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 sprintf(buf, "%d\n", topology_##name(dev->id));  \
  22 }
  23
  24 #define define_siblings_show_map(name, mask)                            \
  25 static ssize_t name##_show(struct device *dev,                          \
  26                            struct device_attribute *attr, char *buf)    \
  27 {                                                                       \
  28         return cpumap_print_to_pagebuf(false, buf, topology_##mask(dev->id));\
  29 }
  30
  31 #define define_siblings_show_list(name, mask)                           \
  32 static ssize_t name##_list_show(struct device *dev,                     \
  33                                 struct device_attribute *attr,          \
  34                                 char *buf)                              \
  35 {                                                                       \
  36         return cpumap_print_to_pagebuf(true, buf, topology_##mask(dev->id));\
  37 }
  38
  39 #define define_siblings_show_func(name, mask)   \
  40         define_siblings_show_map(name, mask);   \
  41         define_siblings_show_list(name, mask)
  42
  43 define_id_show_func(physical_package_id);
  44 static DEVICE_ATTR_RO(physical_package_id);
  45
  46 define_id_show_func(core_id);
  47 static DEVICE_ATTR_RO(core_id);
  48
  49 define_siblings_show_func(thread_siblings, sibling_cpumask);
  50 static DEVICE_ATTR_RO(thread_siblings);
  51 static DEVICE_ATTR_RO(thread_siblings_list);
  52
  53 define_siblings_show_func(core_siblings, core_cpumask);
  54 static DEVICE_ATTR_RO(core_siblings);
  55 static DEVICE_ATTR_RO(core_siblings_list);
  56
  57 #ifdef CONFIG_SCHED_BOOK
  58 define_id_show_func(book_id);
  59 static DEVICE_ATTR_RO(book_id);
  60 define_siblings_show_func(book_siblings, book_cpumask);
  61 static DEVICE_ATTR_RO(book_siblings);
  62 static DEVICE_ATTR_RO(book_siblings_list);
  63 #endif
  64
  65 #ifdef CONFIG_SCHED_DRAWER
  66 define_id_show_func(drawer_id);
  67 static DEVICE_ATTR_RO(drawer_id);
  68 define_siblings_show_func(drawer_siblings, drawer_cpumask);
  69 static DEVICE_ATTR_RO(drawer_siblings);
  70 static DEVICE_ATTR_RO(drawer_siblings_list);
  71 #endif
  72
  73 static struct attribute *default_attrs[] = {
  74         &dev_attr_physical_package_id.attr,
  75         &dev_attr_core_id.attr,
  76         &dev_attr_thread_siblings.attr,
  77         &dev_attr_thread_siblings_list.attr,
  78         &dev_attr_core_siblings.attr,
  79         &dev_attr_core_siblings_list.attr,
  80 #ifdef CONFIG_SCHED_BOOK
  81         &dev_attr_book_id.attr,
  82         &dev_attr_book_siblings.attr,
  83         &dev_attr_book_siblings_list.attr,
  84 #endif
  85 #ifdef CONFIG_SCHED_DRAWER
  86         &dev_attr_drawer_id.attr,
  87         &dev_attr_drawer_siblings.attr,
  88         &dev_attr_drawer_siblings_list.attr,
  89 #endif
  90         NULL
  91 };
  92
  93 static const struct attribute_group topology_attr_group = {
  94         .attrs = default_attrs,
  95         .name = "topology"
  96 };
  97
  98 /* Add/Remove cpu_topology interface for CPU device */
  99 static int topology_add_dev(unsigned int cpu)
 100 {
 101         struct device *dev = get_cpu_device(cpu);
 102
 103         return sysfs_create_group(&dev->kobj, &topology_attr_group);
 104 }
 105
 106 static int topology_remove_dev(unsigned int cpu)
 107 {
 108         struct device *dev = get_cpu_device(cpu);
 109
 110         sysfs_remove_group(&dev->kobj, &topology_attr_group);
 111         return 0;
 112 }
 113
 114 static int topology_sysfs_init(void)
 115 {
 116         return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
 117                                  "base/topology:prepare", topology_add_dev,
 118                                  topology_remove_dev);
 119 }
 120
 121 device_initcall(topology_sysfs_init);