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) \
18static 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) \
25static 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 \
43static 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
61define_id_show_func(physical_package_id, "%d");
62static DEVICE_ATTR_RO(physical_package_id);
63
64#ifdef TOPOLOGY_DIE_SYSFS
65define_id_show_func(die_id, "%d");
66static DEVICE_ATTR_RO(die_id);
67#endif
68
69#ifdef TOPOLOGY_CLUSTER_SYSFS
70define_id_show_func(cluster_id, "%d");
71static DEVICE_ATTR_RO(cluster_id);
72#endif
73
74define_id_show_func(core_id, "%d");
75static DEVICE_ATTR_RO(core_id);
76
77define_id_show_func(ppin, "0x%llx");
78static DEVICE_ATTR_ADMIN_RO(ppin);
79
80define_siblings_read_func(thread_siblings, sibling_cpumask);
81static const BIN_ATTR_RO(thread_siblings, CPUMAP_FILE_MAX_BYTES);
82static const BIN_ATTR_RO(thread_siblings_list, CPULIST_FILE_MAX_BYTES);
83
84define_siblings_read_func(core_cpus, sibling_cpumask);
85static const BIN_ATTR_RO(core_cpus, CPUMAP_FILE_MAX_BYTES);
86static const BIN_ATTR_RO(core_cpus_list, CPULIST_FILE_MAX_BYTES);
87
88define_siblings_read_func(core_siblings, core_cpumask);
89static const BIN_ATTR_RO(core_siblings, CPUMAP_FILE_MAX_BYTES);
90static const BIN_ATTR_RO(core_siblings_list, CPULIST_FILE_MAX_BYTES);
91
92#ifdef TOPOLOGY_CLUSTER_SYSFS
93define_siblings_read_func(cluster_cpus, cluster_cpumask);
94static const BIN_ATTR_RO(cluster_cpus, CPUMAP_FILE_MAX_BYTES);
95static const BIN_ATTR_RO(cluster_cpus_list, CPULIST_FILE_MAX_BYTES);
96#endif
97
98#ifdef TOPOLOGY_DIE_SYSFS
99define_siblings_read_func(die_cpus, die_cpumask);
100static const BIN_ATTR_RO(die_cpus, CPUMAP_FILE_MAX_BYTES);
101static const BIN_ATTR_RO(die_cpus_list, CPULIST_FILE_MAX_BYTES);
102#endif
103
104define_siblings_read_func(package_cpus, core_cpumask);
105static const BIN_ATTR_RO(package_cpus, CPUMAP_FILE_MAX_BYTES);
106static const BIN_ATTR_RO(package_cpus_list, CPULIST_FILE_MAX_BYTES);
107
108#ifdef TOPOLOGY_BOOK_SYSFS
109define_id_show_func(book_id, "%d");
110static DEVICE_ATTR_RO(book_id);
111define_siblings_read_func(book_siblings, book_cpumask);
112static const BIN_ATTR_RO(book_siblings, CPUMAP_FILE_MAX_BYTES);
113static const BIN_ATTR_RO(book_siblings_list, CPULIST_FILE_MAX_BYTES);
114#endif
115
116#ifdef TOPOLOGY_DRAWER_SYSFS
117define_id_show_func(drawer_id, "%d");
118static DEVICE_ATTR_RO(drawer_id);
119define_siblings_read_func(drawer_siblings, drawer_cpumask);
120static const BIN_ATTR_RO(drawer_siblings, CPUMAP_FILE_MAX_BYTES);
121static const BIN_ATTR_RO(drawer_siblings_list, CPULIST_FILE_MAX_BYTES);
122#endif
123
124static 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
152static 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
171static 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
180static 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 */
188static int topology_add_dev(unsigned int cpu)
189{
190 struct device *dev = get_cpu_device(cpu);
191
192 return sysfs_create_group(kobj: &dev->kobj, grp: &topology_attr_group);
193}
194
195static int topology_remove_dev(unsigned int cpu)
196{
197 struct device *dev = get_cpu_device(cpu);
198
199 sysfs_remove_group(kobj: &dev->kobj, grp: &topology_attr_group);
200 return 0;
201}
202
203static int __init topology_sysfs_init(void)
204{
205 return cpuhp_setup_state(state: CPUHP_TOPOLOGY_PREPARE,
206 name: "base/topology:prepare", startup: topology_add_dev,
207 teardown: topology_remove_dev);
208}
209
210device_initcall(topology_sysfs_init);
211
212DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
213EXPORT_PER_CPU_SYMBOL_GPL(cpu_scale);
214
215void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
216{
217 per_cpu(cpu_scale, cpu) = capacity;
218}
219
220static ssize_t cpu_capacity_show(struct device *dev,
221 struct device_attribute *attr,
222 char *buf)
223{
224 struct cpu *cpu = container_of(dev, struct cpu, dev);
225
226 return sysfs_emit(buf, fmt: "%lu\n", topology_get_cpu_scale(cpu: cpu->dev.id));
227}
228
229static DEVICE_ATTR_RO(cpu_capacity);
230
231static int cpu_capacity_sysctl_add(unsigned int cpu)
232{
233 struct device *cpu_dev = get_cpu_device(cpu);
234
235 if (!cpu_dev)
236 return -ENOENT;
237
238 device_create_file(device: cpu_dev, entry: &dev_attr_cpu_capacity);
239
240 return 0;
241}
242
243static int cpu_capacity_sysctl_remove(unsigned int cpu)
244{
245 struct device *cpu_dev = get_cpu_device(cpu);
246
247 if (!cpu_dev)
248 return -ENOENT;
249
250 device_remove_file(dev: cpu_dev, attr: &dev_attr_cpu_capacity);
251
252 return 0;
253}
254
255static int register_cpu_capacity_sysctl(void)
256{
257 cpuhp_setup_state(state: CPUHP_AP_ONLINE_DYN, name: "topology/cpu-capacity",
258 startup: cpu_capacity_sysctl_add, teardown: cpu_capacity_sysctl_remove);
259
260 return 0;
261}
262subsys_initcall(register_cpu_capacity_sysctl);
263