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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_IBMVNIC_DEAD,
73 CPUHP_SLUB_DEAD,
74 CPUHP_DEBUG_OBJ_DEAD,
75 CPUHP_MM_WRITEBACK_DEAD,
76 /* Must be after CPUHP_MM_VMSTAT_DEAD */
77 CPUHP_MM_DEMOTION_DEAD,
78 CPUHP_MM_VMSTAT_DEAD,
79 CPUHP_SOFTIRQ_DEAD,
80 CPUHP_NET_MVNETA_DEAD,
81 CPUHP_CPUIDLE_DEAD,
82 CPUHP_ARM64_FPSIMD_DEAD,
83 CPUHP_ARM_OMAP_WAKE_DEAD,
84 CPUHP_IRQ_POLL_DEAD,
85 CPUHP_BLOCK_SOFTIRQ_DEAD,
86 CPUHP_BIO_DEAD,
87 CPUHP_ACPI_CPUDRV_DEAD,
88 CPUHP_S390_PFAULT_DEAD,
89 CPUHP_BLK_MQ_DEAD,
90 CPUHP_FS_BUFF_DEAD,
91 CPUHP_PRINTK_DEAD,
92 CPUHP_MM_MEMCQ_DEAD,
93 CPUHP_XFS_DEAD,
94 CPUHP_PERCPU_CNT_DEAD,
95 CPUHP_RADIX_DEAD,
96 CPUHP_PAGE_ALLOC,
97 CPUHP_NET_DEV_DEAD,
98 CPUHP_PCI_XGENE_DEAD,
99 CPUHP_IOMMU_IOVA_DEAD,
100 CPUHP_LUSTRE_CFS_DEAD,
101 CPUHP_AP_ARM_CACHE_B15_RAC_DEAD,
102 CPUHP_PADATA_DEAD,
103 CPUHP_AP_DTPM_CPU_DEAD,
104 CPUHP_RANDOM_PREPARE,
105 CPUHP_WORKQUEUE_PREP,
106 CPUHP_POWER_NUMA_PREPARE,
107 CPUHP_HRTIMERS_PREPARE,
108 CPUHP_PROFILE_PREPARE,
109 CPUHP_X2APIC_PREPARE,
110 CPUHP_SMPCFD_PREPARE,
111 CPUHP_RELAY_PREPARE,
112 CPUHP_SLAB_PREPARE,
113 CPUHP_MD_RAID5_PREPARE,
114 CPUHP_RCUTREE_PREP,
115 CPUHP_CPUIDLE_COUPLED_PREPARE,
116 CPUHP_POWERPC_PMAC_PREPARE,
117 CPUHP_POWERPC_MMU_CTX_PREPARE,
118 CPUHP_XEN_PREPARE,
119 CPUHP_XEN_EVTCHN_PREPARE,
120 CPUHP_ARM_SHMOBILE_SCU_PREPARE,
121 CPUHP_SH_SH3X_PREPARE,
122 CPUHP_NET_FLOW_PREPARE,
123 CPUHP_TOPOLOGY_PREPARE,
124 CPUHP_NET_IUCV_PREPARE,
125 CPUHP_ARM_BL_PREPARE,
126 CPUHP_TRACE_RB_PREPARE,
127 CPUHP_MM_ZS_PREPARE,
128 CPUHP_MM_ZSWP_MEM_PREPARE,
129 CPUHP_MM_ZSWP_POOL_PREPARE,
130 CPUHP_KVM_PPC_BOOK3S_PREPARE,
131 CPUHP_ZCOMP_PREPARE,
132 CPUHP_TIMERS_PREPARE,
133 CPUHP_MIPS_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_CACHECTRL_STARTING,
145 CPUHP_AP_SCHED_STARTING,
146 CPUHP_AP_RCUTREE_DYING,
147 CPUHP_AP_CPU_PM_STARTING,
148 CPUHP_AP_IRQ_GIC_STARTING,
149 CPUHP_AP_IRQ_HIP04_STARTING,
150 CPUHP_AP_IRQ_APPLE_AIC_STARTING,
151 CPUHP_AP_IRQ_ARMADA_XP_STARTING,
152 CPUHP_AP_IRQ_BCM2836_STARTING,
153 CPUHP_AP_IRQ_MIPS_GIC_STARTING,
154 CPUHP_AP_IRQ_RISCV_STARTING,
155 CPUHP_AP_IRQ_LOONGARCH_STARTING,
156 CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING,
157 CPUHP_AP_ARM_MVEBU_COHERENCY,
158 CPUHP_AP_MICROCODE_LOADER,
159 CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING,
160 CPUHP_AP_PERF_X86_STARTING,
161 CPUHP_AP_PERF_X86_AMD_IBS_STARTING,
162 CPUHP_AP_PERF_X86_CQM_STARTING,
163 CPUHP_AP_PERF_X86_CSTATE_STARTING,
164 CPUHP_AP_PERF_XTENSA_STARTING,
165 CPUHP_AP_MIPS_OP_LOONGSON3_STARTING,
166 CPUHP_AP_ARM_SDEI_STARTING,
167 CPUHP_AP_ARM_VFP_STARTING,
