xref: /linux-6.15/include/linux/cpuhotplug.h (revision cd3bc044)
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_HISI_PCIE_PMU_ONLINE,
229 	CPUHP_AP_PERF_ARM_L2X0_ONLINE,
230 	CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
231 	CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE,
232 	CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE,
233 	CPUHP_AP_PERF_ARM_CAVIUM_TX2_UNCORE_ONLINE,
234 	CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE,
235 	CPUHP_AP_PERF_POWERPC_CORE_IMC_ONLINE,
236 	CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE,
237 	CPUHP_AP_PERF_POWERPC_TRACE_IMC_ONLINE,
238 	CPUHP_AP_PERF_POWERPC_HV_24x7_ONLINE,
239 	CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE,
240 	CPUHP_AP_PERF_CSKY_ONLINE,
241 	CPUHP_AP_WATCHDOG_ONLINE,
242 	CPUHP_AP_WORKQUEUE_ONLINE,
243 	CPUHP_AP_RCUTREE_ONLINE,
244 	CPUHP_AP_BASE_CACHEINFO_ONLINE,
245 	CPUHP_AP_ONLINE_DYN,
246 	CPUHP_AP_ONLINE_DYN_END		= CPUHP_AP_ONLINE_DYN + 30,
247 	/* Must be after CPUHP_AP_ONLINE_DYN for node_states[N_CPU] update */
248 	CPUHP_AP_MM_DEMOTION_ONLINE,
249 	CPUHP_AP_X86_HPET_ONLINE,
250 	CPUHP_AP_X86_KVM_CLK_ONLINE,
251 	CPUHP_AP_ACTIVE,
252 	CPUHP_ONLINE,
253 };
254 
255 int __cpuhp_setup_state(enum cpuhp_state state,	const char *name, bool invoke,
256 			int (*startup)(unsigned int cpu),
257 			int (*teardown)(unsigned int cpu), bool multi_instance);
258 
259 int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, const char *name,
260 				   bool invoke,
261 				   int (*startup)(unsigned int cpu),
262 				   int (*teardown)(unsigned int cpu),
263 				   bool multi_instance);
264 /**
265  * cpuhp_setup_state - Setup hotplug state callbacks with calling the @startup
266  *                     callback
267  * @state:	The state for which the calls are installed
268  * @name:	Name of the callback (will be used in debug output)
269  * @startup:	startup callback function or NULL if not required
270  * @teardown:	teardown callback function or NULL if not required
271  *
272  * Installs the callback functions and invokes the @startup callback on
273  * the online cpus which have already reached the @state.
274  */
275 static inline int cpuhp_setup_state(enum cpuhp_state state,
276 				    const char *name,
277 				    int (*startup)(unsigned int cpu),
278 				    int (*teardown)(unsigned int cpu))
279 {
280 	return __cpuhp_setup_state(state, name, true, startup, teardown, false);
281 }
282 
283 /**
284  * cpuhp_setup_state_cpuslocked - Setup hotplug state callbacks with calling
285  *				  @startup callback from a cpus_read_lock()
286  *				  held region
287  * @state:	The state for which the calls are installed
288  * @name:	Name of the callback (will be used in debug output)
289  * @startup:	startup callback function or NULL if not required
290  * @teardown:	teardown callback function or NULL if not required
291  *
292  * Same as cpuhp_setup_state() except that it must be invoked from within a
293  * cpus_read_lock() held region.
294  */
295 static inline int cpuhp_setup_state_cpuslocked(enum cpuhp_state state,
296 					       const char *name,
297 					       int (*startup)(unsigned int cpu),
298 					       int (*teardown)(unsigned int cpu))
299 {
300 	return __cpuhp_setup_state_cpuslocked(state, name, true, startup,
301 					      teardown, false);
302 }
303 
304 /**
305  * cpuhp_setup_state_nocalls - Setup hotplug state callbacks without calling the
306  *			       @startup callback
307  * @state:	The state for which the calls are installed
308  * @name:	Name of the callback.
