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_BP_PREPARE_DYN or CPUHP_AP_ONLINE_DYN 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_MCE_DEAD, 70 CPUHP_VIRT_NET_DEAD, 71 CPUHP_IBMVNIC_DEAD, 72 CPUHP_SLUB_DEAD, 73 CPUHP_DEBUG_OBJ_DEAD, 74 CPUHP_MM_WRITEBACK_DEAD, 75 CPUHP_MM_VMSTAT_DEAD, 76 CPUHP_SOFTIRQ_DEAD, 77 CPUHP_NET_MVNETA_DEAD, 78 CPUHP_CPUIDLE_DEAD, 79 CPUHP_ARM64_FPSIMD_DEAD, 80 CPUHP_ARM_OMAP_WAKE_DEAD, 81 CPUHP_IRQ_POLL_DEAD, 82 CPUHP_BLOCK_SOFTIRQ_DEAD, 83 CPUHP_BIO_DEAD, 84 CPUHP_ACPI_CPUDRV_DEAD, 85 CPUHP_S390_PFAULT_DEAD, 86 CPUHP_BLK_MQ_DEAD, 87 CPUHP_FS_BUFF_DEAD, 88 CPUHP_PRINTK_DEAD, 89 CPUHP_MM_MEMCQ_DEAD, 90 CPUHP_PERCPU_CNT_DEAD, 91 CPUHP_RADIX_DEAD, 92 CPUHP_PAGE_ALLOC, 93 CPUHP_NET_DEV_DEAD, 94 CPUHP_PCI_XGENE_DEAD, 95 CPUHP_IOMMU_IOVA_DEAD, 96 CPUHP_AP_ARM_CACHE_B15_RAC_DEAD, 97 CPUHP_PADATA_DEAD, 98 CPUHP_AP_DTPM_CPU_DEAD, 99 CPUHP_RANDOM_PREPARE, 100 CPUHP_WORKQUEUE_PREP, 101 CPUHP_POWER_NUMA_PREPARE, 102 CPUHP_HRTIMERS_PREPARE, 103 CPUHP_PROFILE_PREPARE, 104 CPUHP_X2APIC_PREPARE, 105 CPUHP_SMPCFD_PREPARE, 106 CPUHP_RELAY_PREPARE, 107 CPUHP_MD_RAID5_PREPARE, 108 CPUHP_RCUTREE_PREP, 109 CPUHP_CPUIDLE_COUPLED_PREPARE, 110 CPUHP_POWERPC_PMAC_PREPARE, 111 CPUHP_POWERPC_MMU_CTX_PREPARE, 112 CPUHP_XEN_PREPARE, 113 CPUHP_XEN_EVTCHN_PREPARE, 114 CPUHP_ARM_SHMOBILE_SCU_PREPARE, 115 CPUHP_SH_SH3X_PREPARE, 116 CPUHP_TOPOLOGY_PREPARE, 117 CPUHP_NET_IUCV_PREPARE, 118 CPUHP_ARM_BL_PREPARE, 119 CPUHP_TRACE_RB_PREPARE, 120 CPUHP_MM_ZS_PREPARE, 121 CPUHP_MM_ZSWP_POOL_PREPARE, 122 CPUHP_KVM_PPC_BOOK3S_PREPARE, 123 CPUHP_ZCOMP_PREPARE, 124 CPUHP_TIMERS_PREPARE, 125 CPUHP_MIPS_SOC_PREPARE, 126 CPUHP_BP_PREPARE_DYN, 127 CPUHP_BP_PREPARE_DYN_END = CPUHP_BP_PREPARE_DYN + 20, 128 CPUHP_BP_KICK_AP, 129 CPUHP_BRINGUP_CPU, 130 131 /* 132 * STARTING section invoked on the hotplugged CPU in low level 133 * bringup and teardown code. 134 */ 135 CPUHP_AP_IDLE_DEAD, 136 CPUHP_AP_OFFLINE, 137 CPUHP_AP_CACHECTRL_STARTING, 138 CPUHP_AP_SCHED_STARTING, 139 CPUHP_AP_RCUTREE_DYING, 140 CPUHP_AP_CPU_PM_STARTING, 141 CPUHP_AP_IRQ_GIC_STARTING, 142 CPUHP_AP_IRQ_HIP04_STARTING, 143 CPUHP_AP_IRQ_APPLE_AIC_STARTING, 144 CPUHP_AP_IRQ_ARMADA_XP_STARTING, 145 CPUHP_AP_IRQ_BCM2836_STARTING, 146 CPUHP_AP_IRQ_MIPS_GIC_STARTING, 147 CPUHP_AP_IRQ_LOONGARCH_STARTING, 148 CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING, 149 CPUHP_AP_ARM_MVEBU_COHERENCY, 150 CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING, 151 CPUHP_AP_PERF_X86_STARTING, 152 CPUHP_AP_PERF_X86_AMD_IBS_STARTING, 153 CPUHP_AP_PERF_X86_CSTATE_STARTING, 154 CPUHP_AP_PERF_XTENSA_STARTING, 155 CPUHP_AP_ARM_VFP_STARTING, 156 CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING, 157 CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING, 158 CPUHP_AP_PERF_ARM_ACPI_STARTING, 159 CPUHP_AP_PERF_ARM_STARTING, 160 CPUHP_AP_PERF_RISCV_STARTING, 161 CPUHP_AP_ARM_L2X0_STARTING, 162 CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING, 163 CPUHP_AP_ARM_ARCH_TIMER_STARTING, 164 CPUHP_AP_ARM_ARCH_TIMER_EVTSTRM_STARTING, 165 CPUHP_AP_ARM_GLOBAL_TIMER_STARTING, 166 CPUHP_AP_JCORE_TIMER_STARTING, 167 CPUHP_AP_ARM_TWD_STARTING, 168 CPUHP_AP_QCOM_TIMER_STARTING, 169 CPUHP_AP_TEGRA_TIMER_STARTING, 170 CPUHP_AP_ARMADA_TIMER_STARTING, 171 