drivers/base/topology.c

   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                                                                                 \
  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                                 const 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, "%d");
  46 static DEVICE_ATTR_RO(physical_package_id);
  47
  48 #ifdef TOPOLOGY_DIE_SYSFS
  49 define_id_show_func(die_id, "%d");
  50 static DEVICE_ATTR_RO(die_id);
  51 #endif
  52
  53 #ifdef TOPOLOGY_CLUSTER_SYSFS
  54 define_id_show_func(cluster_id, "%d");
  55 static DEVICE_ATTR_RO(cluster_id);
  56 #endif
  57
  58 define_id_show_func(core_id, "%d");
  59 static DEVICE_ATTR_RO(core_id);
  60
  61 define_id_show_func(ppin, "0x%llx");
  62 static DEVICE_ATTR_ADMIN_RO(ppin);
  63
  64 define_siblings_read_func(thread_siblings, sibling_cpumask);
  65 static const BIN_ATTR_RO(thread_siblings, CPUMAP_FILE_MAX_BYTES);
  66 static const BIN_ATTR_RO(thread_siblings_list, CPULIST_FILE_MAX_BYTES);
  67
  68 define_siblings_read_func(core_cpus, sibling_cpumask);
  69 static const BIN_ATTR_RO(core_cpus, CPUMAP_FILE_MAX_BYTES);
  70 static const BIN_ATTR_RO(core_cpus_list, CPULIST_FILE_MAX_BYTES);
  71
  72 define_siblings_read_func(core_siblings, core_cpumask);
  73 static const BIN_ATTR_RO(core_siblings, CPUMAP_FILE_MAX_BYTES);
  74 static const BIN_ATTR_RO(core_siblings_list, CPULIST_FILE_MAX_BYTES);
  75
  76 #ifdef TOPOLOGY_CLUSTER_SYSFS
  77 define_siblings_read_func(cluster_cpus, cluster_cpumask);
  78 static const BIN_ATTR_RO(cluster_cpus, CPUMAP_FILE_MAX_BYTES);
  79 static const BIN_ATTR_RO(cluster_cpus_list, CPULIST_FILE_MAX_BYTES);
  80 #endif
  81
  82 #ifdef TOPOLOGY_DIE_SYSFS
  83 define_siblings_read_func(die_cpus, die_cpumask);
  84 static const BIN_ATTR_RO(die_cpus, CPUMAP_FILE_MAX_BYTES);
  85 static const BIN_ATTR_RO(die_cpus_list, CPULIST_FILE_MAX_BYTES);
  86 #endif
  87
  88 define_siblings_read_func(package_cpus, core_cpumask);
  89 static const BIN_ATTR_RO(package_cpus, CPUMAP_FILE_MAX_BYTES);
  90 static const BIN_ATTR_RO(package_cpus_list, CPULIST_FILE_MAX_BYTES);
  91
  92 #ifdef TOPOLOGY_BOOK_SYSFS
  93 define_id_show_func(book_id, "%d");
  94 static DEVICE_ATTR_RO(book_id);
  95 define_siblings_read_func(book_siblings, book_cpumask);
  96 static const BIN_ATTR_RO(book_siblings, CPUMAP_FILE_MAX_BYTES);
  97 static const BIN_ATTR_RO(book_siblings_list, CPULIST_FILE_MAX_BYTES);
  98 #endif
  99
 100 #ifdef TOPOLOGY_DRAWER_SYSFS
 101 define_id_show_func(drawer_id, "%d");
 102 static DEVICE_ATTR_RO(drawer_id);
 103 define_siblings_read_func(drawer_siblings, drawer_cpumask);
 104 static const BIN_ATTR_RO(drawer_siblings, CPUMAP_FILE_MAX_BYTES);
 105 static const BIN_ATTR_RO(drawer_siblings_list, CPULIST_FILE_MAX_BYTES);
 106 #endif
 107
 108 static const struct bin_attribute *const bin_attrs[] = {
 109         &bin_attr_core_cpus,
 110         &bin_attr_core_cpus_list,
 111         &bin_attr_thread_siblings,
 112         &bin_attr_thread_siblings_list,
 113         &bin_attr_core_siblings,
 114         &bin_attr_core_siblings_list,
 115 #ifdef TOPOLOGY_CLUSTER_SYSFS
 116         &bin_attr_cluster_cpus,
 117         &bin_attr_cluster_cpus_list,
 118 #endif
 119 #ifdef TOPOLOGY_DIE_SYSFS
 120         &bin_attr_die_cpus,
 121         &bin_attr_die_cpus_list,
 122 #endif
 123         &bin_attr_package_cpus,
 124         &bin_attr_package_cpus_list,
 125 #ifdef TOPOLOGY_BOOK_SYSFS
 126         &bin_attr_book_siblings,
 127         &bin_attr_book_siblings_list,
 128 #endif
 129 #ifdef TOPOLOGY_DRAWER_SYSFS
 130         &bin_attr_drawer_siblings,
 131         &bin_attr_drawer_siblings_list,
 132 #endif
 133         NULL
 134 };
 135
 136 static struct attribute *default_attrs[] = {
 137         &dev_attr_physical_package_id.attr,
 138 #ifdef TOPOLOGY_DIE_SYSFS
 139         &dev_attr_die_id.attr,
 140 #endif
 141 #ifdef TOPOLOGY_CLUSTER_SYSFS
 142         &dev_attr_cluster_id.attr,
 143 #endif
 144         &dev_attr_core_id.attr,
 145 #ifdef TOPOLOGY_BOOK_SYSFS
 146         &dev_attr_book_id.attr,
 147 #endif
 148 #ifdef TOPOLOGY_DRAWER_SYSFS
 149         &dev_attr_drawer_id.attr,
 150 #endif
 151         &dev_attr_ppin.attr,
 152         NULL
 153 };
 154
 155 static umode_t topology_is_visible(struct kobject *kobj,
 156                                    struct attribute *attr, int unused)
 157 {
 158         if (attr == &dev_attr_ppin.attr && !topology_ppin(kobj_to_dev(kobj)->id))
 159                 return 0;
 160
 161         return attr->mode;
 162 }
 163
 164 static const struct attribute_group topology_attr_group = {
 165         .attrs = default_attrs,
 166         .bin_attrs_new = bin_attrs,
 167         .is_visible = topology_is_visible,
 168         .name = "topology"
 169 };
 170
 171 /* Add/Remove cpu_topology interface for CPU device */
 172 static int topology_add_dev(unsigned int cpu)
 173 {
 174         struct device *dev = get_cpu_device(cpu);
 175
 176         return sysfs_create_group(&dev->kobj, &topology_attr_group);
 177 }
 178
 179 static int topology_remove_dev(unsigned int cpu)
 180 {
 181         struct device *dev = get_cpu_device(cpu);
 182
 183         sysfs_remove_group(&dev->kobj, &topology_attr_group);
 184         return 0;
 185 }
 186
 187 static int __init topology_sysfs_init(void)
 188 {
 189         return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
 190                                  "base/topology:prepare", topology_add_dev,
 191                                  topology_remove_dev);
 192 }
 193
 194 device_initcall(topology_sysfs_init);