1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * x86 SMP booting functions 4 * 5 * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk> 6 * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com> 7 * Copyright 2001 Andi Kleen, SuSE Labs. 8 * 9 * Much of the core SMP work is based on previous work by Thomas Radke, to 10 * whom a great many thanks are extended. 11 * 12 * Thanks to Intel for making available several different Pentium, 13 * Pentium Pro and Pentium-II/Xeon MP machines. 14 * Original development of Linux SMP code supported by Caldera. 15 * 16 * Fixes 17 * Felix Koop : NR_CPUS used properly 18 * Jose Renau : Handle single CPU case. 19 * Alan Cox : By repeated request 8) - Total BogoMIPS report. 20 * Greg Wright : Fix for kernel stacks panic. 21 * Erich Boleyn : MP v1.4 and additional changes. 22 * Matthias Sattler : Changes for 2.1 kernel map. 23 * Michel Lespinasse : Changes for 2.1 kernel map. 24 * Michael Chastain : Change trampoline.S to gnu as. 25 * Alan Cox : Dumb bug: 'B' step PPro's are fine 26 * Ingo Molnar : Added APIC timers, based on code 27 * from Jose Renau 28 * Ingo Molnar : various cleanups and rewrites 29 * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug. 30 * Maciej W. Rozycki : Bits for genuine 82489DX APICs 31 * Andi Kleen : Changed for SMP boot into long mode. 32 * Martin J. Bligh : Added support for multi-quad systems 33 * Dave Jones : Report invalid combinations of Athlon CPUs. 34 * Rusty Russell : Hacked into shape for new "hotplug" boot process. 35 * Andi Kleen : Converted to new state machine. 36 * Ashok Raj : CPU hotplug support 37 * Glauber Costa : i386 and x86_64 integration 38 */ 39 40 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 41 42 #include <linux/init.h> 43 #include <linux/smp.h> 44 #include <linux/export.h> 45 #include <linux/sched.h> 46 #include <linux/sched/topology.h> 47 #include <linux/sched/hotplug.h> 48 #include <linux/sched/task_stack.h> 49 #include <linux/percpu.h> 50 #include <linux/memblock.h> 51 #include <linux/err.h> 52 #include <linux/nmi.h> 53 #include <linux/tboot.h> 54 #include <linux/gfp.h> 55 #include <linux/cpuidle.h> 56 #include <linux/numa.h> 57 #include <linux/pgtable.h> 58 #include <linux/overflow.h> 59 #include <linux/syscore_ops.h> 60 61 #include <asm/acpi.h> 62 #include <asm/desc.h> 63 #include <asm/nmi.h> 64 #include <asm/irq.h> 65 #include <asm/realmode.h> 66 #include <asm/cpu.h> 67 #include <asm/numa.h> 68 #include <asm/tlbflush.h> 69 #include <asm/mtrr.h> 70 #include <asm/mwait.h> 71 #include <asm/apic.h> 72 #include <asm/io_apic.h> 73 #include <asm/fpu/internal.h> 74 #include <asm/setup.h> 75 #include <asm/uv/uv.h> 76 #include <linux/mc146818rtc.h> 77 #include <asm/i8259.h> 78 #include <asm/misc.h> 79 #include <asm/qspinlock.h> 80 #include <asm/intel-family.h> 81 #include <asm/cpu_device_id.h> 82 #include <asm/spec-ctrl.h> 83 #include <asm/hw_irq.h> 84 #include <asm/stackprotector.h> 85 86 #ifdef CONFIG_ACPI_CPPC_LIB 87 #include <acpi/cppc_acpi.h> 88 #endif 89 90 /* representing HT siblings of each logical CPU */ 91 DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map); 92 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map); 93 94 /* representing HT and core siblings of each logical CPU */ 95 DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map); 96 EXPORT_PER_CPU_SYMBOL(cpu_core_map); 97 98 /* representing HT, core, and die siblings of each logical CPU */ 99 DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_die_map); 100 EXPORT_PER_CPU_SYMBOL(cpu_die_map); 101 102 DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); 103 104 /* Per CPU bogomips and other parameters */ 105 DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info); 106 EXPORT_PER_CPU_SYMBOL(cpu_info); 107 108 /* Logical package management. We might want to allocate that dynamically */ 109 unsigned int __max_logical_packages __read_mostly; 110 EXPORT_SYMBOL(__max_logical_packages); 111 static unsigned int logical_packages __read_mostly; 112 static unsigned int logical_die __read_mostly; 113 114 /* Maximum number of SMT threads on any online core */ 115 int __read_mostly __max_smt_threads = 1; 116 117 /* Flag to indicate if a complete sched domain rebuild is required */ 118 bool x86_topology_update; 119 120 int arch_update_cpu_topology(void) 121 { 122 int retval = x86_topology_update; 123 124 x86_topology_update = false; 125 return retval; 126 } 127 128 static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip) 129 { 130 unsigned long flags; 131 132 spin_lock_irqsave(&rtc_lock, flags); 133 CMOS_WRITE(0xa, 0xf); 134 spin_unlock_irqrestore(&rtc_lock, flags); 135 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) = 136 start_eip >> 4; 137 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 138 start_eip & 0xf; 139 } 140 141 static inline void smpboot_restore_warm_reset_vector(void) 142 { 143 unsigned long flags; 144 145 /* 146 * Paranoid: Set warm reset code and vector here back 147 * to default values. 148 */ 149 spin_lock_irqsave(&rtc_lock, flags); 150 CMOS_WRITE(0, 0xf); 151 spin_unlock_irqrestore(&rtc_lock, flags); 152 153 *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0; 154 } 155 156 static void init_freq_invariance(bool secondary, bool cppc_ready); 157 158 /* 159 * Report back to the Boot Processor during boot time or to the caller processor 160 * during CPU online. 161 */ 162 static void smp_callin(void) 163 { 164 int cpuid; 165 166 /* 167 * If waken up by an INIT in an 82489DX configuration 168 * cpu_callout_mask guarantees we don't get here before 169 * an INIT_deassert IPI reaches our local APIC, so it is 170 * now safe to touch our local APIC. 171 */ 172 cpuid = smp_processor_id(); 173 174 /* 175 * the boot CPU has finished the init stage and is spinning 176 * on callin_map until we finish. We are free to set up this 177 * CPU, first the APIC. (this is probably redundant on most 178 * boards) 179 */ 180 apic_ap_setup(); 181 182 /* 183 * Save our processor parameters. Note: this information 184 * is needed for clock calibration. 185 */ 186 smp_store_cpu_info(cpuid); 187 188 /* 189 * The topology information must be up to date before 190 * calibrate_delay() and notify_cpu_starting(). 191 */ 192 set_cpu_sibling_map(raw_smp_processor_id()); 193 194 init_freq_invariance(true, false); 195 196 /* 197 * Get our bogomips. 198 * Update loops_per_jiffy in cpu_data. Previous call to 199 * smp_store_cpu_info() stored a value that is close but not as 200 * accurate as the value just calculated. 201 */ 202 calibrate_delay(); 203 cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy; 204 pr_debug("Stack at about %p\n", &cpuid); 205 206 wmb(); 207 208 notify_cpu_starting(cpuid); 209 210 /* 211 * Allow the master to continue. 212 */ 213 cpumask_set_cpu(cpuid, cpu_callin_mask); 214 } 215 216 static int cpu0_logical_apicid; 217 static int enable_start_cpu0; 218 /* 219 * Activate a secondary processor. 220 */ 221 static void notrace start_secondary(void *unused) 222 { 223 /* 224 * Don't put *anything* except direct CPU state initialization 225 * before cpu_init(), SMP booting is too fragile that we want to 226 * limit the things done here to the most necessary things. 