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 /* bring up workqueues before normal notifiers and down after */ 77 CPU_PRI_WORKQUEUE_UP = 5, 78 CPU_PRI_WORKQUEUE_DOWN = -5, 79 }; 80 81 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */ 82 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */ 83 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */ 84 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */ 85 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */ 86 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */ 87 #define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task, 88 * not handling interrupts, soon dead. 89 * Called on the dying cpu, interrupts 90 * are already disabled. Must not 91 * sleep, must not fail */ 92 #define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug 93 * lock is dropped */ 94 #define CPU_STARTING 0x000A /* CPU (unsigned)v soon running. 95 * Called on the new cpu, just before 96 * enabling interrupts. Must not sleep, 97 * must not fail */ 98 99 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend 100 * operation in progress 101 */ 102 #define CPU_TASKS_FROZEN 0x0010 103 104 #define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN) 105 #define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN) 106 #define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN) 107 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN) 108 #define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN) 109 #define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN) 110 #define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN) 111 #define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN) 112 113 114 #ifdef CONFIG_SMP 115 /* Need to know about CPUs going up/down? */ 116 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) 117 #define cpu_notifier(fn, pri) { \ 118 static struct notifier_block fn##_nb = \ 119 { .notifier_call = fn, .priority = pri }; \ 120 register_cpu_notifier(&fn##_nb); \ 121 } 122 123 #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 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 129 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 130 #define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 131 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 132 133 #ifdef CONFIG_HOTPLUG_CPU 134 extern int register_cpu_notifier(struct notifier_block *nb); 135 extern int __register_cpu_notifier(struct notifier_block *nb); 136 extern void unregister_cpu_notifier(struct notifier_block *nb); 137 extern void __unregister_cpu_notifier(struct notifier_block *nb); 138 #else 139 140 #ifndef MODULE 141 extern int register_cpu_notifier(struct notifier_block *nb); 142 extern int __register_cpu_notifier(struct notifier_block *nb); 143 #else 144 static inline int register_cpu_notifier(struct notifier_block *nb) 145 { 146 return 0; 147 } 148 149 static inline int __register_cpu_notifier(struct notifier_block *nb) 150 { 151 return 0; 152 } 153 #endif 154 155 static inline void unregister_cpu_notifier(struct notifier_block *nb) 156 { 157 } 158 159 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 160 { 161 } 162 #endif 163 164 int cpu_up(unsigned int cpu); 165 void notify_cpu_starting(unsigned int cpu); 166 extern void cpu_maps_update_begin(void); 167 extern void cpu_maps_update_done(void); 168 169 #define cpu_notifier_register_begin cpu_maps_update_begin 170 #define cpu_notifier_register_done cpu_maps_update_done 171 172 #else /* CONFIG_SMP */ 173 174 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 175 #define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) 176 177 static inline int register_cpu_notifier(struct notifier_block *nb) 178 { 179 return 0; 180 } 181 182 static inline int __register_cpu_notifier(struct notifier_block *nb) 183 { 184 return 0; 185 } 186 187 static inline void unregister_cpu_notifier(struct notifier_block *nb) 188 { 189 } 190 191 static inline void __unregister_cpu_notifier(struct notifier_block *nb) 192 { 193 } 194 195 static inline void cpu_maps_update_begin(void) 196 { 197 } 198 199 static inline void cpu_maps_update_done(void) 200 { 201 } 202 203 static inline void cpu_notifier_register_begin(void) 204 { 205 } 206 207 static inline void cpu_notifier_register_done(void) 208 { 209 } 210 211 #endif /* CONFIG_SMP */ 212 extern struct bus_type cpu_subsys; 213 214 #ifdef CONFIG_HOTPLUG_CPU 215 /* Stop CPUs going up and down. */ 216 217 extern void cpu_hotplug_begin(void); 218 extern void cpu_hotplug_done(void); 219 extern void get_online_cpus(void); 220 extern bool try_get_online_cpus(void); 221 extern void put_online_cpus(void); 222 extern void cpu_hotplug_disable(void); 223 extern void cpu_hotplug_enable(void); 224 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) 225 #define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri) 226 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) 227 #define __register_hotcpu_notifier(nb) __register_cpu_notifier(nb) 228 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) 229 #define __unregister_hotcpu_notifier(nb) __unregister_cpu_notifier(nb) 230 void clear_tasks_mm_cpumask(int cpu); 231 int cpu_down(unsigned int cpu); 232 233 #else /* CONFIG_HOTPLUG_CPU */ 234 235 static inline void cpu_hotplug_begin(void) {} 236 static inline void cpu_hotplug_done(void) {} 237 #define get_online_cpus() do { } while (0) 238 #define try_get_online_cpus() true 239 #define put_online_cpus() do { } while (0) 240 #define cpu_hotplug_disable() do { } while (0) 241 #define cpu_hotplug_enable() do { } while (0) 242 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 243 #define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 244 /* These aren't inline functions due to a GCC bug. */ 245 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 246 #define __register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 247 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 248 #define __unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 249 #endif /* CONFIG_HOTPLUG_CPU */ 250 251 #ifdef CONFIG_PM_SLEEP_SMP 252 extern int disable_nonboot_cpus(void); 253 extern void enable_nonboot_cpus(void); 254 #else /* !CONFIG_PM_SLEEP_SMP */ 255 static inline int disable_nonboot_cpus(void) { return 0; } 256 static inline void enable_nonboot_cpus(void) {} 257 #endif /* !CONFIG_PM_SLEEP_SMP */ 258 259 enum cpuhp_state { 260 CPUHP_OFFLINE, 261 CPUHP_ONLINE, 262 }; 263 264 void cpu_startup_entry(enum cpuhp_state state); 265 266 void cpu_idle_poll_ctrl(bool enable); 267 268 void arch_cpu_idle(void); 269 void arch_cpu_idle_prepare(void); 270 void arch_cpu_idle_enter(void); 271 void arch_cpu_idle_exit(void); 272 void arch_cpu_idle_dead(void); 273 274 #endif /* _LINUX_CPU_H_ */ 275