CPUHP_AP_MIPS_GIC_TIMER_STARTING, 172 CPUHP_AP_ARC_TIMER_STARTING, 173 CPUHP_AP_RISCV_TIMER_STARTING, 174 CPUHP_AP_CLINT_TIMER_STARTING, 175 CPUHP_AP_CSKY_TIMER_STARTING, 176 CPUHP_AP_TI_GP_TIMER_STARTING, 177 CPUHP_AP_HYPERV_TIMER_STARTING, 178 /* Must be the last timer callback */ 179 CPUHP_AP_DUMMY_TIMER_STARTING, 180 CPUHP_AP_ARM_XEN_STARTING, 181 CPUHP_AP_ARM_XEN_RUNSTATE_STARTING, 182 CPUHP_AP_ARM_CORESIGHT_STARTING, 183 CPUHP_AP_ARM_CORESIGHT_CTI_STARTING, 184 CPUHP_AP_ARM64_ISNDEP_STARTING, 185 CPUHP_AP_SMPCFD_DYING, 186 CPUHP_AP_HRTIMERS_DYING, 187 CPUHP_AP_TICK_DYING, 188 CPUHP_AP_X86_TBOOT_DYING, 189 CPUHP_AP_ARM_CACHE_B15_RAC_DYING, 190 CPUHP_AP_ONLINE, 191 CPUHP_TEARDOWN_CPU, 192 193 /* Online section invoked on the hotplugged CPU from the hotplug thread */ 194 CPUHP_AP_ONLINE_IDLE, 195 CPUHP_AP_HYPERV_ONLINE, 196 CPUHP_AP_KVM_ONLINE, 197 CPUHP_AP_SCHED_WAIT_EMPTY, 198 CPUHP_AP_SMPBOOT_THREADS, 199 CPUHP_AP_IRQ_AFFINITY_ONLINE, 200 CPUHP_AP_BLK_MQ_ONLINE, 201 CPUHP_AP_ARM_MVEBU_SYNC_CLOCKS, 202 CPUHP_AP_X86_INTEL_EPB_ONLINE, 203 CPUHP_AP_PERF_ONLINE, 204 CPUHP_AP_PERF_X86_ONLINE, 205 CPUHP_AP_PERF_X86_UNCORE_ONLINE, 206 CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE, 207 CPUHP_AP_PERF_X86_AMD_POWER_ONLINE, 208 CPUHP_AP_PERF_X86_RAPL_ONLINE, 209 CPUHP_AP_PERF_X86_CSTATE_ONLINE, 210 CPUHP_AP_PERF_S390_CF_ONLINE, 211 CPUHP_AP_PERF_S390_SF_ONLINE, 212 CPUHP_AP_PERF_ARM_CCI_ONLINE, 213 CPUHP_AP_PERF_ARM_CCN_ONLINE, 214 CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE, 215 CPUHP_AP_PERF_ARM_HISI_DDRC_ONLINE, 216 CPUHP_AP_PERF_ARM_HISI_HHA_ONLINE, 217 CPUHP_AP_PERF_ARM_HISI_L3_ONLINE, 218 CPUHP_AP_PERF_ARM_HISI_PA_ONLINE, 219 CPUHP_AP_PERF_ARM_HISI_SLLC_ONLINE, 220 CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE, 221 CPUHP_AP_PERF_ARM_HNS3_PMU_ONLINE, 222 CPUHP_AP_PERF_ARM_L2X0_ONLINE, 223 CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE, 224 CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, 225 CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE, 226 CPUHP_AP_PERF_ARM_CAVIUM_TX2_UNCORE_ONLINE, 227 CPUHP_AP_PERF_ARM_MARVELL_CN10K_DDR_ONLINE, 228 CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE, 229 CPUHP_AP_PERF_POWERPC_CORE_IMC_ONLINE, 230 CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE, 231 CPUHP_AP_PERF_POWERPC_TRACE_IMC_ONLINE, 232 CPUHP_AP_PERF_POWERPC_HV_24x7_ONLINE, 233 CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE, 234 CPUHP_AP_PERF_CSKY_ONLINE, 235 CPUHP_AP_TMIGR_ONLINE, 236 CPUHP_AP_WATCHDOG_ONLINE, 237 CPUHP_AP_WORKQUEUE_ONLINE, 238 CPUHP_AP_RANDOM_ONLINE, 239 CPUHP_AP_RCUTREE_ONLINE, 240 CPUHP_AP_BASE_CACHEINFO_ONLINE, 241 CPUHP_AP_ONLINE_DYN, 242 CPUHP_AP_ONLINE_DYN_END = CPUHP_AP_ONLINE_DYN + 40, 243 CPUHP_AP_X86_HPET_ONLINE, 244 CPUHP_AP_X86_KVM_CLK_ONLINE, 245 CPUHP_AP_ACTIVE, 246 CPUHP_ONLINE, 247}; 248 249int __cpuhp_setup_state(enum cpuhp_state state, const char *name, bool invoke, 250 int (*startup)(unsigned int cpu), 251 int (*teardown)(unsigned int cpu), bool multi_instance); 252 253int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, const char *name, 254 bool invoke, 255 int (*startup)(unsigned int cpu), 256 int (*teardown)(unsigned int cpu), 257 bool multi_instance); 258/** 259 * cpuhp_setup_state - Setup hotplug state callbacks with calling the @startup 260 * callback 261 * @state: The state for which the calls are installed 262 * @name: Name of the callback (will be used in debug output) 263 * @startup: startup callback function or NULL if not required 264 * @teardown: teardown callback function or NULL if not required 265 * 266 * Installs the callback functions and invokes the @startup callback on 267 * the online cpus which have already reached the @state. 