Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * drivers/base/cpu.c - basic CPU class support |
| 3 | */ |
| 4 | |
| 5 | #include <linux/sysdev.h> |
| 6 | #include <linux/module.h> |
| 7 | #include <linux/init.h> |
Al Viro | f6a5703 | 2006-10-18 01:47:25 -0400 | [diff] [blame] | 8 | #include <linux/sched.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include <linux/cpu.h> |
| 10 | #include <linux/topology.h> |
| 11 | #include <linux/device.h> |
KAMEZAWA Hiroyuki | 76b67ed9 | 2006-06-27 02:53:41 -0700 | [diff] [blame] | 12 | #include <linux/node.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | |
Ben Dooks | a1bdc7a | 2005-10-13 17:54:41 +0100 | [diff] [blame] | 14 | #include "base.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | |
| 16 | struct sysdev_class cpu_sysdev_class = { |
Kay Sievers | af5ca3f | 2007-12-20 02:09:39 +0100 | [diff] [blame] | 17 | .name = "cpu", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | }; |
| 19 | EXPORT_SYMBOL(cpu_sysdev_class); |
| 20 | |
Mike Travis | e37d05d | 2008-05-01 04:35:16 -0700 | [diff] [blame] | 21 | static DEFINE_PER_CPU(struct sys_device *, cpu_sys_devices); |
Ashok Raj | ad74557 | 2005-10-30 14:59:49 -0800 | [diff] [blame] | 22 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #ifdef CONFIG_HOTPLUG_CPU |
Andi Kleen | 4a0b2b4 | 2008-07-01 18:48:41 +0200 | [diff] [blame] | 24 | static ssize_t show_online(struct sys_device *dev, struct sysdev_attribute *attr, |
| 25 | char *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | { |
| 27 | struct cpu *cpu = container_of(dev, struct cpu, sysdev); |
| 28 | |
| 29 | return sprintf(buf, "%u\n", !!cpu_online(cpu->sysdev.id)); |
| 30 | } |
| 31 | |
Andi Kleen | 4a0b2b4 | 2008-07-01 18:48:41 +0200 | [diff] [blame] | 32 | static ssize_t __ref store_online(struct sys_device *dev, struct sysdev_attribute *attr, |
| 33 | const char *buf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | { |
| 35 | struct cpu *cpu = container_of(dev, struct cpu, sysdev); |
| 36 | ssize_t ret; |
| 37 | |
| 38 | switch (buf[0]) { |
| 39 | case '0': |
| 40 | ret = cpu_down(cpu->sysdev.id); |
| 41 | if (!ret) |
Kay Sievers | 312c004 | 2005-11-16 09:00:00 +0100 | [diff] [blame] | 42 | kobject_uevent(&dev->kobj, KOBJ_OFFLINE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | break; |
| 44 | case '1': |
Ashok Raj | 34f361a | 2006-03-25 03:08:18 -0800 | [diff] [blame] | 45 | ret = cpu_up(cpu->sysdev.id); |
Nathan Lynch | fb69c39 | 2005-06-25 14:55:05 -0700 | [diff] [blame] | 46 | if (!ret) |
Kay Sievers | 312c004 | 2005-11-16 09:00:00 +0100 | [diff] [blame] | 47 | kobject_uevent(&dev->kobj, KOBJ_ONLINE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | break; |
| 49 | default: |
| 50 | ret = -EINVAL; |
| 51 | } |
| 52 | |
| 53 | if (ret >= 0) |
| 54 | ret = count; |
| 55 | return ret; |
| 56 | } |
Ulrich Drepper | 9eb3ff4 | 2007-07-31 00:38:16 -0700 | [diff] [blame] | 57 | static SYSDEV_ATTR(online, 0644, show_online, store_online); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | |
Sam Ravnborg | 6c84740 | 2008-03-04 15:09:05 -0800 | [diff] [blame] | 59 | static void __cpuinit register_cpu_control(struct cpu *cpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | { |
