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
10 * CPUs are exported via sysfs in the devices/system/cpu
16 #include <linux/node.h>
17 #include <linux/compiler.h>
18 #include <linux/cpumask.h>
23 int node_id
; /* The node which contains the CPU */
24 int hotpluggable
; /* creates sysfs control file if hotpluggable */
28 extern int register_cpu(struct cpu
*cpu
, int num
);
29 extern struct device
*get_cpu_device(unsigned cpu
);
30 extern bool cpu_is_hotpluggable(unsigned cpu
);
32 extern int cpu_add_dev_attr(struct device_attribute
*attr
);
33 extern void cpu_remove_dev_attr(struct device_attribute
*attr
);
35 extern int cpu_add_dev_attr_group(struct attribute_group
*attrs
);
36 extern void cpu_remove_dev_attr_group(struct attribute_group
*attrs
);
38 #ifdef CONFIG_HOTPLUG_CPU
39 extern void unregister_cpu(struct cpu
*cpu
);
40 extern ssize_t
arch_cpu_probe(const char *, size_t);
41 extern ssize_t
arch_cpu_release(const char *, size_t);
43 struct notifier_block
;
45 #ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
46 extern int arch_cpu_uevent(struct device
*dev
, struct kobj_uevent_env
*env
);
47 extern ssize_t
arch_print_cpu_modalias(struct device
*dev
,
48 struct device_attribute
*attr
,
53 * CPU notifier priorities.
57 * SCHED_ACTIVE marks a cpu which is coming up active during
58 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first
59 * notifier. CPUSET_ACTIVE adjusts cpuset according to
60 * cpu_active mask right after SCHED_ACTIVE. During
61 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are
62 * ordered in the similar way.
64 * This ordering guarantees consistent cpu_active mask and
65 * migration behavior to all cpu notifiers.
67 CPU_PRI_SCHED_ACTIVE
= INT_MAX
,
68 CPU_PRI_CPUSET_ACTIVE
= INT_MAX
- 1,
69 CPU_PRI_SCHED_INACTIVE
= INT_MIN
+ 1,
70 CPU_PRI_CPUSET_INACTIVE
= INT_MIN
,
72 /* migration should happen before other stuff but after perf */
74 CPU_PRI_MIGRATION
= 10,
75 /* bring up workqueues before normal notifiers and down after */
76 CPU_PRI_WORKQUEUE_UP
= 5,
77 CPU_PRI_WORKQUEUE_DOWN
= -5,
80 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */
81 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */
82 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */
83 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */
84 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */
85 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */
86 #define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task,
87 * not handling interrupts, soon dead.
88 * Called on the dying cpu, interrupts
89 * are already disabled. Must not
90 * sleep, must not fail */
91 #define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug
93 #define CPU_STARTING 0x000A /* CPU (unsigned)v soon running.
94 * Called on the new cpu, just before
95 * enabling interrupts. Must not sleep,
98 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
99 * operation in progress
101 #define CPU_TASKS_FROZEN 0x0010
103 #define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN)
104 #define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN)
105 #define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
106 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
107 #define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
108 #define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN)
109 #define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN)
110 #define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN)
114 /* Need to know about CPUs going up/down? */
115 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
116 #define cpu_notifier(fn, pri) { \
117 static struct notifier_block fn##_nb __cpuinitdata = \
118 { .notifier_call = fn, .priority = pri }; \
119 register_cpu_notifier(&fn##_nb); \
121 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
122 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
123 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
124 #ifdef CONFIG_HOTPLUG_CPU
125 extern int register_cpu_notifier(struct notifier_block
*nb
);
126 extern void unregister_cpu_notifier(struct notifier_block
*nb
);
130 extern int register_cpu_notifier(struct notifier_block
*nb
);
132 static inline int register_cpu_notifier(struct notifier_block
*nb
)
138 static inline void unregister_cpu_notifier(struct notifier_block
*nb
)
143 int cpu_up(unsigned int cpu
);
144 void notify_cpu_starting(unsigned int cpu
);
145 extern void cpu_maps_update_begin(void);
146 extern void cpu_maps_update_done(void);
148 #else /* CONFIG_SMP */
150 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
152 static inline int register_cpu_notifier(struct notifier_block
*nb
)
157 static inline void unregister_cpu_notifier(struct notifier_block
*nb
)
161 static inline void cpu_maps_update_begin(void)
165 static inline void cpu_maps_update_done(void)
169 #endif /* CONFIG_SMP */
170 extern struct bus_type cpu_subsys
;
172 #ifdef CONFIG_HOTPLUG_CPU
173 /* Stop CPUs going up and down. */
175 extern void get_online_cpus(void);
176 extern void put_online_cpus(void);
177 extern void cpu_hotplug_disable(void);
178 extern void cpu_hotplug_enable(void);
179 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri)
180 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
181 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
182 void clear_tasks_mm_cpumask(int cpu
);
183 int cpu_down(unsigned int cpu
);
185 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
186 extern void cpu_hotplug_driver_lock(void);
187 extern void cpu_hotplug_driver_unlock(void);
189 static inline void cpu_hotplug_driver_lock(void)
193 static inline void cpu_hotplug_driver_unlock(void)
198 #else /* CONFIG_HOTPLUG_CPU */
200 #define get_online_cpus() do { } while (0)
201 #define put_online_cpus() do { } while (0)
202 #define cpu_hotplug_disable() do { } while (0)
203 #define cpu_hotplug_enable() do { } while (0)
204 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
205 /* These aren't inline functions due to a GCC bug. */
206 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; })
207 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); })
208 #endif /* CONFIG_HOTPLUG_CPU */
210 #ifdef CONFIG_PM_SLEEP_SMP
211 extern int disable_nonboot_cpus(void);
212 extern void enable_nonboot_cpus(void);
213 #else /* !CONFIG_PM_SLEEP_SMP */
214 static inline int disable_nonboot_cpus(void) { return 0; }
215 static inline void enable_nonboot_cpus(void) {}
216 #endif /* !CONFIG_PM_SLEEP_SMP */
223 void cpu_startup_entry(enum cpuhp_state state
);
226 void cpu_idle_poll_ctrl(bool enable
);
228 void arch_cpu_idle(void);
229 void arch_cpu_idle_prepare(void);
230 void arch_cpu_idle_enter(void);
231 void arch_cpu_idle_exit(void);
232 void arch_cpu_idle_dead(void);
234 #endif /* _LINUX_CPU_H_ */