cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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cpuhotplug.h (17096B)


      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 */
     57enum 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
    261int __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
    265int __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 */
    281static 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 */
    301static 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 */
    321static 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 */
    343static 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 */
    364static 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
    376int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node,
    377			       bool invoke);
    378int __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 */
    392static 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 */
    408static 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 */
    425static inline int
    426cpuhp_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
    432void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
    433void __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 */
    442static 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 */
    452static 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 */
    465static 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 */
    478static inline void cpuhp_remove_multi_state(enum cpuhp_state state)
    479{
    480	__cpuhp_remove_state(state, false);
    481}
    482
    483int __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 */
    495static 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 */
    509static 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
    516void cpuhp_online_idle(enum cpuhp_state state);
    517#else
    518static inline void cpuhp_online_idle(enum cpuhp_state state) { }
    519#endif
    520
    521#endif