| 61 | sysdev_create_file(&cpu->sysdev, &attr_online); |
| 62 | } |
KAMEZAWA Hiroyuki | 76b67ed9 | 2006-06-27 02:53:41 -0700 | [diff] [blame] | 63 | void unregister_cpu(struct cpu *cpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | { |
Ashok Raj | ad74557 | 2005-10-30 14:59:49 -0800 | [diff] [blame] | 65 | int logical_cpu = cpu->sysdev.id; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | |
KAMEZAWA Hiroyuki | 76b67ed9 | 2006-06-27 02:53:41 -0700 | [diff] [blame] | 67 | unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu)); |
| 68 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | sysdev_remove_file(&cpu->sysdev, &attr_online); |
| 70 | |
| 71 | sysdev_unregister(&cpu->sysdev); |
Mike Travis | e37d05d | 2008-05-01 04:35:16 -0700 | [diff] [blame] | 72 | per_cpu(cpu_sys_devices, logical_cpu) = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | return; |
| 74 | } |
| 75 | #else /* ... !CONFIG_HOTPLUG_CPU */ |
| 76 | static inline void register_cpu_control(struct cpu *cpu) |
| 77 | { |
| 78 | } |
| 79 | #endif /* CONFIG_HOTPLUG_CPU */ |
| 80 | |
Vivek Goyal | 51be560 | 2006-01-09 20:51:42 -0800 | [diff] [blame] | 81 | #ifdef CONFIG_KEXEC |
| 82 | #include <linux/kexec.h> |
| 83 | |
Andi Kleen | 4a0b2b4 | 2008-07-01 18:48:41 +0200 | [diff] [blame] | 84 | static ssize_t show_crash_notes(struct sys_device *dev, struct sysdev_attribute *attr, |
| 85 | char *buf) |
Vivek Goyal | 51be560 | 2006-01-09 20:51:42 -0800 | [diff] [blame] | 86 | { |
| 87 | struct cpu *cpu = container_of(dev, struct cpu, sysdev); |
| 88 | ssize_t rc; |
| 89 | unsigned long long addr; |
| 90 | int cpunum; |
| 91 | |
| 92 | cpunum = cpu->sysdev.id; |
| 93 | |
| 94 | /* |
| 95 | * Might be reading other cpu's data based on which cpu read thread |
| 96 | * has been scheduled. But cpu data (memory) is allocated once during |
| 97 | * boot up and this data does not change there after. Hence this |
| 98 | * operation should be safe. No locking required. |
| 99 | */ |
Vivek Goyal | 51be560 | 2006-01-09 20:51:42 -0800 | [diff] [blame] | 100 | addr = __pa(per_cpu_ptr(crash_notes, cpunum)); |
| 101 | rc = sprintf(buf, "%Lx\n", addr); |
Vivek Goyal | 51be560 | 2006-01-09 20:51:42 -0800 | [diff] [blame] | 102 | return rc; |
| 103 | } |
| 104 | static SYSDEV_ATTR(crash_notes, 0400, show_crash_notes, NULL); |
| 105 | #endif |
| 106 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | /* |
Mike Travis | 9d1fe323 | 2008-04-08 11:43:04 -0700 | [diff] [blame] | 108 | * Print cpu online, possible, present, and system maps |
| 109 | */ |
Rusty Russell | f7df8ed | 2009-01-10 21:58:09 -0800 | [diff] [blame^] | 110 | static ssize_t print_cpus_map(char *buf, const struct cpumask *map) |
Mike Travis | 9d1fe323 | 2008-04-08 11:43:04 -0700 | [diff] [blame] | 111 | { |
Rusty Russell | 29c0177 | 2008-12-13 21:20:25 +1030 | [diff] [blame] | 112 | int n = cpulist_scnprintf(buf, PAGE_SIZE-2, map); |
Mike Travis | 9d1fe323 | 2008-04-08 11:43:04 -0700 | [diff] [blame] | 113 | |
| 114 | buf[n++] = '\n'; |
| 115 | buf[n] = '\0'; |
| 116 | return n; |
| 117 | } |
| 118 | |
