LXR linux/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 *
  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#include <linux/cpuhotplug.h>
  20
  21struct device;
  22struct device_node;
  23struct attribute_group;
  24
  25struct cpu {
  26        int node_id;            /* The node which contains the CPU */
  27        int hotpluggable;       /* creates sysfs control file if hotpluggable */
  28        struct device dev;
  29};
  30
  31extern void boot_cpu_init(void);
  32extern void boot_cpu_state_init(void);
  33
  34extern int register_cpu(struct cpu *cpu, int num);
  35extern struct device *get_cpu_device(unsigned cpu);
  36extern bool cpu_is_hotpluggable(unsigned cpu);
  37extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id);
  38extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
  39                                              int cpu, unsigned int *thread);
  40
  41extern int cpu_add_dev_attr(struct device_attribute *attr);
  42extern void cpu_remove_dev_attr(struct device_attribute *attr);
  43
  44extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
  45extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
  46
  47extern __printf(4, 5)
  48struct device *cpu_device_create(struct device *parent, void *drvdata,
  49                                 const struct attribute_group **groups,
  50                                 const char *fmt, ...);
  51#ifdef CONFIG_HOTPLUG_CPU
  52extern void unregister_cpu(struct cpu *cpu);
  53extern ssize_t arch_cpu_probe(const char *, size_t);
  54extern ssize_t arch_cpu_release(const char *, size_t);
  55#endif
  56struct notifier_block;
  57
  58/*
  59 * CPU notifier priorities.
  60 */
  61enum {
  62        /*
  63         * SCHED_ACTIVE marks a cpu which is coming up active during
  64         * CPU_ONLINE and CPU_DOWN_FAILED and must be the first
  65         * notifier.  CPUSET_ACTIVE adjusts cpuset according to
  66         * cpu_active mask right after SCHED_ACTIVE.  During
  67         * CPU_DOWN_PREPARE, SCHED_INACTIVE and CPUSET_INACTIVE are
  68         * ordered in the similar way.
  69         *
  70         * This ordering guarantees consistent cpu_active mask and
  71         * migration behavior to all cpu notifiers.
  72         */
  73        CPU_PRI_SCHED_ACTIVE    = INT_MAX,
  74        CPU_PRI_CPUSET_ACTIVE   = INT_MAX - 1,
  75        CPU_PRI_SCHED_INACTIVE  = INT_MIN + 1,
  76        CPU_PRI_CPUSET_INACTIVE = INT_MIN,
  77
  78        /* migration should happen before other stuff but after perf */
  79        CPU_PRI_PERF            = 20,
  80        CPU_PRI_MIGRATION       = 10,
  81
  82        /* bring up workqueues before normal notifiers and down after */
  83        CPU_PRI_WORKQUEUE_UP    = 5,
  84        CPU_PRI_WORKQUEUE_DOWN  = -5,
  85};
  86
  87#define CPU_ONLINE              0x0002 /* CPU (unsigned)v is up */
  88#define CPU_UP_PREPARE          0x0003 /* CPU (unsigned)v coming up */
  89#define CPU_UP_CANCELED         0x0004 /* CPU (unsigned)v NOT coming up */
  90#define CPU_DOWN_PREPARE        0x0005 /* CPU (unsigned)v going down */
  91#define CPU_DOWN_FAILED         0x0006 /* CPU (unsigned)v NOT going down */
  92#define CPU_DEAD                0x0007 /* CPU (unsigned)v dead */
  93#define CPU_DYING               0x0008 /* CPU (unsigned)v not running any task,
  94                                        * not handling interrupts, soon dead.
  95                                        * Called on the dying cpu, interrupts
  96                                        * are already disabled. Must not
  97                                        * sleep, must not fail */
  98#define CPU_POST_DEAD           0x0009 /* CPU (unsigned)v dead, cpu_hotplug
  99                                        * lock is dropped */
 100#define CPU_STARTING            0x000A /* CPU (unsigned)v soon running.
