include/linux/cpuhotplug.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __CPUHOTPLUG_H
   3 #define __CPUHOTPLUG_H
   4
   5 #include <linux/types.h>
   6
   7 /*
   8  * CPU-up                       CPU-down
   9  *
  10  * BP           AP              BP              AP
  11  *
  12  * OFFLINE                      OFFLINE
  13  *   |                            ^
  14  *   v                            |
  15  * BRINGUP_CPU->AP_OFFLINE      BRINGUP_CPU  <- AP_IDLE_DEAD (idle thread/play_dead)
  16  *                |                             AP_OFFLINE
  17  *                v (IRQ-off)     ,---------------^
  18  *              AP_ONLNE          | (stop_machine)
  19  *                |             TEARDOWN_CPU <- AP_ONLINE_IDLE
  20  *                |                               ^
  21  *                v                               |
  22  *              AP_ACTIVE                       AP_ACTIVE
  23  */
  24
  25 /*
  26  * CPU hotplug states. The state machine invokes the installed state
  27  * startup callbacks sequentially from CPUHP_OFFLINE + 1 to CPUHP_ONLINE
  28  * during a CPU online operation. During a CPU offline operation the
  29  * installed teardown callbacks are invoked in the reverse order from
  30  * CPU_ONLINE - 1 down to CPUHP_OFFLINE.
  31  *
  32  * The state space has three sections: PREPARE, STARTING and ONLINE.
  33  *
  34  * PREPARE: The callbacks are invoked on a control CPU before the
  35  * hotplugged CPU is started up or after the hotplugged CPU has died.
  36  *
  37  * STARTING: The callbacks are invoked on the hotplugged CPU from the low level
  38  * hotplug startup/teardown code with interrupts disabled.
  39  *
  40  * ONLINE: The callbacks are invoked on the hotplugged CPU from the per CPU
  41  * hotplug thread with interrupts and preemption enabled.
  42  *
  43  * Adding explicit states to this enum is only necessary when:
  44  *
  45  * 1) The state is within the STARTING section
  46  *
  47  * 2) The state has ordering constraints vs. other states in the
  48  *    same section.
  49  *
  50  * If neither #1 nor #2 apply, please use the dynamic state space when
  51  * setting up a state by using CPUHP_PREPARE_DYN or CPUHP_PREPARE_ONLINE
  52  * for the @state argument of the setup function.
  53  *
  54  * See Documentation/core-api/cpu_hotplug.rst for further information and
  55  * examples.
  56  */
  57 enum cpuhp_state {
  58         CPUHP_INVALID = -1,
  59
  60         /* PREPARE section invoked on a control CPU */
  61         CPUHP_OFFLINE = 0,
  62         CPUHP_CREATE_THREADS,
  63         CPUHP_PERF_PREPARE,
  64         CPUHP_PERF_X86_PREPARE,
  65         CPUHP_PERF_X86_AMD_UNCORE_PREP,