227 */ 228 cr4_init(); 229 230 #ifdef CONFIG_X86_32 231 /* switch away from the initial page table */ 232 load_cr3(swapper_pg_dir); 233 __flush_tlb_all(); 234 #endif 235 cpu_init_exception_handling(); 236 cpu_init(); 237 rcu_cpu_starting(raw_smp_processor_id()); 238 x86_cpuinit.early_percpu_clock_init(); 239 preempt_disable(); 240 smp_callin(); 241 242 enable_start_cpu0 = 0; 243 244 /* otherwise gcc will move up smp_processor_id before the cpu_init */ 245 barrier(); 246 /* 247 * Check TSC synchronization with the boot CPU: 248 */ 249 check_tsc_sync_target(); 250 251 speculative_store_bypass_ht_init(); 252 253 /* 254 * Lock vector_lock, set CPU online and bring the vector 255 * allocator online. Online must be set with vector_lock held 256 * to prevent a concurrent irq setup/teardown from seeing a 257 * half valid vector space. 258 */ 259 lock_vector_lock(); 260 set_cpu_online(smp_processor_id(), true); 261 lapic_online(); 262 unlock_vector_lock(); 263 cpu_set_state_online(smp_processor_id()); 264 x86_platform.nmi_init(); 265 266 /* enable local interrupts */ 267 local_irq_enable(); 268 269 x86_cpuinit.setup_percpu_clockev(); 270 271 wmb(); 272 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); 273 } 274 275 /** 276 * topology_is_primary_thread - Check whether CPU is the primary SMT thread 277 * @cpu: CPU to check 278 */ 279 bool topology_is_primary_thread(unsigned int cpu) 280 { 281 return apic_id_is_primary_thread(per_cpu(x86_cpu_to_apicid, cpu)); 282 } 283 284 /** 285 * topology_smt_supported - Check whether SMT is supported by the CPUs 286 */ 287 bool topology_smt_supported(void) 288 { 289 return smp_num_siblings > 1; 290 } 291 292 /** 293 * topology_phys_to_logical_pkg - Map a physical package id to a logical 294 * 295 * Returns logical package id or -1 if not found 296 */ 297 int topology_phys_to_logical_pkg(unsigned int phys_pkg) 298 { 299 int cpu; 300 301 for_each_possible_cpu(cpu) { 302 struct cpuinfo_x86 *c = &cpu_data(cpu); 303 304 if (c->initialized && c->phys_proc_id == phys_pkg) 305 return c->logical_proc_id; 306 } 307 return -1; 308 } 309 EXPORT_SYMBOL(topology_phys_to_logical_pkg); 310 /** 311 * topology_phys_to_logical_die - Map a physical die id to logical 312 * 313 * Returns logical die id or -1 if not found 314 */ 315 int topology_phys_to_logical_die(unsigned int die_id, unsigned int cur_cpu) 316 { 317 int cpu; 318 int proc_id = cpu_data(cur_cpu).phys_proc_id; 319 320 for_each_possible_cpu(cpu) { 321 struct cpuinfo_x86 *c = &cpu_data(cpu); 322 323 if (c->initialized && c->cpu_die_id == die_id && 324 c->phys_proc_id == proc_id) 325 return c->logical_die_id; 326 } 327 return -1; 328 } 329 EXPORT_SYMBOL(topology_phys_to_logical_die); 330 331 /** 332 * topology_update_package_map - Update the physical to logical package map 333 * @pkg: The physical package id as retrieved via CPUID 334 * @cpu: The cpu for which this is updated 335 */ 336 int topology_update_package_map(unsigned int pkg, unsigned int cpu) 337 { 338 int new; 339 340 /* Already available somewhere? */ 341 new = topology_phys_to_logical_pkg(pkg); 342 if (new >= 0) 343 goto found; 344 345 new = logical_packages++; 346 if (new != pkg) { 347 pr_info("CPU %u Converting physical %u to logical package %u\n", 348 cpu, pkg, new); 349 } 350 found: 351 cpu_data(cpu).logical_proc_id = new; 352 return 0; 353 } 354 /** 355 * topology_update_die_map - Update the physical to logical die map 356 * @die: The die id as retrieved