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 __printf(4, 5) 44struct device *cpu_device_create(struct device *parent, void *drvdata, 45 const struct attribute_group **groups, 46 const char *fmt, ...); 47#ifdef CONFIG_HOTPLUG_CPU 48extern void unregister_cpu(struct cpu *cpu); 49extern ssize_t arch_cpu_probe(const char *, size_t); 50extern ssize_t arch_cpu_release(const char *, size_t); 51#endif 52struct notifier_block; 53 54/* 55 * CPU notifier priorities. 56 */ 57enum { 58 /* 59 * SCHED_ACTIVE marks a cpu which is coming up active during 60 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first 61 * notifier. CPUSET_ACTIVE adjusts cpuset according to 62 * cpu_active mask right after SCHED_ACTIVE. During 63 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are 64 * ordered in the similar way. 65 * 66 * This ordering guarantees consistent cpu_active mask and 67 * migration behavior to all cpu notifiers. 68 */ 69 CPU_PRI_SCHED_ACTIVE = INT_MAX, 70 CPU_PRI_CPUSET_ACTIVE = INT_MAX - 1, 71 CPU_PRI_SCHED_INACTIVE = INT_MIN + 1, 72 CPU_PRI_CPUSET_INACTIVE = INT_MIN, 73 74 /* migration should happen before other stuff but after perf */ 75 CPU_PRI_PERF = 20, 76 CPU_PRI_MIGRATION = 10, 77 CPU_PRI_SMPBOOT = 9, 78 /* bring up workqueues before normal notifiers and down after */ 79 CPU_PRI_WORKQUEUE_UP = 5, 80 CPU_PRI_WORKQUEUE_DOWN = -5, 81}; 82 83#define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */ 84#define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */ 85#define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */ 86#define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */ 87#define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */ 88#define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */ 89#define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task, 90 * not handling interrupts, soon dead. 91 * Called on the dying cpu, interrupts 92 * are already disabled. Must not 93 * sleep, must not fail */ 94#define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug 95 * lock is dropped */ 96#define CPU_STARTING 0x000A /* CPU (unsigned)v soon running. 97 * Called on the new cpu, just before 98 * enabling interrupts. Must not sleep, 99 * must not fail */ 100#define CPU_DYING_IDLE 0x000B /* CPU (unsigned)v dying, reached 101 * idle loop. */ 102#define CPU_BROKEN 0x000C /* CPU (unsigned)v did not die properly, 103 * perhaps due to preemption. */ 104 105/* Used for CPU hotplug events occurring while tasks are frozen due to a suspend 106 * operation in progress 107 */ 108#define CPU_TASKS_FROZEN 0x0010 109 110#define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN) 111#define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN) 112#define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN) 113#define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN) 114#define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN) 115#define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN) 116#define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN) 117#define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN) 118 119 120#ifdef CONFIG_SMP 121/* Need to know about CPUs going up/down? */ 122#if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) 123#define cpu_notifier(fn, pri) { \ 124 static struct notifier_block fn##_nb = \ 125 { .notifier_call = fn, .priority = pri }; \ 126 register_cpu_notifier(&fn##_nb); \ 127} 128 129#define __cpu_notifier(fn, pri) { \ 130 static struct notifier_block fn##_nb = \ 131 { .notifier_call = fn, .priority = pri }; \ 132 __register_cpu_notifier(&fn##_nb); \ 133} 134#else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 135#define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 136#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 137#endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 138 139#ifdef CONFIG_HOTPLUG_CPU 140extern int register_cpu_notifier(struct notifier_block *nb); 141extern int __register_cpu_notifier(struct notifier_block *nb); 142extern void unregister_cpu_notifier(struct notifier_block *nb); 143extern void __unregister_cpu_notifier(struct notifier_block *nb); 144#else 145 146#ifndef MODULE 147extern int register_cpu_notifier(struct notifier_block *nb); 148extern int __register_cpu_notifier(struct notifier_block *nb); 149#else 150static inline int register_cpu_notifier(struct notifier_block *nb) 151{ 152 return 0; 153} 154 155static inline int __register_cpu_notifier(struct notifier_block *nb) 156{ 157 return 0; 158} 159#endif 160 161static inline void unregister_cpu_notifier(struct notifier_block *nb) 162{ 163} 164 165static inline void __unregister_cpu_notifier(struct notifier_block *nb) 166{ 167} 168#endif 169 170void smpboot_thread_init(void); 171int cpu_up(unsigned int cpu); 172void notify_cpu_starting(unsigned int cpu); 173extern void cpu_maps_update_begin(void); 174extern void cpu_maps_update_done(void); 175 176#define cpu_notifier_register_begin cpu_maps_update_begin 177#define cpu_notifier_register_done cpu_maps_update_done 178 179#else /* CONFIG_SMP */ 180 181#define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 182#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 183 184static inline int register_cpu_notifier(struct notifier_block *nb) 185{ 186 return 0; 187} 188 189static inline int __register_cpu_notifier(struct notifier_block *nb) 190{ 191 return 0; 192} 193 194static inline void unregister_cpu_notifier(struct notifier_block *nb) 195{ 196} 197 198static inline void __unregister_cpu_notifier(struct notifier_block *nb) 199{ 200} 201 202static inline void cpu_maps_update_begin(void) 203{ 204} 205 206static inline void cpu_maps_update_done(void) 207{ 208} 209 210static inline void cpu_notifier_register_begin(void) 211{ 212} 213 214static inline void cpu_notifier_register_done(void) 215{ 216} 217 218static inline void smpboot_thread_init(void) 219{ 220} 221 222#endif /* CONFIG_SMP */ 223extern struct bus_type cpu_subsys; 224 225#ifdef CONFIG_HOTPLUG_CPU 226/* Stop CPUs going up and down. */ 227 228extern void cpu_hotplug_begin(void); 229extern void cpu_hotplug_done(void); 230extern void 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 put_online_cpus() do { } while (0) 249#define cpu_hotplug_disable() do { } while (0) 250#define cpu_hotplug_enable() do { } while (0) 251#define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 252#define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 253/* These aren't inline functions due to a GCC bug. */ 254#define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 255#define __register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 256#define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 257#define __unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 258#endif /* CONFIG_HOTPLUG_CPU */ 259 260#ifdef CONFIG_PM_SLEEP_SMP 261extern int disable_nonboot_cpus(void); 262extern void enable_nonboot_cpus(void); 263#else /* !CONFIG_PM_SLEEP_SMP */ 264static inline int disable_nonboot_cpus(void) { return 0; } 265static inline void enable_nonboot_cpus(void) {} 266#endif /* !CONFIG_PM_SLEEP_SMP */ 267 268enum cpuhp_state { 269 CPUHP_OFFLINE, 270 CPUHP_ONLINE, 271}; 272 273void cpu_startup_entry(enum cpuhp_state state); 274 275void cpu_idle_poll_ctrl(bool enable); 276 277void arch_cpu_idle(void); 278void arch_cpu_idle_prepare(void); 279void arch_cpu_idle_enter(void); 280void arch_cpu_idle_exit(void); 281void arch_cpu_idle_dead(void); 282 283DECLARE_PER_CPU(bool, cpu_dead_idle); 284 285int cpu_report_state(int cpu); 286int cpu_check_up_prepare(int cpu); 287void cpu_set_state_online(int cpu); 288#ifdef CONFIG_HOTPLUG_CPU 289bool cpu_wait_death(unsigned int cpu, int seconds); 290bool cpu_report_death(void); 291#endif /* #ifdef CONFIG_HOTPLUG_CPU */ 292 293#endif /* _LINUX_CPU_H_ */ 294