268 */ 269static inline int cpuhp_setup_state(enum cpuhp_state state, 270 const char *name, 271 int (*startup)(unsigned int cpu), 272 int (*teardown)(unsigned int cpu)) 273{ 274 return __cpuhp_setup_state(state, name, true, startup, teardown, false); 275} 276 277/** 278 * cpuhp_setup_state_cpuslocked - Setup hotplug state callbacks with calling 279 * @startup callback from a cpus_read_lock() 280 * held region 281 * @state: The state for which the calls are installed 282 * @name: Name of the callback (will be used in debug output) 283 * @startup: startup callback function or NULL if not required 284 * @teardown: teardown callback function or NULL if not required 285 * 286 * Same as cpuhp_setup_state() except that it must be invoked from within a 287 * cpus_read_lock() held region. 288 */ 289static inline int cpuhp_setup_state_cpuslocked(enum cpuhp_state state, 290 const char *name, 291 int (*startup)(unsigned int cpu), 292 int (*teardown)(unsigned int cpu)) 293{ 294 return __cpuhp_setup_state_cpuslocked(state, name, true, startup, 295 teardown, false); 296} 297 298/** 299 * cpuhp_setup_state_nocalls - Setup hotplug state callbacks without calling the 300 * @startup callback 301 * @state: The state for which the calls are installed 302 * @name: Name of the callback. 303 * @startup: startup callback function or NULL if not required 304 * @teardown: teardown callback function or NULL if not required 305 * 306 * Same as cpuhp_setup_state() except that the @startup callback is not 307 * invoked during installation. NOP if SMP=n or HOTPLUG_CPU=n. 308 */ 309static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state, 310 const char *name, 311 int (*startup)(unsigned int cpu), 312 int (*teardown)(unsigned int cpu)) 313{ 314 return __cpuhp_setup_state(state, name, false, startup, teardown, 315 false); 316} 317 318/** 319 * cpuhp_setup_state_nocalls_cpuslocked - Setup hotplug state callbacks without 320 * invoking the @startup callback from 321 * a cpus_read_lock() held region 322 * callbacks 323 * @state: The state for which the calls are installed 324 * @name: Name of the callback. 325 * @startup: startup callback function or NULL if not required 326 * @teardown: teardown callback function or NULL if not required 327 * 328 * Same as cpuhp_setup_state_nocalls() except that it must be invoked from 329 * within a cpus_read_lock() held region. 330 */ 331static inline int cpuhp_setup_state_nocalls_cpuslocked(enum cpuhp_state state, 332 const char *name, 333 int (*startup)(unsigned int cpu), 334 int (*teardown)(unsigned int cpu)) 335{ 336 return __cpuhp_setup_state_cpuslocked(state, name, false, startup, 337 teardown, false); 338} 339 340/** 341 * cpuhp_setup_state_multi - Add callbacks for multi state 342 * @state: The state for which the calls are installed 343 * @name: Name of the callback. 