  66         CPUHP_PERF_POWER,
  67         CPUHP_PERF_SUPERH,
  68         CPUHP_X86_HPET_DEAD,
  69         CPUHP_X86_APB_DEAD,
  70         CPUHP_X86_MCE_DEAD,
  71         CPUHP_VIRT_NET_DEAD,
  72         CPUHP_SLUB_DEAD,
  73         CPUHP_DEBUG_OBJ_DEAD,
  74         CPUHP_MM_WRITEBACK_DEAD,
  75         /* Must be after CPUHP_MM_VMSTAT_DEAD */
  76         CPUHP_MM_DEMOTION_DEAD,
  77         CPUHP_MM_VMSTAT_DEAD,
  78         CPUHP_SOFTIRQ_DEAD,
  79         CPUHP_NET_MVNETA_DEAD,
  80         CPUHP_CPUIDLE_DEAD,
  81         CPUHP_ARM64_FPSIMD_DEAD,
  82         CPUHP_ARM_OMAP_WAKE_DEAD,
  83         CPUHP_IRQ_POLL_DEAD,
  84         CPUHP_BLOCK_SOFTIRQ_DEAD,
  85         CPUHP_BIO_DEAD,
  86         CPUHP_ACPI_CPUDRV_DEAD,
  87         CPUHP_S390_PFAULT_DEAD,
  88         CPUHP_BLK_MQ_DEAD,
  89         CPUHP_FS_BUFF_DEAD,
  90         CPUHP_PRINTK_DEAD,
  91         CPUHP_MM_MEMCQ_DEAD,
  92         CPUHP_XFS_DEAD,
  93         CPUHP_PERCPU_CNT_DEAD,
  94         CPUHP_RADIX_DEAD,
  95         CPUHP_PAGE_ALLOC,
  96         CPUHP_NET_DEV_DEAD,
  97         CPUHP_PCI_XGENE_DEAD,
  98         CPUHP_IOMMU_IOVA_DEAD,
  99         CPUHP_LUSTRE_CFS_DEAD,
 100         CPUHP_AP_ARM_CACHE_B15_RAC_DEAD,
 101         CPUHP_PADATA_DEAD,
 102         CPUHP_AP_DTPM_CPU_DEAD,
 103         CPUHP_RANDOM_PREPARE,
 104         CPUHP_WORKQUEUE_PREP,
 105         CPUHP_POWER_NUMA_PREPARE,
 106         CPUHP_HRTIMERS_PREPARE,
 107         CPUHP_PROFILE_PREPARE,
 108         CPUHP_X2APIC_PREPARE,
 109         CPUHP_SMPCFD_PREPARE,
 110         CPUHP_RELAY_PREPARE,
 111         CPUHP_SLAB_PREPARE,
 112         CPUHP_MD_RAID5_PREPARE,
 113         CPUHP_RCUTREE_PREP,
 114         CPUHP_CPUIDLE_COUPLED_PREPARE,
 115         CPUHP_POWERPC_PMAC_PREPARE,
 116         CPUHP_POWERPC_MMU_CTX_PREPARE,
 117         CPUHP_XEN_PREPARE,
 118         CPUHP_XEN_EVTCHN_PREPARE,
 119         CPUHP_ARM_SHMOBILE_SCU_PREPARE,
 120         CPUHP_SH_SH3X_PREPARE,
 121         CPUHP_NET_FLOW_PREPARE,
 122         CPUHP_TOPOLOGY_PREPARE,
 123         CPUHP_NET_IUCV_PREPARE,
 124         CPUHP_ARM_BL_PREPARE,
 125         CPUHP_TRACE_RB_PREPARE,
 126         CPUHP_MM_ZS_PREPARE,
 127         CPUHP_MM_ZSWP_MEM_PREPARE,
 128         CPUHP_MM_ZSWP_POOL_PREPARE,
 129         CPUHP_KVM_PPC_BOOK3S_PREPARE,
 130         CPUHP_ZCOMP_PREPARE,
 131         CPUHP_TIMERS_PREPARE,
 132         CPUHP_MIPS_SOC_PREPARE,
 133         CPUHP_LOONGARCH_SOC_PREPARE,
 134         CPUHP_BP_PREPARE_DYN,
 135         CPUHP_BP_PREPARE_DYN_END                = CPUHP_BP_PREPARE_DYN + 20,
 136         CPUHP_BRINGUP_CPU,
 137
 138         /*
 139          * STARTING section invoked on the hotplugged CPU in low level
 140          * bringup and teardown code.
