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 static ssize_t
show_cpumap(int type
, const struct cpumask
*mask
, char *buf
)
51 ptrdiff_t len
= PTR_ALIGN(buf
+ PAGE_SIZE
- 1, PAGE_SIZE
) - buf
;
56 cpulist_scnprintf(buf
, len
-2, mask
) :
57 cpumask_scnprintf(buf
, len
-2, mask
);
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) \
70 unsigned int cpu = dev->id; \
71 return show_cpumap(0, topology_##name(cpu), buf); \
74 #define define_siblings_show_list(name) \
75 static ssize_t show_##name##_list(struct sys_device *dev, \
76 struct sysdev_attribute *attr, \
79 unsigned int cpu = dev->id; \
80 return show_cpumap(1, topology_##name(cpu), buf); \
84 #define define_siblings_show_map(name) \
85 static ssize_t show_##name(struct sys_device *dev, \
86 struct sysdev_attribute *attr, char *buf) \
88 return show_cpumap(0, topology_##name(dev->id), buf); \
91 #define define_siblings_show_list(name) \
92 static ssize_t show_##name##_list(struct sys_device *dev, \
93 struct sysdev_attribute *attr, \
96 return show_cpumap(1, topology_##name(dev->id), buf); \
100 #define define_siblings_show_func(name) \
101 define_siblings_show_map(name); define_siblings_show_list(name)
103 define_id_show_func(physical_package_id
);
104 define_one_ro(physical_package_id
);
106 define_id_show_func(core_id
);
107 define_one_ro(core_id
);
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
);
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
);
117 static struct attribute
*default_attrs
[] = {
118 &attr_physical_package_id
.attr
,
120 &attr_thread_siblings
.attr
,
121 &attr_thread_siblings_list
.attr
,
122 &attr_core_siblings
.attr
,
123 &attr_core_siblings_list
.attr
,
127 static struct attribute_group topology_attr_group
= {
128 .attrs
= default_attrs
,
132 /* Add/Remove cpu_topology interface for CPU device */
133 static int __cpuinit
topology_add_dev(unsigned int cpu
)
135 struct sys_device
*sys_dev
= get_cpu_sysdev(cpu
);
137 return sysfs_create_group(&sys_dev
->kobj
, &topology_attr_group
);
140 static void __cpuinit
topology_remove_dev(unsigned int cpu
)
142 struct sys_device
*sys_dev
= get_cpu_sysdev(cpu
);
144 sysfs_remove_group(&sys_dev
->kobj
, &topology_attr_group
);
147 static int __cpuinit
topology_cpu_callback(struct notifier_block
*nfb
,
148 unsigned long action
, void *hcpu
)
150 unsigned int cpu
= (unsigned long)hcpu
;
155 case CPU_UP_PREPARE_FROZEN
:
156 rc
= topology_add_dev(cpu
);
158 case CPU_UP_CANCELED
:
159 case CPU_UP_CANCELED_FROZEN
:
161 case CPU_DEAD_FROZEN
:
162 topology_remove_dev(cpu
);
165 return rc
? NOTIFY_BAD
: NOTIFY_OK
;
168 static int __cpuinit
topology_sysfs_init(void)
173 for_each_online_cpu(cpu
) {
174 rc
= topology_add_dev(cpu
);
178 hotcpu_notifier(topology_cpu_callback
, 0);
183 device_initcall(topology_sysfs_init
);