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/
17 #include <linux/sysdev.h>
18 #include <linux/node.h>
19 #include <linux/compiler.h>
20 #include <linux/cpumask.h>
23 int node_id; /* The node which contains the CPU */
24 int hotpluggable; /* creates sysfs control file if hotpluggable */
25 struct sys_device sysdev;
28 extern int register_cpu(struct cpu *cpu, int num);
29 extern struct sys_device *get_cpu_sysdev(unsigned cpu);
31 extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr);
32 extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr);
34 extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs);
35 extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs);
37 extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
39 #ifdef CONFIG_HOTPLUG_CPU
40 extern void unregister_cpu(struct cpu *cpu);
41 extern ssize_t arch_cpu_probe(const char *, size_t);
42 extern ssize_t arch_cpu_release(const char *, size_t);
44 struct notifier_block;
47 * CPU notifier priorities.
51 * SCHED_ACTIVE marks a cpu which is coming up active during
52 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first
53 * notifier. CPUSET_ACTIVE adjusts cpuset according to
54 * cpu_active mask right after SCHED_ACTIVE. During
55 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are
56 * ordered in the similar way.
58 * This ordering guarantees consistent cpu_active mask and
59 * migration behavior to all cpu notifiers.
61 CPU_PRI_SCHED_ACTIVE = INT_MAX,
62 CPU_PRI_CPUSET_ACTIVE = INT_MAX - 1,
63 CPU_PRI_SCHED_INACTIVE = INT_MIN + 1,
64 CPU_PRI_CPUSET_INACTIVE = INT_MIN,
66 /* migration should happen before other stuff but after perf */
68 CPU_PRI_MIGRATION = 10,
69 /* bring up workqueues before normal notifiers and down after */
70 CPU_PRI_WORKQUEUE_UP = 5,
71 CPU_PRI_WORKQUEUE_DOWN = -5,
75 /* Need to know about CPUs going up/down? */
76 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
77 #define cpu_notifier(fn, pri) { \
78 static struct notifier_block fn##_nb __cpuinitdata = \
79 { .notifier_call = fn, .priority = pri }; \
80 register_cpu_notifier(&fn##_nb); \
82 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
83 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
84 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
85 #ifdef CONFIG_HOTPLUG_CPU
86 extern int register_cpu_notifier(struct notifier_block *nb);
87 extern void unregister_cpu_notifier(struct notifier_block *nb);
91 extern int register_cpu_notifier(struct notifier_block *nb);
93 static inline int register_cpu_notifier(struct notifier_block *nb)
99 static inline void unregister_cpu_notifier(struct notifier_block *nb)
104 int cpu_up(unsigned int cpu);
105 void notify_cpu_starting(unsigned int cpu);
106 extern void cpu_maps_update_begin(void);
107 extern void cpu_maps_update_done(void);
109 #else /* CONFIG_SMP */
111 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
113 static inline int register_cpu_notifier(struct notifier_block *nb)
118 static inline void unregister_cpu_notifier(struct notifier_block *nb)
122 static inline void cpu_maps_update_begin(void)
126 static inline void cpu_maps_update_done(void)
130 #endif /* CONFIG_SMP */
131 extern struct sysdev_class cpu_sysdev_class;
133 #ifdef CONFIG_HOTPLUG_CPU
134 /* Stop CPUs going up and down. */
136 extern void get_online_cpus(void);
137 extern void put_online_cpus(void);
138 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri)
139 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
140 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
141 int cpu_down(unsigned int cpu);
143 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
144 extern void cpu_hotplug_driver_lock(void);
145 extern void cpu_hotplug_driver_unlock(void);
147 static inline void cpu_hotplug_driver_lock(void)
151 static inline void cpu_hotplug_driver_unlock(void)
156 #else /* CONFIG_HOTPLUG_CPU */
158 #define get_online_cpus() do { } while (0)
159 #define put_online_cpus() do { } while (0)
160 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
161 /* These aren't inline functions due to a GCC bug. */
162 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; })
163 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); })
164 #endif /* CONFIG_HOTPLUG_CPU */
166 #ifdef CONFIG_PM_SLEEP_SMP
167 extern int suspend_cpu_hotplug;
169 extern int disable_nonboot_cpus(void);
170 extern void enable_nonboot_cpus(void);
171 #else /* !CONFIG_PM_SLEEP_SMP */
172 #define suspend_cpu_hotplug 0
174 static inline int disable_nonboot_cpus(void) { return 0; }
175 static inline void enable_nonboot_cpus(void) {}
176 #endif /* !CONFIG_PM_SLEEP_SMP */
181 void idle_notifier_register(struct notifier_block *n);
182 void idle_notifier_unregister(struct notifier_block *n);
183 void idle_notifier_call_chain(unsigned long val);
185 #endif /* _LINUX_CPU_H_ */