summaryrefslogtreecommitdiff
path: root/include/linux/cpu.h
blob: 956c0a16566f828a37773b8a913423921f3a3079 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
/*
 * include/linux/cpu.h - generic cpu definition
 *
 * This is mainly for topological representation. We define the 
 * basic 'struct cpu' here, which can be embedded in per-arch 
 * definitions of processors.
 *
 * Basic handling of the devices is done in drivers/base/cpu.c
 *
 * CPUs are exported via sysfs in the devices/system/cpu
 * directory. 
 */
#ifndef _LINUX_CPU_H_
#define _LINUX_CPU_H_

#include <linux/node.h>
#include <linux/compiler.h>
#include <linux/cpumask.h>

struct device;

struct cpu {
	int node_id;		/* The node which contains the CPU */
	int hotpluggable;	/* creates sysfs control file if hotpluggable */
	struct device dev;
};

extern int register_cpu(struct cpu *cpu, int num);
extern struct device *get_cpu_device(unsigned cpu);
extern bool cpu_is_hotpluggable(unsigned cpu);

extern int cpu_add_dev_attr(struct device_attribute *attr);
extern void cpu_remove_dev_attr(struct device_attribute *attr);

extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);

#ifdef CONFIG_HOTPLUG_CPU
extern void unregister_cpu(struct cpu *cpu);
extern ssize_t arch_cpu_probe(const char *, size_t);
extern ssize_t arch_cpu_release(const char *, size_t);
#endif
struct notifier_block;

#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
extern int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env);
extern ssize_t arch_print_cpu_modalias(struct device *dev,
				       struct device_attribute *attr,
				       char *bufptr);
#endif

/*
 * CPU notifier priorities.
 */
enum {
	/*
	 * SCHED_ACTIVE marks a cpu which is coming up active during
	 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first
	 * notifier.  CPUSET_ACTIVE adjusts cpuset according to
	 * cpu_active mask right after SCHED_ACTIVE.  During
	 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are
	 * ordered in the similar way.
	 *
	 * This ordering guarantees consistent cpu_active mask and
	 * migration behavior to all cpu notifiers.
	 */
	CPU_PRI_SCHED_ACTIVE	= INT_MAX,
	CPU_PRI_CPUSET_ACTIVE	= INT_MAX - 1,
	CPU_PRI_SCHED_INACTIVE	= INT_MIN + 1,
	CPU_PRI_CPUSET_INACTIVE	= INT_MIN,

	/* migration should happen before other stuff but after perf */
	CPU_PRI_PERF		= 20,
	CPU_PRI_MIGRATION	= 10,
	/* bring up workqueues before normal notifiers and down after */
	CPU_PRI_WORKQUEUE_UP	= 5,
	CPU_PRI_WORKQUEUE_DOWN	= -5,
};

#define CPU_ONLINE		0x0002 /* CPU (unsigned)v is up */
#define CPU_UP_PREPARE		0x0003 /* CPU (unsigned)v coming up */
#define CPU_UP_CANCELED		0x0004 /* CPU (unsigned)v NOT coming up */
#define CPU_DOWN_PREPARE	0x0005 /* CPU (unsigned)v going down */
#define CPU_DOWN_FAILED		0x0006 /* CPU (unsigned)v NOT going down */
#define CPU_DEAD		0x0007 /* CPU (unsigned)v dead */
#define CPU_DYING		0x0008 /* CPU (unsigned)v not running any task,
					* not handling interrupts, soon dead.
					* Called on the dying cpu, interrupts
					* are already disabled. Must not
					* sleep, must not fail */
#define CPU_POST_DEAD		0x0009 /* CPU (unsigned)v dead, cpu_hotplug
					* lock is dropped */
#define CPU_STARTING		0x000A /* CPU (unsigned)v soon running.
					* Called on the new cpu, just before
					* enabling interrupts. Must not sleep,
					* must not fail */

/* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
 * operation in progress
 */
#define CPU_TASKS_FROZEN	0x0010

#define CPU_ONLINE_FROZEN	(CPU_ONLINE | CPU_TASKS_FROZEN)
#define CPU_UP_PREPARE_FROZEN	(CPU_UP_PREPARE | CPU_TASKS_FROZEN)
#define CPU_UP_CANCELED_FROZEN	(CPU_UP_CANCELED | CPU_TASKS_FROZEN)
#define CPU_DOWN_PREPARE_FROZEN	(CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
#define CPU_DOWN_FAILED_FROZEN	(CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
#define CPU_DEAD_FROZEN		(CPU_DEAD | CPU_TASKS_FROZEN)
#define CPU_DYING_FROZEN	(CPU_DYING | CPU_TASKS_FROZEN)
#define CPU_STARTING_FROZEN	(CPU_STARTING | CPU_TASKS_FROZEN)


