cpu.c revision ad74557a49d1dea428fb0ad60e75a5aa37610e1d
11da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 21da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * drivers/base/cpu.c - basic CPU class support 31da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 41da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 51da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/sysdev.h> 61da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/module.h> 71da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/init.h> 81da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/cpu.h> 91da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/topology.h> 101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/device.h> 111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 12a1bdc7aad8b557176ccecff1da137ebe3090871eBen Dooks#include "base.h" 131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstruct sysdev_class cpu_sysdev_class = { 151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds set_kset_name("cpu"), 161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds}; 171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus TorvaldsEXPORT_SYMBOL(cpu_sysdev_class); 181da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 19ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Rajstatic struct sys_device *cpu_sys_devices[NR_CPUS]; 20ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj 211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#ifdef CONFIG_HOTPLUG_CPU 2252a119feaad92d44a0e97d01b22afbcbaf3fc079Ashok Rajint __attribute__((weak)) smp_prepare_cpu (int cpu) 2352a119feaad92d44a0e97d01b22afbcbaf3fc079Ashok Raj{ 2452a119feaad92d44a0e97d01b22afbcbaf3fc079Ashok Raj return 0; 2552a119feaad92d44a0e97d01b22afbcbaf3fc079Ashok Raj} 26e1367daf3eed5cd619ee88c9907e1e6ddaa58406Li Shaohua 271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic ssize_t show_online(struct sys_device *dev, char *buf) 281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct cpu *cpu = container_of(dev, struct cpu, sysdev); 301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return sprintf(buf, "%u\n", !!cpu_online(cpu->sysdev.id)); 321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic ssize_t store_online(struct sys_device *dev, const char *buf, 351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds size_t count) 361da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 371da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds struct cpu *cpu = container_of(dev, struct cpu, sysdev); 381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ssize_t ret; 391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds switch (buf[0]) { 411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds case '0': 421da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ret = cpu_down(cpu->sysdev.id); 431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!ret) 441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds kobject_hotplug(&dev->kobj, KOBJ_OFFLINE); 451da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; 461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds case '1': 47e1367daf3eed5cd619ee88c9907e1e6ddaa58406Li Shaohua ret = smp_prepare_cpu(cpu->sysdev.id); 4852a119feaad92d44a0e97d01b22afbcbaf3fc079Ashok Raj if (!ret) 49e1367daf3eed5cd619ee88c9907e1e6ddaa58406Li Shaohua ret = cpu_up(cpu->sysdev.id); 50fb69c3907ead36b9e9f41ea6f0d0e0ae10a38a47Nathan Lynch if (!ret) 51fb69c3907ead36b9e9f41ea6f0d0e0ae10a38a47Nathan Lynch kobject_hotplug(&dev->kobj, KOBJ_ONLINE); 521da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; 531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds default: 541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ret = -EINVAL; 551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 571da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (ret >= 0) 581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ret = count; 591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return ret; 601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 611da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic SYSDEV_ATTR(online, 0600, show_online, store_online); 621da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 631da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic void __devinit register_cpu_control(struct cpu *cpu) 641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 651da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds sysdev_create_file(&cpu->sysdev, &attr_online); 661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 671da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsvoid unregister_cpu(struct cpu *cpu, struct node *root) 681da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 69ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj int logical_cpu = cpu->sysdev.id; 701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 711da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (root) 721da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds sysfs_remove_link(&root->sysdev.kobj, 731da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds kobject_name(&cpu->sysdev.kobj)); 741da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds sysdev_remove_file(&cpu->sysdev, &attr_online); 751da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds sysdev_unregister(&cpu->sysdev); 77ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj cpu_sys_devices[logical_cpu] = NULL; 781da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return; 791da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#else /* ... !CONFIG_HOTPLUG_CPU */ 811da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic inline void register_cpu_control(struct cpu *cpu) 821da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 831da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 841da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#endif /* CONFIG_HOTPLUG_CPU */ 851da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 871da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * register_cpu - Setup a driverfs device for a CPU. 881da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * @cpu - Callers can set the cpu->no_control field to 1, to indicate not to 891da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * generate a control file in sysfs for this CPU. 901da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * @num - CPU number to use when creating the device. 911da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 921da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Initialize and register the CPU device. 931da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 941da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsint __devinit register_cpu(struct cpu *cpu, int num, struct node *root) 951da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 961da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int error; 971da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 981da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds cpu->node_id = cpu_to_node(num); 991da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds cpu->sysdev.id = num; 1001da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds cpu->sysdev.cls = &cpu_sysdev_class; 1011da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1021da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds error = sysdev_register(&cpu->sysdev); 1031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!error && root) 1041da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds error = sysfs_create_link(&root->sysdev.kobj, 1051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds &cpu->sysdev.kobj, 1061da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds kobject_name(&cpu->sysdev.kobj)); 1071da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!error && !cpu->no_control) 1081da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds register_cpu_control(cpu); 109ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj if (!error) 110ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj cpu_sys_devices[num] = &cpu->sysdev; 1111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return error; 1121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 114ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Rajstruct sys_device *get_cpu_sysdev(int cpu) 115ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj{ 116ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj if (cpu < NR_CPUS) 117ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj return cpu_sys_devices[cpu]; 118ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj else 119ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj return NULL; 120ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj} 121ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok RajEXPORT_SYMBOL_GPL(get_cpu_sysdev); 1221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 1231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsint __init cpu_dev_init(void) 1241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 1251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return sysdev_class_register(&cpu_sysdev_class); 1261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 127