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_WORKQUEUE_PREP,
 104         CPUHP_POWER_NUMA_PREPARE,
 105         CPUHP_HRTIMERS_PREPARE,
 106         CPUHP_PROFILE_PREPARE,
 107         CPUHP_X2APIC_PREPARE,
 108         CPUHP_SMPCFD_PREPARE,
 109         CPUHP_RELAY_PREPARE,
 110         CPUHP_SLAB_PREPARE,
 111         CPUHP_MD_RAID5_PREPARE,
 112         CPUHP_RCUTREE_PREP,
 113         CPUHP_CPUIDLE_COUPLED_PREPARE,
 114         CPUHP_POWERPC_PMAC_PREPARE,
 115         CPUHP_POWERPC_MMU_CTX_PREPARE,
 116         CPUHP_XEN_PREPARE,
 117         CPUHP_XEN_EVTCHN_PREPARE,
 118         CPUHP_ARM_SHMOBILE_SCU_PREPARE,
 119         CPUHP_SH_SH3X_PREPARE,
 120         CPUHP_NET_FLOW_PREPARE,
 121         CPUHP_TOPOLOGY_PREPARE,
 122         CPUHP_NET_IUCV_PREPARE,
 123         CPUHP_ARM_BL_PREPARE,
 124         CPUHP_TRACE_RB_PREPARE,
 125         CPUHP_MM_ZS_PREPARE,
 126         CPUHP_MM_ZSWP_MEM_PREPARE,
 127         CPUHP_MM_ZSWP_POOL_PREPARE,
 128         CPUHP_KVM_PPC_BOOK3S_PREPARE,
 129         CPUHP_ZCOMP_PREPARE,
 130         CPUHP_TIMERS_PREPARE,
 131         CPUHP_MIPS_SOC_PREPARE,
 132         CPUHP_BP_PREPARE_DYN,
 133         CPUHP_BP_PREPARE_DYN_END                = CPUHP_BP_PREPARE_DYN + 20,
 134         CPUHP_BRINGUP_CPU,
 135
 136         /*
 137          * STARTING section invoked on the hotplugged CPU in low level
 138          * bringup and teardown code.
 139          */
 140         CPUHP_AP_IDLE_DEAD,
 141         CPUHP_AP_OFFLINE,
 142         CPUHP_AP_SCHED_STARTING,
 143         CPUHP_AP_RCUTREE_DYING,
 144         CPUHP_AP_CPU_PM_STARTING,
 145         CPUHP_AP_IRQ_GIC_STARTING,
 146         CPUHP_AP_IRQ_HIP04_STARTING,
 147         CPUHP_AP_IRQ_APPLE_AIC_STARTING,
 148         CPUHP_AP_IRQ_ARMADA_XP_STARTING,
 149         CPUHP_AP_IRQ_BCM2836_STARTING,
 150         CPUHP_AP_IRQ_MIPS_GIC_STARTING,
 151         CPUHP_AP_IRQ_RISCV_STARTING,
 152         CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING,
 153         CPUHP_AP_ARM_MVEBU_COHERENCY,
 154         CPUHP_AP_MICROCODE_LOADER,
 155         CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING,
 156         CPUHP_AP_PERF_X86_STARTING,
 157         CPUHP_AP_PERF_X86_AMD_IBS_STARTING,
 158         CPUHP_AP_PERF_X86_CQM_STARTING,
 159         CPUHP_AP_PERF_X86_CSTATE_STARTING,
 160         CPUHP_AP_PERF_XTENSA_STARTING,
 161         CPUHP_AP_MIPS_OP_LOONGSON3_STARTING,
 162         CPUHP_AP_ARM_SDEI_STARTING,
 163         CPUHP_AP_ARM_VFP_STARTING,
 164         CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING,
 165         CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING,
 166         CPUHP_AP_PERF_ARM_ACPI_STARTING,
 167         CPUHP_AP_PERF_ARM_STARTING,
 168         CPUHP_AP_ARM_L2X0_STARTING,
 169         CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
 170         CPUHP_AP_ARM_ARCH_TIMER_STARTING,
 171         CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
 172         CPUHP_AP_JCORE_TIMER_STARTING,
 173         CPUHP_AP_ARM_TWD_STARTING,
 174         CPUHP_AP_QCOM_TIMER_STARTING,
 175         CPUHP_AP_TEGRA_TIMER_STARTING,
 176         CPUHP_AP_ARMADA_TIMER_STARTING,
 177         CPUHP_AP_MARCO_TIMER_STARTING,
 178         CPUHP_AP_MIPS_GIC_TIMER_STARTING,
 179         CPUHP_AP_ARC_TIMER_STARTING,