#ifdef CONFIG_SMP
/* Need to know about CPUs going up/down? */
#if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
#define cpu_notifier(fn, pri) {					\
	static struct notifier_block fn##_nb =			\
		{ .notifier_call = fn, .priority = pri };	\
	register_cpu_notifier(&fn##_nb);			\
}
#else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
#define cpu_notifier(fn, pri)	do { (void)(fn); } while (0)
#endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
#ifdef CONFIG_HOTPLUG_CPU
extern int register_cpu_notifier(struct notifier_block *nb);
extern void unregister_cpu_notifier(struct notifier_block *nb);
#else

#ifndef MODULE
extern int register_cpu_notifier(struct notifier_block *nb);
#else
static inline int register_cpu_notifier(struct notifier_block *nb)
{
	return 0;
}
#endif

static inline void unregister_cpu_notifier(struct notifier_block *nb)
{
}
#endif

int cpu_up(unsigned int cpu);
void notify_cpu_starting(unsigned int cpu);
extern void cpu_maps_update_begin(void);
extern void cpu_maps_update_done(void);

#else	/* CONFIG_SMP */

#define cpu_notifier(fn, pri)	do { (void)(fn); } while (0)

static inline int register_cpu_notifier(struct notifier_block *nb)
{
	return 0;
}

static inline void unregister_cpu_notifier(struct notifier_block *nb)
{
}

static inline void cpu_maps_update_begin(void)
{
}

static inline void cpu_maps_update_done(void)
{
}

#endif /* CONFIG_SMP */
extern struct bus_type cpu_subsys;

#ifdef CONFIG_HOTPLUG_CPU
/* Stop CPUs going up and down. */

extern void cpu_hotplug_begin(void);
extern void cpu_hotplug_done(void);
extern void get_online_cpus(void);
extern void put_online_cpus(void);
extern void cpu_hotplug_disable(void);
extern void cpu_hotplug_enable(void);
#define hotcpu_notifier(fn, pri)	cpu_notifier(fn, pri)
#define register_hotcpu_notifier(nb)	register_cpu_notifier(nb)
#define unregister_hotcpu_notifier(nb)	unregister_cpu_notifier(nb)
void clear_tasks_mm_cpumask(int cpu);
int cpu_down(unsigned int cpu);

#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
extern void cpu_hotplug_driver_lock(void);
extern void cpu_hotplug_driver_unlock(void);
#else
static inline void cpu_hotplug_driver_lock(void)
{
}

static inline void cpu_hotplug_driver_unlock(void)
{
}
#endif

#else		/* CONFIG_HOTPLUG_CPU */

static inline void cpu_hotplug_begin(void) {}
static inline void cpu_hotplug_done(void) {}
#define get_online_cpus()	do { } while (0)
#define put_online_cpus()	do { } while (0)
#define cpu_hotplug_disable()	do { } while (0)
#define cpu_hotplug_enable()	do { } while (0)
#define hotcpu_notifier(fn, pri)	do { (void)(fn); } while (0)
/* These aren't inline functions due to a GCC bug. */
#define register_hotcpu_notifier(nb)	({ (void)(nb); 0; })
#define unregister_hotcpu_notifier(nb)	({ (void)(nb); })
#endif		/* CONFIG_HOTPLUG_CPU */

#ifdef CONFIG_PM_SLEEP_SMP
extern int disable_nonboot_cpus(void);
extern void enable_nonboot_cpus(void);
#else /* !CONFIG_PM_SLEEP_SMP */
static inline int disable_nonboot_cpus(void) { return 0; }
static inline void enable_nonboot_cpus(void) {}
#endif /* !CONFIG_PM_SLEEP_SMP */

enum cpuhp_state {
	CPUHP_OFFLINE,
	CPUHP_ONLINE,
};

void cpu_startup_entry(enum cpuhp_state state);
void cpu_idle(void);

void cpu_idle_poll_ctrl(bool enable);

void arch_cpu_idle(void);
void arch_cpu_idle_prepare(void);
void arch_cpu_idle_enter(void);
void arch_cpu_idle_exit(void);
void arch_cpu_idle_dead(void);

#endif /* _LINUX_CPU_H_ */