| 119 | #define print_cpus_func(type) \ |
| 120 | static ssize_t print_cpus_##type(struct sysdev_class *class, char *buf) \ |
| 121 | { \ |
| 122 | return print_cpus_map(buf, &cpu_##type##_map); \ |
| 123 | } \ |
Mike Travis | 143aa5c | 2008-05-12 21:21:13 +0200 | [diff] [blame] | 124 | static struct sysdev_class_attribute attr_##type##_map = \ |
Mike Travis | 9d1fe323 | 2008-04-08 11:43:04 -0700 | [diff] [blame] | 125 | _SYSDEV_CLASS_ATTR(type, 0444, print_cpus_##type, NULL) |
| 126 | |
| 127 | print_cpus_func(online); |
| 128 | print_cpus_func(possible); |
| 129 | print_cpus_func(present); |
| 130 | |
Mike Travis | e057d7a | 2008-12-15 20:26:48 -0800 | [diff] [blame] | 131 | /* |
| 132 | * Print values for NR_CPUS and offlined cpus |
| 133 | */ |
| 134 | static ssize_t print_cpus_kernel_max(struct sysdev_class *class, char *buf) |
| 135 | { |
Mike Travis | 8fd2d2d | 2008-12-31 18:08:48 -0800 | [diff] [blame] | 136 | int n = snprintf(buf, PAGE_SIZE-2, "%d\n", NR_CPUS - 1); |
Mike Travis | e057d7a | 2008-12-15 20:26:48 -0800 | [diff] [blame] | 137 | return n; |
| 138 | } |
| 139 | static SYSDEV_CLASS_ATTR(kernel_max, 0444, print_cpus_kernel_max, NULL); |
| 140 | |
| 141 | /* arch-optional setting to enable display of offline cpus >= nr_cpu_ids */ |
| 142 | unsigned int total_cpus; |
| 143 | |
| 144 | static ssize_t print_cpus_offline(struct sysdev_class *class, char *buf) |
| 145 | { |
| 146 | int n = 0, len = PAGE_SIZE-2; |
| 147 | cpumask_var_t offline; |
| 148 | |
| 149 | /* display offline cpus < nr_cpu_ids */ |
| 150 | if (!alloc_cpumask_var(&offline, GFP_KERNEL)) |
| 151 | return -ENOMEM; |
| 152 | cpumask_complement(offline, cpu_online_mask); |
| 153 | n = cpulist_scnprintf(buf, len, offline); |
| 154 | free_cpumask_var(offline); |
| 155 | |
| 156 | /* display offline cpus >= nr_cpu_ids */ |
| 157 | if (total_cpus && nr_cpu_ids < total_cpus) { |
| 158 | if (n && n < len) |
| 159 | buf[n++] = ','; |
| 160 | |
| 161 | if (nr_cpu_ids == total_cpus-1) |
| 162 | n += snprintf(&buf[n], len - n, "%d", nr_cpu_ids); |
| 163 | else |
| 164 | n += snprintf(&buf[n], len - n, "%d-%d", |
| 165 | nr_cpu_ids, total_cpus-1); |
| 166 | } |
| 167 | |
| 168 | n += snprintf(&buf[n], len - n, "\n"); |
| 169 | return n; |
| 170 | } |
| 171 | static SYSDEV_CLASS_ATTR(offline, 0444, print_cpus_offline, NULL); |
| 172 | |
Mike Travis | 143aa5c | 2008-05-12 21:21:13 +0200 | [diff] [blame] | 173 | static struct sysdev_class_attribute *cpu_state_attr[] = { |
Mike Travis | 9d1fe323 | 2008-04-08 11:43:04 -0700 | [diff] [blame] | 174 | &attr_online_map, |
| 175 | &attr_possible_map, |
| 176 | &attr_present_map, |
Mike Travis | e057d7a | 2008-12-15 20:26:48 -0800 | [diff] [blame] | 177 | &attr_kernel_max, |
| 178 | &attr_offline, |
Mike Travis | 9d1fe323 | 2008-04-08 11:43:04 -0700 | [diff] [blame] | 179 | }; |
| 180 | |
| 181 | static int cpu_states_init(void) |
| 182 | { |
| 183 | int i; |
| 184 | int err = 0; |
| 185 | |
| 186 | for (i = 0; i < ARRAY_SIZE(cpu_state_attr); i++) { |
| 187 | int ret; |
| 188 | ret = sysdev_class_create_file(&cpu_sysdev_class, |
| 189 | cpu_state_attr[i]); |
| 190 | if (!err) |
| 191 | err = ret; |
| 192 | } |