 180         CPUHP_AP_RISCV_TIMER_STARTING,
 181         CPUHP_AP_CLINT_TIMER_STARTING,
 182         CPUHP_AP_CSKY_TIMER_STARTING,
 183         CPUHP_AP_TI_GP_TIMER_STARTING,
 184         CPUHP_AP_HYPERV_TIMER_STARTING,
 185         CPUHP_AP_KVM_STARTING,
 186         CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
 187         CPUHP_AP_KVM_ARM_VGIC_STARTING,
 188         CPUHP_AP_KVM_ARM_TIMER_STARTING,
 189         /* Must be the last timer callback */
 190         CPUHP_AP_DUMMY_TIMER_STARTING,
 191         CPUHP_AP_ARM_XEN_STARTING,
 192         CPUHP_AP_ARM_CORESIGHT_STARTING,
 193         CPUHP_AP_ARM_CORESIGHT_CTI_STARTING,
 194         CPUHP_AP_ARM64_ISNDEP_STARTING,
 195         CPUHP_AP_SMPCFD_DYING,
 196         CPUHP_AP_X86_TBOOT_DYING,
 197         CPUHP_AP_ARM_CACHE_B15_RAC_DYING,
 198         CPUHP_AP_ONLINE,
 199         CPUHP_TEARDOWN_CPU,
 200
 201         /* Online section invoked on the hotplugged CPU from the hotplug thread */
 202         CPUHP_AP_ONLINE_IDLE,
 203         CPUHP_AP_SCHED_WAIT_EMPTY,
 204         CPUHP_AP_SMPBOOT_THREADS,
 205         CPUHP_AP_X86_VDSO_VMA_ONLINE,
 206         CPUHP_AP_IRQ_AFFINITY_ONLINE,
 207         CPUHP_AP_BLK_MQ_ONLINE,
 208         CPUHP_AP_ARM_MVEBU_SYNC_CLOCKS,
 209         CPUHP_AP_X86_INTEL_EPB_ONLINE,
 210         CPUHP_AP_PERF_ONLINE,
 211         CPUHP_AP_PERF_X86_ONLINE,
 212         CPUHP_AP_PERF_X86_UNCORE_ONLINE,
 213         CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE,
 214         CPUHP_AP_PERF_X86_AMD_POWER_ONLINE,
 215         CPUHP_AP_PERF_X86_RAPL_ONLINE,
 216         CPUHP_AP_PERF_X86_CQM_ONLINE,
 217         CPUHP_AP_PERF_X86_CSTATE_ONLINE,
 218         CPUHP_AP_PERF_X86_IDXD_ONLINE,
 219         CPUHP_AP_PERF_S390_CF_ONLINE,
 220         CPUHP_AP_PERF_S390_SF_ONLINE,
 221         CPUHP_AP_PERF_ARM_CCI_ONLINE,
 222         CPUHP_AP_PERF_ARM_CCN_ONLINE,
 223         CPUHP_AP_PERF_ARM_HISI_DDRC_ONLINE,
 224         CPUHP_AP_PERF_ARM_HISI_HHA_ONLINE,
 225         CPUHP_AP_PERF_ARM_HISI_L3_ONLINE,
 226         CPUHP_AP_PERF_ARM_HISI_PA_ONLINE,
 227         CPUHP_AP_PERF_ARM_HISI_SLLC_ONLINE,
 228         CPUHP_AP_PERF_ARM_L2X0_ONLINE,
 229         CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
 230         CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE,
 231         CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE,
 232         CPUHP_AP_PERF_ARM_CAVIUM_TX2_UNCORE_ONLINE,
 233         CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE,
 234         CPUHP_AP_PERF_POWERPC_CORE_IMC_ONLINE,
 235         CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE,
 236         CPUHP_AP_PERF_POWERPC_TRACE_IMC_ONLINE,
 237         CPUHP_AP_PERF_POWERPC_HV_24x7_ONLINE,
 238         CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE,
 239         CPUHP_AP_PERF_CSKY_ONLINE,
 240         CPUHP_AP_WATCHDOG_ONLINE,
 241         CPUHP_AP_WORKQUEUE_ONLINE,
 242         CPUHP_AP_RCUTREE_ONLINE,
 243         CPUHP_AP_BASE_CACHEINFO_ONLINE,
 244         CPUHP_AP_ONLINE_DYN,
 245         CPUHP_AP_ONLINE_DYN_END         = CPUHP_AP_ONLINE_DYN + 30,
 246         /* Must be after CPUHP_AP_ONLINE_DYN for node_states[N_CPU] update */
 247         CPUHP_AP_MM_DEMOTION_ONLINE,
 248         CPUHP_AP_X86_HPET_ONLINE,
 249         CPUHP_AP_X86_KVM_CLK_ONLINE,