 141          */
 142         CPUHP_AP_IDLE_DEAD,
 143         CPUHP_AP_OFFLINE,
 144         CPUHP_AP_SCHED_STARTING,
 145         CPUHP_AP_RCUTREE_DYING,
 146         CPUHP_AP_CPU_PM_STARTING,
 147         CPUHP_AP_IRQ_GIC_STARTING,
 148         CPUHP_AP_IRQ_HIP04_STARTING,
 149         CPUHP_AP_IRQ_APPLE_AIC_STARTING,
 150         CPUHP_AP_IRQ_ARMADA_XP_STARTING,
 151         CPUHP_AP_IRQ_BCM2836_STARTING,
 152         CPUHP_AP_IRQ_MIPS_GIC_STARTING,
 153         CPUHP_AP_IRQ_RISCV_STARTING,
 154         CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING,
 155         CPUHP_AP_ARM_MVEBU_COHERENCY,
 156         CPUHP_AP_MICROCODE_LOADER,
 157         CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING,
 158         CPUHP_AP_PERF_X86_STARTING,
 159         CPUHP_AP_PERF_X86_AMD_IBS_STARTING,
 160         CPUHP_AP_PERF_X86_CQM_STARTING,
 161         CPUHP_AP_PERF_X86_CSTATE_STARTING,
 162         CPUHP_AP_PERF_XTENSA_STARTING,
 163         CPUHP_AP_MIPS_OP_LOONGSON3_STARTING,
 164         CPUHP_AP_ARM_SDEI_STARTING,
 165         CPUHP_AP_ARM_VFP_STARTING,
 166         CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING,
 167         CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING,
 168         CPUHP_AP_PERF_ARM_ACPI_STARTING,
 169         CPUHP_AP_PERF_ARM_STARTING,
 170         CPUHP_AP_PERF_RISCV_STARTING,
 171         CPUHP_AP_ARM_L2X0_STARTING,
 172         CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
 173         CPUHP_AP_ARM_ARCH_TIMER_STARTING,
 174         CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
 175         CPUHP_AP_JCORE_TIMER_STARTING,
 176         CPUHP_AP_ARM_TWD_STARTING,
 177         CPUHP_AP_QCOM_TIMER_STARTING,
 178         CPUHP_AP_TEGRA_TIMER_STARTING,
 179         CPUHP_AP_ARMADA_TIMER_STARTING,
 180         CPUHP_AP_MARCO_TIMER_STARTING,
 181         CPUHP_AP_MIPS_GIC_TIMER_STARTING,
 182         CPUHP_AP_ARC_TIMER_STARTING,
 183         CPUHP_AP_RISCV_TIMER_STARTING,
 184         CPUHP_AP_CLINT_TIMER_STARTING,
 185         CPUHP_AP_CSKY_TIMER_STARTING,
 186         CPUHP_AP_TI_GP_TIMER_STARTING,
 187         CPUHP_AP_HYPERV_TIMER_STARTING,
 188         CPUHP_AP_KVM_STARTING,
 189         CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
 190         CPUHP_AP_KVM_ARM_VGIC_STARTING,
 191         CPUHP_AP_KVM_ARM_TIMER_STARTING,
 192         /* Must be the last timer callback */
 193         CPUHP_AP_DUMMY_TIMER_STARTING,
 194         CPUHP_AP_ARM_XEN_STARTING,
 195         CPUHP_AP_ARM_CORESIGHT_STARTING,
 196         CPUHP_AP_ARM_CORESIGHT_CTI_STARTING,
 197         CPUHP_AP_ARM64_ISNDEP_STARTING,
 198         CPUHP_AP_SMPCFD_DYING,
 199         CPUHP_AP_X86_TBOOT_DYING,
 200         CPUHP_AP_ARM_CACHE_B15_RAC_DYING,
 201         CPUHP_AP_ONLINE,
 202         CPUHP_TEARDOWN_CPU,
 203
 204         /* Online section invoked on the hotplugged CPU from the hotplug thread */
 205         CPUHP_AP_ONLINE_IDLE,
 206         CPUHP_AP_SCHED_WAIT_EMPTY,
 207         CPUHP_AP_SMPBOOT_THREADS,
 208         CPUHP_AP_X86_VDSO_VMA_ONLINE,
 209         CPUHP_AP_IRQ_AFFINITY_ONLINE,
 210         CPUHP_AP_BLK_MQ_ONLINE,
 211         CPUHP_AP_ARM_MVEBU_SYNC_CLOCKS,
 212         CPUHP_AP_X86_INTEL_EPB_ONLINE,
 213         CPUHP_AP_PERF_ONLINE,
 214         CPUHP_AP_PERF_X86_ONLINE,
 215         CPUHP_AP_PERF_X86_UNCORE_ONLINE,
 216         CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE,
 217         CPUHP_AP_PERF_X86_AMD_POWER_ONLINE,
 218         CPUHP_AP_PERF_X86_RAPL_ONLINE,
 219         CPUHP_AP_PERF_X86_CQM_ONLINE,
 220         CPUHP_AP_PERF_X86_CSTATE_ONLINE,
 221         CPUHP_AP_PERF_X86_IDXD_ONLINE,
 222         CPUHP_AP_PERF_S390_CF_ONLINE,
 223         CPUHP_AP_PERF_S390_SF_ONLINE,
 224         CPUHP_AP_PERF_ARM_CCI_ONLINE,
 225         CPUHP_AP_PERF_ARM_CCN_ONLINE,
 226         CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE,
 227         CPUHP_AP_PERF_ARM_HISI_DDRC_ONLINE,
 228         CPUHP_AP_PERF_ARM_HISI_HHA_ONLINE,
 229         CPUHP_AP_PERF_ARM_HISI_L3_ONLINE,
 230         CPUHP_AP_PERF_ARM_HISI_PA_ONLINE,
 231         CPUHP_AP_PERF_ARM_HISI_SLLC_ONLINE,
 232         CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE,
 233         CPUHP_AP_PERF_ARM_L2X0_ONLINE,