309  * @startup:	startup callback function or NULL if not required
310  * @teardown:	teardown callback function or NULL if not required
311  *
312  * Same as cpuhp_setup_state() except that the @startup callback is not
313  * invoked during installation. NOP if SMP=n or HOTPLUG_CPU=n.
314  */
315 static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state,
316 					    const char *name,
317 					    int (*startup)(unsigned int cpu),
318 					    int (*teardown)(unsigned int cpu))
319 {
320 	return __cpuhp_setup_state(state, name, false, startup, teardown,
321 				   false);
322 }
323 
324 /**
325  * cpuhp_setup_state_nocalls_cpuslocked - Setup hotplug state callbacks without
326  *					  invoking the @startup callback from
327  *					  a cpus_read_lock() held region
328  *			       callbacks
329  * @state:	The state for which the calls are installed
330  * @name:	Name of the callback.
331  * @startup:	startup callback function or NULL if not required
332  * @teardown:	teardown callback function or NULL if not required
333  *
334  * Same as cpuhp_setup_state_nocalls() except that it must be invoked from
335  * within a cpus_read_lock() held region.
336  */
337 static inline int cpuhp_setup_state_nocalls_cpuslocked(enum cpuhp_state state,
338 						     const char *name,
339 						     int (*startup)(unsigned int cpu),
340 						     int (*teardown)(unsigned int cpu))
341 {
342 	return __cpuhp_setup_state_cpuslocked(state, name, false, startup,
343 					    teardown, false);
344 }
345 
346 /**
347  * cpuhp_setup_state_multi - Add callbacks for multi state
348  * @state:	The state for which the calls are installed
349  * @name:	Name of the callback.
350  * @startup:	startup callback function or NULL if not required
351  * @teardown:	teardown callback function or NULL if not required
352  *
353  * Sets the internal multi_instance flag and prepares a state to work as a multi
354  * instance callback. No callbacks are invoked at this point. The callbacks are
355  * invoked once an instance for this state are registered via
356  * cpuhp_state_add_instance() or cpuhp_state_add_instance_nocalls()
357  */
358 static inline int cpuhp_setup_state_multi(enum cpuhp_state state,
359 					  const char *name,
360 					  int (*startup)(unsigned int cpu,
361 							 struct hlist_node *node),
362 					  int (*teardown)(unsigned int cpu,
363 							  struct hlist_node *node))
364 {
365 	return __cpuhp_setup_state(state, name, false,
366 				   (void *) startup,
367 				   (void *) teardown, true);
368 }
369 
370 int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node,
371 			       bool invoke);
372 int __cpuhp_state_add_instance_cpuslocked(enum cpuhp_state state,
373 					  struct hlist_node *node, bool invoke);
374 
375 /**
376  * cpuhp_state_add_instance - Add an instance for a state and invoke startup
377  *                            callback.
378  * @state:	The state for which the instance is installed
379  * @node:	The node for this individual state.
380  *
381  * Installs the instance for the @state and invokes the registered startup
382  * callback on the online cpus which have already reached the @state. The
383  * @state must have been earlier marked as multi-instance by
384  * cpuhp_setup_state_multi().
385  */
386 static inline int cpuhp_state_add_instance(enum cpuhp_state state,
387 					   struct hlist_node *node)
388 {
389 	return __cpuhp_state_add_instance(state, node, true);
390 }
391 
392 /**
393  * cpuhp_state_add_instance_nocalls - Add an instance for a state without
394  *                                    invoking the startup callback.
395  * @state:	The state for which the instance is installed
396  * @node:	The node for this individual state.
397  *
398  * Installs the instance for the @state. The @state must have been earlier
399  * marked as multi-instance by cpuhp_setup_state_multi. NOP if SMP=n or
400  * HOTPLUG_CPU=n.
401  */
402 static inline int cpuhp_state_add_instance_nocalls(enum cpuhp_state state,
403 						   struct hlist_node *node)
404 {
405 	return __cpuhp_state_add_instance(state, node, false);
406 }
407 
408 /**
409  * cpuhp_state_add_instance_nocalls_cpuslocked - Add an instance for a state
410  *						 without invoking the startup
411  *						 callback from a cpus_read_lock()
412  *						 held region.