via CPUID 357 * @cpu: The cpu for which this is updated 358 */ 359 int topology_update_die_map(unsigned int die, unsigned int cpu) 360 { 361 int new; 362 363 /* Already available somewhere? */ 364 new = topology_phys_to_logical_die(die, cpu); 365 if (new >= 0) 366 goto found; 367 368 new = logical_die++; 369 if (new != die) { 370 pr_info("CPU %u Converting physical %u to logical die %u\n", 371 cpu, die, new); 372 } 373 found: 374 cpu_data(cpu).logical_die_id = new; 375 return 0; 376 } 377 378 void __init smp_store_boot_cpu_info(void) 379 { 380 int id = 0; /* CPU 0 */ 381 struct cpuinfo_x86 *c = &cpu_data(id); 382 383 *c = boot_cpu_data; 384 c->cpu_index = id; 385 topology_update_package_map(c->phys_proc_id, id); 386 topology_update_die_map(c->cpu_die_id, id); 387 c->initialized = true; 388 } 389 390 /* 391 * The bootstrap kernel entry code has set these up. Save them for 392 * a given CPU 393 */ 394 void smp_store_cpu_info(int id) 395 { 396 struct cpuinfo_x86 *c = &cpu_data(id); 397 398 /* Copy boot_cpu_data only on the first bringup */ 399 if (!c->initialized) 400 *c = boot_cpu_data; 401 c->cpu_index = id; 402 /* 403 * During boot time, CPU0 has this setup already. Save the info when 404 * bringing up AP or offlined CPU0. 405 */ 406 identify_secondary_cpu(c); 407 c->initialized = true; 408 } 409 410 static bool 411 topology_same_node(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) 412 { 413 int cpu1 = c->cpu_index, cpu2 = o->cpu_index; 414 415 return (cpu_to_node(cpu1) == cpu_to_node(cpu2)); 416 } 417 418 static bool 419 topology_sane(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o, const char *name) 420 { 421 int cpu1 = c->cpu_index, cpu2 = o->cpu_index; 422 423 return !WARN_ONCE(!topology_same_node(c, o), 424 "sched: CPU #%d's %s-sibling CPU #%d is not on the same node! " 425 "[node: %d != %d]. Ignoring dependency.\n", 426 cpu1, name, cpu2, cpu_to_node(cpu1), cpu_to_node(cpu2)); 427 } 428 429 #define link_mask(mfunc, c1, c2) \ 430 do { \ 431 cpumask_set_cpu((c1), mfunc(c2)); \ 432 cpumask_set_cpu((c2), mfunc(c1)); \ 433 } while (0) 434 435 static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) 436 { 437 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) { 438 int cpu1 = c->cpu_index, cpu2 = o->cpu_index; 439 440 if (c->phys_proc_id == o->phys_proc_id && 441 c->cpu_die_id == o->cpu_die_id && 442 per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) { 443 if (c->cpu_core_id == o->cpu_core_id) 444 return topology_sane(c, o, "smt"); 445 446 if ((c->cu_id != 0xff) && 447 (o->cu_id != 0xff) && 448 (c->cu_id == o->cu_id)) 449 return topology_sane(c, o, "smt"); 450 } 451 452 } else if (c->phys_proc_id == o->phys_proc_id && 453 c->cpu_die_id == o->cpu_die_id && 454 c->cpu_core_id == o->cpu_core_id) { 455 return topology_sane(c, o, "smt"); 456 } 457 458 return false; 459 } 460 461 /* 462 * Define snc_cpu[] for SNC (Sub-NUMA Cluster) CPUs. 463 * 464 * These are Intel CPUs that enumerate an LLC that is shared by 465 * multiple NUMA nodes. The LLC on these systems is shared for 466 * off-package data access but private to the NUMA node (half 467 * of the package) for on-package access. 468 * 469 * CPUID (the source of the information about the LLC) can only 470 * enumerate the cache as being shared *or* unshared, but not 471 * this particular configuration. The CPU in this case enumerates 472 * the cache to be shared across the entire package (spanning both 473 * NUMA nodes). 