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 #include <linux/cpuhotplug.h> 20 21 struct device; 22 struct device_node; 23 struct attribute_group; 24 25 struct cpu { 26 int node_id; /* The node which contains the CPU */ 27 int hotpluggable; /* creates sysfs control file if hotpluggable */ 28 struct device dev; 29 }; 30 31 extern void boot_cpu_init(void); 32 extern void boot_cpu_state_init(void); 33 34 extern int register_cpu(struct cpu *cpu, int num); 35 extern struct device *get_cpu_device(unsigned cpu); 36 extern bool cpu_is_hotpluggable(unsigned cpu); 37 extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id); 38 extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, 39 int cpu, unsigned int *thread); 40 41 extern int cpu_add_dev_attr(struct device_attribute *attr); 42 extern void cpu_remove_dev_attr(struct device_attribute *attr); 43 44 extern int cpu_add_dev_attr_group(struct attribute_group *attrs); 45 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs); 46 47 extern __printf(4, 5) 48 struct device *cpu_device_create(struct device *parent, void *drvdata, 49 const struct attribute_group **groups, 50 const char *fmt, ...); 51 #ifdef CONFIG_HOTPLUG_CPU 52 extern void unregister_cpu(struct cpu *cpu); 53 extern ssize_t arch_cpu_probe(const char *, size_t); 54 extern ssize_t arch_cpu_release(const char *, size_t); 55 #endif 56 struct notifier_block; 57 58 /* 59 * CPU notifier priorities. 60 */ 61 enum { 62 /* 63 * SCHED_ACTIVE marks a cpu which is coming up active during 64 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first 65 * notifier. CPUSET_ACTIVE adjusts cpuset according to 66 * cpu_active mask right after SCHED_ACTIVE. During 67 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are 68 * ordered in the similar way. 69 * 70 * This ordering guarantees consistent cpu_active mask and 71 * migration behavior to all cpu notifiers. 72 */ 73 CPU_PRI_SCHED_ACTIVE = INT_MAX, 74 CPU_PRI_CPUSET_ACTIVE = INT_MAX - 1, 75 CPU_PRI_SCHED_INACTIVE = INT_MIN + 1, 76 CPU_PRI_CPUSET_INACTIVE = INT_MIN, 77 78 /* migration should happen before other stuff but after perf */ 79 CPU_PRI_PERF = 20, 80 CPU_PRI_MIGRATION = 10, 81 82 /* bring up workqueues before normal notifiers and down after */ 83 CPU_PRI_WORKQUEUE_UP = 5, 84 CPU_PRI_WORKQUEUE_DOWN = -5, 85 }; 86 87 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */ 88 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */ 89 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */ 90 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */ 91 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */ 92 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */ 93 #define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task, 94 * not handling interrupts, soon dead. 95 * Called on the dying cpu, interrupts 96 * are already disabled. Must not 97 * sleep, must not fail */ 98 #define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug 99 * lock is dropped */ 100 #define CPU_STARTING 0x000A /* CPU (unsigned)v soon running. 101 * Called on the new cpu, just before 102 * enabling interrupts. Must not sleep, 103 * must not fail */ 104 #define CPU_BROKEN 0x000B /* CPU (unsigned)v did not die properly, 105 * perhaps due to preemption. */ 106 107 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend 108 * operation in progress 109 */ 110 #define CPU_TASKS_FROZEN 0x0010 111 112 #define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN) 113 #define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN) 114 #define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN) 115 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN) 116 #define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN) 117 #define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN) 118 #define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN) 119 #define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN) 120 121 122 #ifdef CONFIG_SMP 123 extern bool cpuhp_tasks_frozen; 124 /* Need to know about CPUs going up/down? */ 125 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) 126 #define cpu_notifier(fn, pri) { \ 127 static struct notifier_block fn##_nb = \ 128 { .notifier_call = fn, .priority = pri }; \ 129 register_cpu_notifier(&fn##_nb); \ 130 } 131 132 #define __cpu_notifier(fn, pri) { \ 133 static struct notifier_block fn##_nb = \ 134 { .notifier_call = fn, .priority = pri }; \ 135 __register_cpu_notifier(&fn##_nb); \ 136 } 137 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 138 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 139 #define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 140 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 141 142 #ifdef CONFIG_HOTPLUG_CPU 143 extern int register_cpu_notifier(struct notifier_block *nb); 144 extern int __register_cpu_notifier(struct notifier_block *nb); 145 extern void unregister_cpu_notifier(struct notifier_block *nb); 146 extern void __unregister_cpu_notifier(struct notifier_block *nb); 147 #else 148 149 #ifndef MODULE 150 extern int register_cpu_notifier(struct notifier_block *nb); 151 extern int __register_cpu_notifier(struct notifier_block *nb); 152 #else 153 static inline int register_cpu_notifier(struct notifier_block *nb) 154 { 155 return 0; 156 } 157 158 static inline int __register_cpu_notifier(struct notifier_block *nb) 159 { 160 return 0; 161 } 162 #endif 163 164 static inline void unregister_cpu_notifier(struct notifier_block *nb) 165 { 166 } 167 168 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 169 { 170 } 171 #endif 172 173 int cpu_up(unsigned int cpu); 174 void notify_cpu_starting(unsigned int cpu); 175 extern void cpu_maps_update_begin(void); 176 extern void cpu_maps_update_done(void); 177 178 #define cpu_notifier_register_begin cpu_maps_update_begin 179 #define cpu_notifier_register_done cpu_maps_update_done 180 181 #else /* CONFIG_SMP */ 182 #define cpuhp_tasks_frozen 0 183 184 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 185 #define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 186 187 static inline int register_cpu_notifier(struct notifier_block *nb) 188 { 189 return 0; 190 } 191 192 static inline int __register_cpu_notifier(struct notifier_block *nb) 193 { 194 return 0; 195 } 196 197 static inline void unregister_cpu_notifier(struct notifier_block *nb) 198 { 199 } 200 201 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 202 { 203 } 204 205 static inline void cpu_maps_update_begin(void) 206 { 207 } 208 209 static inline void cpu_maps_update_done(void) 210 { 211 } 212 213 static inline void cpu_notifier_register_begin(void) 214 { 215 } 216 217 static inline void cpu_notifier_register_done(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 void put_online_cpus(void); 231 extern void cpu_hotplug_disable(void); 232 extern void cpu_hotplug_enable(void); 233 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) 234 #define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri) 235 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) 236 #define __register_hotcpu_notifier(nb) __register_cpu_notifier(nb) 237 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) 238 #define __unregister_hotcpu_notifier(nb) __unregister_cpu_notifier(nb) 239 void clear_tasks_mm_cpumask(int cpu); 240 int cpu_down(unsigned int cpu); 241 242 #else /* CONFIG_HOTPLUG_CPU */ 243 244 static inline void cpu_hotplug_begin(void) {} 245 static inline void cpu_hotplug_done(void) {} 246 #define get_online_cpus() do { } while (0) 247 #define put_online_cpus() do { } while (0) 248 #define cpu_hotplug_disable() do { } while (0) 249 #define cpu_hotplug_enable() do { } while (0) 250 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 251 #define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 252 /* These aren't inline functions due to a GCC bug. */ 253 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 254 #define __register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 255 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 256 #define __unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 257 #endif /* CONFIG_HOTPLUG_CPU */ 258 259 #ifdef CONFIG_PM_SLEEP_SMP 260 extern int disable_nonboot_cpus(void); 261 extern void enable_nonboot_cpus(void); 262 #else /* !CONFIG_PM_SLEEP_SMP */ 263 static inline int disable_nonboot_cpus(void) { return 0; } 264 static inline void enable_nonboot_cpus(void) {} 265 #endif /* !CONFIG_PM_SLEEP_SMP */ 266 267 void cpu_startup_entry(enum cpuhp_state state); 268 269 void cpu_idle_poll_ctrl(bool enable); 270 271 void arch_cpu_idle(void); 272 void arch_cpu_idle_prepare(void); 273 void arch_cpu_idle_enter(void); 274 void arch_cpu_idle_exit(void); 275 void arch_cpu_idle_dead(void); 276 277 int cpu_report_state(int cpu); 278 int cpu_check_up_prepare(int cpu); 279 void cpu_set_state_online(int cpu); 280 #ifdef CONFIG_HOTPLUG_CPU 281 bool cpu_wait_death(unsigned int cpu, int seconds); 282 bool cpu_report_death(void); 283 void cpuhp_report_idle_dead(void); 284 #else 285 static inline void cpuhp_report_idle_dead(void) { } 286 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 287 288 #endif /* _LINUX_CPU_H_ */ 289