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(_name) \
35 static SYSDEV_ATTR(_name, 0444, show_##_name, NULL)
37 #define define_id_show_func(name) \
38 static ssize_t show_##name(struct sys_device *dev, \
39 struct sysdev_attribute *attr, char *buf) \
41 unsigned int cpu = dev->id; \
42 return sprintf(buf, "%d\n", topology_##name(cpu)); \
45 #if defined(topology_thread_siblings) || defined(topology_core_siblings)
46 static ssize_t
show_cpumap(int type
, cpumask_t
*mask
, char *buf
)
48 ptrdiff_t len
= PTR_ALIGN(buf
+ PAGE_SIZE
- 1, PAGE_SIZE
) - buf
;
53 cpulist_scnprintf(buf
, len
-2, mask
) :
54 cpumask_scnprintf(buf
, len
-2, mask
);
62 #ifdef arch_provides_topology_pointers
63 #define define_siblings_show_map(name) \
64 static ssize_t show_##name(struct sys_device *dev, \
65 struct sysdev_attribute *attr, char *buf) \
67 unsigned int cpu = dev->id; \
68 return show_cpumap(0, &(topology_##name(cpu)), buf); \
71 #define define_siblings_show_list(name) \
72 static ssize_t show_##name##_list(struct sys_device *dev, \
73 struct sysdev_attribute *attr, \
76 unsigned int cpu = dev->id; \
77 return show_cpumap(1, &(topology_##name(cpu)), buf); \
81 #define define_siblings_show_map(name) \
82 static ssize_t show_##name(struct sys_device *dev, \
83 struct sysdev_attribute *attr, char *buf) \
85 unsigned int cpu = dev->id; \
86 cpumask_t mask = topology_##name(cpu); \
87 return show_cpumap(0, &mask, buf); \
90 #define define_siblings_show_list(name) \
91 static ssize_t show_##name##_list(struct sys_device *dev, \
92 struct sysdev_attribute *attr, \
95 unsigned int cpu = dev->id; \
96 cpumask_t mask = topology_##name(cpu); \
97 return show_cpumap(1, &mask, 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_siblings
);
111 define_one_ro(thread_siblings
);
112 define_one_ro(thread_siblings_list
);
114 define_siblings_show_func(core_siblings
);
115 define_one_ro(core_siblings
);
116 define_one_ro(core_siblings_list
);
118 static struct attribute
*default_attrs
[] = {
119 &attr_physical_package_id
.attr
,
121 &attr_thread_siblings
.attr
,
122 &attr_thread_siblings_list
.attr
,
123 &attr_core_siblings
.attr
,
124 &attr_core_siblings_list
.attr
,
128 static struct attribute_group topology_attr_group
= {
129 .attrs
= default_attrs
,
133 /* Add/Remove cpu_topology interface for CPU device */
134 static int __cpuinit
topology_add_dev(unsigned int cpu
)
136 struct sys_device
*sys_dev
= get_cpu_sysdev(cpu
);
138 return sysfs_create_group(&sys_dev
->kobj
, &topology_attr_group
);
141 static void __cpuinit
topology_remove_dev(unsigned int cpu
)
143 struct sys_device
*sys_dev
= get_cpu_sysdev(cpu
);
145 sysfs_remove_group(&sys_dev
->kobj
, &topology_attr_group
);
148 static int __cpuinit
topology_cpu_callback(struct notifier_block
*nfb
,
149 unsigned long action
, void *hcpu
)
151 unsigned int cpu
= (unsigned long)hcpu
;
156 case CPU_UP_PREPARE_FROZEN
:
157 rc
= topology_add_dev(cpu
);
159 case CPU_UP_CANCELED
:
160 case CPU_UP_CANCELED_FROZEN
:
162 case CPU_DEAD_FROZEN
:
163 topology_remove_dev(cpu
);
166 return rc
? NOTIFY_BAD
: NOTIFY_OK
;
169 static int __cpuinit
topology_sysfs_init(void)
174 for_each_online_cpu(cpu
) {
175 rc
= topology_add_dev(cpu
);
179 hotcpu_notifier(topology_cpu_callback
, 0);
184 device_initcall(topology_sysfs_init
);