 250         CPUHP_AP_ACTIVE,
 251         CPUHP_ONLINE,
 252 };
 253
 254 int __cpuhp_setup_state(enum cpuhp_state state, const char *name, bool invoke,
 255                         int (*startup)(unsigned int cpu),
 256                         int (*teardown)(unsigned int cpu), bool multi_instance);
 257
 258 int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, const char *name,
 259                                    bool invoke,
 260                                    int (*startup)(unsigned int cpu),
 261                                    int (*teardown)(unsigned int cpu),
 262                                    bool multi_instance);
 263 /**
 264  * cpuhp_setup_state - Setup hotplug state callbacks with calling the @startup
 265  *                     callback
 266  * @state:      The state for which the calls are installed
 267  * @name:       Name of the callback (will be used in debug output)
 268  * @startup:    startup callback function or NULL if not required
 269  * @teardown:   teardown callback function or NULL if not required
 270  *
 271  * Installs the callback functions and invokes the @startup callback on
 272  * the online cpus which have already reached the @state.
 273  */
 274 static inline int cpuhp_setup_state(enum cpuhp_state state,
 275                                     const char *name,
 276                                     int (*startup)(unsigned int cpu),
 277                                     int (*teardown)(unsigned int cpu))
 278 {
 279         return __cpuhp_setup_state(state, name, true, startup, teardown, false);
 280 }
 281
 282 /**
 283  * cpuhp_setup_state_cpuslocked - Setup hotplug state callbacks with calling
 284  *                                @startup callback from a cpus_read_lock()
 285  *                                held region
 286  * @state:      The state for which the calls are installed
 287  * @name:       Name of the callback (will be used in debug output)
 288  * @startup:    startup callback function or NULL if not required
 289  * @teardown:   teardown callback function or NULL if not required
 290  *
 291  * Same as cpuhp_setup_state() except that it must be invoked from within a
 292  * cpus_read_lock() held region.
 293  */
 294 static inline int cpuhp_setup_state_cpuslocked(enum cpuhp_state state,
 295                                                const char *name,
 296                                                int (*startup)(unsigned int cpu),
 297                                                int (*teardown)(unsigned int cpu))
 298 {
 299         return __cpuhp_setup_state_cpuslocked(state, name, true, startup,
 300                                               teardown, false);
 301 }
 302
 303 /**
 304  * cpuhp_setup_state_nocalls - Setup hotplug state callbacks without calling the
 305  *                             @startup callback
 306  * @state:      The state for which the calls are installed
 307  * @name:       Name of the callback.
 308  * @startup:    startup callback function or NULL if not required
 309  * @teardown:   teardown callback function or NULL if not required
 310  *
 311  * Same as cpuhp_setup_state() except that the @startup callback is not
 312  * invoked during installation. NOP if SMP=n or HOTPLUG_CPU=n.