168 CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING,
169 CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING,
170 CPUHP_AP_PERF_ARM_ACPI_STARTING,
171 CPUHP_AP_PERF_ARM_STARTING,
172 CPUHP_AP_PERF_RISCV_STARTING,
173 CPUHP_AP_ARM_L2X0_STARTING,
174 CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
175 CPUHP_AP_ARM_ARCH_TIMER_STARTING,
176 CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
177 CPUHP_AP_JCORE_TIMER_STARTING,
178 CPUHP_AP_ARM_TWD_STARTING,
179 CPUHP_AP_QCOM_TIMER_STARTING,
180 CPUHP_AP_TEGRA_TIMER_STARTING,
181 CPUHP_AP_ARMADA_TIMER_STARTING,
182 CPUHP_AP_MARCO_TIMER_STARTING,
183 CPUHP_AP_MIPS_GIC_TIMER_STARTING,
184 CPUHP_AP_ARC_TIMER_STARTING,
185 CPUHP_AP_RISCV_TIMER_STARTING,
186 CPUHP_AP_CLINT_TIMER_STARTING,
187 CPUHP_AP_CSKY_TIMER_STARTING,
188 CPUHP_AP_TI_GP_TIMER_STARTING,
189 CPUHP_AP_HYPERV_TIMER_STARTING,
190 CPUHP_AP_KVM_STARTING,
191 CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
192 CPUHP_AP_KVM_ARM_VGIC_STARTING,
193 CPUHP_AP_KVM_ARM_TIMER_STARTING,
194 /* Must be the last timer callback */
195 CPUHP_AP_DUMMY_TIMER_STARTING,
196 CPUHP_AP_ARM_XEN_STARTING,
197 CPUHP_AP_ARM_CORESIGHT_STARTING,
198 CPUHP_AP_ARM_CORESIGHT_CTI_STARTING,
199 CPUHP_AP_ARM64_ISNDEP_STARTING,
200 CPUHP_AP_SMPCFD_DYING,
201 CPUHP_AP_X86_TBOOT_DYING,
202 CPUHP_AP_ARM_CACHE_B15_RAC_DYING,
203 CPUHP_AP_ONLINE,
204 CPUHP_TEARDOWN_CPU,
205
206 /* Online section invoked on the hotplugged CPU from the hotplug thread */
207 CPUHP_AP_ONLINE_IDLE,
208 CPUHP_AP_SCHED_WAIT_EMPTY,
209 CPUHP_AP_SMPBOOT_THREADS,
210 CPUHP_AP_X86_VDSO_VMA_ONLINE,
211 CPUHP_AP_IRQ_AFFINITY_ONLINE,
212 CPUHP_AP_BLK_MQ_ONLINE,
213 CPUHP_AP_ARM_MVEBU_SYNC_CLOCKS,
214 CPUHP_AP_X86_INTEL_EPB_ONLINE,
215 CPUHP_AP_PERF_ONLINE,
216 CPUHP_AP_PERF_X86_ONLINE,
217 CPUHP_AP_PERF_X86_UNCORE_ONLINE,
218 CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE,
219 CPUHP_AP_PERF_X86_AMD_POWER_ONLINE,
220 CPUHP_AP_PERF_X86_RAPL_ONLINE,
221 CPUHP_AP_PERF_X86_CQM_ONLINE,
222 CPUHP_AP_PERF_X86_CSTATE_ONLINE,
223 CPUHP_AP_PERF_X86_IDXD_ONLINE,
224 CPUHP_AP_PERF_S390_CF_ONLINE,
225 CPUHP_AP_PERF_S390_SF_ONLINE,
226 CPUHP_AP_PERF_ARM_CCI_ONLINE,
227 CPUHP_AP_PERF_ARM_CCN_ONLINE,
228 CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE,
229 CPUHP_AP_PERF_ARM_HISI_DDRC_ONLINE,
230 CPUHP_AP_PERF_ARM_HISI_HHA_ONLINE,
231 CPUHP_AP_PERF_ARM_HISI_L3_ONLINE,
232 CPUHP_AP_PERF_ARM_HISI_PA_ONLINE,
233 CPUHP_AP_PERF_ARM_HISI_SLLC_ONLINE,
234 CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE,
235 CPUHP_AP_PERF_ARM_HNS3_PMU_ONLINE,
236 CPUHP_AP_PERF_ARM_L2X0_ONLINE,
237 CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