 234         CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
 235         CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE,
 236         CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE,
 237         CPUHP_AP_PERF_ARM_CAVIUM_TX2_UNCORE_ONLINE,
 238         CPUHP_AP_PERF_ARM_MARVELL_CN10K_DDR_ONLINE,
 239         CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE,
 240         CPUHP_AP_PERF_POWERPC_CORE_IMC_ONLINE,
 241         CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE,
 242         CPUHP_AP_PERF_POWERPC_TRACE_IMC_ONLINE,
 243         CPUHP_AP_PERF_POWERPC_HV_24x7_ONLINE,
 244         CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE,
 245         CPUHP_AP_PERF_CSKY_ONLINE,
 246         CPUHP_AP_WATCHDOG_ONLINE,
 247         CPUHP_AP_WORKQUEUE_ONLINE,
 248         CPUHP_AP_RANDOM_ONLINE,
 249         CPUHP_AP_RCUTREE_ONLINE,
 250         CPUHP_AP_BASE_CACHEINFO_ONLINE,
 251         CPUHP_AP_ONLINE_DYN,
 252         CPUHP_AP_ONLINE_DYN_END         = CPUHP_AP_ONLINE_DYN + 30,
 253         /* Must be after CPUHP_AP_ONLINE_DYN for node_states[N_CPU] update */
 254         CPUHP_AP_MM_DEMOTION_ONLINE,
 255         CPUHP_AP_X86_HPET_ONLINE,
 256         CPUHP_AP_X86_KVM_CLK_ONLINE,
 257         CPUHP_AP_ACTIVE,
 258         CPUHP_ONLINE,
 259 };
 260
 261 int __cpuhp_setup_state(enum cpuhp_state state, const char *name, bool invoke,
 262                         int (*startup)(unsigned int cpu),
 263                         int (*teardown)(unsigned int cpu), bool multi_instance);
 264
 265 int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, const char *name,
 266                                    bool invoke,
 267                                    int (*startup)(unsigned int cpu),
 268                                    int (*teardown)(unsigned int cpu),
 269                                    bool multi_instance);
 270 /**
 271  * cpuhp_setup_state - Setup hotplug state callbacks with calling the @startup
 272  *                     callback
 273  * @state:      The state for which the calls are installed
 274  * @name:       Name of the callback (will be used in debug output)
 275  * @startup:    startup callback function or NULL if not required
 276  * @teardown:   teardown callback function or NULL if not required
 277  *
 278  * Installs the callback functions and invokes the @startup callback on
 279  * the online cpus which have already reached the @state.
 280  */
 281 static inline int cpuhp_setup_state(enum cpuhp_state state,
 282                                     const char *name,
 283                                     int (*startup)(unsigned int cpu),
 284                                     int (*teardown)(unsigned int cpu))
 285 {
 286         return __cpuhp_setup_state(state, name, true, startup, teardown, false);
 287 }
 288
 289 /**
 290  * cpuhp_setup_state_cpuslocked - Setup hotplug state callbacks with calling
 291  *                                @startup callback from a cpus_read_lock()
 292  *                                held region
 293  * @state:      The state for which the calls are installed
 294  * @name:       Name of the callback (will be used in debug output)
 295  * @startup:    startup callback function or NULL if not required
 296  * @teardown:   teardown callback function or NULL if not required
 297  *
 298  * Same as cpuhp_setup_state() except that it must be invoked from within a
 299  * cpus_read_lock() held region.
 300  */
 301 static inline int cpuhp_setup_state_cpuslocked(enum cpuhp_state state,
 302                                                const char *name,
 303                                                int (*startup)(unsigned int cpu),
 304                                                int (*teardown)(unsigned int cpu))
 305 {
 306         return __cpuhp_setup_state_cpuslocked(state, name, true, startup,
 307                                               teardown, false);
 308 }
 309
 310 /**
 311  * cpuhp_setup_state_nocalls - Setup hotplug state callbacks without calling the
 312  *                             @startup callback
 313  * @state:      The state for which the calls are installed
 314  * @name:       Name of the callback.