474 */ 475 476 static const struct x86_cpu_id snc_cpu[] = { 477 X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_X, NULL), 478 {} 479 }; 480 481 static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) 482 { 483 int cpu1 = c->cpu_index, cpu2 = o->cpu_index; 484 485 /* Do not match if we do not have a valid APICID for cpu: */ 486 if (per_cpu(cpu_llc_id, cpu1) == BAD_APICID) 487 return false; 488 489 /* Do not match if LLC id does not match: */ 490 if (per_cpu(cpu_llc_id, cpu1) != per_cpu(cpu_llc_id, cpu2)) 491 return false; 492 493 /* 494 * Allow the SNC topology without warning. Return of false 495 * means 'c' does not share the LLC of 'o'. This will be 496 * reflected to userspace. 497 */ 498 if (!topology_same_node(c, o) && x86_match_cpu(snc_cpu)) 499 return false; 500 501 return topology_sane(c, o, "llc"); 502 } 503 504 /* 505 * Unlike the other levels, we do not enforce keeping a 506 * multicore group inside a NUMA node. If this happens, we will 507 * discard the MC level of the topology later. 508 */ 509 static bool match_pkg(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) 510 { 511 if (c->phys_proc_id == o->phys_proc_id) 512 return true; 513 return false; 514 } 515 516 static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) 517 { 518 if ((c->phys_proc_id == o->phys_proc_id) && 519 (c->cpu_die_id == o->cpu_die_id)) 520 return true; 521 return false; 522 } 523 524 525 #if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC) 526 static inline int x86_sched_itmt_flags(void) 527 { 528 return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0; 529 } 530 531 #ifdef CONFIG_SCHED_MC 532 static int x86_core_flags(void) 533 { 534 return cpu_core_flags() | x86_sched_itmt_flags(); 535 } 536 #endif 537 #ifdef CONFIG_SCHED_SMT 538 static int x86_smt_flags(void) 539 { 540 return cpu_smt_flags() | x86_sched_itmt_flags(); 541 } 542 #endif 543 #endif 544 545 static struct sched_domain_topology_level x86_numa_in_package_topology[] = { 546 #ifdef CONFIG_SCHED_SMT 547 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) }, 548 #endif 549 #ifdef CONFIG_SCHED_MC 550 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) }, 551 #endif 552 { NULL, }, 553 }; 554 555 static struct sched_domain_topology_level x86_topology[] = { 556 #ifdef CONFIG_SCHED_SMT 557 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) }, 558 #endif 559 #ifdef CONFIG_SCHED_MC 560 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) }, 561 #endif 562 { cpu_cpu_mask, SD_INIT_NAME(DIE) }, 563 { NULL, }, 564 }; 565 566 /* 567 * Set if a package/die has multiple NUMA nodes inside. 568 * AMD Magny-Cours, Intel Cluster-on-Die, and Intel 569 * Sub-NUMA Clustering have this. 570 */ 571 static bool x86_has_numa_in_package; 572 573 void set_cpu_sibling_map(int cpu) 574 { 575 bool has_smt = smp_num_siblings > 1; 576 bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1; 577 struct cpuinfo_x86 *c = &cpu_data(cpu); 578 struct cpuinfo_x86 *o; 579 int i, threads; 580 581 cpumask_set_cpu(cpu, cpu_sibling_setup_mask); 582 583 if (!has_mp) { 584 cpumask_set_cpu(cpu, topology_sibling_cpumask(cpu)); 585 cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu)); 586 cpumask_set_cpu(cpu, topology_core_cpumask(cpu)); 587 cpumask_set_cpu(cpu, topology_die_cpumask(cpu)); 588 c->booted_cores = 1; 589 return; 590 } 591 592 for_each_cpu(i, cpu_sibling_setup_mask) { 593 o = &cpu_data(i); 594 595 if ((i == cpu) || (has_smt && match_smt(c, o))) 596 link_mask(topology_sibling_cpumask, cpu, i); 597 598 if ((i == cpu) || (has_mp && match_llc(c, o))) 599 link_mask(cpu_llc_shared_mask, cpu, i); 600 601 } 602 603 /* 604 * This needs