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Diffstat (limited to 'include/linux/cpu.h')
-rw-r--r-- | include/linux/cpu.h | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/include/linux/cpu.h b/include/linux/cpu.h new file mode 100644 index 00000000000..fe0298e5dae --- /dev/null +++ b/include/linux/cpu.h @@ -0,0 +1,83 @@ +/* + * include/linux/cpu.h - generic cpu definition + * + * This is mainly for topological representation. We define the + * basic 'struct cpu' here, which can be embedded in per-arch + * definitions of processors. + * + * Basic handling of the devices is done in drivers/base/cpu.c + * and system devices are handled in drivers/base/sys.c. + * + * CPUs are exported via driverfs in the class/cpu/devices/ + * directory. + * + * Per-cpu interfaces can be implemented using a struct device_interface. + * See the following for how to do this: + * - drivers/base/intf.c + * - Documentation/driver-model/interface.txt + */ +#ifndef _LINUX_CPU_H_ +#define _LINUX_CPU_H_ + +#include <linux/sysdev.h> +#include <linux/node.h> +#include <linux/compiler.h> +#include <linux/cpumask.h> +#include <asm/semaphore.h> + +struct cpu { + int node_id; /* The node which contains the CPU */ + int no_control; /* Should the sysfs control file be created? */ + struct sys_device sysdev; +}; + +extern int register_cpu(struct cpu *, int, struct node *); +#ifdef CONFIG_HOTPLUG_CPU +extern void unregister_cpu(struct cpu *, struct node *); +#endif +struct notifier_block; + +#ifdef CONFIG_SMP +/* Need to know about CPUs going up/down? */ +extern int register_cpu_notifier(struct notifier_block *nb); +extern void unregister_cpu_notifier(struct notifier_block *nb); + +int cpu_up(unsigned int cpu); + +#else + +static inline int register_cpu_notifier(struct notifier_block *nb) +{ + return 0; +} +static inline void unregister_cpu_notifier(struct notifier_block *nb) +{ +} + +#endif /* CONFIG_SMP */ +extern struct sysdev_class cpu_sysdev_class; + +#ifdef CONFIG_HOTPLUG_CPU +/* Stop CPUs going up and down. */ +extern struct semaphore cpucontrol; +#define lock_cpu_hotplug() down(&cpucontrol) +#define unlock_cpu_hotplug() up(&cpucontrol) +#define lock_cpu_hotplug_interruptible() down_interruptible(&cpucontrol) +#define hotcpu_notifier(fn, pri) { \ + static struct notifier_block fn##_nb = \ + { .notifier_call = fn, .priority = pri }; \ + register_cpu_notifier(&fn##_nb); \ +} +int cpu_down(unsigned int cpu); +#define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) +#else +#define lock_cpu_hotplug() do { } while (0) +#define unlock_cpu_hotplug() do { } while (0) +#define lock_cpu_hotplug_interruptible() 0 +#define hotcpu_notifier(fn, pri) + +/* CPUs don't go offline once they're online w/o CONFIG_HOTPLUG_CPU */ +static inline int cpu_is_offline(int cpu) { return 0; } +#endif + +#endif /* _LINUX_CPU_H_ */ |