include/linux/cpu.h

   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 /*******************************************************************************
  22 * 20131225 marc.huang                                                          *
  23 * CPU Hotplug and idle integration                                             *
  24 *******************************************************************************/
  25 extern atomic_t is_in_hotplug;
  26 /******************************************************************************/
  27
  28 struct device;
  29
  30 struct cpu {
  31         int node_id;            /* The node which contains the CPU */
  32         int hotpluggable;       /* creates sysfs control file if hotpluggable */
  33         struct device dev;
  34 };
  35
  36 extern int register_cpu(struct cpu *cpu, int num);
  37 extern struct device *get_cpu_device(unsigned cpu);
  38 extern bool cpu_is_hotpluggable(unsigned cpu);
  39
  40 extern int cpu_add_dev_attr(struct device_attribute *attr);
  41 extern void cpu_remove_dev_attr(struct device_attribute *attr);
  42
  43 extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
  44 extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
  45
  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 #ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
  54 extern int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env);
  55 extern ssize_t arch_print_cpu_modalias(struct device *dev,
  56                                        struct device_attribute *attr,
  57                                        char *bufptr);
  58 #endif
  59
  60 /*
  61  * CPU notifier priorities.
  62  */
  63 enum {
  64         /*
  65          * SCHED_ACTIVE marks a cpu which is coming up active during
  66          * CPU_ONLINE and CPU_DOWN_FAILED and must be the first
  67          * notifier.  CPUSET_ACTIVE adjusts cpuset according to
  68          * cpu_active mask right after SCHED_ACTIVE.  During
  69          * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are
  70          * ordered in the similar way.
  71          *
  72          * This ordering guarantees consistent cpu_active mask and
  73          * migration behavior to all cpu notifiers.
  74          */
  75         CPU_PRI_SCHED_ACTIVE    = INT_MAX,
  76         CPU_PRI_CPUSET_ACTIVE   = INT_MAX - 1,
  77         CPU_PRI_SCHED_INACTIVE  = INT_MIN + 1,
  78         CPU_PRI_CPUSET_INACTIVE = INT_MIN,
  79
  80         /* migration should happen before other stuff but after perf */
  81         CPU_PRI_PERF            = 20,
  82         CPU_PRI_MIGRATION       = 10,
  83         /* bring up workqueues before normal notifiers and down after */
  84         CPU_PRI_WORKQUEUE_UP    = 5,
  85         CPU_PRI_WORKQUEUE_DOWN  = -5,
  86 };
  87
  88 #define CPU_ONLINE              0x0002 /* CPU (unsigned)v is up */
  89 #define CPU_UP_PREPARE          0x0003 /* CPU (unsigned)v coming up */
  90 #define CPU_UP_CANCELED         0x0004 /* CPU (unsigned)v NOT coming up */
  91 #define CPU_DOWN_PREPARE        0x0005 /* CPU (unsigned)v going down */
  92 #define CPU_DOWN_FAILED         0x0006 /* CPU (unsigned)v NOT going down */
  93 #define CPU_DEAD                0x0007 /* CPU (unsigned)v dead */
  94 #define CPU_DYING               0x0008 /* CPU (unsigned)v not running any task,
  95                                         * not handling interrupts, soon dead.
  96                                         * Called on the dying cpu, interrupts
  97                                         * are already disabled. Must not
  98                                         * sleep, must not fail */
  99 #define CPU_POST_DEAD           0x0009 /* CPU (unsigned)v dead, cpu_hotplug
 100                                         * lock is dropped */
 101 #define CPU_STARTING            0x000A /* CPU (unsigned)v soon running.
