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,
74 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */
75 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */
76 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */
77 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */
78 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */
79 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */
80 #define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task,
81 * not handling interrupts, soon dead.
82 * Called on the dying cpu, interrupts
83 * are already disabled. Must not
84 * sleep, must not fail */
85 #define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug
87 #define CPU_STARTING 0x000A /* CPU (unsigned)v soon running.
88 * Called on the new cpu, just before
89 * enabling interrupts. Must not sleep,
92 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
93 * operation in progress
95 #define CPU_TASKS_FROZEN 0x0010
97 #define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN)
98 #define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN)
99 #define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
100 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
101 #define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
102 #define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN)
103 #define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN)
104 #define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN)
108 /* Need to know about CPUs going up/down? */
109 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
110 #define cpu_notifier(fn, pri) { \
111 static struct notifier_block fn##_nb __cpuinitdata = \
112 { .notifier_call = fn, .priority = pri }; \
113 register_cpu_notifier(&fn##_nb); \
115 extern int register_cpu_notifier(struct notifier_block *nb);
116 extern void unregister_cpu_notifier(struct notifier_block *nb);
118 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
119 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
121 static inline int register_cpu_notifier(struct notifier_block *nb)
126 static inline void unregister_cpu_notifier(struct notifier_block *nb)
131 int cpu_up(unsigned int cpu);
132 void notify_cpu_starting(unsigned int cpu);
133 extern void cpu_maps_update_begin(void);
134 extern void cpu_maps_update_done(void);
136 #else /* CONFIG_SMP */
138 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
140 static inline int register_cpu_notifier(struct notifier_block *nb)
145 static inline void unregister_cpu_notifier(struct notifier_block *nb)
149 static inline void cpu_maps_update_begin(void)
153 static inline void cpu_maps_update_done(void)
157 #endif /* CONFIG_SMP */
158 extern struct sysdev_class cpu_sysdev_class;
160 #ifdef CONFIG_HOTPLUG_CPU
161 /* Stop CPUs going up and down. */
163 extern void get_online_cpus(void);
164 extern void put_online_cpus(void);
165 extern void cpu_hotplug_disable(void);
166 extern void cpu_hotplug_enable(void);
167 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri)
168 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
169 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
170 int cpu_down(unsigned int cpu);
172 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
173 extern void cpu_hotplug_driver_lock(void);
174 extern void cpu_hotplug_driver_unlock(void);
176 static inline void cpu_hotplug_driver_lock(void)
180 static inline void cpu_hotplug_driver_unlock(void)
185 #else /* CONFIG_HOTPLUG_CPU */
187 #define get_online_cpus() do { } while (0)
188 #define put_online_cpus() do { } while (0)
189 #define cpu_hotplug_disable() do { } while (0)
190 #define cpu_hotplug_enable() do { } while (0)
191 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
192 /* These aren't inline functions due to a GCC bug. */
193 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; })
194 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); })
195 #endif /* CONFIG_HOTPLUG_CPU */
197 #ifdef CONFIG_PM_SLEEP_SMP
198 extern int disable_nonboot_cpus(void);
199 extern void enable_nonboot_cpus(void);
200 #else /* !CONFIG_PM_SLEEP_SMP */
201 static inline int disable_nonboot_cpus(void) { return 0; }
202 static inline void enable_nonboot_cpus(void) {}
203 #endif /* !CONFIG_PM_SLEEP_SMP */
205 #endif /* _LINUX_CPU_H_ */