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)					\
18 static ssize_t name##_show(struct device *dev,				\
19 			   struct device_attribute *attr, char *buf)	\
20 {									\
21 	return sysfs_emit(buf, "%d\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 										\
31 	return cpumap_print_bitmask_to_buf(buf, topology_##mask(dev->id),	\
32 					   off, count);                         \
33 }										\
34 										\
35 static ssize_t name##_list_read(struct file *file, struct kobject *kobj,	\
36 				struct bin_attribute *attr, char *buf,		\
37 				loff_t off, size_t count)			\
38 {										\
39 	struct device *dev = kobj_to_dev(kobj);					\
40 										\
41 	return cpumap_print_list_to_buf(buf, topology_##mask(dev->id),		\
42 					off, count);				\
43 }
44 
45 define_id_show_func(physical_package_id);
46 static DEVICE_ATTR_RO(physical_package_id);
47 
48 define_id_show_func(die_id);
49 static DEVICE_ATTR_RO(die_id);
50 
51 define_id_show_func(cluster_id);
52 static DEVICE_ATTR_RO(cluster_id);
53 
54 define_id_show_func(core_id);
55 static DEVICE_ATTR_RO(core_id);
56 
57 define_siblings_read_func(thread_siblings, sibling_cpumask);
58 static BIN_ATTR_RO(thread_siblings, 0);
59 static BIN_ATTR_RO(thread_siblings_list, 0);
60 
61 define_siblings_read_func(core_cpus, sibling_cpumask);
62 static BIN_ATTR_RO(core_cpus, 0);
63 static BIN_ATTR_RO(core_cpus_list, 0);
64 
65 define_siblings_read_func(core_siblings, core_cpumask);
66 static BIN_ATTR_RO(core_siblings, 0);
67 static BIN_ATTR_RO(core_siblings_list, 0);
68 
69 define_siblings_read_func(cluster_cpus, cluster_cpumask);
70 static BIN_ATTR_RO(cluster_cpus, 0);
71 static BIN_ATTR_RO(cluster_cpus_list, 0);
72 
73 define_siblings_read_func(die_cpus, die_cpumask);
74 static BIN_ATTR_RO(die_cpus, 0);
75 static BIN_ATTR_RO(die_cpus_list, 0);
76 
77 define_siblings_read_func(package_cpus, core_cpumask);
78 static BIN_ATTR_RO(package_cpus, 0);
79 static BIN_ATTR_RO(package_cpus_list, 0);
80 
81 #ifdef CONFIG_SCHED_BOOK
82 define_id_show_func(book_id);
83 static DEVICE_ATTR_RO(book_id);
84 define_siblings_read_func(book_siblings, book_cpumask);
85 static BIN_ATTR_RO(book_siblings, 0);
86 static BIN_ATTR_RO(book_siblings_list, 0);
87 #endif
88 
89 #ifdef CONFIG_SCHED_DRAWER
90 define_id_show_func(drawer_id);
91 static DEVICE_ATTR_RO(drawer_id);
92 define_siblings_read_func(drawer_siblings, drawer_cpumask);
93 static BIN_ATTR_RO(drawer_siblings, 0);
94 static BIN_ATTR_RO(drawer_siblings_list, 0);
95 #endif
96 
97 static struct bin_attribute *bin_attrs[] = {
98 	&bin_attr_core_cpus,
99 	&bin_attr_core_cpus_list,
100 	&bin_attr_thread_siblings,
101 	&bin_attr_thread_siblings_list,
102 	&bin_attr_core_siblings,
103 	&bin_attr_core_siblings_list,
104 	&bin_attr_cluster_cpus,
105 	&bin_attr_cluster_cpus_list,
106 	&bin_attr_die_cpus,
107 	&bin_attr_die_cpus_list,
108 	&bin_attr_package_cpus,
109 	&bin_attr_package_cpus_list,
110 #ifdef CONFIG_SCHED_BOOK
111 	&bin_attr_book_siblings,
112 	&bin_attr_book_siblings_list,
113 #endif
114 #ifdef CONFIG_SCHED_DRAWER
115 	&bin_attr_drawer_siblings,
116 	&bin_attr_drawer_siblings_list,
117 #endif
118 	NULL
119 };
120 
121 static struct attribute *default_attrs[] = {
122 	&dev_attr_physical_package_id.attr,
123 	&dev_attr_die_id.attr,
124 	&dev_attr_cluster_id.attr,
125 	&dev_attr_core_id.attr,
126 #ifdef CONFIG_SCHED_BOOK
127 	&dev_attr_book_id.attr,
128 #endif
129 #ifdef CONFIG_SCHED_DRAWER
130 	&dev_attr_drawer_id.attr,
131 #endif
132 	NULL
133 };
134 
135 static const struct attribute_group topology_attr_group = {
136 	.attrs = default_attrs,
137 	.bin_attrs = bin_attrs,
138 	.name = "topology"
139 };
140 
141 /* Add/Remove cpu_topology interface for CPU device */
topology_add_dev(unsigned int cpu)142 static int topology_add_dev(unsigned int cpu)
143 {
144 	struct device *dev = get_cpu_device(cpu);
145 
146 	return sysfs_create_group(&dev->kobj, &topology_attr_group);
147 }
148 
topology_remove_dev(unsigned int cpu)149 static int topology_remove_dev(unsigned int cpu)
150 {
151 	struct device *dev = get_cpu_device(cpu);
152 
153 	sysfs_remove_group(&dev->kobj, &topology_attr_group);
154 	return 0;
155 }
156 
topology_sysfs_init(void)157 static int __init topology_sysfs_init(void)
158 {
159 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
160 				 "base/topology:prepare", topology_add_dev,
161 				 topology_remove_dev);
162 }
163 
164 device_initcall(topology_sysfs_init);
165