blob: 3fef7d67aedcdb301fcd00309824605315f37d85 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 *
Rolf Eike Beerd51fe1b2005-09-02 08:59:25 +020011 * CPUs are exported via sysfs in the class/cpu/devices/
Linus Torvalds1da177e2005-04-16 15:20:36 -070012 * 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#include <asm/semaphore.h>
27
28struct cpu {
29 int node_id; /* The node which contains the CPU */
30 int no_control; /* Should the sysfs control file be created? */
31 struct sys_device sysdev;
32};
33
KAMEZAWA Hiroyuki76b67ed2006-06-27 02:53:41 -070034extern int register_cpu(struct cpu *cpu, int num);
Andrew Mortona29d6422006-03-07 23:53:25 -080035extern struct sys_device *get_cpu_sysdev(unsigned cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#ifdef CONFIG_HOTPLUG_CPU
KAMEZAWA Hiroyuki76b67ed2006-06-27 02:53:41 -070037extern void unregister_cpu(struct cpu *cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#endif
39struct notifier_block;
40
41#ifdef CONFIG_SMP
42/* Need to know about CPUs going up/down? */
43extern int register_cpu_notifier(struct notifier_block *nb);
Chandra Seetharaman65edc682006-06-27 02:54:08 -070044#ifdef CONFIG_HOTPLUG_CPU
Linus Torvalds1da177e2005-04-16 15:20:36 -070045extern void unregister_cpu_notifier(struct notifier_block *nb);
Chandra Seetharaman65edc682006-06-27 02:54:08 -070046#else
47static inline void unregister_cpu_notifier(struct notifier_block *nb)
48{
49}
50#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
52int cpu_up(unsigned int cpu);
53
54#else
55
56static inline int register_cpu_notifier(struct notifier_block *nb)
57{
58 return 0;
59}
60static inline void unregister_cpu_notifier(struct notifier_block *nb)
61{
62}
63
64#endif /* CONFIG_SMP */
65extern struct sysdev_class cpu_sysdev_class;
66
67#ifdef CONFIG_HOTPLUG_CPU
68/* Stop CPUs going up and down. */
Ashok Raja9d9baa2005-11-28 13:43:46 -080069extern void lock_cpu_hotplug(void);
70extern void unlock_cpu_hotplug(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -070071#define hotcpu_notifier(fn, pri) { \
72 static struct notifier_block fn##_nb = \
73 { .notifier_call = fn, .priority = pri }; \
74 register_cpu_notifier(&fn##_nb); \
75}
Chandra Seetharaman39f48852006-06-27 02:54:10 -070076#define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
77#define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070078int cpu_down(unsigned int cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079#define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
80#else
81#define lock_cpu_hotplug() do { } while (0)
82#define unlock_cpu_hotplug() do { } while (0)
83#define lock_cpu_hotplug_interruptible() 0
Andrew Mortone2c27702006-07-01 04:36:30 -070084#define hotcpu_notifier(fn, pri) do { } while (0)
85#define register_hotcpu_notifier(nb) do { } while (0)
86#define unregister_hotcpu_notifier(nb) do { } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -070087
88/* CPUs don't go offline once they're online w/o CONFIG_HOTPLUG_CPU */
89static inline int cpu_is_offline(int cpu) { return 0; }
90#endif
91
Rafael J. Wysockie3920fb2006-09-25 23:32:48 -070092#ifdef CONFIG_SUSPEND_SMP
93extern int disable_nonboot_cpus(void);
94extern void enable_nonboot_cpus(void);
95#else
96static inline int disable_nonboot_cpus(void) { return 0; }
97static inline void enable_nonboot_cpus(void) {}
98#endif
99
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100#endif /* _LINUX_CPU_H_ */