 315  * @startup:    startup callback function or NULL if not required
 316  * @teardown:   teardown callback function or NULL if not required
 317  *
 318  * Same as cpuhp_setup_state() except that the @startup callback is not
 319  * invoked during installation. NOP if SMP=n or HOTPLUG_CPU=n.
 320  */
 321 static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state,
 322                                             const char *name,
 323                                             int (*startup)(unsigned int cpu),
 324                                             int (*teardown)(unsigned int cpu))
 325 {
 326         return __cpuhp_setup_state(state, name, false, startup, teardown,
 327                                    false);
 328 }
 329
 330 /**
 331  * cpuhp_setup_state_nocalls_cpuslocked - Setup hotplug state callbacks without
 332  *                                        invoking the @startup callback from
 333  *                                        a cpus_read_lock() held region
 334  *                             callbacks
 335  * @state:      The state for which the calls are installed
 336  * @name:       Name of the callback.
 337  * @startup:    startup callback function or NULL if not required
 338  * @teardown:   teardown callback function or NULL if not required
 339  *
 340  * Same as cpuhp_setup_state_nocalls() except that it must be invoked from
 341  * within a cpus_read_lock() held region.
 342  */
 343 static inline int cpuhp_setup_state_nocalls_cpuslocked(enum cpuhp_state state,
 344                                                      const char *name,
 345                                                      int (*startup)(unsigned int cpu),
 346                                                      int (*teardown)(unsigned int cpu))
 347 {
 348         return __cpuhp_setup_state_cpuslocked(state, name, false, startup,
 349                                             teardown, false);
 350 }
 351
 352 /**
 353  * cpuhp_setup_state_multi - Add callbacks for multi state
 354  * @state:      The state for which the calls are installed
 355  * @name:       Name of the callback.
 356  * @startup:    startup callback function or NULL if not required
 357  * @teardown:   teardown callback function or NULL if not required
 358  *
 359  * Sets the internal multi_instance flag and prepares a state to work as a multi
 360  * instance callback. No callbacks are invoked at this point. The callbacks are
 361  * invoked once an instance for this state are registered via
 362  * cpuhp_state_add_instance() or cpuhp_state_add_instance_nocalls()
 363  */
 364 static inline int cpuhp_setup_state_multi(enum cpuhp_state state,
 365                                           const char *name,
 366                                           int (*startup)(unsigned int cpu,
 367                                                          struct hlist_node *node),
 368                                           int (*teardown)(unsigned int cpu,
 369                                                           struct hlist_node *node))
 370 {
 371         return __cpuhp_setup_state(state, name, false,
 372                                    (void *) startup,
 373                                    (void *) teardown, true);
 374 }
 375
 376 int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node,
 377                                bool invoke);
 378 int __cpuhp_state_add_instance_cpuslocked(enum cpuhp_state state,
 379                                           struct hlist_node *node, bool invoke);
 380
 381 /**
 382  * cpuhp_state_add_instance - Add an instance for a state and invoke startup
 383  *                            callback.
 384  * @state:      The state for which the instance is installed
 385  * @node:       The node for this individual state.
 386  *
 387  * Installs the instance for the @state and invokes the registered startup
 388  * callback on the online cpus which have already reached the @state. The
 389  * @state must have been earlier marked as multi-instance by
 390  * cpuhp_setup_state_multi().
 391  */
 392 static inline int cpuhp_state_add_instance(enum cpuhp_state state,
 393                                            struct hlist_node *node)
 394 {
 395         return __cpuhp_state_add_instance(state, node, true);
 396 }
 397
 398 /**
 399  * cpuhp_state_add_instance_nocalls - Add an instance for a state without
 400  *                                    invoking the startup callback.
 401  * @state:      The state for which the instance is installed
 402  * @node:       The node for this individual state.
 403  *
 404  * Installs the instance for the @state. The @state must have been earlier
 405  * marked as multi-instance by cpuhp_setup_state_multi. NOP if SMP=n or
 406  * HOTPLUG_CPU=n.