 313  */
 314 static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state,
 315                                             const char *name,
 316                                             int (*startup)(unsigned int cpu),
 317                                             int (*teardown)(unsigned int cpu))
 318 {
 319         return __cpuhp_setup_state(state, name, false, startup, teardown,
 320                                    false);
 321 }
 322
 323 /**
 324  * cpuhp_setup_state_nocalls_cpuslocked - Setup hotplug state callbacks without
 325  *                                        invoking the @startup callback from
 326  *                                        a cpus_read_lock() held region
 327  *                             callbacks
 328  * @state:      The state for which the calls are installed
 329  * @name:       Name of the callback.
 330  * @startup:    startup callback function or NULL if not required
 331  * @teardown:   teardown callback function or NULL if not required
 332  *
 333  * Same as cpuhp_setup_state_nocalls() except that it must be invoked from
 334  * within a cpus_read_lock() held region.
 335  */
 336 static inline int cpuhp_setup_state_nocalls_cpuslocked(enum cpuhp_state state,
 337                                                      const char *name,
 338                                                      int (*startup)(unsigned int cpu),
 339                                                      int (*teardown)(unsigned int cpu))
 340 {
 341         return __cpuhp_setup_state_cpuslocked(state, name, false, startup,
 342                                             teardown, false);
 343 }
 344
 345 /**
 346  * cpuhp_setup_state_multi - Add callbacks for multi state
 347  * @state:      The state for which the calls are installed
 348  * @name:       Name of the callback.
 349  * @startup:    startup callback function or NULL if not required
 350  * @teardown:   teardown callback function or NULL if not required
 351  *
 352  * Sets the internal multi_instance flag and prepares a state to work as a multi
 353  * instance callback. No callbacks are invoked at this point. The callbacks are
 354  * invoked once an instance for this state are registered via
 355  * cpuhp_state_add_instance() or cpuhp_state_add_instance_nocalls()
 356  */
 357 static inline int cpuhp_setup_state_multi(enum cpuhp_state state,
 358                                           const char *name,
 359                                           int (*startup)(unsigned int cpu,
 360                                                          struct hlist_node *node),
 361                                           int (*teardown)(unsigned int cpu,
 362                                                           struct hlist_node *node))
 363 {
 364         return __cpuhp_setup_state(state, name, false,
 365                                    (void *) startup,
 366                                    (void *) teardown, true);
 367 }
 368
 369 int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node,
 370                                bool invoke);
 371 int __cpuhp_state_add_instance_cpuslocked(enum cpuhp_state state,
 372                                           struct hlist_node *node, bool invoke);
 373
 374 /**
 375  * cpuhp_state_add_instance - Add an instance for a state and invoke startup
 376  *                            callback.
 377  * @state:      The state for which the instance is installed
 378  * @node:       The node for this individual state.
 379  *
 380  * Installs the instance for the @state and invokes the registered startup
 381  * callback on the online cpus which have already reached the @state. The
 382  * @state must have been earlier marked as multi-instance by
 383  * cpuhp_setup_state_multi().
 384  */
 385 static inline int cpuhp_state_add_instance(enum cpuhp_state state,
 386                                            struct hlist_node *node)
 387 {
 388         return __cpuhp_state_add_instance(state, node, true);
 389 }
 390
 391 /**
 392  * cpuhp_state_add_instance_nocalls - Add an instance for a state without
 393  *                                    invoking the startup callback.
 394  * @state:      The state for which the instance is installed
 395  * @node:       The node for this individual state.
 396  *
 397  * Installs the instance for the @state. The @state must have been earlier
 398  * marked as multi-instance by cpuhp_setup_state_multi. NOP if SMP=n or
 399  * HOTPLUG_CPU=n.
 400  */
 401 static inline int cpuhp_state_add_instance_nocalls(enum cpuhp_state state,
 402                                                    struct hlist_node *node)
 403 {
 404         return __cpuhp_state_add_instance(state, node, false);
 405 }
 406
 407 /**
 408  * cpuhp_state_add_instance_nocalls_cpuslocked - Add an instance for a state
 409  *                                               without invoking the startup
 410  *                                               callback from a cpus_read_lock()
 411  *                                               held region.
