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 20struct device; 21struct device_node; 22struct attribute_group; 23 24struct cpu { 25 int node_id; /* The node which contains the CPU */ 26 int hotpluggable; /* creates sysfs control file if hotpluggable */ 27 struct device dev; 28}; 29 30extern int register_cpu(struct cpu *cpu, int num); 31extern struct device *get_cpu_device(unsigned cpu); 32extern bool cpu_is_hotpluggable(unsigned cpu); 33extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id); 34extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, 35 int cpu, unsigned int *thread); 36 37extern int cpu_add_dev_attr(struct device_attribute *attr); 38extern void cpu_remove_dev_attr(struct device_attribute *attr); 39 40extern int cpu_add_dev_attr_group(struct attribute_group *attrs); 41extern void cpu_remove_dev_attr_group(struct attribute_group *attrs); 42 43extern struct device *cpu_device_create(struct device *parent, void *drvdata, 44 const struct attribute_group **groups, 45 const char *fmt, ...); 46#ifdef CONFIG_HOTPLUG_CPU 47extern void unregister_cpu(struct cpu *cpu); 48extern ssize_t arch_cpu_probe(const char *, size_t); 49extern ssize_t arch_cpu_release(const char *, size_t); 50#endif 51struct notifier_block; 52 53/* 54 * CPU notifier priorities. 55 */ 56enum { 57 /* 58 * SCHED_ACTIVE marks a cpu which is coming up active during 59 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first 60 * notifier. CPUSET_ACTIVE adjusts cpuset according to 61 * cpu_active mask right after SCHED_ACTIVE. During 62 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are 63 * ordered in the similar way. 64 * 65 * This ordering guarantees consistent cpu_active mask and 66 * migration behavior to all cpu notifiers. 67 */ 68 CPU_PRI_SCHED_ACTIVE = INT_MAX, 69 CPU_PRI_CPUSET_ACTIVE = INT_MAX - 1, 70 CPU_PRI_SCHED_INACTIVE = INT_MIN + 1, 71 CPU_PRI_CPUSET_INACTIVE = INT_MIN, 72 73 /* migration should happen before other stuff but after perf */ 74 CPU_PRI_PERF = 20, 75 CPU_PRI_MIGRATION = 10, 76 CPU_PRI_SMPBOOT = 9, 77 /* bring up workqueues before normal notifiers and down after */ 78 CPU_PRI_WORKQUEUE_UP = 5, 79 CPU_PRI_WORKQUEUE_DOWN = -5, 80}; 81 82#define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */ 83#define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */ 84#define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */ 85#define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */ 86#define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */ 87#define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */ 88#define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task, 89 * not handling interrupts, soon dead. 90 * Called on the dying cpu, interrupts 91 * are already disabled. Must not 92 * sleep, must not fail */ 93#define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug 94 * lock is dropped */ 95#define CPU_STARTING 0x000A /* CPU (unsigned)v soon running. 96 * Called on the new cpu, just before 97 * enabling interrupts. Must not sleep, 98 * must not fail */ 99#define CPU_DYING_IDLE 0x000B /* CPU (unsigned)v dying, reached 100 * idle loop. */ 101#define CPU_BROKEN 0x000C /* CPU (unsigned)v did not die properly, 102 * perhaps due to preemption. */ 103 104/* Used for CPU hotplug events occurring while tasks are frozen due to a suspend 105 * operation in progress 106 */ 107#define CPU_TASKS_FROZEN 0x0010 108 109#define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN) 110#define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN) 111#define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN) 112#define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN) 113#define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN) 114#define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN) 115#define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN) 116#define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN) 117 118 119#ifdef CONFIG_SMP 120/* Need to know about CPUs going up/down? */ 121#if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) 122#define cpu_notifier(fn, pri) { \ 123 static struct notifier_block fn##_nb = \ 124 { .notifier_call = fn, .priority = pri }; \ 125 register_cpu_notifier(&fn##_nb); \ 126} 127 128#define __cpu_notifier(fn, pri) { \ 129 static struct notifier_block fn##_nb = \ 130 { .notifier_call = fn, .priority = pri }; \ 131 __register_cpu_notifier(&fn##_nb); \ 132} 133#else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 134#define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 135#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 136#endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 137 138#ifdef CONFIG_HOTPLUG_CPU 139extern int register_cpu_notifier(struct