aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/base/topology.c
blob: 915810f6237eeca929235e1502983080989a3376 (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
/*
 * 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/topology.h>

#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, char *buf)	\
{								\
	unsigned int cpu = dev->id;				\
	return sprintf(buf, "%d\n", topology_##name(cpu));	\
}

#define define_siblings_show_func(name)					\
static ssize_t show_##name(struct sys_device *dev, char *buf)		\
{									\
	ssize_t len = -1;						\
	unsigned int cpu = dev->id;					\
	len = cpumask_scnprintf(buf, NR_CPUS+1, topology_##name(cpu));	\
	return (len + sprintf(buf + len, "\n"));			\
}

#ifdef	topology_physical_package_id
define_id_show_func(physical_package_id);
define_one_ro(physical_package_id);
#define ref_physical_package_id_attr	&attr_physical_package_id.attr,
#else
#define ref_physical_package_id_attr
#endif

#ifdef topology_core_id
define_id_show_func(core_id);
define_one_ro(core_id);
#define ref_core_id_attr		&attr_core_id.attr,
#else
#define ref_core_id_attr
#endif

#ifdef topology_thread_siblings
define_siblings_show_func(thread_siblings);
define_one_ro(thread_siblings);
#define ref_thread_siblings_attr	&attr_thread_siblings.attr,
#else
#define ref_thread_siblings_attr
#endif

#ifdef topology_core_siblings
define_siblings_show_func(core_siblings);
define_one_ro(core_siblings);
#define ref_core_siblings_attr		&attr_core_siblings.attr,
#else
#define ref_core_siblings_attr
#endif

static struct attribute *default_attrs[] = {
	ref_physical_package_id_attr
	ref_core_id_attr
	ref_thread_siblings_attr
	ref_core_siblings_attr
	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(struct sys_device * sys_dev)
{
	sysfs_create_group(&sys_dev->kobj, &topology_attr_group);
	return 0;
}

static int __cpuinit topology_remove_dev(struct sys_device * sys_dev)
{
	sysfs_remove_group(&sys_dev->kobj, &topology_attr_group);
	return 0;
}

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

	sys_dev = get_cpu_sysdev(cpu);
	switch (action) {
	case CPU_ONLINE:
		topology_add_dev(sys_dev);
		break;
	case CPU_DEAD:
		topology_remove_dev(sys_dev);
		break;
	}
	return NOTIFY_OK;
}

static struct notifier_block topology_cpu_notifier =
{
	.notifier_call = topology_cpu_callback,
};

static int __cpuinit topology_sysfs_init(void)
{
	int i;

	for_each_online_cpu(i) {
		topology_cpu_callback(&topology_cpu_notifier, CPU_ONLINE,
				(void *)(long)i);
	}

	register_cpu_notifier(&topology_cpu_notifier);

	return 0;
}

device_initcall(topology_sysfs_init);

Privacy Policy