xref: /linux-6.15/include/linux/cpu.h (revision cee2cfb7)
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  *
10  * CPUs are exported via sysfs in the devices/system/cpu
11  * directory.
12  */
13 #ifndef _LINUX_CPU_H_
14 #define _LINUX_CPU_H_
15 
16 #include <linux/node.h>
17 #include <linux/compiler.h>
18 #include <linux/cpumask.h>
19 #include <linux/cpuhotplug.h>
20 
21 struct device;
22 struct device_node;
23 struct attribute_group;
24 
25 struct cpu {
26 	int node_id;		/* The node which contains the CPU */
27 	int hotpluggable;	/* creates sysfs control file if hotpluggable */
28 	struct device dev;
29 };
30 
31 extern void boot_cpu_init(void);
32 extern void boot_cpu_state_init(void);
33 
34 extern int register_cpu(struct cpu *cpu, int num);
35 extern struct device *get_cpu_device(unsigned cpu);
36 extern bool cpu_is_hotpluggable(unsigned cpu);
37 extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id);
38 extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
39 					      int cpu, unsigned int *thread);
40 
41 extern int cpu_add_dev_attr(struct device_attribute *attr);
42 extern void cpu_remove_dev_attr(struct device_attribute *attr);
43 
44 extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
45 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
46 
47 extern __printf(4, 5)
48 struct device *cpu_device_create(struct device *parent, void *drvdata,
49 				 const struct attribute_group **groups,
50 				 const char *fmt, ...);
51 #ifdef CONFIG_HOTPLUG_CPU
52 extern void unregister_cpu(struct cpu *cpu);
53 extern ssize_t arch_cpu_probe(const char *, size_t);
54 extern ssize_t arch_cpu_release(const char *, size_t);
55 #endif
56 struct notifier_block;
57 
58 #define CPU_ONLINE		0x0002 /* CPU (unsigned)v is up */
59 #define CPU_UP_PREPARE		0x0003 /* CPU (unsigned)v coming up */
60 #define CPU_DEAD		0x0007 /* CPU (unsigned)v dead */
61 #define CPU_POST_DEAD		0x0009 /* CPU (unsigned)v dead, cpu_hotplug
62 					* lock is dropped */
63 #define CPU_BROKEN		0x000B /* CPU (unsigned)v did not die properly,
64 					* perhaps due to preemption. */
65 
66 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
67  * operation in progress
68  */
69 #define CPU_TASKS_FROZEN	0x0010
70 
71 #define CPU_ONLINE_FROZEN	(CPU_ONLINE | CPU_TASKS_FROZEN)
72 #define CPU_UP_PREPARE_FROZEN	(CPU_UP_PREPARE | CPU_TASKS_FROZEN)
73 #define CPU_UP_CANCELED_FROZEN	(CPU_UP_CANCELED | CPU_TASKS_FROZEN)
74 #define CPU_DOWN_PREPARE_FROZEN	(CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
75 #define CPU_DOWN_FAILED_FROZEN	(CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
76 #define CPU_DEAD_FROZEN		(CPU_DEAD | CPU_TASKS_FROZEN)
77 
78 #ifdef CONFIG_SMP
79 extern bool cpuhp_tasks_frozen;
80 int cpu_up(unsigned int cpu);
81 void notify_cpu_starting(unsigned int cpu);
82 extern void cpu_maps_update_begin(void);
83 extern void cpu_maps_update_done(void);
84 
85 #else	/* CONFIG_SMP */
86 #define cpuhp_tasks_frozen	0
87 
88 static inline void cpu_maps_update_begin(void)
89 {
90 }
91 
92 static inline void cpu_maps_update_done(void)
93 {
94 }
95 
96 #endif /* CONFIG_SMP */
97 extern struct bus_type cpu_subsys;
98 
99 #ifdef CONFIG_HOTPLUG_CPU
100 /* Stop CPUs going up and down. */
101 
102 extern void cpu_hotplug_begin(void);
103 extern void cpu_hotplug_done(void);
104 extern void get_online_cpus(void);
105 extern void put_online_cpus(void);
106 extern void cpu_hotplug_disable(void);
107 extern void cpu_hotplug_enable(void);
108 void clear_tasks_mm_cpumask(int cpu);
109 int cpu_down(unsigned int cpu);
110 
111 #else		/* CONFIG_HOTPLUG_CPU */
112 
113 static inline void cpu_hotplug_begin(void) {}
114 static inline void cpu_hotplug_done(void) {}
115 #define get_online_cpus()	do { } while (0)
116 #define put_online_cpus()	do { } while (0)
117 #define cpu_hotplug_disable()	do { } while (0)
118 #define cpu_hotplug_enable()	do { } while (0)
119 #endif		/* CONFIG_HOTPLUG_CPU */
120 
121 #ifdef CONFIG_PM_SLEEP_SMP
122 extern int freeze_secondary_cpus(int primary);
123 static inline int disable_nonboot_cpus(void)
124 {
125 	return freeze_secondary_cpus(0);
126 }
127 extern void enable_nonboot_cpus(void);
128 #else /* !CONFIG_PM_SLEEP_SMP */
129 static inline int disable_nonboot_cpus(void) { return 0; }
130 static inline void enable_nonboot_cpus(void) {}
131 #endif /* !CONFIG_PM_SLEEP_SMP */
132 
133 void cpu_startup_entry(enum cpuhp_state state);
134 
135 void cpu_idle_poll_ctrl(bool enable);
136 
137 /* Attach to any functions which should be considered cpuidle. */
138 #define __cpuidle	__attribute__((__section__(".cpuidle.text")))
139 
140 bool cpu_in_idle(unsigned long pc);
141 
142 void arch_cpu_idle(void);
143 void arch_cpu_idle_prepare(void);
144 void arch_cpu_idle_enter(void);
145 void arch_cpu_idle_exit(void);
146 void arch_cpu_idle_dead(void);
147 
148 int cpu_report_state(int cpu);
149 int cpu_check_up_prepare(int cpu);
150 void cpu_set_state_online(int cpu);
151 void play_idle(unsigned long duration_ms);
152 
153 #ifdef CONFIG_HOTPLUG_CPU
154 bool cpu_wait_death(unsigned int cpu, int seconds);
155 bool cpu_report_death(void);
156 void cpuhp_report_idle_dead(void);
157 #else
158 static inline void cpuhp_report_idle_dead(void) { }
159 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
160 
161 #endif /* _LINUX_CPU_H_ */
162