LXR linux/include/linux/cpu.h

   1/*
   2 * include/linux/cpu.h - generic cpu definition
   3 *
   4 * This is mainly for topological representation. We define the 
   5 * basic 'struct cpu' here, which can be embedded in per-arch 
   6 * definitions of processors.
   7 *
   8 * Basic handling of the devices is done in drivers/base/cpu.c
   9 * and system devices are handled in drivers/base/sys.c. 
  10 *
  11 * CPUs are exported via sysfs in the class/cpu/devices/
  12 * directory. 
  13 *
  14 * Per-cpu interfaces can be implemented using a struct device_interface. 
  15 * See the following for how to do this: 
  16 * - drivers/base/intf.c 
  17 * - Documentation/driver-model/interface.txt
  18 */
  19#ifndef _LINUX_CPU_H_
  20#define _LINUX_CPU_H_
  21
  22#include <linux/sysdev.h>
  23#include <linux/node.h>
  24#include <linux/compiler.h>
  25#include <linux/cpumask.h>
  26
  27struct cpu {
  28        int node_id;            /* The node which contains the CPU */
  29        int hotpluggable;       /* creates sysfs control file if hotpluggable */
  30        struct sys_device sysdev;
  31};
  32
  33extern int register_cpu(struct cpu *cpu, int num);
  34extern struct sys_device *get_cpu_sysdev(unsigned cpu);
  35
  36extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr);
  37extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr);
  38
  39extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs);
  40extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs);
  41
  42extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
  43
  44#ifdef CONFIG_HOTPLUG_CPU
  45extern void unregister_cpu(struct cpu *cpu);
  46extern ssize_t arch_cpu_probe(const char *, size_t);
  47extern ssize_t arch_cpu_release(const char *, size_t);
  48#endif
  49struct notifier_block;
  50
  51#ifdef CONFIG_SMP
  52/* Need to know about CPUs going up/down? */
  53#if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
  54#define cpu_notifier(fn, pri) {                                 \
  55        static struct notifier_block fn##_nb __cpuinitdata =    \
  56                { .notifier_call = fn, .priority = pri };       \
  57        register_cpu_notifier(&fn##_nb);                        \
  58}
  59#else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
  60#define cpu_notifier(fn, pri)   do { (void)(fn); } while (0)
  61#endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
  62#ifdef CONFIG_HOTPLUG_CPU
  63extern int register_cpu_notifier(struct notifier_block *nb);
  64extern void unregister_cpu_notifier(struct notifier_block *nb);
  65#else
  66
  67#ifndef MODULE
  68extern int register_cpu_notifier(struct notifier_block *nb);
  69#else
  70static inline int register_cpu_notifier(struct notifier_block *nb)
  71{
  72        return 0;
  73}
  74#endif
  75
  76static inline void unregister_cpu_notifier(struct notifier_block *nb)
  77{
  78}
  79#endif
  80
  81int cpu_up(unsigned int cpu);
  82void notify_cpu_starting(unsigned int cpu);
  83extern void cpu_maps_update_begin(void);
  84extern void cpu_maps_update_done(void);
  85
  86#else   /* CONFIG_SMP */
  87
  88#define cpu_notifier(fn, pri)   do { (void)(fn); } while (0)
  89
  90static inline int register_cpu_notifier(struct notifier_block *nb)
  91{
  92        return 0;
  93}
  94
  95static inline void unregister_cpu_notifier(struct notifier_block *nb)
  96{
  97}
  98
  99static inline void cpu_maps_update_begin(void)
 100{
 101}
 102
 103static inline void cpu_maps_update_done(void)
 104{
 105}
 106
 107#endif /* CONFIG_SMP */
 108extern struct sysdev_class cpu_sysdev_class;
 109
 110#ifdef CONFIG_HOTPLUG_CPU
 111/* Stop CPUs going up and down. */
 112
 113extern void get_online_cpus(void);
 114extern void put_online_cpus(void);
 115#define hotcpu_notifier(fn, pri)        cpu_notifier(fn, pri)
 116#define register_hotcpu_notifier(nb)    register_cpu_notifier(nb)
 117#define unregister_hotcpu_notifier(nb)  unregister_cpu_notifier(nb)
 118int cpu_down(unsigned int cpu);
 119
 120#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
 121extern void cpu_hotplug_driver_lock(void);
 122extern void cpu_hotplug_driver_unlock(void);
 123#else
 124static inline void cpu_hotplug_driver_lock(void)
 125{
 126}
 127
 128static inline void cpu_hotplug_driver_unlock(void)
 129{
 130}
 131#endif
 132
 133#else           /* CONFIG_HOTPLUG_CPU */
 134
 135#define get_online_cpus()       do { } while (0)
 136#define put_online_cpus()       do { } while (0)
 137#define hotcpu_notifier(fn, pri)        do { (void)(fn); } while (0)
 138/* These aren't inline functions due to a GCC bug. */
 139#define register_hotcpu_notifier(nb)    ({ (void)(nb); 0; })
 140#define unregister_hotcpu_notifier(nb)  ({ (void)(nb); })
 141#endif          /* CONFIG_HOTPLUG_CPU */
 142
 143#ifdef CONFIG_PM_SLEEP_SMP
 144extern int suspend_cpu_hotplug;
 145
 146extern int disable_nonboot_cpus(void);
 147extern void enable_nonboot_cpus(void);
 148#else /* !CONFIG_PM_SLEEP_SMP */
 149#define suspend_cpu_hotplug     0
 150
 151static inline int disable_nonboot_cpus(void) { return 0; }
 152static inline void enable_nonboot_cpus(void) {}
 153#endif /* !CONFIG_PM_SLEEP_SMP */
 154
 155#endif /* _LINUX_CPU_H_ */
 156