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 * and system devices are handled in drivers/base/sys.c. 10 * 11 * CPUs are exported via sysfs in the class/cpu/devices/ 12 * directory. 13 */ 14 #ifndef _LINUX_CPU_H_ 15 #define _LINUX_CPU_H_ 16 17 #include <linux/node.h> 18 #include <linux/compiler.h> 19 #include <linux/cpumask.h> 20 21 struct device; 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 33 extern int cpu_add_dev_attr(struct device_attribute *attr); 34 extern void cpu_remove_dev_attr(struct device_attribute *attr); 35 36 extern int cpu_add_dev_attr_group(struct attribute_group *attrs); 37 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs); 38 39 #ifdef CONFIG_HOTPLUG_CPU 40 extern void unregister_cpu(struct cpu *cpu); 41 extern ssize_t arch_cpu_probe(const char *, size_t); 42 extern ssize_t arch_cpu_release(const char *, size_t); 43 #endif 44 struct notifier_block; 45 46 #ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE 47 extern int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env); 48 extern ssize_t arch_print_cpu_modalias(struct device *dev, 49 struct device_attribute *attr, 50 char *bufptr); 51 #endif 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 /* prepare workqueues for other notifiers */ 77 CPU_PRI_WORKQUEUE = 5, 78 }; 79 80 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */ 81 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */ 82 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */ 83 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */ 84 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */ 85 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */ 86 #define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task, 87 * not handling interrupts, soon dead. 88 * Called on the dying cpu, interrupts 89 * are already disabled. Must not 90 * sleep, must not fail */ 91 #define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug 92 * lock is dropped */ 93 #define CPU_STARTING 0x000A /* CPU (unsigned)v soon running. 94 * Called on the new cpu, just before 95 * enabling interrupts. Must not sleep, 96 * must not fail */ 97 98 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend 99 * operation in progress 100 */ 101 #define CPU_TASKS_FROZEN 0x0010 102 103 #define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN) 104 #define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN) 105 #define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN) 106 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN) 107 #define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN) 108 #define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN) 109 #define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN) 110 #define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN) 111 112 113 #ifdef CONFIG_SMP 114 /* Need to know about CPUs going up/down? */ 115 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) 116 #define cpu_notifier(fn, pri) { \ 117 static struct notifier_block fn##_nb __cpuinitdata = \ 118 { .notifier_call = fn, .priority = pri }; \ 119 register_cpu_notifier(&fn##_nb); \ 120 } 121 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 122 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 123 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 124 #ifdef CONFIG_HOTPLUG_CPU 125 extern int register_cpu_notifier(struct notifier_block *nb); 126 extern void unregister_cpu_notifier(struct notifier_block *nb); 127 #else 128 129 #ifndef MODULE 130 extern int register_cpu_notifier(struct notifier_block *nb); 131 #else 132 static inline int register_cpu_notifier(struct notifier_block *nb) 133 { 134 return 0; 135 } 136 #endif 137 138 static inline void unregister_cpu_notifier(struct notifier_block *nb) 139 { 140 } 141 #endif 142 143 int cpu_up(unsigned int cpu); 144 void notify_cpu_starting(unsigned int cpu); 145 extern void cpu_maps_update_begin(void); 146 extern void cpu_maps_update_done(void); 147 148 #else /* CONFIG_SMP */ 149 150 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 151 152 static inline int register_cpu_notifier(struct notifier_block *nb) 153 { 154 return 0; 155 } 156 157 static inline void unregister_cpu_notifier(struct notifier_block *nb) 158 { 159 } 160 161 static inline void cpu_maps_update_begin(void) 162 { 163 } 164 165 static inline void cpu_maps_update_done(void) 166 { 167 } 168 169 #endif /* CONFIG_SMP */ 170 extern struct bus_type cpu_subsys; 171 172 #ifdef CONFIG_HOTPLUG_CPU 173 /* Stop CPUs going up and down. */ 174 175 extern void get_online_cpus(void); 176 extern void put_online_cpus(void); 177 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) 178 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) 179 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) 180 void clear_tasks_mm_cpumask(int cpu); 181 int cpu_down(unsigned int cpu); 182 183 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE 184 extern void cpu_hotplug_driver_lock(void); 185 extern void cpu_hotplug_driver_unlock(void); 186 #else 187 static inline void cpu_hotplug_driver_lock(void) 188 { 189 } 190 191 static inline void cpu_hotplug_driver_unlock(void) 192 { 193 } 194 #endif 195 196 #else /* CONFIG_HOTPLUG_CPU */ 197 198 #define get_online_cpus() do { } while (0) 199 #define put_online_cpus() do { } while (0) 200 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 201 /* These aren't inline functions due to a GCC bug. */ 202 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 203 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 204 #endif /* CONFIG_HOTPLUG_CPU */ 205 206 #ifdef CONFIG_PM_SLEEP_SMP 207 extern int disable_nonboot_cpus(void); 208 extern void enable_nonboot_cpus(void); 209 #else /* !CONFIG_PM_SLEEP_SMP */ 210 static inline int disable_nonboot_cpus(void) { return 0; } 211 static inline void enable_nonboot_cpus(void) {} 212 #endif /* !CONFIG_PM_SLEEP_SMP */ 213 214 #endif /* _LINUX_CPU_H_ */ 215