238 CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE,
239 CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE,
240 CPUHP_AP_PERF_ARM_CAVIUM_TX2_UNCORE_ONLINE,
241 CPUHP_AP_PERF_ARM_MARVELL_CN10K_DDR_ONLINE,
242 CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE,
243 CPUHP_AP_PERF_POWERPC_CORE_IMC_ONLINE,
244 CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE,
245 CPUHP_AP_PERF_POWERPC_TRACE_IMC_ONLINE,
246 CPUHP_AP_PERF_POWERPC_HV_24x7_ONLINE,
247 CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE,
248 CPUHP_AP_PERF_CSKY_ONLINE,
249 CPUHP_AP_WATCHDOG_ONLINE,
250 CPUHP_AP_WORKQUEUE_ONLINE,
251 CPUHP_AP_RANDOM_ONLINE,
252 CPUHP_AP_RCUTREE_ONLINE,
253 CPUHP_AP_BASE_CACHEINFO_ONLINE,
254 CPUHP_AP_ONLINE_DYN,
255 CPUHP_AP_ONLINE_DYN_END = CPUHP_AP_ONLINE_DYN + 30,
256 /* Must be after CPUHP_AP_ONLINE_DYN for node_states[N_CPU] update */
257 CPUHP_AP_MM_DEMOTION_ONLINE,
258 CPUHP_AP_X86_HPET_ONLINE,
259 CPUHP_AP_X86_KVM_CLK_ONLINE,
260 CPUHP_AP_ACTIVE,
261 CPUHP_ONLINE,
262};
263
264int __cpuhp_setup_state(enum cpuhp_state state, const char *name, bool invoke,
265 int (*startup)(unsigned int cpu),
266 int (*teardown)(unsigned int cpu), bool multi_instance);
267
268int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, const char *name,
269 bool invoke,
270 int (*startup)(unsigned int cpu),
271 int (*teardown)(unsigned int cpu),
272 bool multi_instance);
273/**
274 * cpuhp_setup_state - Setup hotplug state callbacks with calling the @startup
275 * callback
276 * @state: The state for which the calls are installed
277 * @name: Name of the callback (will be used in debug output)
278 * @startup: startup callback function or NULL if not required
279 * @teardown: teardown callback function or NULL if not required
280 *
281 * Installs the callback functions and invokes the @startup callback on
282 * the online cpus which have already reached the @state.
283 */
284static inline int cpuhp_setup_state(enum cpuhp_state state,
285 const char *name,
286 int (*startup)(unsigned int cpu),
287 int (*teardown)(unsigned int cpu))
288{
289 return __cpuhp_setup_state(state, name, true, startup, teardown, false);
290}
291
292/**
293 * cpuhp_setup_state_cpuslocked - Setup hotplug state callbacks with calling
294 * @startup callback from a cpus_read_lock()
295 * held region
296 * @state: The state for which the calls are installed
297 * @name: Name of the callback (will be used in debug output)
298 * @startup: startup callback function or NULL if not required
299 * @teardown: teardown callback function or NULL if not required
300 *
301 * Same as cpuhp_setup_state() except that it must be invoked from within a
302 * cpus_read_lock() held region.
