1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | * include/linux/cpu.h - generic cpu definition |
4 | * |
5 | * This is mainly for topological representation. We define the |
6 | * basic 'struct cpu' here, which can be embedded in per-arch |
7 | * definitions of processors. |
8 | * |
9 | * Basic handling of the devices is done in drivers/base/cpu.c |
10 | * |
11 | * CPUs are exported via sysfs in the devices/system/cpu |
12 | * directory. |
13 | */ |
14 | #ifndef _LINUX_CPU_H_ |
15 | #define _LINUX_CPU_H_ |
16 | |
17 | #include <linux/node.h> |
18 | #include <linux/compiler.h> |
19 | #include <linux/cpumask.h> |
20 | #include <linux/cpuhotplug.h> |
21 | |
22 | struct device; |
23 | struct device_node; |
24 | struct attribute_group; |
25 | |
26 | struct cpu { |
27 | int node_id; /* The node which contains the CPU */ |
28 | int hotpluggable; /* creates sysfs control file if hotpluggable */ |
29 | struct device dev; |
30 | }; |
31 | |
32 | extern void boot_cpu_init(void); |
33 | extern void boot_cpu_hotplug_init(void); |
34 | extern void cpu_init(void); |
35 | extern void trap_init(void); |
36 | |
37 | extern int register_cpu(struct cpu *cpu, int num); |
38 | extern struct device *get_cpu_device(unsigned cpu); |
39 | extern bool cpu_is_hotpluggable(unsigned cpu); |
40 | extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id); |
41 | extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, |
42 | int cpu, unsigned int *thread); |
43 | |
44 | extern int cpu_add_dev_attr(struct device_attribute *attr); |
45 | extern void cpu_remove_dev_attr(struct device_attribute *attr); |
46 | |
47 | extern int cpu_add_dev_attr_group(struct attribute_group *attrs); |
48 | extern void cpu_remove_dev_attr_group(struct attribute_group *attrs); |
49 | |
50 | extern ssize_t cpu_show_meltdown(struct device *dev, |
51 | struct device_attribute *attr, char *buf); |
52 | extern ssize_t cpu_show_spectre_v1(struct device *dev, |
53 | struct device_attribute *attr, char *buf); |
54 | extern ssize_t cpu_show_spectre_v2(struct device *dev, |
55 | struct device_attribute *attr, char *buf); |
56 | extern ssize_t cpu_show_spec_store_bypass(struct device *dev, |
57 | struct device_attribute *attr, char *buf); |
58 | extern ssize_t cpu_show_l1tf(struct device *dev, |
59 | struct device_attribute *attr, char *buf); |
60 | extern ssize_t cpu_show_mds(struct device *dev, |
61 | struct device_attribute *attr, char *buf); |
62 | extern ssize_t cpu_show_tsx_async_abort(struct device *dev, |
63 | struct device_attribute *attr, |
64 | char *buf); |
65 | extern ssize_t cpu_show_itlb_multihit(struct device *dev, |
66 | struct device_attribute *attr, char *buf); |
67 | extern ssize_t cpu_show_srbds(struct device *dev, struct device_attribute *attr, char *buf); |
68 | extern ssize_t cpu_show_mmio_stale_data(struct device *dev, |
69 | struct device_attribute *attr, |
70 | char *buf); |
71 | extern ssize_t cpu_show_retbleed(struct device *dev, |
72 | struct device_attribute *attr, char *buf); |
73 | |
74 | extern __printf(4, 5) |
75 | struct device *cpu_device_create(struct device *parent, void *drvdata, |
76 | const struct attribute_group **groups, |
77 | const char *fmt, ...); |
78 | #ifdef CONFIG_HOTPLUG_CPU |
79 | extern void unregister_cpu(struct cpu *cpu); |
80 | extern ssize_t arch_cpu_probe(const char *, size_t); |
81 | extern ssize_t arch_cpu_release(const char *, size_t); |
82 | #endif |
83 | |
84 | /* |
85 | * These states are not related to the core CPU hotplug mechanism. They are |
86 | * used by various (sub)architectures to track internal state |
87 | */ |
88 | #define CPU_ONLINE 0x0002 /* CPU is up */ |
89 | #define CPU_UP_PREPARE 0x0003 /* CPU coming up */ |
90 | #define CPU_DEAD 0x0007 /* CPU dead */ |
91 | #define CPU_DEAD_FROZEN 0x0008 /* CPU timed out on unplug */ |
92 | #define CPU_POST_DEAD 0x0009 /* CPU successfully unplugged */ |
93 | #define CPU_BROKEN 0x000B /* CPU did not die properly */ |
94 | |
95 | #ifdef CONFIG_SMP |
96 | extern bool cpuhp_tasks_frozen; |
97 | int add_cpu(unsigned int cpu); |
98 | int cpu_device_up(struct device *dev); |
99 | void notify_cpu_starting(unsigned int cpu); |
100 | extern void cpu_maps_update_begin(void); |
101 | extern void cpu_maps_update_done(void); |
102 | int bringup_hibernate_cpu(unsigned int sleep_cpu); |
103 | void bringup_nonboot_cpus(unsigned int setup_max_cpus); |
104 | |
105 | #else /* CONFIG_SMP */ |
106 | #define cpuhp_tasks_frozen 0 |
107 | |
108 | static inline void cpu_maps_update_begin(void) |
109 | { |
110 | } |
111 | |
112 | static inline void cpu_maps_update_done(void) |
113 | { |
114 | } |
115 | |
