drivers: dma-contiguous: refactor dma_alloc_from_contiguous()
[linux-2.6.git] / 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/init.h>
27 #include <linux/mm.h>
28 #include <linux/cpu.h>
29 #include <linux/module.h>
30 #include <linux/hardirq.h>
31 #include <linux/topology.h>
32
33 #define define_one_ro_named(_name, _func)                               \
34         static DEVICE_ATTR(_name, 0444, _func, NULL)
35
36 #define define_one_ro(_name)                            \
37         static DEVICE_ATTR(_name, 0444, show_##_name, NULL)
38
39 #define define_id_show_func(name)                               \
40 static ssize_t show_##name(struct device *dev,                  \
41                 struct device_attribute *attr, char *buf)       \
42 {                                                               \
43         unsigned int cpu = dev->id;                             \
44         return sprintf(buf, "%d\n", topology_##name(cpu));      \
45 }
46
47 #if defined(topology_thread_cpumask) || defined(topology_core_cpumask) || \
48     defined(topology_book_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 device *dev,                          \
68                            struct device_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 device *dev,                   \
76                                   struct device_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 device *dev,                          \
86                            struct device_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 device *dev,                   \
93                                   struct device_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 #ifdef CONFIG_SCHED_BOOK
118 define_id_show_func(book_id);
119 define_one_ro(book_id);
120 define_siblings_show_func(book_cpumask);
121 define_one_ro_named(book_siblings, show_book_cpumask);
122 define_one_ro_named(book_siblings_list, show_book_cpumask_list);
123 #endif
124
125 static struct attribute *default_attrs[] = {
126         &dev_attr_physical_package_id.attr,
127         &dev_attr_core_id.attr,
128         &dev_attr_thread_siblings.attr,
129         &dev_attr_thread_siblings_list.attr,
130         &dev_attr_core_siblings.attr,
131         &dev_attr_core_siblings_list.attr,
132 #ifdef CONFIG_SCHED_BOOK
133         &dev_attr_book_id.attr,
134         &dev_attr_book_siblings.attr,
135         &dev_attr_book_siblings_list.attr,
136 #endif
137         NULL
138 };
139
140 static struct attribute_group topology_attr_group = {
141         .attrs = default_attrs,
142         .name = "topology"
143 };
144
145 /* Add/Remove cpu_topology interface for CPU device */
146 static int __cpuinit topology_add_dev(unsigned int cpu)
147 {
148         struct device *dev = get_cpu_device(cpu);
149
150         return sysfs_create_group(&dev->kobj, &topology_attr_group);
151 }
152
153 static void __cpuinit topology_remove_dev(unsigned int cpu)
154 {
155         struct device *dev = get_cpu_device(cpu);
156
157         sysfs_remove_group(&dev->kobj, &topology_attr_group);
158 }
159
160 static int __cpuinit topology_cpu_callback(struct notifier_block *nfb,
161                                            unsigned long action, void *hcpu)
162 {
163         unsigned int cpu = (unsigned long)hcpu;
164         int rc = 0;
165
166         switch (action) {
167         case CPU_UP_PREPARE:
168         case CPU_UP_PREPARE_FROZEN:
169                 rc = topology_add_dev(cpu);
170                 break;
171         case CPU_UP_CANCELED:
172         case CPU_UP_CANCELED_FROZEN:
173         case CPU_DEAD:
174         case CPU_DEAD_FROZEN:
175                 topology_remove_dev(cpu);
176                 break;
177         }
178         return notifier_from_errno(rc);
179 }
180
181 static int __cpuinit topology_sysfs_init(void)
182 {
183         int cpu;
184         int rc;
185
186         for_each_online_cpu(cpu) {
187                 rc = topology_add_dev(cpu);
188                 if (rc)
189                         return rc;
190         }
191         hotcpu_notifier(topology_cpu_callback, 0);
192
193         return 0;
194 }
195
196 device_initcall(topology_sysfs_init);