 102                                         * Called on the new cpu, just before
 103                                         * enabling interrupts. Must not sleep,
 104                                         * must not fail */
 105
 106 /* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
 107  * operation in progress
 108  */
 109 #define CPU_TASKS_FROZEN        0x0010
 110
 111 #define CPU_ONLINE_FROZEN       (CPU_ONLINE | CPU_TASKS_FROZEN)
 112 #define CPU_UP_PREPARE_FROZEN   (CPU_UP_PREPARE | CPU_TASKS_FROZEN)
 113 #define CPU_UP_CANCELED_FROZEN  (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
 114 #define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
 115 #define CPU_DOWN_FAILED_FROZEN  (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
 116 #define CPU_DEAD_FROZEN         (CPU_DEAD | CPU_TASKS_FROZEN)
 117 #define CPU_DYING_FROZEN        (CPU_DYING | CPU_TASKS_FROZEN)
 118 #define CPU_STARTING_FROZEN     (CPU_STARTING | CPU_TASKS_FROZEN)
 119
 120
 121 #ifdef CONFIG_SMP
 122 /* Need to know about CPUs going up/down? */
 123 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
 124 #define cpu_notifier(fn, pri) {                                 \
 125         static struct notifier_block fn##_nb __cpuinitdata =    \
 126                 { .notifier_call = fn, .priority = pri };       \
 127         register_cpu_notifier(&fn##_nb);                        \
 128 }
 129 #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
 130 #define cpu_notifier(fn, pri)   do { (void)(fn); } while (0)
 131 #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
 132 #ifdef CONFIG_HOTPLUG_CPU
 133 extern int register_cpu_notifier(struct notifier_block *nb);
 134 extern void unregister_cpu_notifier(struct notifier_block *nb);
 135 #else
 136
 137 #ifndef MODULE
 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 #endif
 145
 146 static inline void unregister_cpu_notifier(struct notifier_block *nb)
 147 {
 148 }
 149 #endif
 150
 151 int cpu_up(unsigned int cpu);
 152 void notify_cpu_starting(unsigned int cpu);
 153 extern void cpu_maps_update_begin(void);
 154 extern void cpu_maps_update_done(void);
 155
 156 #else   /* CONFIG_SMP */
 157
 158 #define cpu_notifier(fn, pri)   do { (void)(fn); } while (0)
 159
 160 static inline int register_cpu_notifier(struct notifier_block *nb)
 161 {
 162         return 0;
 163 }
 164
 165 static inline void unregister_cpu_notifier(struct notifier_block *nb)
 166 {
 167 }
 168
 169 static inline void cpu_maps_update_begin(void)
 170 {
 171 }
 172
 173 static inline void cpu_maps_update_done(void)
 174 {
 175 }
 176
 177 #endif /* CONFIG_SMP */
 178 extern struct bus_type cpu_subsys;
 179
 180 #ifdef CONFIG_HOTPLUG_CPU
 181 /* Stop CPUs going up and down. */
 182
 183 extern void get_online_cpus(void);
 184 extern void put_online_cpus(void);
 185 extern void cpu_hotplug_disable(void);
 186 extern void cpu_hotplug_enable(void);
 187 #define hotcpu_notifier(fn, pri)        cpu_notifier(fn, pri)
 188 #define register_hotcpu_notifier(nb)    register_cpu_notifier(nb)
 189 #define unregister_hotcpu_notifier(nb)  unregister_cpu_notifier(nb)
 190 void clear_tasks_mm_cpumask(int cpu);
 191 int cpu_down(unsigned int cpu);
 192
 193 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
 194 extern void cpu_hotplug_driver_lock(void);
 195 extern void cpu_hotplug_driver_unlock(void);
 196 #else
 197 static inline void cpu_hotplug_driver_lock(void)
 198 {
 199 }
 200
 201 static inline void cpu_hotplug_driver_unlock(void)
 202 {
 203 }
 204 #endif
 205
 206 #else           /* CONFIG_HOTPLUG_CPU */
 207
 208 #define get_online_cpus()       do { } while (0)
 209 #define put_online_cpus()       do { } while (0)
 210 #define cpu_hotplug_disable()   do { } while (0)
 211 #define cpu_hotplug_enable()    do { } while (0)
 212 #define hotcpu_notifier(fn, pri)        do { (void)(fn); } while (0)
 213 /* These aren't inline functions due to a GCC bug. */
 214 #define register_hotcpu_notifier(nb)    ({ (void)(nb); 0; })
 215 #define unregister_hotcpu_notifier(nb)  ({ (void)(nb); })
 216 #endif          /* CONFIG_HOTPLUG_CPU */
 217
 218 #ifdef CONFIG_PM_SLEEP_SMP
 219 extern int disable_nonboot_cpus(void);
 220 extern void enable_nonboot_cpus(void);
 221 #else /* !CONFIG_PM_SLEEP_SMP */
 222 static inline int disable_nonboot_cpus(void) { return 0; }
 223 static inline void enable_nonboot_cpus(void) {}
 224 #endif /* !CONFIG_PM_SLEEP_SMP */
 225
 226 enum cpuhp_state {
 227         CPUHP_OFFLINE,
 228         CPUHP_ONLINE,
 229 };
 230
 231 void cpu_startup_entry(enum cpuhp_state state);
 232 void cpu_idle(void);
 233
 234 void cpu_idle_poll_ctrl(bool enable);
 235
 236 void arch_cpu_idle(void);
 237 void arch_cpu_idle_prepare(void);
 238 void arch_cpu_idle_enter(void);
 239 void arch_cpu_idle_exit(void);
 240 void arch_cpu_idle_dead(void);
 241
 242 #define IDLE_START 1
 243 #define IDLE_END 2
 244
 245 void idle_notifier_register(struct notifier_block *n);
 246 void idle_notifier_unregister(struct notifier_block *n);
 247 void idle_notifier_call_chain(unsigned long val);
 248
 249 #endif /* _LINUX_CPU_H_ */