116 | static inline int add_cpu(unsigned int cpu) { return 0;} |
117 | |
118 | #endif /* CONFIG_SMP */ |
119 | extern struct bus_type cpu_subsys; |
120 | |
121 | extern int lockdep_is_cpus_held(void); |
122 | |
123 | #ifdef CONFIG_HOTPLUG_CPU |
124 | extern void cpus_write_lock(void); |
125 | extern void cpus_write_unlock(void); |
126 | extern void cpus_read_lock(void); |
127 | extern void cpus_read_unlock(void); |
128 | extern int cpus_read_trylock(void); |
129 | extern void lockdep_assert_cpus_held(void); |
130 | extern void cpu_hotplug_disable(void); |
131 | extern void cpu_hotplug_enable(void); |
132 | void clear_tasks_mm_cpumask(int cpu); |
133 | int remove_cpu(unsigned int cpu); |
134 | int cpu_device_down(struct device *dev); |
135 | extern void smp_shutdown_nonboot_cpus(unsigned int primary_cpu); |
136 | |
137 | #else /* CONFIG_HOTPLUG_CPU */ |
138 | |
139 | static inline void cpus_write_lock(void) { } |
140 | static inline void cpus_write_unlock(void) { } |
141 | static inline void cpus_read_lock(void) { } |
142 | static inline void cpus_read_unlock(void) { } |
143 | static inline int cpus_read_trylock(void) { return true; } |
144 | static inline void lockdep_assert_cpus_held(void) { } |
145 | static inline void cpu_hotplug_disable(void) { } |
146 | static inline void cpu_hotplug_enable(void) { } |
147 | static inline int remove_cpu(unsigned int cpu) { return -EPERM; } |
148 | static inline void smp_shutdown_nonboot_cpus(unsigned int primary_cpu) { } |
149 | #endif /* !CONFIG_HOTPLUG_CPU */ |
150 | |
151 | #ifdef CONFIG_PM_SLEEP_SMP |
152 | extern int freeze_secondary_cpus(int primary); |
153 | extern void thaw_secondary_cpus(void); |
154 | |
155 | static inline int suspend_disable_secondary_cpus(void) |
156 | { |
157 | int cpu = 0; |
158 | |
159 | if (IS_ENABLED(CONFIG_PM_SLEEP_SMP_NONZERO_CPU)) |
160 | cpu = -1; |
161 | |
162 | return freeze_secondary_cpus(cpu); |
163 | } |
164 | static inline void suspend_enable_secondary_cpus(void) |
165 | { |
166 | return thaw_secondary_cpus(); |
167 | } |
168 | |
169 | #else /* !CONFIG_PM_SLEEP_SMP */ |
170 | static inline void thaw_secondary_cpus(void) {} |
171 | static inline int suspend_disable_secondary_cpus(void) { return 0; } |
172 | static inline void suspend_enable_secondary_cpus(void) { } |
173 | #endif /* !CONFIG_PM_SLEEP_SMP */ |
174 | |
175 | void __noreturn cpu_startup_entry(enum cpuhp_state state); |
176 | |
177 | void cpu_idle_poll_ctrl(bool enable); |
178 | |
179 | /* Attach to any functions which should be considered cpuidle. */ |
180 | #define __cpuidle __section(".cpuidle.text") |
181 | |
182 | bool cpu_in_idle(unsigned long pc); |
183 | |
184 | void arch_cpu_idle(void); |
185 | void arch_cpu_idle_prepare(void); |
186 | void arch_cpu_idle_enter(void); |
187 | void arch_cpu_idle_exit(void); |
188 | void arch_cpu_idle_dead(void); |
189 | |
190 | int cpu_report_state(int cpu); |
191 | int cpu_check_up_prepare(int cpu); |
192 | void cpu_set_state_online(int cpu); |
193 | void play_idle_precise(u64 duration_ns, u64 latency_ns); |
194 | |
195 | static inline void play_idle(unsigned long duration_us) |
196 | { |
197 | play_idle_precise(duration_us * NSEC_PER_USEC, U64_MAX); |
198 | } |
199 | |
200 | #ifdef CONFIG_HOTPLUG_CPU |
201 | bool cpu_wait_death(unsigned int cpu, int seconds); |
202 | bool cpu_report_death(void); |
203 | void cpuhp_report_idle_dead(void); |
204 | #else |
205 | static inline void cpuhp_report_idle_dead(void) { } |
206 | #endif /* #ifdef CONFIG_HOTPLUG_CPU */ |
207 | |
208 | enum cpuhp_smt_control { |
209 | CPU_SMT_ENABLED, |
210 | CPU_SMT_DISABLED, |
211 | CPU_SMT_FORCE_DISABLED, |
212 | CPU_SMT_NOT_SUPPORTED, |
213 | CPU_SMT_NOT_IMPLEMENTED, |
214 | }; |
215 | |
216 | #if defined(CONFIG_SMP) && defined(CONFIG_HOTPLUG_SMT) |
217 | extern enum cpuhp_smt_control cpu_smt_control; |
218 | extern void cpu_smt_disable(bool force); |
219 | extern void cpu_smt_check_topology(void); |
220 | extern bool cpu_smt_possible(void); |
221 | extern int cpuhp_smt_enable(void); |
222 | extern int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval); |
223 | #else |
224 | # define cpu_smt_control (CPU_SMT_NOT_IMPLEMENTED) |
225 | static inline void cpu_smt_disable(bool force) { } |
226 | static inline void cpu_smt_check_topology(void) { } |
227 | static inline bool cpu_smt_possible(void) { return false; } |
228 | static inline int cpuhp_smt_enable(void) { return 0; } |
229 | static inline int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval) { return 0; } |
230 | #endif |
231 | |
232 | extern bool cpu_mitigations_off(void); |
233 | extern bool cpu_mitigations_auto_nosmt(void); |
234 | |
235 | #endif /* _LINUX_CPU_H_ */ |
236 | |