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 #endif 47 struct notifier_block; 48 49 #ifdef CONFIG_SMP 50 /* Need to know about CPUs going up/down? */ 51 #ifdef CONFIG_HOTPLUG_CPU 52 extern int register_cpu_notifier(struct notifier_block *nb); 53 extern void unregister_cpu_notifier(struct notifier_block *nb); 54 #else 55 56 #ifndef MODULE 57 extern int register_cpu_notifier(struct notifier_block *nb); 58 #else 59 static inline int register_cpu_notifier(struct notifier_block *nb) 60 { 61 return 0; 62 } 63 #endif 64 65 static inline void unregister_cpu_notifier(struct notifier_block *nb) 66 { 67 } 68 #endif 69 70 int cpu_up(unsigned int cpu); 71 void notify_cpu_starting(unsigned int cpu); 72 extern void cpu_hotplug_init(void); 73 extern void cpu_maps_update_begin(void); 74 extern void cpu_maps_update_done(void); 75 76 #else /* CONFIG_SMP */ 77 78 static inline int register_cpu_notifier(struct notifier_block *nb) 79 { 80 return 0; 81 } 82 83 static inline void unregister_cpu_notifier(struct notifier_block *nb) 84 { 85 } 86 87 static inline void cpu_hotplug_init(void) 88 { 89 } 90 91 static inline void cpu_maps_update_begin(void) 92 { 93 } 94 95 static inline void cpu_maps_update_done(void) 96 { 97 } 98 99 #endif /* CONFIG_SMP */ 100 extern struct sysdev_class cpu_sysdev_class; 101 102 #ifdef CONFIG_HOTPLUG_CPU 103 /* Stop CPUs going up and down. */ 104 105 extern void get_online_cpus(void); 106 extern void put_online_cpus(void); 107 #define hotcpu_notifier(fn, pri) { \ 108 static struct notifier_block fn##_nb __cpuinitdata = \ 109 { .notifier_call = fn, .priority = pri }; \ 110 register_cpu_notifier(&fn##_nb); \ 111 } 112 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) 113 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) 114 int cpu_down(unsigned int cpu); 115 116 #else /* CONFIG_HOTPLUG_CPU */ 117 118 #define get_online_cpus() do { } while (0) 119 #define put_online_cpus() do { } while (0) 120 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 121 /* These aren't inline functions due to a GCC bug. */ 122 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 123 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 124 #endif /* CONFIG_HOTPLUG_CPU */ 125 126 #ifdef CONFIG_PM_SLEEP_SMP 127 extern int suspend_cpu_hotplug; 128 129 extern int disable_nonboot_cpus(void); 130 extern void enable_nonboot_cpus(void); 131 #else /* !CONFIG_PM_SLEEP_SMP */ 132 #define suspend_cpu_hotplug 0 133 134 static inline int disable_nonboot_cpus(void) { return 0; } 135 static inline void enable_nonboot_cpus(void) {} 136 #endif /* !CONFIG_PM_SLEEP_SMP */ 137 138 #endif /* _LINUX_CPU_H_ */ 139