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#include <asm/semaphore.h>
  27#include <linux/mutex.h>
  28
  29struct cpu {
  30        int node_id;            /* The node which contains the CPU */
  31        int hotpluggable;       /* creates sysfs control file if hotpluggable */
  32        struct sys_device sysdev;
  33};
  34
  35extern int register_cpu(struct cpu *cpu, int num);
  36extern struct sys_device *get_cpu_sysdev(unsigned cpu);
  37
  38extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr);
  39extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr);
  40
  41extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs);
  42extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs);
  43
  44extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
  45
  46#ifdef CONFIG_HOTPLUG_CPU
  47extern void unregister_cpu(struct cpu *cpu);
  48#endif
  49struct notifier_block;
  50
  51#ifdef CONFIG_SMP
  52/* Need to know about CPUs going up/down? */
  53#ifdef CONFIG_HOTPLUG_CPU
  54extern int register_cpu_notifier(struct notifier_block *nb);
  55extern void unregister_cpu_notifier(struct notifier_block *nb);
  56#else
  57
  58#ifndef MODULE
  59extern int register_cpu_notifier(struct notifier_block *nb);
  60#else
  61static inline int register_cpu_notifier(struct notifier_block *nb)
  62{
  63        return 0;
  64}
  65#endif
  66
  67static inline void unregister_cpu_notifier(struct notifier_block *nb)
  68{
  69}
  70#endif
  71
  72int cpu_up(unsigned int cpu);
  73
  74extern void cpu_hotplug_init(void);
  75
  76#else
  77
  78static inline int register_cpu_notifier(struct notifier_block *nb)
  79{
  80        return 0;
  81}
  82
  83static inline void unregister_cpu_notifier(struct notifier_block *nb)
  84{
  85}
  86
  87static inline void cpu_hotplug_init(void)
  88{
  89}
  90
  91#endif /* CONFIG_SMP */
  92extern struct sysdev_class cpu_sysdev_class;
  93extern void cpu_maps_update_begin(void);
  94extern void cpu_maps_update_done(void);
  95
  96#ifdef CONFIG_HOTPLUG_CPU
  97/* Stop CPUs going up and down. */
  98
  99static inline void cpuhotplug_mutex_lock(struct mutex *cpu_hp_mutex)
 100{
 101        mutex_lock(cpu_hp_mutex);
 102}
 103
 104static inline void cpuhotplug_mutex_unlock(struct mutex *cpu_hp_mutex)
 105{
 106        mutex_unlock(cpu_hp_mutex);
 107}
 108
 109extern void get_online_cpus(void);
 110extern void put_online_cpus(void);
 111#define hotcpu_notifier(fn, pri) {                              \
 112        static struct notifier_block fn##_nb =                  \
 113                { .notifier_call = fn, .priority = pri };       \
 114        register_cpu_notifier(&fn##_nb);                        \
 115}
 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#else           /* CONFIG_HOTPLUG_CPU */
 121
 122static inline void cpuhotplug_mutex_lock(struct mutex *cpu_hp_mutex)
 123{ }
 124static inline void cpuhotplug_mutex_unlock(struct mutex *cpu_hp_mutex)
 125{ }
 126
 127#define get_online_cpus()       do { } while (0)
 128#define put_online_cpus()       do { } while (0)
 129#define hotcpu_notifier(fn, pri)        do { (void)(fn); } while (0)
 130/* These aren't inline functions due to a GCC bug. */
 131#define register_hotcpu_notifier(nb)    ({ (void)(nb); 0; })
 132#define unregister_hotcpu_notifier(nb)  ({ (void)(nb); })
 133#endif          /* CONFIG_HOTPLUG_CPU */
 134
 135#ifdef CONFIG_PM_SLEEP_SMP
 136extern int suspend_cpu_hotplug;
 137
 138extern int disable_nonboot_cpus(void);
 139extern void enable_nonboot_cpus(void);
 140#else /* !CONFIG_PM_SLEEP_SMP */
 141#define suspend_cpu_hotplug     0
 142
 143static inline int disable_nonboot_cpus(void) { return 0; }
 144static inline void enable_nonboot_cpus(void) {}
 145#endif /* !CONFIG_PM_SLEEP_SMP */
 146
 147#endif /* _LINUX_CPU_H_ */
 148