aboutsummaryrefslogtreecommitdiff
path: root/drivers/base/topology.c
blob: f6f37a05a0c3a5664503040bcdfaae32516d6e6c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
/*
 * driver/base/topology.c - Populate sysfs with cpu topology information
 *
 * Written by: Zhang Yanmin, Intel Corporation
 *
 * Copyright (C) 2006, Intel Corp.
 *
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */
#include <linux/sysdev.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/cpu.h>
#include <linux/module.h>
#include <linux/hardirq.h>
#include <linux/topology.h>

#define define_one_ro_named(_name, _func)				\
static SYSDEV_ATTR(_name, 0444, _func, NULL)

#define define_one_ro(_name)				\
static SYSDEV_ATTR(_name, 0444, show_##_name, NULL)

#define define_id_show_func(name)				\
static ssize_t show_##name(struct sys_device *dev,		\
		struct sysdev_attribute *attr, char *buf)	\
{								\
	unsigned int cpu = dev->id;				\
	return sprintf(buf, "%d\n", topology_##name(cpu));	\
}

#if defined(topology_thread_cpumask) || defined(topology_core_cpumask) || \
    defined(topology_book_cpumask)
static ssize_t show_cpumap(int type, const struct cpumask *mask, char *buf)
{
	ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf;
	int n = 0;

	if (len > 1) {
		n = type?
			cpulist_scnprintf(buf, len-2, mask) :
			cpumask_scnprintf(buf, len-2, mask);
		buf[n++] = '\n';
		buf[n] = '\0';
	}
	return n;
}
#endif

#ifdef arch_provides_topology_pointers
#define define_siblings_show_map(name)					\
static ssize_t show_##name(struct sys_device *dev,			\
			   struct sysdev_attribute *attr, char *buf)	\
{									\
	unsigned int cpu = dev->id;					\
	return show_cpumap(0, topology_##name(cpu), buf);		\
}

#define define_siblings_show_list(name)					\
static ssize_t show_##name##_list(struct sys_device *dev,		\
				  struct sysdev_attribute *attr,	\
				  char *buf)				\
{									\
	unsigned int cpu = dev->id;					\
	return show_cpumap(1, topology_##name(cpu), buf);		\
}

#else
#define define_siblings_show_map(name)					\
static ssize_t show_##name(struct sys_device *dev,			\
			   struct sysdev_attribute *attr, char *buf)	\
{									\
	return show_cpumap(0, topology_##name(dev->id), buf);		\
}

#define define_siblings_show_list(name)					\
static ssize_t show_##name##_list(struct sys_device *dev,		\
				  struct sysdev_attribute *attr,	\
				  char *buf)				\
{									\
	return show_cpumap(1, topology_##name(dev->id), buf);		\
}
#endif

#define define_siblings_show_func(name)		\
	define_siblings_show_map(name); define_siblings_show_list(name)

define_id_show_func(physical_package_id);
define_one_ro(physical_package_id);

define_id_show_func(core_id);
define_one_ro(core_id);

define_siblings_show_func(thread_cpumask);
define_one_ro_named(thread_siblings, show_thread_cpumask);
define_one_ro_named(thread_siblings_list, show_thread_cpumask_list);

define_siblings_show_func(core_cpumask);
define_one_ro_named(core_siblings, show_core_cpumask);
define_one_ro_named(core_siblings_list, show_core_cpumask_list);

#ifdef CONFIG_SCHED_BOOK
define_id_show_func(book_id);
define_one_ro(book_id);
define_siblings_show_func(book_cpumask);
define_one_ro_named(book_siblings, show_book_cpumask);
define_one_ro_named(book_siblings_list, show_book_cpumask_list);
#endif

static struct attribute *default_attrs[] = {
	&attr_physical_package_id.attr,
	&attr_core_id.attr,
	&attr_thread_siblings.attr,
	&attr_thread_siblings_list.attr,
	&attr_core_siblings.attr,
	&attr_core_siblings_list.attr,
#ifdef CONFIG_SCHED_BOOK
	&attr_book_id.attr,
	&attr_book_siblings.attr,
	&attr_book_siblings_list.attr,
#endif
	NULL
};

static struct attribute_group topology_attr_group = {
	.attrs = default_attrs,
	.name = "topology"
};

/* Add/Remove cpu_topology interface for CPU device */
static int __cpuinit topology_add_dev(unsigned int cpu)
{
	struct sys_device *sys_dev = get_cpu_sysdev(cpu);

	return sysfs_create_group(&sys_dev->kobj, &topology_attr_group);
}

static void __cpuinit topology_remove_dev(unsigned int cpu)
{
	struct sys_device *sys_dev = get_cpu_sysdev(cpu);

	sysfs_remove_group(&sys_dev->kobj, &topology_attr_group);
}

static int __cpuinit topology_cpu_callback(struct notifier_block *nfb,
					   unsigned long action, void *hcpu)
{
	unsigned int cpu = (unsigned long)hcpu;
	int rc = 0;

	switch (action) {
	case CPU_UP_PREPARE:
	case CPU_UP_PREPARE_FROZEN:
		rc = topology_add_dev(cpu);
		break;
	case CPU_UP_CANCELED:
	case CPU_UP_CANCELED_FROZEN:
	case CPU_DEAD:
	case CPU_DEAD_FROZEN:
		topology_remove_dev(cpu);
		break;
	}
	return notifier_from_errno(rc);
}

static int __cpuinit topology_sysfs_init(void)
{
	int cpu;
	int rc;

	for_each_online_cpu(cpu) {
		rc = topology_add_dev(cpu);
		if (rc)
			return rc;
	}
	hotcpu_notifier(topology_cpu_callback, 0);

	return 0;
}

device_initcall(topology_sysfs_init);