| 1 | /* |
| 2 | * driver/base/topology.c - Populate sysfs with cpu topology information |
| 3 | * |
| 4 | * Written by: Zhang Yanmin, Intel Corporation |
| 5 | * |
| 6 | * Copyright (C) 2006, Intel Corp. |
| 7 | * |
| 8 | * All rights reserved. |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU General Public License as published by |
| 12 | * the Free Software Foundation; either version 2 of the License, or |
| 13 | * (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, but |
| 16 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| 18 | * NON INFRINGEMENT. See the GNU General Public License for more |
| 19 | * details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with this program; if not, write to the Free Software |
| 23 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 24 | * |
| 25 | */ |
| 26 | #include <linux/mm.h> |
| 27 | #include <linux/cpu.h> |
| 28 | #include <linux/module.h> |
| 29 | #include <linux/hardirq.h> |
| 30 | #include <linux/topology.h> |
| 31 | |
| 32 | #define define_id_show_func(name) \ |
| 33 | static ssize_t name##_show(struct device *dev, \ |
| 34 | struct device_attribute *attr, char *buf) \ |
| 35 | { \ |
| 36 | return sprintf(buf, "%d\n", topology_##name(dev->id)); \ |
| 37 | } |
| 38 | |
| 39 | #define define_siblings_show_map(name, mask) \ |
| 40 | static ssize_t name##_show(struct device *dev, \ |
| 41 | struct device_attribute *attr, char *buf) \ |
| 42 | { \ |
| 43 | return cpumap_print_to_pagebuf(false, buf, topology_##mask(dev->id));\ |
| 44 | } |
| 45 | |
| 46 | #define define_siblings_show_list(name, mask) \ |
| 47 | static ssize_t name##_list_show(struct device *dev, \ |
| 48 | struct device_attribute *attr, \ |
| 49 | char *buf) \ |
| 50 | { \ |
| 51 | return cpumap_print_to_pagebuf(true, buf, topology_##mask(dev->id));\ |
| 52 | } |
| 53 | |
| 54 | #define define_siblings_show_func(name, mask) \ |
| 55 | define_siblings_show_map(name, mask); \ |
| 56 | define_siblings_show_list(name, mask) |
| 57 | |
| 58 | define_id_show_func(physical_package_id); |
| 59 | static DEVICE_ATTR_RO(physical_package_id); |
| 60 | |
| 61 | define_id_show_func(core_id); |
| 62 | static DEVICE_ATTR_RO(core_id); |
| 63 | |
| 64 | define_siblings_show_func(thread_siblings, sibling_cpumask); |
| 65 | static DEVICE_ATTR_RO(thread_siblings); |
| 66 | static DEVICE_ATTR_RO(thread_siblings_list); |
| 67 | |
| 68 | define_siblings_show_func(core_siblings, core_cpumask); |
| 69 | static DEVICE_ATTR_RO(core_siblings); |
| 70 | static DEVICE_ATTR_RO(core_siblings_list); |
| 71 | |
| 72 | #ifdef CONFIG_SCHED_BOOK |
| 73 | define_id_show_func(book_id); |
| 74 | static DEVICE_ATTR_RO(book_id); |
| 75 | define_siblings_show_func(book_siblings, book_cpumask); |
| 76 | static DEVICE_ATTR_RO(book_siblings); |
| 77 | static DEVICE_ATTR_RO(book_siblings_list); |
| 78 | #endif |
| 79 | |
| 80 | static struct attribute *default_attrs[] = { |
| 81 | &dev_attr_physical_package_id.attr, |
| 82 | &dev_attr_core_id.attr, |
| 83 | &dev_attr_thread_siblings.attr, |
| 84 | &dev_attr_thread_siblings_list.attr, |
| 85 | &dev_attr_core_siblings.attr, |
| 86 | &dev_attr_core_siblings_list.attr, |
| 87 | #ifdef CONFIG_SCHED_BOOK |
| 88 | &dev_attr_book_id.attr, |
| 89 | &dev_attr_book_siblings.attr, |
| 90 | &dev_attr_book_siblings_list.attr, |
| 91 | #endif |
| 92 | NULL |
| 93 | }; |
| 94 | |
| 95 | static struct attribute_group topology_attr_group = { |
| 96 | .attrs = default_attrs, |
| 97 | .name = "topology" |
| 98 | }; |
| 99 | |
| 100 | /* Add/Remove cpu_topology interface for CPU device */ |
| 101 | static int topology_add_dev(unsigned int cpu) |
| 102 | { |
| 103 | struct device *dev = get_cpu_device(cpu); |
| 104 | |
| 105 | return sysfs_create_group(&dev->kobj, &topology_attr_group); |
| 106 | } |
| 107 | |
| 108 | static void topology_remove_dev(unsigned int cpu) |
| 109 | { |
| 110 | struct device *dev = get_cpu_device(cpu); |
| 111 | |
| 112 | sysfs_remove_group(&dev->kobj, &topology_attr_group); |
| 113 | } |
| 114 | |
| 115 | static int topology_cpu_callback(struct notifier_block *nfb, |
| 116 | unsigned long action, void *hcpu) |
| 117 | { |
| 118 | unsigned int cpu = (unsigned long)hcpu; |
| 119 | int rc = 0; |
| 120 | |
| 121 | switch (action) { |
| 122 | case CPU_UP_PREPARE: |
| 123 | case CPU_UP_PREPARE_FROZEN: |
| 124 | rc = topology_add_dev(cpu); |
| 125 | break; |
| 126 | case CPU_UP_CANCELED: |
| 127 | case CPU_UP_CANCELED_FROZEN: |
| 128 | case CPU_DEAD: |
| 129 | case CPU_DEAD_FROZEN: |
| 130 | topology_remove_dev(cpu); |
| 131 | break; |
| 132 | } |
| 133 | return notifier_from_errno(rc); |
| 134 | } |
| 135 | |
| 136 | static int topology_sysfs_init(void) |
| 137 | { |
| 138 | int cpu; |
| 139 | int rc = 0; |
| 140 | |
| 141 | cpu_notifier_register_begin(); |
| 142 | |
| 143 | for_each_online_cpu(cpu) { |
| 144 | rc = topology_add_dev(cpu); |
| 145 | if (rc) |
| 146 | goto out; |
| 147 | } |
| 148 | __hotcpu_notifier(topology_cpu_callback, 0); |
| 149 | |
| 150 | out: |
| 151 | cpu_notifier_register_done(); |
| 152 | return rc; |
| 153 | } |
| 154 | |
| 155 | device_initcall(topology_sysfs_init); |