xref: /linux/drivers/base/topology.c (revision a634dda26186cf9a51567020fcce52bcba5e1e59)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * driver/base/topology.c - Populate sysfs with cpu topology information
4  *
5  * Written by: Zhang Yanmin, Intel Corporation
6  *
7  * Copyright (C) 2006, Intel Corp.
8  *
9  * All rights reserved.
10  */
11 #include <linux/mm.h>
12 #include <linux/cpu.h>
13 #include <linux/module.h>
14 #include <linux/hardirq.h>
15 #include <linux/topology.h>
16 
17 #define define_id_show_func(name, fmt)					\
18 static ssize_t name##_show(struct device *dev,				\
19 			   struct device_attribute *attr, char *buf)	\
20 {									\
21 	return sysfs_emit(buf, fmt "\n", topology_##name(dev->id));	\
22 }
23 
24 #define define_siblings_read_func(name, mask)					\
25 static ssize_t name##_read(struct file *file, struct kobject *kobj,		\
26 			   const struct bin_attribute *attr, char *buf,		\
27 			   loff_t off, size_t count)				\
28 {										\
29 	struct device *dev = kobj_to_dev(kobj);                                 \
30 	cpumask_var_t mask;							\
31 	ssize_t n;								\
32 										\
33 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))				\
34 		return -ENOMEM;							\
35 										\
36 	cpumask_copy(mask, topology_##mask(dev->id));				\
37 	n = cpumap_print_bitmask_to_buf(buf, mask, off, count);			\
38 	free_cpumask_var(mask);							\
39 										\
40 	return n;								\
41 }										\
42 										\
43 static ssize_t name##_list_read(struct file *file, struct kobject *kobj,	\
44 				const struct bin_attribute *attr, char *buf,	\
45 				loff_t off, size_t count)			\
46 {										\
47 	struct device *dev = kobj_to_dev(kobj);					\
48 	cpumask_var_t mask;							\
49 	ssize_t n;								\
50 										\
51 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))				\
52 		return -ENOMEM;							\
53 										\
54 	cpumask_copy(mask, topology_##mask(dev->id));				\
55 	n = cpumap_print_list_to_buf(buf, mask, off, count);			\
56 	free_cpumask_var(mask);							\
57 										\
58 	return n;								\
59 }
60 
61 define_id_show_func(physical_package_id, "%d");
62 static DEVICE_ATTR_RO(physical_package_id);
63 
64 #ifdef TOPOLOGY_DIE_SYSFS
65 define_id_show_func(die_id, "%d");
66 static DEVICE_ATTR_RO(die_id);
67 #endif
68 
69 #ifdef TOPOLOGY_CLUSTER_SYSFS
70 define_id_show_func(cluster_id, "%d");
71 static DEVICE_ATTR_RO(cluster_id);
72 #endif
73 
74 define_id_show_func(core_id, "%d");
75 static DEVICE_ATTR_RO(core_id);
76 
77 define_id_show_func(ppin, "0x%llx");
78 static DEVICE_ATTR_ADMIN_RO(ppin);
79 
80 define_siblings_read_func(thread_siblings, sibling_cpumask);
81 static const BIN_ATTR_RO(thread_siblings, CPUMAP_FILE_MAX_BYTES);
82 static const BIN_ATTR_RO(thread_siblings_list, CPULIST_FILE_MAX_BYTES);
83 
84 define_siblings_read_func(core_cpus, sibling_cpumask);
85 static const BIN_ATTR_RO(core_cpus, CPUMAP_FILE_MAX_BYTES);
86 static const BIN_ATTR_RO(core_cpus_list, CPULIST_FILE_MAX_BYTES);
87 
88 define_siblings_read_func(core_siblings, core_cpumask);
89 static const BIN_ATTR_RO(core_siblings, CPUMAP_FILE_MAX_BYTES);
90 static const BIN_ATTR_RO(core_siblings_list, CPULIST_FILE_MAX_BYTES);
91 
92 #ifdef TOPOLOGY_CLUSTER_SYSFS
93 define_siblings_read_func(cluster_cpus, cluster_cpumask);
94 static const BIN_ATTR_RO(cluster_cpus, CPUMAP_FILE_MAX_BYTES);
95 static const BIN_ATTR_RO(cluster_cpus_list, CPULIST_FILE_MAX_BYTES);
96 #endif
97 
