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 515