notifier_block *nb); 140extern int __register_cpu_notifier(struct notifier_block *nb); 141extern void unregister_cpu_notifier(struct notifier_block *nb); 142extern void __unregister_cpu_notifier(struct notifier_block *nb); 143#else 144 145#ifndef MODULE 146extern int register_cpu_notifier(struct notifier_block *nb); 147extern int __register_cpu_notifier(struct notifier_block *nb); 148#else 149static inline int register_cpu_notifier(struct notifier_block *nb) 150{ 151 return 0; 152} 153 154static inline int __register_cpu_notifier(struct notifier_block *nb) 155{ 156 return 0; 157} 158#endif 159 160static inline void unregister_cpu_notifier(struct notifier_block *nb) 161{ 162} 163 164static inline void __unregister_cpu_notifier(struct notifier_block *nb) 165{ 166} 167#endif 168 169void smpboot_thread_init(void); 170int cpu_up(unsigned int cpu); 171void notify_cpu_starting(unsigned int cpu); 172extern void cpu_maps_update_begin(void); 173extern void cpu_maps_update_done(void); 174 175#define cpu_notifier_register_begin cpu_maps_update_begin 176#define cpu_notifier_register_done cpu_maps_update_done 177 178#else /* CONFIG_SMP */ 179 180#define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 181#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 182 183static inline int register_cpu_notifier(struct notifier_block *nb) 184{ 185 return 0; 186} 187 188static inline int __register_cpu_notifier(struct notifier_block *nb) 189{ 190 return 0; 191} 192 193static inline void unregister_cpu_notifier(struct notifier_block *nb) 194{ 195} 196 197static inline void __unregister_cpu_notifier(struct notifier_block *nb) 198{ 199} 200 201static inline void cpu_maps_update_begin(void) 202{ 203} 204 205static inline void cpu_maps_update_done(void) 206{ 207} 208 209static inline void cpu_notifier_register_begin(void) 210{ 211} 212 213static inline void cpu_notifier_register_done(void) 214{ 215} 216 217static inline void smpboot_thread_init(void) 218{ 219} 220 221#endif /* CONFIG_SMP */ 222extern struct bus_type cpu_subsys; 223 224#ifdef CONFIG_HOTPLUG_CPU 225/* Stop CPUs going up and down. */ 226 227extern void cpu_hotplug_begin(void); 228extern void cpu_hotplug_done(void); 229extern void get_online_cpus(void); 230extern bool try_get_online_cpus(void); 231extern void put_online_cpus(void); 232extern void cpu_hotplug_disable(void); 233extern void cpu_hotplug_enable(void); 234#define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) 235#define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri) 236#define register_hotcpu_notifier(nb) register_cpu_notifier(nb) 237#define __register_hotcpu_notifier(nb) __register_cpu_notifier(nb) 238#define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) 239#define __unregister_hotcpu_notifier(nb) __unregister_cpu_notifier(nb) 240void clear_tasks_mm_cpumask(int cpu); 241int cpu_down(unsigned int cpu); 242 243#else /* CONFIG_HOTPLUG_CPU */ 244 245static inline void cpu_hotplug_begin(void) {} 246static inline void cpu_hotplug_done(void) {} 247#define get_online_cpus() do { } while (0) 248#define try_get_online_cpus() true 249#define put_online_cpus() do { } while (0) 250#define cpu_hotplug_disable() do { } while (0) 251#define cpu_hotplug_enable() do { } while (0) 252#define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 253#define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 254/* These aren't inline functions due to a GCC bug. */ 255#define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 256#define __register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 257#define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 258#define __unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 259#endif /* CONFIG_HOTPLUG_CPU */ 260 261#ifdef CONFIG_PM_SLEEP_SMP 262extern int disable_nonboot_cpus(void); 263extern void enable_nonboot_cpus(void); 264#else /* !CONFIG_PM_SLEEP_SMP */ 265static inline int disable_nonboot_cpus(void) { return 0; } 266static inline void enable_nonboot_cpus(void) {} 267#endif /* !CONFIG_PM_SLEEP_SMP */ 268 269enum cpuhp_state { 270 CPUHP_OFFLINE, 271 CPUHP_ONLINE, 272}; 273 274void cpu_startup_entry(enum cpuhp_state state); 275 276void cpu_idle_poll_ctrl(bool enable); 277 278void arch_cpu_idle(void); 279void arch_cpu_idle_prepare(void); 280void arch_cpu_idle_enter(void); 281void arch_cpu_idle_exit(void); 282void arch_cpu_idle_dead(void); 283 284DECLARE_PER_CPU(bool, cpu_dead_idle); 285 286int cpu_report_state(int cpu); 287int cpu_check_up_prepare(int cpu); 288void cpu_set_state_online(int cpu); 289#ifdef CONFIG_HOTPLUG_CPU 290bool cpu_wait_death(unsigned int cpu, int seconds); 291bool cpu_report_death(void); 292#endif /* #ifdef CONFIG_HOTPLUG_CPU */ 293 294#endif /* _LINUX_CPU_H_ */ 295