303 */
304static inline int cpuhp_setup_state_cpuslocked(enum cpuhp_state state,
305 const char *name,
306 int (*startup)(unsigned int cpu),
307 int (*teardown)(unsigned int cpu))
308{
309 return __cpuhp_setup_state_cpuslocked(state, name, true, startup,
310 teardown, false);
311}
312
313/**
314 * cpuhp_setup_state_nocalls - Setup hotplug state callbacks without calling the
315 * @startup callback
316 * @state: The state for which the calls are installed
317 * @name: Name of the callback.
318 * @startup: startup callback function or NULL if not required
319 * @teardown: teardown callback function or NULL if not required
320 *
321 * Same as cpuhp_setup_state() except that the @startup callback is not
322 * invoked during installation. NOP if SMP=n or HOTPLUG_CPU=n.
323 */
324static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state,
325 const char *name,
326 int (*startup)(unsigned int cpu),
327 int (*teardown)(unsigned int cpu))
328{
329 return __cpuhp_setup_state(state, name, false, startup, teardown,
330 false);
331}
332
333/**
334 * cpuhp_setup_state_nocalls_cpuslocked - Setup hotplug state callbacks without
335 * invoking the @startup callback from
336 * a cpus_read_lock() held region
337 * callbacks
338 * @state: The state for which the calls are installed
339 * @name: Name of the callback.
340 * @startup: startup callback function or NULL if not required
341 * @teardown: teardown callback function or NULL if not required
342 *
343 * Same as cpuhp_setup_state_nocalls() except that it must be invoked from
344 * within a cpus_read_lock() held region.
345 */
346static inline int cpuhp_setup_state_nocalls_cpuslocked(enum cpuhp_state state,
347 const char *name,
348 int (*startup)(unsigned int cpu),
349 int (*teardown)(unsigned int cpu))
350{
351 return __cpuhp_setup_state_cpuslocked(state, name, false, startup,
352 teardown, false);
353}
354
355/**
356 * cpuhp_setup_state_multi - Add callbacks for multi state
357 * @state: The state for which the calls are installed
358 * @name: Name of the callback.
359 * @startup: startup callback function or NULL if not required
360 * @teardown: teardown callback function or NULL if not required
361 *
362 * Sets the internal multi_instance flag and prepares a state to work as a multi
363 * instance callback. No callbacks are invoked at this point. The callbacks are
364 * invoked once an instance for this state are registered via
365 * cpuhp_state_add_instance() or cpuhp_state_add_instance_nocalls()
366 */
367static inline int cpuhp_setup_state_multi(enum cpuhp_state state,
368 const char *name,
369 int (*startup)(unsigned int cpu,
370 struct hlist_node *node),
371 int (*teardown)(unsigned int cpu,
372 struct hlist_node *node))
373{
374 return __cpuhp_setup_state(state, name, false,
375 (void *) startup,
376 (void *) teardown, true);
377}
378
379int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node,
380 bool invoke);
381int __cpuhp_state_add_instance_cpuslocked(enum cpuhp_state state,
382 struct hlist_node *node, bool invoke);
383
384/**
385 * cpuhp_state_add_instance - Add an instance for a state and invoke startup
386 * callback.
387 * @state: The state for which the instance is installed
388 * @node: The node for this individual state.
389 *
390 * Installs the instance for the @state and invokes the registered startup
391 * callback on the online cpus which have already reached the @state. The
392 * @state must have been earlier marked as multi-instance by
393 * cpuhp_setup_state_multi().
394 */
395static inline int cpuhp_state_add_instance(enum cpuhp_state state,
396 struct hlist_node *node)
397{
398 return __cpuhp_state_add_instance(state, node, true);
399}
400
401/**
402 * cpuhp_state_add_instance_nocalls - Add an instance for a state without
403 * invoking the startup callback.
404 * @state: The state for which the instance is installed
405 * @node: The node for this individual state.
