2 * include/linux/cpu.h - generic cpu definition
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.
8 * Basic handling of the devices is done in drivers/base/cpu.c
9 * and system devices are handled in drivers/base/sys.c.
11 * CPUs are exported via sysfs in the class/cpu/devices/
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
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>
30 int node_id; /* The node which contains the CPU */
31 int hotpluggable; /* creates sysfs control file if hotpluggable */
32 struct sys_device sysdev;
35 extern int register_cpu(struct cpu *cpu, int num);
36 extern struct sys_device *get_cpu_sysdev(unsigned cpu);
38 extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr);
39 extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr);
41 extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs);
42 extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs);
44 extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
46 #ifdef CONFIG_HOTPLUG_CPU
47 extern void unregister_cpu(struct cpu *cpu);
49 struct notifier_block;
52 /* Need to know about CPUs going up/down? */
53 #ifdef CONFIG_HOTPLUG_CPU
54 extern int register_cpu_notifier(struct notifier_block *nb);
55 extern void unregister_cpu_notifier(struct notifier_block *nb);
59 extern int register_cpu_notifier(struct notifier_block *nb);
61 static inline int register_cpu_notifier(struct notifier_block *nb)
67 static inline void unregister_cpu_notifier(struct notifier_block *nb)
72 int cpu_up(unsigned int cpu);
74 extern void cpu_hotplug_init(void);
78 static inline int register_cpu_notifier(struct notifier_block *nb)
83 static inline void unregister_cpu_notifier(struct notifier_block *nb)
87 static inline void cpu_hotplug_init(void)
91 #endif /* CONFIG_SMP */
92 extern struct sysdev_class cpu_sysdev_class;
93 extern void cpu_maps_update_begin(void);
94 extern void cpu_maps_update_done(void);
96 #ifdef CONFIG_HOTPLUG_CPU
97 /* Stop CPUs going up and down. */
99 static inline void cpuhotplug_mutex_lock(struct mutex *cpu_hp_mutex)
101 mutex_lock(cpu_hp_mutex);
104 static inline void cpuhotplug_mutex_unlock(struct mutex *cpu_hp_mutex)
106 mutex_unlock(cpu_hp_mutex);
109 extern void get_online_cpus(void);
110 extern 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); \
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);
120 #else /* CONFIG_HOTPLUG_CPU */
122 static inline void cpuhotplug_mutex_lock(struct mutex *cpu_hp_mutex)
124 static inline void cpuhotplug_mutex_unlock(struct mutex *cpu_hp_mutex)
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 */
135 #ifdef CONFIG_PM_SLEEP_SMP
136 extern int suspend_cpu_hotplug;
138 extern int disable_nonboot_cpus(void);
139 extern void enable_nonboot_cpus(void);
140 #else /* !CONFIG_PM_SLEEP_SMP */
141 #define suspend_cpu_hotplug 0
143 static inline int disable_nonboot_cpus(void) { return 0; }
144 static inline void enable_nonboot_cpus(void) {}
145 #endif /* !CONFIG_PM_SLEEP_SMP */
147 #endif /* _LINUX_CPU_H_ */