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 __printf(4, 5) 44 struct device *cpu_device_create(struct device *parent, void *drvdata, 45 const struct attribute_group **groups, 46 const char *fmt, ...); 47 #ifdef CONFIG_HOTPLUG_CPU 48 extern void unregister_cpu(struct cpu *cpu); 49 extern ssize_t arch_cpu_probe(const char *, size_t); 50 extern ssize_t arch_cpu_release(const char *, size_t); 51 #endif 52 struct notifier_block; 53 54 /* 55 * CPU notifier priorities. 56 */ 57 enum { 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 140 extern int register_cpu_notifier(struct notifier_block *nb); 141 extern int __register_cpu_notifier(struct notifier_block *nb); 142 extern void unregister_cpu_notifier(struct notifier_block *nb); 143 extern void __unregister_cpu_notifier(struct notifier_block *nb); 144 #else 145 146 #ifndef MODULE 147 extern int register_cpu_notifier(struct notifier_block *nb); 148 extern int __register_cpu_notifier(struct notifier_block *nb); 149 #else 150 static inline int register_cpu_notifier(struct notifier_block *nb) 151 { 152 return 0; 153 } 154 155 static inline int __register_cpu_notifier(struct notifier_block *nb) 156 { 157 return 0; 158 } 159 #endif 160 161 static inline void unregister_cpu_notifier(struct notifier_block *nb) 162 { 163 } 164 165 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 166 { 167 } 168 #endif 169 170 void smpboot_thread_init(void); 171 int cpu_up(unsigned int cpu); 172 void notify_cpu_starting(unsigned int cpu); 173 extern void cpu_maps_update_begin(void); 174 extern 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) 183 184 static inline int register_cpu_notifier(struct notifier_block *nb) 185 { 186 return 0; 187 } 188 189 static inline int __register_cpu_notifier(struct notifier_block *nb) 190 { 191 return 0; 192 } 193 194 static inline void unregister_cpu_notifier(struct notifier_block *nb) 195 { 196 } 197 198 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 199 { 200 } 201 202 static inline void cpu_maps_update_begin(void) 203 { 204 } 205 206 static inline void cpu_maps_update_done(void) 207 { 208 } 209 210 static inline void cpu_notifier_register_begin(void) 211 { 212 } 213 214 static inline void cpu_notifier_register_done(void) 215 { 216 } 217 218 static inline void smpboot_thread_init(void) 219 { 220 } 221 222 #endif /* CONFIG_SMP */ 223 extern struct bus_type cpu_subsys; 224 225 #ifdef CONFIG_HOTPLUG_CPU 226 /* Stop CPUs going up and down. */ 227 228 extern void cpu_hotplug_begin(void); 229 extern void cpu_hotplug_done(void); 230 extern void get_online_cpus(void); 231 extern bool try_get_online_cpus(void); 232 extern void put_online_cpus(void); 233 extern void cpu_hotplug_disable(void); 234 extern void cpu_hotplug_enable(void); 235 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) 236 #define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri) 237 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) 238 #define __register_hotcpu_notifier(nb) __register_cpu_notifier(nb) 239 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) 240 #define __unregister_hotcpu_notifier(nb) __unregister_cpu_notifier(nb) 241 void clear_tasks_mm_cpumask(int cpu); 242 int cpu_down(unsigned int cpu); 243 244 #else /* CONFIG_HOTPLUG_CPU */ 245 246 static inline void cpu_hotplug_begin(void) {} 247 static inline void cpu_hotplug_done(void) {} 248 #define get_online_cpus() do { } while (0) 249 #define try_get_online_cpus() true 250 #define put_online_cpus() do { } while (0) 251 #define cpu_hotplug_disable() do { } while (0) 252 #define cpu_hotplug_enable() do { } while (0) 253 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 254 #define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 255 /* These aren't inline functions due to a GCC bug. */ 256 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 257 #define __register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 258 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 259 #define __unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 260 #endif /* CONFIG_HOTPLUG_CPU */ 261 262 #ifdef CONFIG_PM_SLEEP_SMP 263 extern int disable_nonboot_cpus(void); 264 extern void enable_nonboot_cpus(void); 265 #else /* !CONFIG_PM_SLEEP_SMP */ 266 static inline int disable_nonboot_cpus(void) { return 0; } 267 static inline void enable_nonboot_cpus(void) {} 268 #endif /* !CONFIG_PM_SLEEP_SMP */ 269 270 enum cpuhp_state { 271 CPUHP_OFFLINE, 272 CPUHP_ONLINE, 273 }; 274 275 void cpu_startup_entry(enum cpuhp_state state); 276 277 void cpu_idle_poll_ctrl(bool enable); 278 279 void arch_cpu_idle(void); 280 void arch_cpu_idle_prepare(void); 281 void arch_cpu_idle_enter(void); 282 void arch_cpu_idle_exit(void); 283 void arch_cpu_idle_dead(void); 284 285 DECLARE_PER_CPU(bool, cpu_dead_idle); 286 287 int cpu_report_state(int cpu); 288 int cpu_check_up_prepare(int cpu); 289 void cpu_set_state_online(int cpu); 290 #ifdef CONFIG_HOTPLUG_CPU 291 bool cpu_wait_death(unsigned int cpu, int seconds); 292 bool cpu_report_death(void); 293 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 294 295 #endif /* _LINUX_CPU_H_ */ 296