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 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 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 BIN_ATTR_RO(thread_siblings, CPUMAP_FILE_MAX_BYTES);
82 static BIN_ATTR_RO(thread_siblings_list, CPULIST_FILE_MAX_BYTES);
83
84 define_siblings_read_func(core_cpus, sibling_cpumask);
85 static BIN_ATTR_RO(core_cpus, CPUMAP_FILE_MAX_BYTES);
86 static BIN_ATTR_RO(core_cpus_list, CPULIST_FILE_MAX_BYTES);
87
88 define_siblings_read_func(core_siblings, core_cpumask);
89 static BIN_ATTR_RO(core_siblings, CPUMAP_FILE_MAX_BYTES);
90 static 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 BIN_ATTR_RO(cluster_cpus, CPUMAP_FILE_MAX_BYTES);
95 static 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 BIN_ATTR_RO(die_cpus, CPUMAP_FILE_MAX_BYTES);
101 static BIN_ATTR_RO(die_cpus_list, CPULIST_FILE_MAX_BYTES);
102 #endif
103
104 define_siblings_read_func(package_cpus, core_cpumask);
105 static BIN_ATTR_RO(package_cpus, CPUMAP_FILE_MAX_BYTES);
106 static 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 BIN_ATTR_RO(book_siblings, CPUMAP_FILE_MAX_BYTES);
113 static 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 BIN_ATTR_RO(drawer_siblings, CPUMAP_FILE_MAX_BYTES);
121 static BIN_ATTR_RO(drawer_siblings_list, CPULIST_FILE_MAX_BYTES);
122 #endif
123
124 static struct bin_attribute *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
topology_is_visible(struct kobject * kobj,struct attribute * attr,int unused)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 = bin_attrs,
183 .is_visible = topology_is_visible,
184 .name = "topology"
185 };
186
187 /* Add/Remove cpu_topology interface for CPU device */
topology_add_dev(unsigned int cpu)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
topology_remove_dev(unsigned int cpu)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
topology_sysfs_init(void)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