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 20 struct device; 21 struct device_node; 22 struct attribute_group; 23 24 struct 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 30 extern int register_cpu(struct cpu *cpu, int num); 31 extern struct device *get_cpu_device(unsigned cpu); 32 extern bool cpu_is_hotpluggable(unsigned cpu); 33 extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id); 34 extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, 35 int cpu, unsigned int *thread); 36 37 extern int cpu_add_dev_attr(struct device_attribute *attr); 38 extern void cpu_remove_dev_attr(struct device_attribute *attr); 39 40 extern int cpu_add_dev_attr_group(struct attribute_group *attrs); 41 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs); 42 43 extern 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 47 extern void unregister_cpu(struct cpu *cpu); 48 extern ssize_t arch_cpu_probe(const char *, size_t); 49 extern ssize_t arch_cpu_release(const char *, size_t); 50 #endif 51 struct notifier_block; 52 53 /* 54 * CPU notifier priorities. 55 */ 56 enum { 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 139 extern int register_cpu_notifier(struct notifier_block *nb); 140 extern int __register_cpu_notifier(struct notifier_block *nb); 141 extern void unregister_cpu_notifier(struct notifier_block *nb); 142 extern void __unregister_cpu_notifier(struct notifier_block *nb); 143 #else 144 145 #ifndef MODULE 146 extern int register_cpu_notifier(struct notifier_block *nb); 147 extern int __register_cpu_notifier(struct notifier_block *nb); 148 #else 149 static inline int register_cpu_notifier(struct notifier_block *nb) 150 { 151 return 0; 152 } 153 154 static inline int __register_cpu_notifier(struct notifier_block *nb) 155 { 156 return 0; 157 } 158 #endif 159 160 static inline void unregister_cpu_notifier(struct notifier_block *nb) 161 { 162 } 163 164 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 165 { 166 } 167 #endif 168 169 void smpboot_thread_init(void); 170 int cpu_up(unsigned int cpu); 171 void notify_cpu_starting(unsigned int cpu); 172 extern void cpu_maps_update_begin(void); 173 extern 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) 182 183 static inline int register_cpu_notifier(struct notifier_block *nb) 184 { 185 return 0; 186 } 187 188 static inline int __register_cpu_notifier(struct notifier_block *nb) 189 { 190 return 0; 191 } 192 193 static inline void unregister_cpu_notifier(struct notifier_block *nb) 194 { 195 } 196 197 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 198 { 199 } 200 201 static inline void cpu_maps_update_begin(void) 202 { 203 } 204 205 static inline void cpu_maps_update_done(void) 206 { 207 } 208 209 static inline void cpu_notifier_register_begin(void) 210 { 211 } 212 213 static inline void cpu_notifier_register_done(void) 214 { 215 } 216 217 static inline void smpboot_thread_init(void) 218 { 219 } 220 221 #endif /* CONFIG_SMP */ 222 extern struct bus_type cpu_subsys; 223 224 #ifdef CONFIG_HOTPLUG_CPU 225 /* Stop CPUs going up and down. */ 226 227 extern void cpu_hotplug_begin(void); 228 extern void cpu_hotplug_done(void); 229 extern void get_online_cpus(void); 230 extern bool try_get_online_cpus(void); 231 extern void put_online_cpus(void); 232 extern void cpu_hotplug_disable(void); 233 extern 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) 240 void clear_tasks_mm_cpumask(int cpu); 241 int cpu_down(unsigned int cpu); 242 243 #else /* CONFIG_HOTPLUG_CPU */ 244 245 static inline void cpu_hotplug_begin(void) {} 246 static 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 262 extern int disable_nonboot_cpus(void); 263 extern void enable_nonboot_cpus(void); 264 #else /* !CONFIG_PM_SLEEP_SMP */ 265 static inline int disable_nonboot_cpus(void) { return 0; } 266 static inline void enable_nonboot_cpus(void) {} 267 #endif /* !CONFIG_PM_SLEEP_SMP */ 268 269 enum cpuhp_state { 270 CPUHP_OFFLINE, 271 CPUHP_ONLINE, 272 }; 273 274 void cpu_startup_entry(enum cpuhp_state state); 275 276 void cpu_idle_poll_ctrl(bool enable); 277 278 void arch_cpu_idle(void); 279 void arch_cpu_idle_prepare(void); 280 void arch_cpu_idle_enter(void); 281 void arch_cpu_idle_exit(void); 282 void arch_cpu_idle_dead(void); 283 284 DECLARE_PER_CPU(bool, cpu_dead_idle); 285 286 int cpu_report_state(int cpu); 287 int cpu_check_up_prepare(int cpu); 288 void cpu_set_state_online(int cpu); 289 #ifdef CONFIG_HOTPLUG_CPU 290 bool cpu_wait_death(unsigned int cpu, int seconds); 291 bool cpu_report_death(void); 292 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 293 294 #endif /* _LINUX_CPU_H_ */ 295