 412  * @state:      The state for which the instance is installed
 413  * @node:       The node for this individual state.
 414  *
 415  * Same as cpuhp_state_add_instance_nocalls() except that it must be
 416  * invoked from within a cpus_read_lock() held region.
 417  */
 418 static inline int
 419 cpuhp_state_add_instance_nocalls_cpuslocked(enum cpuhp_state state,
 420                                             struct hlist_node *node)
 421 {
 422         return __cpuhp_state_add_instance_cpuslocked(state, node, false);
 423 }
 424
 425 void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
 426 void __cpuhp_remove_state_cpuslocked(enum cpuhp_state state, bool invoke);
 427
 428 /**
 429  * cpuhp_remove_state - Remove hotplug state callbacks and invoke the teardown
 430  * @state:      The state for which the calls are removed
 431  *
 432  * Removes the callback functions and invokes the teardown callback on
 433  * the online cpus which have already reached the @state.
 434  */
 435 static inline void cpuhp_remove_state(enum cpuhp_state state)
 436 {
 437         __cpuhp_remove_state(state, true);
 438 }
 439
 440 /**
 441  * cpuhp_remove_state_nocalls - Remove hotplug state callbacks without invoking
 442  *                              the teardown callback
 443  * @state:      The state for which the calls are removed
 444  */
 445 static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state)
 446 {
 447         __cpuhp_remove_state(state, false);
 448 }
 449
 450 /**
 451  * cpuhp_remove_state_nocalls_cpuslocked - Remove hotplug state callbacks without invoking
 452  *                                         teardown from a cpus_read_lock() held region.
 453  * @state:      The state for which the calls are removed
 454  *
 455  * Same as cpuhp_remove_state nocalls() except that it must be invoked
 456  * from within a cpus_read_lock() held region.
 457  */
 458 static inline void cpuhp_remove_state_nocalls_cpuslocked(enum cpuhp_state state)
 459 {
 460         __cpuhp_remove_state_cpuslocked(state, false);
 461 }
 462
 463 /**
 464  * cpuhp_remove_multi_state - Remove hotplug multi state callback
 465  * @state:      The state for which the calls are removed
 466  *
 467  * Removes the callback functions from a multi state. This is the reverse of
 468  * cpuhp_setup_state_multi(). All instances should have been removed before
 469  * invoking this function.
 470  */
 471 static inline void cpuhp_remove_multi_state(enum cpuhp_state state)
 472 {
 473         __cpuhp_remove_state(state, false);
 474 }
 475
 476 int __cpuhp_state_remove_instance(enum cpuhp_state state,
 477                                   struct hlist_node *node, bool invoke);
 478
 479 /**
 480  * cpuhp_state_remove_instance - Remove hotplug instance from state and invoke
 481  *                               the teardown callback
 482  * @state:      The state from which the instance is removed
 483  * @node:       The node for this individual state.
 484  *
 485  * Removes the instance and invokes the teardown callback on the online cpus
 486  * which have already reached @state.
 487  */
 488 static inline int cpuhp_state_remove_instance(enum cpuhp_state state,
 489                                               struct hlist_node *node)
 490 {
 491         return __cpuhp_state_remove_instance(state, node, true);
 492 }
 493
 494 /**
 495  * cpuhp_state_remove_instance_nocalls - Remove hotplug instance from state
 496  *                                       without invoking the teardown callback
 497  * @state:      The state from which the instance is removed
 498  * @node:       The node for this individual state.
 499  *
 500  * Removes the instance without invoking the teardown callback.
 501  */
 502 static inline int cpuhp_state_remove_instance_nocalls(enum cpuhp_state state,
 503                                                       struct hlist_node *node)
 504 {
 505         return __cpuhp_state_remove_instance(state, node, false);
 506 }
 507
 508 #ifdef CONFIG_SMP
 509 void cpuhp_online_idle(enum cpuhp_state state);
 510 #else
 511 static inline void cpuhp_online_idle(enum cpuhp_state state) { }
 512 #endif
 513
 514 #endif