344 * @startup: startup callback function or NULL if not required 345 * @teardown: teardown callback function or NULL if not required 346 * 347 * Sets the internal multi_instance flag and prepares a state to work as a multi 348 * instance callback. No callbacks are invoked at this point. The callbacks are 349 * invoked once an instance for this state are registered via 350 * cpuhp_state_add_instance() or cpuhp_state_add_instance_nocalls() 351 */ 352static inline int cpuhp_setup_state_multi(enum cpuhp_state state, 353 const char *name, 354 int (*startup)(unsigned int cpu, 355 struct hlist_node *node), 356 int (*teardown)(unsigned int cpu, 357 struct hlist_node *node)) 358{ 359 return __cpuhp_setup_state(state, name, false, 360 (void *) startup, 361 (void *) teardown, true); 362} 363 364int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node, 365 bool invoke); 366int __cpuhp_state_add_instance_cpuslocked(enum cpuhp_state state, 367 struct hlist_node *node, bool invoke); 368 369/** 370 * cpuhp_state_add_instance - Add an instance for a state and invoke startup 371 * callback. 372 * @state: The state for which the instance is installed 373 * @node: The node for this individual state. 374 * 375 * Installs the instance for the @state and invokes the registered startup 376 * callback on the online cpus which have already reached the @state. The 377 * @state must have been earlier marked as multi-instance by 378 * cpuhp_setup_state_multi(). 379 */ 380static inline int cpuhp_state_add_instance(enum cpuhp_state state, 381 struct hlist_node *node) 382{ 383 return __cpuhp_state_add_instance(state, node, true); 384} 385 386/** 387 * cpuhp_state_add_instance_nocalls - Add an instance for a state without 388 * invoking the startup callback. 389 * @state: The state for which the instance is installed 390 * @node: The node for this individual state. 391 * 392 * Installs the instance for the @state. The @state must have been earlier 393 * marked as multi-instance by cpuhp_setup_state_multi. NOP if SMP=n or 394 * HOTPLUG_CPU=n. 395 */ 396static inline int cpuhp_state_add_instance_nocalls(enum cpuhp_state state, 397 struct hlist_node *node) 398{ 399 return __cpuhp_state_add_instance(state, node, false); 400} 401 402/** 403 * cpuhp_state_add_instance_nocalls_cpuslocked - Add an instance for a state 404 * without invoking the startup 405 * callback from a cpus_read_lock() 406 * held region. 407 * @state: The state for which the instance is installed 408 * @node: The node for this individual state. 409 * 410 * Same as cpuhp_state_add_instance_nocalls() except that it must be 411 * invoked from within a cpus_read_lock() held region. 412 */ 413static inline int 414cpuhp_state_add_instance_nocalls_cpuslocked(enum cpuhp_state state, 415 struct hlist_node *node) 416{ 417 return __cpuhp_state_add_instance_cpuslocked(state, node, false); 418} 419 420void __cpuhp_remove_state(enum cpuhp_state state, bool invoke); 421void __cpuhp_remove_state_cpuslocked(enum cpuhp_state state, bool invoke); 422 423/** 424 * cpuhp_remove_state - Remove hotplug state callbacks and invoke the teardown 425 * @state: The state for which the calls are removed 426 * 427 * Removes the callback functions and invokes the teardown callback on 428 * the online cpus which have already reached the @state. 