LXR linux/include/linux/cpu.h

   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
  22struct device;
  23struct device_node;
  24struct attribute_group;
  25
  26struct 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
  32extern void boot_cpu_init(void);
  33extern void boot_cpu_state_init(void);
  34extern void cpu_init(void);
  35extern void trap_init(void);
  36
  37extern int register_cpu(struct cpu *cpu, int num);
  38extern struct device *get_cpu_device(unsigned cpu);
  39extern bool cpu_is_hotpluggable(unsigned cpu);
  40extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id);
  41extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
  42                                              int cpu, unsigned int *thread);
  43
  44extern int cpu_add_dev_attr(struct device_attribute *attr);
  45extern void cpu_remove_dev_attr(struct device_attribute *attr);
  46
  47extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
  48extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
  49
  50extern __printf(4, 5)
  51struct device *cpu_device_create(struct device *parent, void *drvdata,
  52                                 const struct attribute_group **groups,
  53                                 const char *fmt, ...);
  54#ifdef CONFIG_HOTPLUG_CPU
  55extern void unregister_cpu(struct cpu *cpu);
  56extern ssize_t arch_cpu_probe(const char *, size_t);
  57extern ssize_t arch_cpu_release(const char *, size_t);
  58#endif
  59struct notifier_block;
  60
  61#define CPU_ONLINE              0x0002 /* CPU (unsigned)v is up */
  62#define CPU_UP_PREPARE          0x0003 /* CPU (unsigned)v coming up */
  63#define CPU_DEAD                0x0007 /* CPU (unsigned)v dead */
  64#define CPU_POST_DEAD           0x0009 /* CPU (unsigned)v dead, cpu_hotplug
  65                                        * lock is dropped */
  66#define CPU_BROKEN              0x000B /* CPU (unsigned)v did not die properly,
  67                                        * perhaps due to preemption. */
  68
  69/* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
  70 * operation in progress
  71 */
  72#define CPU_TASKS_FROZEN        0x0010
  73
  74#define CPU_ONLINE_FROZEN       (CPU_ONLINE | CPU_TASKS_FROZEN)
  75#define CPU_UP_PREPARE_FROZEN   (CPU_UP_PREPARE | CPU_TASKS_FROZEN)
  76#define CPU_UP_CANCELED_FROZEN  (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
  77#define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
  78#define CPU_DOWN_FAILED_FROZEN  (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
  79#define CPU_DEAD_FROZEN         (CPU_DEAD | CPU_TASKS_FROZEN)
  80
  81#ifdef CONFIG_SMP
  82extern bool cpuhp_tasks_frozen;
  83int cpu_up(unsigned int cpu);
  84void notify_cpu_starting(unsigned int cpu);
  85extern void cpu_maps_update_begin(void);
  86extern void cpu_maps_update_done(void);
  87
  88#else   /* CONFIG_SMP */
  89#define cpuhp_tasks_frozen      0
  90
  91static inline void cpu_maps_update_begin(void)
  92{
  93}
  94
  95static inline void cpu_maps_update_done(void)
  96{
  97}
  98
  99#endif /* CONFIG_SMP */
 100extern struct bus_type cpu_subsys;
 101
 102#ifdef CONFIG_HOTPLUG_CPU
 103extern void cpus_write_lock(void);
 104extern void cpus_write_unlock(void);
 105extern void cpus_read_lock(void);
 106extern void cpus_read_unlock(void);
 107extern void lockdep_assert_cpus_held(void);
 108extern void cpu_hotplug_disable(void);
 109extern void cpu_hotplug_enable(void);
 110void clear_tasks_mm_cpumask(int cpu);
 111int cpu_down(unsigned int cpu);
 112
 113#else /* CONFIG_HOTPLUG_CPU */
 114
 115static inline void cpus_write_lock(void) { }
 116static inline void cpus_write_unlock(void) { }
 117static inline void cpus_read_lock(void) { }
 118static inline void cpus_read_unlock(void) { }
 119static inline void lockdep_assert_cpus_held(void) { }
 120static inline void cpu_hotplug_disable(void) { }
 121static inline void cpu_hotplug_enable(void) { }
 122#endif  /* !CONFIG_HOTPLUG_CPU */
 123
 124/* Wrappers which go away once all code is converted */
 125static inline void cpu_hotplug_begin(void) { cpus_write_lock(); }
 126static inline void cpu_hotplug_done(void) { cpus_write_unlock(); }
 127static inline void get_online_cpus(void) { cpus_read_lock(); }
 128static inline void put_online_cpus(void) { cpus_read_unlock(); }
 129
 130#ifdef CONFIG_PM_SLEEP_SMP
 131extern int freeze_secondary_cpus(int primary);
 132static inline int disable_nonboot_cpus(void)
 133{
 134        return freeze_secondary_cpus(0);
 135}
 136extern void enable_nonboot_cpus(void);
 137#else /* !CONFIG_PM_SLEEP_SMP */
 138static inline int disable_nonboot_cpus(void) { return 0; }
 139static inline void enable_nonboot_cpus(void) {}
 140#endif /* !CONFIG_PM_SLEEP_SMP */
 141
 142void cpu_startup_entry(enum cpuhp_state state);
 143
 144void cpu_idle_poll_ctrl(bool enable);
 145
 146/* Attach to any functions which should be considered cpuidle. */
 147#define __cpuidle       __attribute__((__section__(".cpuidle.text")))
 148
 149bool cpu_in_idle(unsigned long pc);
 150
 151void arch_cpu_idle(void);
 152void arch_cpu_idle_prepare(void);
 153void arch_cpu_idle_enter(void);
 154void arch_cpu_idle_exit(void);
 155void arch_cpu_idle_dead(void);
 156
 157int cpu_report_state(int cpu);
 158int cpu_check_up_prepare(int cpu);
 159void cpu_set_state_online(int cpu);
 160void play_idle(unsigned long duration_ms);
 161
 162#ifdef CONFIG_HOTPLUG_CPU
 163bool cpu_wait_death(unsigned int cpu, int seconds);
 164bool cpu_report_death(void);
 165void cpuhp_report_idle_dead(void);
 166#else
 167static inline void cpuhp_report_idle_dead(void) { }
 168#endif /* #ifdef CONFIG_HOTPLUG_CPU */
 169
 170#endif /* _LINUX_CPU_H_ */
 171