root/include/linux/cpu.h

INCLUDED FROM

DEFINITIONS

1. cpu_maps_update_begin
2. cpu_maps_update_done
3. cpus_write_lock
4. cpus_write_unlock
5. cpus_read_lock
6. cpus_read_unlock
7. cpus_read_trylock
8. lockdep_assert_cpus_held
9. cpu_hotplug_disable
10. cpu_hotplug_enable
11. cpu_hotplug_begin
12. cpu_hotplug_done
13. get_online_cpus
14. put_online_cpus
15. freeze_secondary_cpus
16. disable_nonboot_cpus
17. suspend_disable_secondary_cpus
18. suspend_enable_secondary_cpus
19. disable_nonboot_cpus
20. enable_nonboot_cpus
21. suspend_disable_secondary_cpus
22. suspend_enable_secondary_cpus
23. cpuhp_report_idle_dead
24. cpu_smt_disable
25. cpu_smt_check_topology
26. cpu_smt_possible
27. cpuhp_smt_enable
28. cpuhp_smt_disable

   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 
  68 extern __printf(4, 5)
  69 struct device *cpu_device_create(struct device *parent, void *drvdata,
  70                                  const struct attribute_group **groups,
  71                                  const char *fmt, ...);
  72 #ifdef CONFIG_HOTPLUG_CPU
  73 extern void unregister_cpu(struct cpu *cpu);
  74 extern ssize_t arch_cpu_probe(const char *, size_t);
  75 extern ssize_t arch_cpu_release(const char *, size_t);
  76 #endif
  77 
  78 /*
  79  * These states are not related to the core CPU hotplug mechanism. They are
  80  * used by various (sub)architectures to track internal state
  81  */
  82 #define CPU_ONLINE              0x0002 /* CPU is up */
  83 #define CPU_UP_PREPARE          0x0003 /* CPU coming up */
  84 #define CPU_DEAD                0x0007 /* CPU dead */
  85 #define CPU_DEAD_FROZEN         0x0008 /* CPU timed out on unplug */
  86 #define CPU_POST_DEAD           0x0009 /* CPU successfully unplugged */
  87 #define CPU_BROKEN              0x000B /* CPU did not die properly */
  88 
  89 #ifdef CONFIG_SMP
  90 extern bool cpuhp_tasks_frozen;
  91 int cpu_up(unsigned int cpu);
  92 void notify_cpu_starting(unsigned int cpu);
  93 extern void cpu_maps_update_begin(void);
  94 extern void cpu_maps_update_done(void);
  95 
  96 #else   /* CONFIG_SMP */
  97 #define cpuhp_tasks_frozen      0
  98 
  99 static inline void cpu_maps_update_begin(void)
 100 {
 101 }
 102 
 103 static inline void cpu_maps_update_done(void)
 104 {
 105 }
 106 
 107 #endif /* CONFIG_SMP */
 108 extern struct bus_type cpu_subsys;
 109 
 110 #ifdef CONFIG_HOTPLUG_CPU
 111 extern void cpus_write_lock(void);
 112 extern void cpus_write_unlock(void);
 113 extern void cpus_read_lock(void);
 114 extern void cpus_read_unlock(void);
 115 extern int  cpus_read_trylock(void);
 116 extern void lockdep_assert_cpus_held(void);
 117 extern void cpu_hotplug_disable(void);
 118 extern void cpu_hotplug_enable(void);
 119 void clear_tasks_mm_cpumask(int cpu);
 120 int cpu_down(unsigned int cpu);
 121 
 122 #else /* CONFIG_HOTPLUG_CPU */
 123 
 124 static inline void cpus_write_lock(void) { }
 125 static inline void cpus_write_unlock(void) { }
 126 static inline void cpus_read_lock(void) { }
 127 static inline void cpus_read_unlock(void) { }
 128 static inline int  cpus_read_trylock(void) { return true; }
 129 static inline void lockdep_assert_cpus_held(void) { }
 130 static inline void cpu_hotplug_disable(void) { }
 131 static inline void cpu_hotplug_enable(void) { }
 132 #endif  /* !CONFIG_HOTPLUG_CPU */
 133 
 134 /* Wrappers which go away once all code is converted */
 135 static inline void cpu_hotplug_begin(void) { cpus_write_lock(); }
 136 static inline void cpu_hotplug_done(void) { cpus_write_unlock(); }
 137 static inline void get_online_cpus(void) { cpus_read_lock(); }
 138 static inline void put_online_cpus(void) { cpus_read_unlock(); }
 139 
 140 #ifdef CONFIG_PM_SLEEP_SMP
 141 int __freeze_secondary_cpus(int primary, bool suspend);
 142 static inline int freeze_secondary_cpus(int primary)
 143 {
 144         return __freeze_secondary_cpus(primary, true);
 145 }
 146 
 147 static inline int disable_nonboot_cpus(void)
 148 {
 149         return __freeze_secondary_cpus(0, false);
 150 }
 151 
 152 void enable_nonboot_cpus(void);
 153 
 154 static inline int suspend_disable_secondary_cpus(void)
 155 {
 156         int cpu = 0;
 157 
 158         if (IS_ENABLED(CONFIG_PM_SLEEP_SMP_NONZERO_CPU))
 159                 cpu = -1;
 160 
 161         return freeze_secondary_cpus(cpu);
 162 }
 163 static inline void suspend_enable_secondary_cpus(void)
 164 {
 165         return enable_nonboot_cpus();
 166 }
 167 
 168 #else /* !CONFIG_PM_SLEEP_SMP */
 169 static inline int disable_nonboot_cpus(void) { return 0; }
 170 static inline void enable_nonboot_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 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       __attribute__((__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(unsigned long duration_us);
 194 
 195 #ifdef CONFIG_HOTPLUG_CPU
 196 bool cpu_wait_death(unsigned int cpu, int seconds);
 197 bool cpu_report_death(void);
 198 void cpuhp_report_idle_dead(void);
 199 #else
 200 static inline void cpuhp_report_idle_dead(void) { }
 201 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
 202 
 203 enum cpuhp_smt_control {
 204         CPU_SMT_ENABLED,
 205         CPU_SMT_DISABLED,
 206         CPU_SMT_FORCE_DISABLED,
 207         CPU_SMT_NOT_SUPPORTED,
 208         CPU_SMT_NOT_IMPLEMENTED,
 209 };
 210 
 211 #if defined(CONFIG_SMP) && defined(CONFIG_HOTPLUG_SMT)
 212 extern enum cpuhp_smt_control cpu_smt_control;
 213 extern void cpu_smt_disable(bool force);
 214 extern void cpu_smt_check_topology(void);
 215 extern bool cpu_smt_possible(void);
 216 extern int cpuhp_smt_enable(void);
 217 extern int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval);
 218 #else
 219 # define cpu_smt_control                (CPU_SMT_NOT_IMPLEMENTED)
 220 static inline void cpu_smt_disable(bool force) { }
 221 static inline void cpu_smt_check_topology(void) { }
 222 static inline bool cpu_smt_possible(void) { return false; }
 223 static inline int cpuhp_smt_enable(void) { return 0; }
 224 static inline int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval) { return 0; }
 225 #endif
 226 
 227 extern bool cpu_mitigations_off(void);
 228 extern bool cpu_mitigations_auto_nosmt(void);
 229 
 230 #endif /* _LINUX_CPU_H_ */