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