406 *
407 * Installs the instance for the @state. The @state must have been earlier
408 * marked as multi-instance by cpuhp_setup_state_multi. NOP if SMP=n or
409 * HOTPLUG_CPU=n.
410 */
411static inline int cpuhp_state_add_instance_nocalls(enum cpuhp_state state,
412 struct hlist_node *node)
413{
414 return __cpuhp_state_add_instance(state, node, false);
415}
416
417/**
418 * cpuhp_state_add_instance_nocalls_cpuslocked - Add an instance for a state
419 * without invoking the startup
420 * callback from a cpus_read_lock()
421 * held region.
422 * @state: The state for which the instance is installed
423 * @node: The node for this individual state.
424 *
425 * Same as cpuhp_state_add_instance_nocalls() except that it must be
426 * invoked from within a cpus_read_lock() held region.
427 */
428static inline int
429cpuhp_state_add_instance_nocalls_cpuslocked(enum cpuhp_state state,
430 struct hlist_node *node)
431{
432 return __cpuhp_state_add_instance_cpuslocked(state, node, false);
433}
434
435void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
436void __cpuhp_remove_state_cpuslocked(enum cpuhp_state state, bool invoke);
437
438/**
439 * cpuhp_remove_state - Remove hotplug state callbacks and invoke the teardown
440 * @state: The state for which the calls are removed
441 *
442 * Removes the callback functions and invokes the teardown callback on
443 * the online cpus which have already reached the @state.
444 */
445static inline void cpuhp_remove_state(enum cpuhp_state state)
446{
447 __cpuhp_remove_state(state, true);
448}
449
450/**
451 * cpuhp_remove_state_nocalls - Remove hotplug state callbacks without invoking
452 * the teardown callback
453 * @state: The state for which the calls are removed
454 */
455static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state)
456{
457 __cpuhp_remove_state(state, false);
458}
459
460/**
461 * cpuhp_remove_state_nocalls_cpuslocked - Remove hotplug state callbacks without invoking
462 * teardown from a cpus_read_lock() held region.
463 * @state: The state for which the calls are removed
464 *
465 * Same as cpuhp_remove_state nocalls() except that it must be invoked
466 * from within a cpus_read_lock() held region.
467 */
468static inline void cpuhp_remove_state_nocalls_cpuslocked(enum cpuhp_state state)
469{
470 __cpuhp_remove_state_cpuslocked(state, false);
471}
472
473/**
474 * cpuhp_remove_multi_state - Remove hotplug multi state callback
475 * @state: The state for which the calls are removed
476 *
477 * Removes the callback functions from a multi state. This is the reverse of
478 * cpuhp_setup_state_multi(). All instances should have been removed before
479 * invoking this function.
480 */
481static inline void cpuhp_remove_multi_state(enum cpuhp_state state)
482{
483 __cpuhp_remove_state(state, false);
484}
485
486int __cpuhp_state_remove_instance(enum cpuhp_state state,
487 struct hlist_node *node, bool invoke);
488
489/**
490 * cpuhp_state_remove_instance - Remove hotplug instance from state and invoke
491 * the teardown callback
492 * @state: The state from which the instance is removed
493 * @node: The node for this individual state.
494 *
495 * Removes the instance and invokes the teardown callback on the online cpus
496 * which have already reached @state.
497 */
498static inline int cpuhp_state_remove_instance(enum cpuhp_state state,
499 struct hlist_node *node)
500{
501 return __cpuhp_state_remove_instance(state, node, true);
502}
503
504/**
505 * cpuhp_state_remove_instance_nocalls - Remove hotplug instance from state
506 * without invoking the teardown callback
507 * @state: The state from which the instance is removed
508 * @node: The node for this individual state.
509 *
510 * Removes the instance without invoking the teardown callback.
511 */
512static inline int cpuhp_state_remove_instance_nocalls(enum cpuhp_state state,
513 struct hlist_node *node)
514{
515 return __cpuhp_state_remove_instance(state, node, false);
516}
517
518#ifdef CONFIG_SMP
519void cpuhp_online_idle(enum cpuhp_state state);
520#else
521static inline void cpuhp_online_idle(enum cpuhp_state state) { }
522#endif
523
524#endif