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
  20struct device;
  21struct device_node;
  22struct attribute_group;
  23
  24struct 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
  30extern int register_cpu(struct cpu *cpu, int num);
  31extern struct device *get_cpu_device(unsigned cpu);
  32extern bool cpu_is_hotpluggable(unsigned cpu);
  33extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id);
  34extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
  35                                              int cpu, unsigned int *thread);
  36
  37extern int cpu_add_dev_attr(struct device_attribute *attr);
  38extern void cpu_remove_dev_attr(struct device_attribute *attr);
  39
  40extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
  41extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
  42
  43extern 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
  47extern void unregister_cpu(struct cpu *cpu);
  48extern ssize_t arch_cpu_probe(const char *, size_t);
  49extern ssize_t arch_cpu_release(const char *, size_t);
  50#endif
  51struct notifier_block;
  52
  53/*
  54 * CPU notifier priorities.
  55 */
  56enum {
  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
 134extern int register_cpu_notifier(struct notifier_block *nb);
 135extern int __register_cpu_notifier(struct notifier_block *nb);
 136extern void unregister_cpu_notifier(struct notifier_block *nb);
 137extern void __unregister_cpu_notifier(struct notifier_block *nb);
 138#else
 139
 140#ifndef MODULE
 141extern int register_cpu_notifier(struct notifier_block *nb);
 142extern int __register_cpu_notifier(struct notifier_block *nb);
 143#else
 144static inline int register_cpu_notifier(struct notifier_block *nb)
 145{
 146        return 0;
 147}
 148
 149static inline int __register_cpu_notifier(struct notifier_block *nb)
 150{
 151        return 0;
 152}
 153#endif
 154
 155static inline void unregister_cpu_notifier(struct notifier_block *nb)
 156{
 157}
 158
 159static inline void __unregister_cpu_notifier(struct notifier_block *nb)
 160{
 161}
 162#endif
 163
 164int cpu_up(unsigned int cpu);
 165void notify_cpu_starting(unsigned int cpu);
 166extern void cpu_maps_update_begin(void);
 167extern 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
 177static inline int register_cpu_notifier(struct notifier_block *nb)
 178{
 179        return 0;
 180}
 181
 182static inline int __register_cpu_notifier(struct notifier_block *nb)
 183{
 184        return 0;
 185}
 186
 187static inline void unregister_cpu_notifier(struct notifier_block *nb)
 188{
 189}
 190
 191static inline void __unregister_cpu_notifier(struct notifier_block *nb)
 192{
 193}
 194
 195static inline void cpu_maps_update_begin(void)
 196{
 197}
 198
 199static inline void cpu_maps_update_done(void)
 200{
 201}
 202
 203static inline void cpu_notifier_register_begin(void)
 204{
 205}
 206
 207static inline void cpu_notifier_register_done(void)
 208{
 209}
 210
 211#endif /* CONFIG_SMP */
 212extern struct bus_type cpu_subsys;
 213
 214#ifdef CONFIG_HOTPLUG_CPU
 215/* Stop CPUs going up and down. */
 216
 217extern void cpu_hotplug_begin(void);
 218extern void cpu_hotplug_done(void);
 219extern void get_online_cpus(void);
 220extern bool try_get_online_cpus(void);
 221extern void put_online_cpus(void);
 222extern void cpu_hotplug_disable(void);
 223extern 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)
 230void clear_tasks_mm_cpumask(int cpu);
 231int cpu_down(unsigned int cpu);
 232
 233#else           /* CONFIG_HOTPLUG_CPU */
 234
 235static inline void cpu_hotplug_begin(void) {}
 236static 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
 252extern int disable_nonboot_cpus(void);
 253extern void enable_nonboot_cpus(void);
 254#else /* !CONFIG_PM_SLEEP_SMP */
 255static inline int disable_nonboot_cpus(void) { return 0; }
 256static inline void enable_nonboot_cpus(void) {}
 257#endif /* !CONFIG_PM_SLEEP_SMP */
 258
 259enum cpuhp_state {
 260        CPUHP_OFFLINE,
 261        CPUHP_ONLINE,
 262};
 263
 264void cpu_startup_entry(enum cpuhp_state state);
 265
 266void cpu_idle_poll_ctrl(bool enable);
 267
 268void arch_cpu_idle(void);
 269void arch_cpu_idle_prepare(void);
 270void arch_cpu_idle_enter(void);
 271void arch_cpu_idle_exit(void);
 272void arch_cpu_idle_dead(void);
 273
 274#endif /* _LINUX_CPU_H_ */
 275