 407  */
 408 static inline int cpuhp_state_add_instance_nocalls(enum cpuhp_state state,
 409                                                    struct hlist_node *node)
 410 {
 411         return __cpuhp_state_add_instance(state, node, false);
 412 }
 413
 414 /**
 415  * cpuhp_state_add_instance_nocalls_cpuslocked - Add an instance for a state
 416  *                                               without invoking the startup
 417  *                                               callback from a cpus_read_lock()
 418  *                                               held region.
 419  * @state:      The state for which the instance is installed
 420  * @node:       The node for this individual state.
 421  *
 422  * Same as cpuhp_state_add_instance_nocalls() except that it must be
 423  * invoked from within a cpus_read_lock() held region.
 424  */
 425 static inline int
 426 cpuhp_state_add_instance_nocalls_cpuslocked(enum cpuhp_state state,
 427                                             struct hlist_node *node)
 428 {
 429         return __cpuhp_state_add_instance_cpuslocked(state, node, false);
 430 }
 431
 432 void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
 433 void __cpuhp_remove_state_cpuslocked(enum cpuhp_state state, bool invoke);
 434
 435 /**
 436  * cpuhp_remove_state - Remove hotplug state callbacks and invoke the teardown
 437  * @state:      The state for which the calls are removed
 438  *
 439  * Removes the callback functions and invokes the teardown callback on
 440  * the online cpus which have already reached the @state.
 441  */
 442 static inline void cpuhp_remove_state(enum cpuhp_state state)
 443 {
 444         __cpuhp_remove_state(state, true);
 445 }
 446
 447 /**
 448  * cpuhp_remove_state_nocalls - Remove hotplug state callbacks without invoking
 449  *                              the teardown callback
 450  * @state:      The state for which the calls are removed
 451  */
 452 static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state)
 453 {
 454         __cpuhp_remove_state(state, false);
 455 }
 456
 457 /**
 458  * cpuhp_remove_state_nocalls_cpuslocked - Remove hotplug state callbacks without invoking
 459  *                                         teardown from a cpus_read_lock() held region.
 460  * @state:      The state for which the calls are removed
 461  *
 462  * Same as cpuhp_remove_state nocalls() except that it must be invoked
 463  * from within a cpus_read_lock() held region.
 464  */
 465 static inline void cpuhp_remove_state_nocalls_cpuslocked(enum cpuhp_state state)
 466 {
 467         __cpuhp_remove_state_cpuslocked(state, false);
 468 }
 469
 470 /**
 471  * cpuhp_remove_multi_state - Remove hotplug multi state callback
 472  * @state:      The state for which the calls are removed
 473  *
 474  * Removes the callback functions from a multi state. This is the reverse of
 475  * cpuhp_setup_state_multi(). All instances should have been removed before
 476  * invoking this function.
 477  */
 478 static inline void cpuhp_remove_multi_state(enum cpuhp_state state)
 479 {
 480         __cpuhp_remove_state(state, false);
 481 }
 482
 483 int __cpuhp_state_remove_instance(enum cpuhp_state state,
 484                                   struct hlist_node *node, bool invoke);
 485
 486 /**
 487  * cpuhp_state_remove_instance - Remove hotplug instance from state and invoke
 488  *                               the teardown callback
 489  * @state:      The state from which the instance is removed
 490  * @node:       The node for this individual state.
 491  *
 492  * Removes the instance and invokes the teardown callback on the online cpus
 493  * which have already reached @state.
 494  */
 495 static inline int cpuhp_state_remove_instance(enum cpuhp_state state,
 496                                               struct hlist_node *node)
 497 {
 498         return __cpuhp_state_remove_instance(state, node, true);
 499 }
 500
 501 /**
 502  * cpuhp_state_remove_instance_nocalls - Remove hotplug instance from state
 503  *                                       without invoking the teardown callback
 504  * @state:      The state from which the instance is removed
 505  * @node:       The node for this individual state.
 506  *
 507  * Removes the instance without invoking the teardown callback.
 508  */
 509 static inline int cpuhp_state_remove_instance_nocalls(enum cpuhp_state state,
 510                                                       struct hlist_node *node)
 511 {
 512         return __cpuhp_state_remove_instance(state, node, false);
 513 }
 514
 515 #ifdef CONFIG_SMP
 516 void cpuhp_online_idle(enum cpuhp_state state);
 517 #else
 518 static inline void cpuhp_online_idle(enum cpuhp_state state) { }
 519 #endif
 520
 521 #endif