| 193 | return err; |
| 194 | } |
| 195 | |
| 196 | /* |
Robert P. J. Day | 405ae7d | 2007-02-17 19:13:42 +0100 | [diff] [blame] | 197 | * register_cpu - Setup a sysfs device for a CPU. |
Siddha, Suresh B | 72486f1 | 2006-12-07 02:14:10 +0100 | [diff] [blame] | 198 | * @cpu - cpu->hotpluggable field set to 1 will generate a control file in |
| 199 | * sysfs for this CPU. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | * @num - CPU number to use when creating the device. |
| 201 | * |
| 202 | * Initialize and register the CPU device. |
| 203 | */ |
Randy Dunlap | 33b5f31 | 2008-02-06 01:36:28 -0800 | [diff] [blame] | 204 | int __cpuinit register_cpu(struct cpu *cpu, int num) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | { |
| 206 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | cpu->node_id = cpu_to_node(num); |
| 208 | cpu->sysdev.id = num; |
| 209 | cpu->sysdev.cls = &cpu_sysdev_class; |
| 210 | |
| 211 | error = sysdev_register(&cpu->sysdev); |
KAMEZAWA Hiroyuki | 76b67ed9 | 2006-06-27 02:53:41 -0700 | [diff] [blame] | 212 | |
Siddha, Suresh B | 72486f1 | 2006-12-07 02:14:10 +0100 | [diff] [blame] | 213 | if (!error && cpu->hotpluggable) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | register_cpu_control(cpu); |
Ashok Raj | ad74557 | 2005-10-30 14:59:49 -0800 | [diff] [blame] | 215 | if (!error) |
Mike Travis | e37d05d | 2008-05-01 04:35:16 -0700 | [diff] [blame] | 216 | per_cpu(cpu_sys_devices, num) = &cpu->sysdev; |
KAMEZAWA Hiroyuki | 76b67ed9 | 2006-06-27 02:53:41 -0700 | [diff] [blame] | 217 | if (!error) |
| 218 | register_cpu_under_node(num, cpu_to_node(num)); |
Vivek Goyal | 51be560 | 2006-01-09 20:51:42 -0800 | [diff] [blame] | 219 | |
| 220 | #ifdef CONFIG_KEXEC |
| 221 | if (!error) |
| 222 | error = sysdev_create_file(&cpu->sysdev, &attr_crash_notes); |
| 223 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | return error; |
| 225 | } |
| 226 | |
Andrew Morton | a29d642 | 2006-03-07 23:53:25 -0800 | [diff] [blame] | 227 | struct sys_device *get_cpu_sysdev(unsigned cpu) |
Ashok Raj | ad74557 | 2005-10-30 14:59:49 -0800 | [diff] [blame] | 228 | { |
Mike Travis | e37d05d | 2008-05-01 04:35:16 -0700 | [diff] [blame] | 229 | if (cpu < nr_cpu_ids && cpu_possible(cpu)) |
| 230 | return per_cpu(cpu_sys_devices, cpu); |
Ashok Raj | ad74557 | 2005-10-30 14:59:49 -0800 | [diff] [blame] | 231 | else |
| 232 | return NULL; |
| 233 | } |
| 234 | EXPORT_SYMBOL_GPL(get_cpu_sysdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | |
| 236 | int __init cpu_dev_init(void) |
| 237 | { |
Siddha, Suresh B | 5c45bf2 | 2006-06-27 02:54:42 -0700 | [diff] [blame] | 238 | int err; |
| 239 | |
| 240 | err = sysdev_class_register(&cpu_sysdev_class); |
Mike Travis | 9d1fe323 | 2008-04-08 11:43:04 -0700 | [diff] [blame] | 241 | if (!err) |
| 242 | err = cpu_states_init(); |
| 243 | |
Siddha, Suresh B | 5c45bf2 | 2006-06-27 02:54:42 -0700 | [diff] [blame] | 244 | #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) |
| 245 | if (!err) |
| 246 | err = sched_create_sysfs_power_savings_entries(&cpu_sysdev_class); |
| 247 | #endif |
| 248 | |
| 249 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | } |