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_maps_update_begin(void); 73 extern void cpu_maps_update_done(void); 74 75 #else /* CONFIG_SMP */ 76 77 static inline int register_cpu_notifier(struct notifier_block *nb) 78 { 79 return 0; 80 } 81 82 static inline void unregister_cpu_notifier(struct notifier_block *nb) 83 { 84 } 85 86 static inline void cpu_maps_update_begin(void) 87 { 88 } 89 90 static inline void cpu_maps_update_done(void) 91 { 92 } 93 94 #endif /* CONFIG_SMP */ 95 extern struct sysdev_class cpu_sysdev_class; 96 97 #ifdef CONFIG_HOTPLUG_CPU 98 /* Stop CPUs going up and down. */ 99 100 extern void get_online_cpus(void); 101 extern 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) 109 int 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 122 extern int suspend_cpu_hotplug; 123 124 extern int disable_nonboot_cpus(void); 125 extern void enable_nonboot_cpus(void); 126 #else /* !CONFIG_PM_SLEEP_SMP */ 127 #define suspend_cpu_hotplug 0 128 129 static inline int disable_nonboot_cpus(void) { return 0; } 130 static inline void enable_nonboot_cpus(void) {} 131 #endif /* !CONFIG_PM_SLEEP_SMP */ 132 133 #endif /* _LINUX_CPU_H_ */ 134