429 */ 430static inline void cpuhp_remove_state(enum cpuhp_state state) 431{ 432 __cpuhp_remove_state(state, true); 433} 434 435/** 436 * cpuhp_remove_state_nocalls - Remove hotplug state callbacks without invoking 437 * the teardown callback 438 * @state: The state for which the calls are removed 439 */ 440static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state) 441{ 442 __cpuhp_remove_state(state, false); 443} 444 445/** 446 * cpuhp_remove_state_nocalls_cpuslocked - Remove hotplug state callbacks without invoking 447 * teardown from a cpus_read_lock() held region. 448 * @state: The state for which the calls are removed 449 * 450 * Same as cpuhp_remove_state nocalls() except that it must be invoked 451 * from within a cpus_read_lock() held region. 452 */ 453static inline void cpuhp_remove_state_nocalls_cpuslocked(enum cpuhp_state state) 454{ 455 __cpuhp_remove_state_cpuslocked(state, false); 456} 457 458/** 459 * cpuhp_remove_multi_state - Remove hotplug multi state callback 460 * @state: The state for which the calls are removed 461 * 462 * Removes the callback functions from a multi state. This is the reverse of 463 * cpuhp_setup_state_multi(). All instances should have been removed before 464 * invoking this function. 465 */ 466static inline void cpuhp_remove_multi_state(enum cpuhp_state state) 467{ 468 __cpuhp_remove_state(state, false); 469} 470 471int __cpuhp_state_remove_instance(enum cpuhp_state state, 472 struct hlist_node *node, bool invoke); 473 474/** 475 * cpuhp_state_remove_instance - Remove hotplug instance from state and invoke 476 * the teardown callback 477 * @state: The state from which the instance is removed 478 * @node: The node for this individual state. 479 * 480 * Removes the instance and invokes the teardown callback on the online cpus 481 * which have already reached @state. 482 */ 483static inline int cpuhp_state_remove_instance(enum cpuhp_state state, 484 struct hlist_node *node) 485{ 486 return __cpuhp_state_remove_instance(state, node, true); 487} 488 489/** 490 * cpuhp_state_remove_instance_nocalls - Remove hotplug instance from state 491 * without invoking 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 without invoking the teardown callback. 496 */ 497static inline int cpuhp_state_remove_instance_nocalls(enum cpuhp_state state, 498 struct hlist_node *node) 499{ 500 return __cpuhp_state_remove_instance(state, node, false); 501} 502 503#ifdef CONFIG_SMP 504void cpuhp_online_idle(enum cpuhp_state state); 505#else 506static inline void cpuhp_online_idle(enum cpuhp_state state) { } 507#endif 508 509struct task_struct; 510 511void cpuhp_ap_sync_alive(void); 512void arch_cpuhp_sync_state_poll(void); 513void arch_cpuhp_cleanup_kick_cpu(unsigned int cpu); 514int arch_cpuhp_kick_ap_alive(unsigned int cpu, struct task_struct *tidle); 515bool arch_cpuhp_init_parallel_bringup(void); 516 517#ifdef CONFIG_HOTPLUG_CORE_SYNC_DEAD 518void cpuhp_ap_report_dead(void); 519void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu); 520#else 521static inline void cpuhp_ap_report_dead(void) { } 522static inline void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu) { } 523#endif 524 525#endif 526