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/sysdev.h> 18 #include <linux/node.h> 19 #include <linux/compiler.h> 20 #include <linux/cpumask.h> 21 22 struct cpu { 23 int node_id; /* The node which contains the CPU */ 24 int hotpluggable; /* creates sysfs control file if hotpluggable */ 25 struct sys_device sysdev; 26 }; 27 28 extern int register_cpu(struct cpu *cpu, int num); 29 extern struct sys_device *get_cpu_sysdev(unsigned cpu); 30 31 extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr); 32 extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr); 33 34 extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs); 35 extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs); 36 37 extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls); 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 /* 47 * CPU notifier priorities. 48 */ 49 enum { 50 /* 51 * SCHED_ACTIVE marks a cpu which is coming up active during 52 * CPU_ONLINE and CPU_DOWN_FAILED and must be the first 53 * notifier. CPUSET_ACTIVE adjusts cpuset according to 54 * cpu_active mask right after SCHED_ACTIVE. During 55 * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are 56 * ordered in the similar way. 57 * 58 * This ordering guarantees consistent cpu_active mask and 59 * migration behavior to all cpu notifiers. 60 */ 61 CPU_PRI_SCHED_ACTIVE = INT_MAX, 62 CPU_PRI_CPUSET_ACTIVE = INT_MAX - 1, 63 CPU_PRI_SCHED_INACTIVE = INT_MIN + 1, 64 CPU_PRI_CPUSET_INACTIVE = INT_MIN, 65 66 /* migration should happen before other stuff but after perf */ 67 CPU_PRI_PERF = 20, 68 CPU_PRI_MIGRATION = 10, 69 /* prepare workqueues for other notifiers */ 70 CPU_PRI_WORKQUEUE = 5, 71 }; 72 73 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */ 74 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */ 75 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */ 76 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */ 77 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */ 78 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */ 79 #define CPU_DYING 0x0008 /* CPU (unsigned)v not running any task, 80 * not handling interrupts, soon dead. 81 * Called on the dying cpu, interrupts 82 * are already disabled. Must not 83 * sleep, must not fail */ 84 #define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug 85 * lock is dropped */ 86 #define CPU_STARTING 0x000A /* CPU (unsigned)v soon running. 87 * Called on the new cpu, just before 88 * enabling interrupts. Must not sleep, 89 * must not fail */ 90 91 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend 92 * operation in progress 93 */ 94 #define CPU_TASKS_FROZEN 0x0010 95 96 #define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN) 97 #define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN) 98 #define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN) 99 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN) 100 #define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN) 101 #define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN) 102 #define CPU_DYING_FROZEN (CPU_DYING | CPU_TASKS_FROZEN) 103 #define CPU_STARTING_FROZEN (CPU_STARTING | CPU_TASKS_FROZEN) 104 105 106 #ifdef CONFIG_SMP 107 /* Need to know about CPUs going up/down? */ 108 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) 109 #define cpu_notifier(fn, pri) { \ 110 static struct notifier_block fn##_nb __cpuinitdata = \ 111 { .notifier_call = fn, .priority = pri }; \ 112 register_cpu_notifier(&fn##_nb); \ 113 } 114 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 115 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 116 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ 117 #ifdef CONFIG_HOTPLUG_CPU 118 extern int register_cpu_notifier(struct notifier_block *nb); 119 extern void unregister_cpu_notifier(struct notifier_block *nb); 120 #else 121 122 #ifndef MODULE 123 extern int register_cpu_notifier(struct notifier_block *nb); 124 #else 125 static inline int register_cpu_notifier(struct notifier_block *nb) 126 { 127 return 0; 128 } 129 #endif 130 131 static inline void unregister_cpu_notifier(struct notifier_block *nb) 132 { 133 } 134 #endif 135 136 int cpu_up(unsigned int cpu); 137 void notify_cpu_starting(unsigned int cpu); 138 extern void cpu_maps_update_begin(void); 139 extern void cpu_maps_update_done(void); 140 141 #else /* CONFIG_SMP */ 142 143 #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) 144 145 static inline int register_cpu_notifier(struct notifier_block *nb) 146 { 147 return 0; 148 } 149 150 static inline void unregister_cpu_notifier(struct notifier_block *nb) 151 { 152 } 153 154 static inline void cpu_maps_update_begin(void) 155 { 156 } 157 158 static inline void cpu_maps_update_done(void) 159 { 160 } 161 162 #endif /* CONFIG_SMP */ 163 extern struct sysdev_class cpu_sysdev_class; 164 165 #ifdef CONFIG_HOTPLUG_CPU 166 /* Stop CPUs going up and down. */ 167 168 extern void get_online_cpus(void); 169 extern void put_online_cpus(void); 170 #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) 171 #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) 172 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) 173 int cpu_down(unsigned int cpu); 174 175 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE 176 extern void cpu_hotplug_driver_lock(void); 177 extern void cpu_hotplug_driver_unlock(void); 178 #else 179 static inline void cpu_hotplug_driver_lock(void) 180 { 181 } 182 183 static inline void cpu_hotplug_driver_unlock(void) 184 { 185 } 186 #endif 187 188 #else /* CONFIG_HOTPLUG_CPU */ 189 190 #define get_online_cpus() do { } while (0) 191 #define put_online_cpus() do { } while (0) 192 #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) 193 /* These aren't inline functions due to a GCC bug. */ 194 #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) 195 #define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) 196 #endif /* CONFIG_HOTPLUG_CPU */ 197 198 #ifdef CONFIG_PM_SLEEP_SMP 199 extern int disable_nonboot_cpus(void); 200 extern void enable_nonboot_cpus(void); 201 #else /* !CONFIG_PM_SLEEP_SMP */ 202 static inline int disable_nonboot_cpus(void) { return 0; } 203 static inline void enable_nonboot_cpus(void) {} 204 #endif /* !CONFIG_PM_SLEEP_SMP */ 205 206 #endif /* _LINUX_CPU_H_ */ 207