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 27 struct 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 33 extern int register_cpu(struct cpu *cpu, int num); 34 extern struct sys_device *get_cpu_sysdev(unsigned cpu); 35 36 extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr); 37 extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr); 38 39 extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs); 40 extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs); 41 42 extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls); 43 44 #ifdef CONFIG_HOTPLUG_CPU 45 extern void unregister_cpu(struct cpu *cpu); 46 extern ssize_t arch_cpu_probe(const char *, size_t); 47 extern ssize_t arch_cpu_release(const char *, size_t); 48 #endif 49 struct 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 63 extern int register_cpu_notifier(struct notifier_block *nb); 64 extern void unregister_cpu_notifier(struct notifier_block *nb); 65 #else 66 67 #ifndef MODULE 68 extern int register_cpu_notifier(struct notifier_block *nb); 69 #else 70 static inline int register_cpu_notifier(struct notifier_block *nb) 71 { 72 return 0; 73 } 74 #endif 75 76 static inline void unregister_cpu_notifier(struct notifier_block *nb) 77 { 78 } 79 #endif 80 81 int cpu_up(unsigned int cpu); 82 void notify_cpu_starting(unsigned int cpu); 83 extern void cpu_maps_update_begin(void); 84 extern void cpu_maps_update_done(void); 85 86 #else /* CONFIG_SMP */ 87 88 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 89 90 static inline int register_cpu_notifier(struct notifier_block *nb) 91 { 92 return 0; 93 } 94 95 static inline void unregister_cpu_notifier(struct notifier_block *nb) 96 { 97 } 98 99 static inline void cpu_maps_update_begin(void) 100 { 101 } 102 103 static inline void cpu_maps_update_done(void) 104 { 105 } 106 107 #endif /* CONFIG_SMP */ 108 extern struct sysdev_class cpu_sysdev_class; 109 110 #ifdef CONFIG_HOTPLUG_CPU 111 /* Stop CPUs going up and down. */ 112 113 extern void get_online_cpus(void); 114 extern 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) 118 int cpu_down(unsigned int cpu); 119 120 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE 121 extern void cpu_hotplug_driver_lock(void); 122 extern void cpu_hotplug_driver_unlock(void); 123 #else 124 static inline void cpu_hotplug_driver_lock(void) 125 { 126 } 127 128 static 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 144 extern int suspend_cpu_hotplug; 145 146 extern int disable_nonboot_cpus(void); 147 extern void enable_nonboot_cpus(void); 148 #else /* !CONFIG_PM_SLEEP_SMP */ 149 #define suspend_cpu_hotplug 0 150 151 static inline int disable_nonboot_cpus(void) { return 0; } 152 static inline void enable_nonboot_cpus(void) {} 153 #endif /* !CONFIG_PM_SLEEP_SMP */ 154 155 #endif /* _LINUX_CPU_H_ */ 156