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)                                       \
  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(core_id);
  52 static DEVICE_ATTR_RO(core_id);
  53
  54 define_siblings_read_func(thread_siblings, sibling_cpumask);
  55 static BIN_ATTR_RO(thread_siblings, 0);
  56 static BIN_ATTR_RO(thread_siblings_list, 0);
  57
  58 define_siblings_read_func(core_cpus, sibling_cpumask);
  59 static BIN_ATTR_RO(core_cpus, 0);
  60 static BIN_ATTR_RO(core_cpus_list, 0);
  61
  62 define_siblings_read_func(core_siblings, core_cpumask);
  63 static BIN_ATTR_RO(core_siblings, 0);
  64 static BIN_ATTR_RO(core_siblings_list, 0);
  65
  66 define_siblings_read_func(die_cpus, die_cpumask);
  67 static BIN_ATTR_RO(die_cpus, 0);
  68 static BIN_ATTR_RO(die_cpus_list, 0);
  69
  70 define_siblings_read_func(package_cpus, core_cpumask);
  71 static BIN_ATTR_RO(package_cpus, 0);
  72 static BIN_ATTR_RO(package_cpus_list, 0);
  73
  74 #ifdef CONFIG_SCHED_BOOK
  75 define_id_show_func(book_id);
  76 static DEVICE_ATTR_RO(book_id);
  77 define_siblings_read_func(book_siblings, book_cpumask);
  78 static BIN_ATTR_RO(book_siblings, 0);
  79 static BIN_ATTR_RO(book_siblings_list, 0);
  80 #endif
  81
  82 #ifdef CONFIG_SCHED_DRAWER
  83 define_id_show_func(drawer_id);
  84 static DEVICE_ATTR_RO(drawer_id);
  85 define_siblings_read_func(drawer_siblings, drawer_cpumask);
  86 static BIN_ATTR_RO(drawer_siblings, 0);
  87 static BIN_ATTR_RO(drawer_siblings_list, 0);
  88 #endif
  89
  90 static struct bin_attribute *bin_attrs[] = {
  91         &bin_attr_core_cpus,
  92         &bin_attr_core_cpus_list,
  93         &bin_attr_thread_siblings,
  94         &bin_attr_thread_siblings_list,
  95         &bin_attr_core_siblings,
  96         &bin_attr_core_siblings_list,
  97         &bin_attr_die_cpus,
  98         &bin_attr_die_cpus_list,
  99         &bin_attr_package_cpus,
 100         &bin_attr_package_cpus_list,
 101 #ifdef CONFIG_SCHED_BOOK
 102         &bin_attr_book_siblings,
 103         &bin_attr_book_siblings_list,
 104 #endif
 105 #ifdef CONFIG_SCHED_DRAWER
 106         &bin_attr_drawer_siblings,
 107         &bin_attr_drawer_siblings_list,
 108 #endif
 109         NULL
 110 };
 111
 112 static struct attribute *default_attrs[] = {
 113         &dev_attr_physical_package_id.attr,
 114         &dev_attr_die_id.attr,
 115         &dev_attr_core_id.attr,
 116 #ifdef CONFIG_SCHED_BOOK
 117         &dev_attr_book_id.attr,
 118 #endif
 119 #ifdef CONFIG_SCHED_DRAWER
 120         &dev_attr_drawer_id.attr,
 121 #endif
 122         NULL
 123 };
 124
 125 static const struct attribute_group topology_attr_group = {
 126         .attrs = default_attrs,
 127         .bin_attrs = bin_attrs,
 128         .name = "topology"
 129 };
 130
 131 /* Add/Remove cpu_topology interface for CPU device */
 132 static int topology_add_dev(unsigned int cpu)
 133 {
 134         struct device *dev = get_cpu_device(cpu);
 135
 136         return sysfs_create_group(&dev->kobj, &topology_attr_group);
 137 }
 138
 139 static int topology_remove_dev(unsigned int cpu)
 140 {
 141         struct device *dev = get_cpu_device(cpu);
 142
 143         sysfs_remove_group(&dev->kobj, &topology_attr_group);
 144         return 0;
 145 }
 146
 147 static int __init topology_sysfs_init(void)
 148 {
 149         return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
 150                                  "base/topology:prepare", topology_add_dev,
 151                                  topology_remove_dev);
 152 }
 153
 154 device_initcall(topology_sysfs_init);