98 #ifdef TOPOLOGY_DIE_SYSFS
99 define_siblings_read_func(die_cpus, die_cpumask);
100 static const BIN_ATTR_RO(die_cpus, CPUMAP_FILE_MAX_BYTES);
101 static const BIN_ATTR_RO(die_cpus_list, CPULIST_FILE_MAX_BYTES);
102 #endif
103 
104 define_siblings_read_func(package_cpus, core_cpumask);
105 static const BIN_ATTR_RO(package_cpus, CPUMAP_FILE_MAX_BYTES);
106 static const BIN_ATTR_RO(package_cpus_list, CPULIST_FILE_MAX_BYTES);
107 
108 #ifdef TOPOLOGY_BOOK_SYSFS
109 define_id_show_func(book_id, "%d");
110 static DEVICE_ATTR_RO(book_id);
111 define_siblings_read_func(book_siblings, book_cpumask);
112 static const BIN_ATTR_RO(book_siblings, CPUMAP_FILE_MAX_BYTES);
113 static const BIN_ATTR_RO(book_siblings_list, CPULIST_FILE_MAX_BYTES);
114 #endif
115 
116 #ifdef TOPOLOGY_DRAWER_SYSFS
117 define_id_show_func(drawer_id, "%d");
118 static DEVICE_ATTR_RO(drawer_id);
119 define_siblings_read_func(drawer_siblings, drawer_cpumask);
120 static const BIN_ATTR_RO(drawer_siblings, CPUMAP_FILE_MAX_BYTES);
121 static const BIN_ATTR_RO(drawer_siblings_list, CPULIST_FILE_MAX_BYTES);
122 #endif
123 
124 static const struct bin_attribute *const bin_attrs[] = {
125 	&bin_attr_core_cpus,
126 	&bin_attr_core_cpus_list,
127 	&bin_attr_thread_siblings,
128 	&bin_attr_thread_siblings_list,
129 	&bin_attr_core_siblings,
130 	&bin_attr_core_siblings_list,
131 #ifdef TOPOLOGY_CLUSTER_SYSFS
132 	&bin_attr_cluster_cpus,
133 	&bin_attr_cluster_cpus_list,
134 #endif
135 #ifdef TOPOLOGY_DIE_SYSFS
136 	&bin_attr_die_cpus,
137 	&bin_attr_die_cpus_list,
138 #endif
139 	&bin_attr_package_cpus,
140 	&bin_attr_package_cpus_list,
141 #ifdef TOPOLOGY_BOOK_SYSFS
142 	&bin_attr_book_siblings,
143 	&bin_attr_book_siblings_list,
144 #endif
145 #ifdef TOPOLOGY_DRAWER_SYSFS
146 	&bin_attr_drawer_siblings,
147 	&bin_attr_drawer_siblings_list,
148 #endif
149 	NULL
150 };
151 
152 static struct attribute *default_attrs[] = {
153 	&dev_attr_physical_package_id.attr,
154 #ifdef TOPOLOGY_DIE_SYSFS
155 	&dev_attr_die_id.attr,
156 #endif
157 #ifdef TOPOLOGY_CLUSTER_SYSFS
158 	&dev_attr_cluster_id.attr,
159 #endif
160 	&dev_attr_core_id.attr,
161 #ifdef TOPOLOGY_BOOK_SYSFS
162 	&dev_attr_book_id.attr,
163 #endif
164 #ifdef TOPOLOGY_DRAWER_SYSFS
165 	&dev_attr_drawer_id.attr,
166 #endif
167 	&dev_attr_ppin.attr,
168 	NULL
169 };
170 
171 static umode_t topology_is_visible(struct kobject *kobj,
172 				   struct attribute *attr, int unused)
173 {
174 	if (attr == &dev_attr_ppin.attr && !topology_ppin(kobj_to_dev(kobj)->id))
175 		return 0;
176 
177 	return attr->mode;
178 }
179 
180 static const struct attribute_group topology_attr_group = {
181 	.attrs = default_attrs,
182 	.bin_attrs_new = bin_attrs,
183 	.is_visible = topology_is_visible,
184 	.name = "topology"
185 };
186 
187 /* Add/Remove cpu_topology interface for CPU device */
188 static int topology_add_dev(unsigned int cpu)
189 {
190 	struct device *dev = get_cpu_device(cpu);
191 
192 	return sysfs_create_group(&dev->kobj, &topology_attr_group);
193 }
194 
195 static int topology_remove_dev(unsigned int cpu)
196 {
197 	struct device *dev = get_cpu_device(cpu);
198 
199 	sysfs_remove_group(&dev->kobj, &topology_attr_group);
200 	return 0;
201 }
202 
203 static int __init topology_sysfs_init(void)
204 {
205 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
206 				 "base/topology:prepare", topology_add_dev,
207 				 topology_remove_dev);
208 }
209 
210 device_initcall(topology_sysfs_init);
211