 101                                        * Called on the new cpu, just before
 102                                        * enabling interrupts. Must not sleep,
 103                                        * must not fail */
 104#define CPU_BROKEN              0x000B /* CPU (unsigned)v did not die properly,
 105                                        * perhaps due to preemption. */
 106
 107/* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
 108 * operation in progress
 109 */
 110#define CPU_TASKS_FROZEN        0x0010
 111
 112#define CPU_ONLINE_FROZEN       (CPU_ONLINE | CPU_TASKS_FROZEN)
 113#define CPU_UP_PREPARE_FROZEN   (CPU_UP_PREPARE | CPU_TASKS_FROZEN)
 114#define CPU_UP_CANCELED_FROZEN  (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
 115#define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
 116#define CPU_DOWN_FAILED_FROZEN  (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
 117#define CPU_DEAD_FROZEN         (CPU_DEAD | CPU_TASKS_FROZEN)
 118#define CPU_DYING_FROZEN        (CPU_DYING | CPU_TASKS_FROZEN)
 119#define CPU_STARTING_FROZEN     (CPU_STARTING | CPU_TASKS_FROZEN)
 120
 121
 122#ifdef CONFIG_SMP
 123extern bool cpuhp_tasks_frozen;
 124/* Need to know about CPUs going up/down? */
 125#if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
 126#define cpu_notifier(fn, pri) {                                 \
 127        static struct notifier_block fn##_nb =                  \
 128                { .notifier_call = fn, .priority = pri };       \
 129        register_cpu_notifier(&fn##_nb);                        \
 130}
 131
 132#define __cpu_notifier(fn, pri) {                               \
 133        static struct notifier_block fn##_nb =                  \
 134                { .notifier_call = fn, .priority = pri };       \
 135        __register_cpu_notifier(&fn##_nb);                      \
 136}
 137#else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
 138#define cpu_notifier(fn, pri)   do { (void)(fn); } while (0)
 139#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0)
 140#endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */
 141
 142#ifdef CONFIG_HOTPLUG_CPU
 143extern int register_cpu_notifier(struct notifier_block *nb);
 144extern int __register_cpu_notifier(struct notifier_block *nb);
 145extern void unregister_cpu_notifier(struct notifier_block *nb);
 146extern void __unregister_cpu_notifier(struct notifier_block *nb);
 147#else
 148
 149#ifndef MODULE
 150extern int register_cpu_notifier(struct notifier_block *nb);
 151extern int __register_cpu_notifier(struct notifier_block *nb);
 152#else
 153static inline int register_cpu_notifier(struct notifier_block *nb)
 154{
 155        return 0;
 156}
 157
 158static inline int __register_cpu_notifier(struct notifier_block *nb)
 159{
 160        return 0;
 161}
 162#endif
 163
 164static inline void unregister_cpu_notifier(struct notifier_block *nb)
 165{
 166}
 167
 168static inline void __unregister_cpu_notifier(struct notifier_block *nb)
 169{
 170}
 171#endif
 172
 173int cpu_up(unsigned int cpu);
 174void notify_cpu_starting(unsigned int cpu);
 175extern void cpu_maps_update_begin(void);
 176extern void cpu_maps_update_done(void);
 177
 178#define cpu_notifier_register_begin     cpu_maps_update_begin
 179#define cpu_notifier_register_done      cpu_maps_update_done
 180
 181#else   /* CONFIG_SMP */
 182#define cpuhp_tasks_frozen      0
 183
 184#define cpu_notifier(fn, pri)   do { (void)(fn); } while (0)
