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>
22 struct attribute_group;
25 int node_id; /* The node which contains the CPU */
26 int hotpluggable; /* creates sysfs control file if hotpluggable */
30 extern int register_cpu(struct cpu *cpu, int num);
31 extern struct device *get_cpu_device(unsigned cpu);
32 extern bool cpu_is_hotpluggable(unsigned cpu);
33 extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id);
34 extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
35 int cpu, unsigned int *thread);
37 extern int cpu_add_dev_attr(struct device_attribute *attr);
38 extern void cpu_remove_dev_attr(struct device_attribute *attr);
40 extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
41 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
43 extern struct device *cpu_device_create(struct device *parent, void *drvdata,
44 const struct attribute_group **groups,
45 const char *fmt, ...);
46 #ifdef CONFIG_HOTPLUG_CPU
47 extern void unregister_cpu(struct cpu *cpu);
48 extern ssize_t arch_cpu_probe(const char *, size_t);
49 extern ssize_t arch_cpu_release(const char *, size_t);
51 struct notifier_block;
54 * CPU notifier priorities.
58 * SCHED_ACTIVE marks a cpu which is coming up active during
59 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first
60 * notifier. CPUSET_ACTIVE adjusts cpuset according to
61 * cpu_active mask right after SCHED_ACTIVE. During
62 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are
63 * ordered in the similar way.
65 * This ordering guarantees consistent cpu_active mask and
66 * migration behavior to all cpu notifiers.
68 CPU_PRI_SCHED_ACTIVE = INT_MAX,
69 CPU_PRI_CPUSET_ACTIVE = INT_MAX - 1,
70 CPU_PRI_SCHED_INACTIVE = INT_MIN + 1,
71 CPU_PRI_CPUSET_INACTIVE = INT_MIN,
73 /* migration should happen before other stuff but after perf */
75 CPU_PRI_MIGRATION = 10,
76 /* bring up workqueues before normal notifiers and down after */
77 CPU_PRI_WORKQUEUE_UP = 5,
78 CPU_PRI_WORKQUEUE_DOWN = -5,
81 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */
82 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */
83 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */
84 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */
85 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */
86 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */
87 #define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task,
88 * not handling interrupts, soon dead.
89 * Called on the dying cpu, interrupts
90 * are already disabled. Must not
91 * sleep, must not fail */
92 #define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug
94 #define CPU_STARTING 0x000A /* CPU (unsigned)v soon running.
95 * Called on the new cpu, just before
96 * enabling interrupts. Must not sleep,
98 #define CPU_BROKEN 0x000C /* CPU (unsigned)v did not die properly,
99 * perhaps due to preemption. */
101 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
102 * operation in progress
104 #define CPU_TASKS_FROZEN 0x0010
106 #define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN)
107 #define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN)
108 #define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
109 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
110 #define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
111 #define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN)
112 #define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN)
113 #define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN)
117 /* Need to know about CPUs going up/down? */
118 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
119 #define cpu_notifier(fn, pri) { \
120 static struct notifier_block fn##_nb = \
121 { .notifier_call = fn, .priority = pri }; \
122 register_cpu_notifier(&fn##_nb); \
125 #define __cpu_notifier(fn, pri) { \
126 static struct notifier_block fn##_nb = \
127 { .notifier_call = fn, .priority = pri }; \
128 __register_cpu_notifier(&fn##_nb); \
130 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
131 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
132 #define __cpu_notifier(fn, pri) do { (void)(fn); } while (0)
133 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
