module.h>
31 #include <linux/hardirq.h>
32 #include <linux/topology.h>
33
34 #define define_one_ro_named(_name, _func)                               \
35 static SYSDEV_ATTR(_name, 0444, _func, NULL)
36
37 #define define_one_ro(_name)                            \
38 static SYSDEV_ATTR(_name, 0444, show_##_name, NULL)
39
40 #define define_id_show_func(name)                               \
41 static ssize_t show_##name(struct sys_device *dev,              \
42                 struct sysdev_attribute *attr, char *buf)       \
43 {                                                               \
44         unsigned int cpu = dev->id;                             \
45         return sprintf(buf, "%d\n", topology_##name(cpu));      \
46 }
47
48 #if defined(topology_thread_cpumask) || defined(topology_core_cpumask)
49 static ssize_t show_cpumap(int type, const struct cpumask *mask, char *buf)
50 {
51         ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf;
52         int n = 0;
53
54         if (len > 1) {
55                 n = type?
56                         cpulist_scnprintf(buf, len-2, mask) :
57                         cpumask_scnprintf(buf, len-2, mask);
58                 buf[n++] = '\n';
59                 buf[n] = '\0';
60         }
61         return n;
62 }
63 #endif
64
65 #ifdef arch_provides_topology_pointers
66 #define define_siblings_show_map(name)                                  \
67 static ssize_t show_##name(struct sys_device *dev,                      \
68                            struct sysdev_attribute *attr, char *buf)    \
69 {                                                                       \
70         unsigned int cpu = dev->id;                                     \
71         return show_cpumap(0, topology_##name(cpu), buf);               \
72 }
73
74 #define define_siblings_show_list(name)                                 \
75 static ssize_t show_##name##_list(struct sys_device *dev,               \
76                                   struct sysdev_attribute *attr,        \
77                                   char *buf)                            \
78 {                                                                       \
79         unsigned int cpu = dev->id;                                     \
80         return show_cpumap(1, topology_##name(cpu), buf);               \
81 }
82
83 #else
84 #define define_siblings_show_map(name)                                  \
85 static ssize_t show_##name(struct sys_device *dev,                      \
86                            struct sysdev_attribute *attr, char *buf)    \
87 {                                                                       \
88         return show_cpumap(0, topology_##name(dev->id), buf);           \
89 }
90
91 #define define_siblings_show_list(name)                                 \
92 static ssize_t show_##name##_list(struct sys_device *dev,               \
93                                   struct sysdev_attribute *attr,        \
94                                   char *buf)                            \
95 {                                                                       \
96         return show_cpumap(1, topology_##name(dev->id), buf);           \
97 }
98 #endif
99
100 #define define_siblings_show_func(name)         \
101         define_siblings_show_map(name); define_siblings_show_list(name)
102
103 define_id_show_func(physical_package_id);
104 define_one_ro(physical_package_id);
105
106 define_id_show_func(core_id);
107 define_one_ro(core_id);
108
109 define_siblings_show_func(thread_cpumask);
110 define_one_ro_named(thread_siblings, show_thread_cpumask);
111 define_one_ro_named(thread_siblings_list, show_thread_cpumask_list);
112
113 define_siblings_show_func(core_cpumask);
114 define_one_ro_named(core_siblings, show_core_cpumask);
115 define_one_ro_named(core_siblings_list, show_core_cpumask_list);
116
117 static struct attribute *default_attrs[] = {
118         &attr_physical_package_id.attr,
119         &attr_core_id.attr,
120         &attr_thread_siblings.attr,
121         &attr_thread_siblings_list.attr,
122         &attr_core_siblings.attr,
123         &attr_core_siblings_list.attr,
124         NULL
125 };
126
127 static struct attribute_group topology_attr_group = {
128         .attrs = default_attrs,
129         .name = "topology"
130 };
131
132 /* Add/Remove cpu_topology interface for CPU device */
133 static int __cpuinit topology_add_dev(unsigned int cpu)
134 {
135         struct sys_device *sys_dev = get_cpu_sysdev(cpu);
136
137         return sysfs_create_group(&sys_dev->kobj, &topology_attr_group);
138 }
139
140 static void __cpuinit topology_remove_dev(unsigned int cpu)
141 {
142         struct sys_device *sys_dev = get_cpu_sysdev(cpu);
143
144         sysfs_remove_group(&sys_dev->kobj, &topology_attr_group);
145 }
146
147 static int __cpuinit topology_cpu_callback(struct notifier_block *nfb,
148                                            unsigned long action, void *hcpu)
149 {
150         unsigned int cpu = (unsigned long)hcpu;
151         int rc = 0;
152
153         switch (action) {
154         case CPU_UP_PREPARE:
155         case CPU_UP_PREPARE_FROZEN:
156                 rc = topology_add_dev(cpu);
157                 break;
158         case CPU_UP_CANCELED:
159         case CPU_UP_CANCELED_FROZEN:
160         case CPU_DEAD:
161         case CPU_DEAD_FROZEN:
162                 topology_remove_dev(cpu);
163                 break;
164         }
165         return rc ? NOTIFY_BAD : NOTIFY_OK;
166 }
167
168 static int __cpuinit topology_sysfs_init(void)
169 {
170         int cpu;
171         int rc;
172
173         for_each_online_cpu(cpu) {
174                 rc = topology_add_dev(cpu);
175                 if (rc)
176                         return rc;
177         }
178         hotcpu_notifier(topology_cpu_callback, 0);
179
180         return 0;
181 }
182
183 device_initcall(topology_sysfs_init);