 185#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0)
 186
 187static inline int register_cpu_notifier(struct notifier_block *nb)
 188{
 189        return 0;
 190}
 191
 192static inline int __register_cpu_notifier(struct notifier_block *nb)
 193{
 194        return 0;
 195}
 196
 197static inline void unregister_cpu_notifier(struct notifier_block *nb)
 198{
 199}
 200
 201static inline void __unregister_cpu_notifier(struct notifier_block *nb)
 202{
 203}
 204
 205static inline void cpu_maps_update_begin(void)
 206{
 207}
 208
 209static inline void cpu_maps_update_done(void)
 210{
 211}
 212
 213static inline void cpu_notifier_register_begin(void)
 214{
 215}
 216
 217static inline void cpu_notifier_register_done(void)
 218{
 219}
 220
 221#endif /* CONFIG_SMP */
 222extern struct bus_type cpu_subsys;
 223
 224#ifdef CONFIG_HOTPLUG_CPU
 225/* Stop CPUs going up and down. */
 226
 227extern void cpu_hotplug_begin(void);
 228extern void cpu_hotplug_done(void);
 229extern void get_online_cpus(void);
 230extern void put_online_cpus(void);
 231extern void cpu_hotplug_disable(void);
 232extern void cpu_hotplug_enable(void);
 233#define hotcpu_notifier(fn, pri)        cpu_notifier(fn, pri)
 234#define __hotcpu_notifier(fn, pri)      __cpu_notifier(fn, pri)
 235#define register_hotcpu_notifier(nb)    register_cpu_notifier(nb)
 236#define __register_hotcpu_notifier(nb)  __register_cpu_notifier(nb)
 237#define unregister_hotcpu_notifier(nb)  unregister_cpu_notifier(nb)
 238#define __unregister_hotcpu_notifier(nb)        __unregister_cpu_notifier(nb)
 239void clear_tasks_mm_cpumask(int cpu);
 240int cpu_down(unsigned int cpu);
 241
 242#else           /* CONFIG_HOTPLUG_CPU */
 243
 244static inline void cpu_hotplug_begin(void) {}
 245static inline void cpu_hotplug_done(void) {}
 246#define get_online_cpus()       do { } while (0)
 247#define put_online_cpus()       do { } while (0)
 248#define cpu_hotplug_disable()   do { } while (0)
 249#define cpu_hotplug_enable()    do { } while (0)
 250#define hotcpu_notifier(fn, pri)        do { (void)(fn); } while (0)
 251#define __hotcpu_notifier(fn, pri)      do { (void)(fn); } while (0)
 252/* These aren't inline functions due to a GCC bug. */
 253#define register_hotcpu_notifier(nb)    ({ (void)(nb); 0; })
 254#define __register_hotcpu_notifier(nb)  ({ (void)(nb); 0; })
 255#define unregister_hotcpu_notifier(nb)  ({ (void)(nb); })
 256#define __unregister_hotcpu_notifier(nb)        ({ (void)(nb); })
 257#endif          /* CONFIG_HOTPLUG_CPU */
 258
 259#ifdef CONFIG_PM_SLEEP_SMP
 260extern int disable_nonboot_cpus(void);
 261extern void enable_nonboot_cpus(void);
 262#else /* !CONFIG_PM_SLEEP_SMP */
 263static inline int disable_nonboot_cpus(void) { return 0; }
 264static inline void enable_nonboot_cpus(void) {}
 265#endif /* !CONFIG_PM_SLEEP_SMP */
 266
 267void cpu_startup_entry(enum cpuhp_state state);
 268
 269void cpu_idle_poll_ctrl(bool enable);
 270
 271void arch_cpu_idle(void);
 272void arch_cpu_idle_prepare(void);
 273void arch_cpu_idle_enter(void);
 274void arch_cpu_idle_exit(void);
 275void arch_cpu_idle_dead(void);
 276
 277int cpu_report_state(int cpu);
 278int cpu_check_up_prepare(int cpu);
 279void cpu_set_state_online(int cpu);
 280#ifdef CONFIG_HOTPLUG_CPU
 281bool cpu_wait_death(unsigned int cpu, int seconds);
 282bool cpu_report_death(void);
 283void cpuhp_report_idle_dead(void);
 284#else
 285static inline void cpuhp_report_idle_dead(void) { }
 286#endif /* #ifdef CONFIG_HOTPLUG_CPU */
 287
 288#endif /* _LINUX_CPU_H_ */
 289