413  * @state:	The state for which the instance is installed
414  * @node:	The node for this individual state.
415  *
416  * Same as cpuhp_state_add_instance_nocalls() except that it must be
417  * invoked from within a cpus_read_lock() held region.
418  */
419 static inline int
420 cpuhp_state_add_instance_nocalls_cpuslocked(enum cpuhp_state state,
421 					    struct hlist_node *node)
422 {
423 	return __cpuhp_state_add_instance_cpuslocked(state, node, false);
424 }
425 
426 void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
427 void __cpuhp_remove_state_cpuslocked(enum cpuhp_state state, bool invoke);
428 
429 /**
430  * cpuhp_remove_state - Remove hotplug state callbacks and invoke the teardown
431  * @state:	The state for which the calls are removed
432  *
433  * Removes the callback functions and invokes the teardown callback on
434  * the online cpus which have already reached the @state.
435  */
436 static inline void cpuhp_remove_state(enum cpuhp_state state)
437 {
438 	__cpuhp_remove_state(state, true);
439 }
440 
441 /**
442  * cpuhp_remove_state_nocalls - Remove hotplug state callbacks without invoking
443  *				the teardown callback
444  * @state:	The state for which the calls are removed
445  */
446 static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state)
447 {
448 	__cpuhp_remove_state(state, false);
449 }
450 
451 /**
452  * cpuhp_remove_state_nocalls_cpuslocked - Remove hotplug state callbacks without invoking
453  *					   teardown from a cpus_read_lock() held region.
454  * @state:	The state for which the calls are removed
455  *
456  * Same as cpuhp_remove_state nocalls() except that it must be invoked
457  * from within a cpus_read_lock() held region.
458  */
459 static inline void cpuhp_remove_state_nocalls_cpuslocked(enum cpuhp_state state)
460 {
461 	__cpuhp_remove_state_cpuslocked(state, false);
462 }
463 
464 /**
465  * cpuhp_remove_multi_state - Remove hotplug multi state callback
466  * @state:	The state for which the calls are removed
467  *
468  * Removes the callback functions from a multi state. This is the reverse of
469  * cpuhp_setup_state_multi(). All instances should have been removed before
470  * invoking this function.
471  */
472 static inline void cpuhp_remove_multi_state(enum cpuhp_state state)
473 {
474 	__cpuhp_remove_state(state, false);
475 }
476 
477 int __cpuhp_state_remove_instance(enum cpuhp_state state,
478 				  struct hlist_node *node, bool invoke);
479 
480 /**
481  * cpuhp_state_remove_instance - Remove hotplug instance from state and invoke
482  *                               the teardown callback
483  * @state:	The state from which the instance is removed
484  * @node:	The node for this individual state.
485  *
486  * Removes the instance and invokes the teardown callback on the online cpus
487  * which have already reached @state.
488  */
489 static inline int cpuhp_state_remove_instance(enum cpuhp_state state,
490 					      struct hlist_node *node)
491 {
492 	return __cpuhp_state_remove_instance(state, node, true);
493 }
494 
495 /**
496  * cpuhp_state_remove_instance_nocalls - Remove hotplug instance from state
497  *					 without invoking the teardown callback
498  * @state:	The state from which the instance is removed
499  * @node:	The node for this individual state.
500  *
501  * Removes the instance without invoking the teardown callback.
502  */
503 static inline int cpuhp_state_remove_instance_nocalls(enum cpuhp_state state,
504 						      struct hlist_node *node)
505 {
506 	return __cpuhp_state_remove_instance(state, node, false);
507 }
508 
509 #ifdef CONFIG_SMP
510 void cpuhp_online_idle(enum cpuhp_state state);
511 #else
512 static inline void cpuhp_online_idle(enum cpuhp_state state) { }
513 #endif
514 
515 #endif
516