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);
  46#endif
  47struct notifier_block;
  48
  49#ifdef CONFIG_SMP
  50/* Need to know about CPUs going up/down? */
  51#ifdef CONFIG_HOTPLUG_CPU
  52extern int register_cpu_notifier(struct notifier_block *nb);
  53extern void unregister_cpu_notifier(struct notifier_block *nb);
  54#else
  55
  56#ifndef MODULE
  57extern int register_cpu_notifier(struct notifier_block *nb);
  58#else
  59static inline int register_cpu_notifier(struct notifier_block *nb)
  60{
  61        return 0;
  62}
  63#endif
  64
  65static inline void unregister_cpu_notifier(struct notifier_block *nb)
  66{
  67}
  68#endif
  69
  70int cpu_up(unsigned int cpu);
  71void notify_cpu_starting(unsigned int cpu);
  72extern void cpu_maps_update_begin(void);
  73extern void cpu_maps_update_done(void);
  74
  75#else   /* CONFIG_SMP */
  76
  77static inline int register_cpu_notifier(struct notifier_block *nb)
  78{
  79        return 0;
  80}
  81
  82static inline void unregister_cpu_notifier(struct notifier_block *nb)
  83{
  84}
  85
  86static inline void cpu_maps_update_begin(void)
  87{
  88}
  89
  90static inline void cpu_maps_update_done(void)
  91{
  92}
  93
  94#endif /* CONFIG_SMP */
  95extern struct sysdev_class cpu_sysdev_class;
  96
  97#ifdef CONFIG_HOTPLUG_CPU
  98/* Stop CPUs going up and down. */
  99
 100extern void get_online_cpus(void);
 101extern void put_online_cpus(void);
 102#define hotcpu_notifier(fn, pri) {                              \
 103        static struct notifier_block fn##_nb __cpuinitdata =    \
 104                { .notifier_call = fn, .priority = pri };       \
 105        register_cpu_notifier(&fn##_nb);                        \
 106}
 107#define register_hotcpu_notifier(nb)    register_cpu_notifier(nb)
 108#define unregister_hotcpu_notifier(nb)  unregister_cpu_notifier(nb)
 109int cpu_down(unsigned int cpu);
 110
 111#else           /* CONFIG_HOTPLUG_CPU */
 112
 113#define get_online_cpus()       do { } while (0)
 114#define put_online_cpus()       do { } while (0)
 115#define hotcpu_notifier(fn, pri)        do { (void)(fn); } while (0)
 116/* These aren't inline functions due to a GCC bug. */
 117#define register_hotcpu_notifier(nb)    ({ (void)(nb); 0; })
 118#define unregister_hotcpu_notifier(nb)  ({ (void)(nb); })
 119#endif          /* CONFIG_HOTPLUG_CPU */
 120
 121#ifdef CONFIG_PM_SLEEP_SMP
 122extern int suspend_cpu_hotplug;
 123
 124extern int disable_nonboot_cpus(void);
 125extern void enable_nonboot_cpus(void);
 126#else /* !CONFIG_PM_SLEEP_SMP */
 127#define suspend_cpu_hotplug     0
 128
 129static inline int disable_nonboot_cpus(void) { return 0; }
 130static inline void enable_nonboot_cpus(void) {}
 131#endif /* !CONFIG_PM_SLEEP_SMP */
 132
 133#endif /* _LINUX_CPU_H_ */
 134