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1/*
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 *
11 * CPUs are exported via sysfs in the class/cpu/devices/
12 * directory.
13 */
14#ifndef _LINUX_CPU_H_
15#define _LINUX_CPU_H_
16
17#include <linux/device.h>
18#include <linux/node.h>
19#include <linux/compiler.h>
20#include <linux/cpumask.h>
21
22struct cpu {
23 int node_id; /* The node which contains the CPU */
24 int hotpluggable; /* creates sysfs control file if hotpluggable */
25 struct device dev;
26};
27
28extern int register_cpu(struct cpu *cpu, int num);
29extern struct device *get_cpu_device(unsigned cpu);
30extern bool cpu_is_hotpluggable(unsigned cpu);
31
32extern int cpu_add_dev_attr(struct device_attribute *attr);
33extern void cpu_remove_dev_attr(struct device_attribute *attr);
34
35extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
36extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
37
38extern int sched_create_sysfs_power_savings_entries(struct device *dev);
39
40#ifdef CONFIG_HOTPLUG_CPU
41extern void unregister_cpu(struct cpu *cpu);
42extern ssize_t arch_cpu_probe(const char *, size_t);
43extern ssize_t arch_cpu_release(const char *, size_t);
44#endif
45struct notifier_block;
46
47/*
48 * CPU notifier priorities.
49 */
50enum {
51 /*
52 * SCHED_ACTIVE marks a cpu which is coming up active during
53 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first
54 * notifier. CPUSET_ACTIVE adjusts cpuset according to
55 * cpu_active mask right after SCHED_ACTIVE. During
56 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are
57 * ordered in the similar way.
58 *
59 * This ordering guarantees consistent cpu_active mask and
60 * migration behavior to all cpu notifiers.
61 */
62 CPU_PRI_SCHED_ACTIVE = INT_MAX,
63 CPU_PRI_CPUSET_ACTIVE = INT_MAX - 1,
64 CPU_PRI_SCHED_INACTIVE = INT_MIN + 1,
65 CPU_PRI_CPUSET_INACTIVE = INT_MIN,
66
67 /* migration should happen before other stuff but after perf */
68 CPU_PRI_PERF = 20,
69 CPU_PRI_MIGRATION = 10,
70 /* prepare workqueues for other notifiers */
71 CPU_PRI_WORKQUEUE = 5,
72};
73
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
86 * lock is dropped */
87#define CPU_STARTING 0x000A /* CPU (unsigned)v soon running.
88 * Called on the new cpu, just before
89 * enabling interrupts. Must not sleep,
90 * must not fail */
91
92/* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
93 * operation in progress
94 */
95#define CPU_TASKS_FROZEN 0x0010
96
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)
105
106
107#ifdef CONFIG_SMP
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); \
114}
115#else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
116#define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
117#endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
118#ifdef CONFIG_HOTPLUG_CPU
119extern int register_cpu_notifier(struct notifier_block *nb);
120extern void unregister_cpu_notifier(struct notifier_block *nb);
121#else
122
123#ifndef MODULE
124extern int register_cpu_notifier(struct notifier_block *nb);
125#else
126static inline int register_cpu_notifier(struct notifier_block *nb)
127{
128 return 0;
129}
130#endif
131
132static inline void unregister_cpu_notifier(struct notifier_block *nb)
133{
134}
135#endif
136
137int cpu_up(unsigned int cpu);
138void notify_cpu_starting(unsigned int cpu);
139extern void cpu_maps_update_begin(void);
140extern void cpu_maps_update_done(void);
141
142#else /* CONFIG_SMP */
143
144#define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
145
146static inline int register_cpu_notifier(struct notifier_block *nb)
147{
148 return 0;
149}
150
151static inline void unregister_cpu_notifier(struct notifier_block *nb)
152{
153}
154
155static inline void cpu_maps_update_begin(void)
156{
157}
158
159static inline void cpu_maps_update_done(void)
160{
161}
162
163#endif /* CONFIG_SMP */
164extern struct bus_type cpu_subsys;
165
166#ifdef CONFIG_HOTPLUG_CPU
167/* Stop CPUs going up and down. */
168
169extern void get_online_cpus(void);
170extern void put_online_cpus(void);
171#define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri)
172#define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
173#define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
174int cpu_down(unsigned int cpu);
175
176#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
177extern void cpu_hotplug_driver_lock(void);
178extern void cpu_hotplug_driver_unlock(void);
179#else
180static inline void cpu_hotplug_driver_lock(void)
181{
182}
183
184static inline void cpu_hotplug_driver_unlock(void)
185{
186}
187#endif
188
189#else /* CONFIG_HOTPLUG_CPU */
190
191#define get_online_cpus() do { } while (0)
192#define put_online_cpus() do { } while (0)
193#define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
194/* These aren't inline functions due to a GCC bug. */
195#define register_hotcpu_notifier(nb) ({ (void)(nb); 0; })
196#define unregister_hotcpu_notifier(nb) ({ (void)(nb); })
197#endif /* CONFIG_HOTPLUG_CPU */
198
199#ifdef CONFIG_PM_SLEEP_SMP
200extern int disable_nonboot_cpus(void);
201extern void enable_nonboot_cpus(void);
202#else /* !CONFIG_PM_SLEEP_SMP */
203static inline int disable_nonboot_cpus(void) { return 0; }
204static inline void enable_nonboot_cpus(void) {}
205#endif /* !CONFIG_PM_SLEEP_SMP */
206
207#endif /* _LINUX_CPU_H_ */