135 #ifdef CONFIG_HOTPLUG_CPU
136 extern int register_cpu_notifier(struct notifier_block *nb);
137 extern int __register_cpu_notifier(struct notifier_block *nb);
138 extern void unregister_cpu_notifier(struct notifier_block *nb);
139 extern void __unregister_cpu_notifier(struct notifier_block *nb);
143 extern int register_cpu_notifier(struct notifier_block *nb);
144 extern int __register_cpu_notifier(struct notifier_block *nb);
146 static inline int register_cpu_notifier(struct notifier_block *nb)
151 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 __unregister_cpu_notifier(struct notifier_block *nb)
166 int cpu_up(unsigned int cpu);
167 void notify_cpu_starting(unsigned int cpu);
168 extern void cpu_maps_update_begin(void);
169 extern void cpu_maps_update_done(void);
171 #define cpu_notifier_register_begin cpu_maps_update_begin
172 #define cpu_notifier_register_done cpu_maps_update_done
174 #else /* CONFIG_SMP */
176 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
177 #define __cpu_notifier(fn, pri) do { (void)(fn); } while (0)
179 static inline int register_cpu_notifier(struct notifier_block *nb)
184 static inline int __register_cpu_notifier(struct notifier_block *nb)
189 static inline void unregister_cpu_notifier(struct notifier_block *nb)
193 static inline void __unregister_cpu_notifier(struct notifier_block *nb)
197 static inline void cpu_maps_update_begin(void)
201 static inline void cpu_maps_update_done(void)
205 static inline void cpu_notifier_register_begin(void)
209 static inline void cpu_notifier_register_done(void)
213 #endif /* CONFIG_SMP */
214 extern struct bus_type cpu_subsys;
216 #ifdef CONFIG_HOTPLUG_CPU
217 /* Stop CPUs going up and down. */
219 extern void cpu_hotplug_begin(void);
220 extern void cpu_hotplug_done(void);
221 extern void get_online_cpus(void);
222 extern bool try_get_online_cpus(void);
223 extern void put_online_cpus(void);
224 extern void cpu_hotplug_disable(void);
225 extern void cpu_hotplug_enable(void);
226 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri)
227 #define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri)
228 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
229 #define __register_hotcpu_notifier(nb) __register_cpu_notifier(nb)
230 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
231 #define __unregister_hotcpu_notifier(nb) __unregister_cpu_notifier(nb)
232 void clear_tasks_mm_cpumask(int cpu);
233 int cpu_down(unsigned int cpu);
235 #else /* CONFIG_HOTPLUG_CPU */
237 static inline void cpu_hotplug_begin(void) {}
238 static inline void cpu_hotplug_done(void) {}
239 #define get_online_cpus() do { } while (0)
240 #define try_get_online_cpus() true
241 #define put_online_cpus() do { } while (0)
242 #define cpu_hotplug_disable() do { } while (0)
243 #define cpu_hotplug_enable() do { } while (0)
244 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
245 #define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
246 /* These aren't inline functions due to a GCC bug. */
247 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; })
248 #define __register_hotcpu_notifier(nb) ({ (void)(nb); 0; })
249 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); })
250 #define __unregister_hotcpu_notifier(nb) ({ (void)(nb); })
251 #endif /* CONFIG_HOTPLUG_CPU */
253 #ifdef CONFIG_PM_SLEEP_SMP
254 extern int disable_nonboot_cpus(void);
255 extern void enable_nonboot_cpus(void);
256 #else /* !CONFIG_PM_SLEEP_SMP */
257 static inline int disable_nonboot_cpus(void) { return 0; }
258 static inline void enable_nonboot_cpus(void) {}
259 #endif /* !CONFIG_PM_SLEEP_SMP */
266 void cpu_startup_entry(enum cpuhp_state state);
268 void cpu_idle_poll_ctrl(bool enable);
270 void arch_cpu_idle(void);
271 void arch_cpu_idle_prepare(void);
272 void arch_cpu_idle_enter(void);
273 void arch_cpu_idle_exit(void);
274 void arch_cpu_idle_dead(void);
276 DECLARE_PER_CPU(bool, cpu_dead_idle);
278 int cpu_report_state(int cpu);
279 int cpu_check_up_prepare(int cpu);
280 void cpu_set_state_online(int cpu);
281 #ifdef CONFIG_HOTPLUG_CPU
282 bool cpu_wait_death(unsigned int cpu, int seconds);
283 bool cpu_report_death(void);
284 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
286 #endif /* _LINUX_CPU_H_ */