a separate iteration over the cpus because we rely on all 605 * topology_sibling_cpumask links to be set-up. 606 */ 607 for_each_cpu(i, cpu_sibling_setup_mask) { 608 o = &cpu_data(i); 609 610 if ((i == cpu) || (has_mp && match_pkg(c, o))) { 611 link_mask(topology_core_cpumask, cpu, i); 612 613 /* 614 * Does this new cpu bringup a new core? 615 */ 616 if (cpumask_weight( 617 topology_sibling_cpumask(cpu)) == 1) { 618 /* 619 * for each core in package, increment 620 * the booted_cores for this new cpu 621 */ 622 if (cpumask_first( 623 topology_sibling_cpumask(i)) == i) 624 c->booted_cores++; 625 /* 626 * increment the core count for all 627 * the other cpus in this package 628 */ 629 if (i != cpu) 630 cpu_data(i).booted_cores++; 631 } else if (i != cpu && !c->booted_cores) 632 c->booted_cores = cpu_data(i).booted_cores; 633 } 634 if (match_pkg(c, o) && !topology_same_node(c, o)) 635 x86_has_numa_in_package = true; 636 637 if ((i == cpu) || (has_mp && match_die(c, o))) 638 link_mask(topology_die_cpumask, cpu, i); 639 } 640 641 threads = cpumask_weight(topology_sibling_cpumask(cpu)); 642 if (threads > __max_smt_threads) 643 __max_smt_threads = threads; 644 } 645 646 /* maps the cpu to the sched domain representing multi-core */ 647 const struct cpumask *cpu_coregroup_mask(int cpu) 648 { 649 return cpu_llc_shared_mask(cpu); 650 } 651 652 static void impress_friends(void) 653 { 654 int cpu; 655 unsigned long bogosum = 0; 656 /* 657 * Allow the user to impress friends. 658 */ 659 pr_debug("Before bogomips\n"); 660 for_each_possible_cpu(cpu) 661 if (cpumask_test_cpu(cpu, cpu_callout_mask)) 662 bogosum += cpu_data(cpu).loops_per_jiffy; 663 pr_info("Total of %d processors activated (%lu.%02lu BogoMIPS)\n", 664 num_online_cpus(), 665 bogosum/(500000/HZ), 666 (bogosum/(5000/HZ))%100); 667 668 pr_debug("Before bogocount - setting activated=1\n"); 669 } 670 671 void __inquire_remote_apic(int apicid) 672 { 673 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 }; 674 const char * const names[] = { "ID", "VERSION", "SPIV" }; 675 int timeout; 676 u32 status; 677 678 pr_info("Inquiring remote APIC 0x%x...\n", apicid); 679 680 for (i = 0; i < ARRAY_SIZE(regs); i++) { 681 pr_info("... APIC 0x%x %s: ", apicid, names[i]); 682 683 /* 684 * Wait for idle. 685 */ 686 status = safe_apic_wait_icr_idle(); 687 if (status) 688 pr_cont("a previous APIC delivery may have failed\n"); 689 690 apic_icr_write(APIC_DM_REMRD | regs[i], apicid); 691 692 timeout = 0; 693 do { 694 udelay(100); 695 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK; 696 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000); 697 698 switch (status) { 699 case APIC_ICR_RR_VALID: 700 status = apic_read(APIC_RRR); 701 pr_cont("%08x\n", status); 702 break; 703 default: 704 pr_cont("failed\n"); 705 } 706 } 707 } 708 709 /* 710 * The Multiprocessor Specification 1.4 (1997) example code suggests 711 * that there should be a 10ms delay between the BSP asserting INIT 712 * and de-asserting INIT, when starting a remote processor. 713 * But that slows boot and resume on modern processors, which include 714 * many cores and don't require that delay. 715 * 716 * Cmdline "init_cpu_udelay=" is available to over-ride this delay. 717 * Modern processor families are quirked to remove the delay entirely. 718 */ 719 #define UDELAY_10MS_DEFAULT 10000 720 721 static unsigned int init_udelay = UINT_MAX; 722 723 static int __init cpu_init_udelay(char *str) 724 { 725 get_option(&str, &init_udelay); 726 727 return 0; 728 } 729 early_param("cpu_init_udelay", cpu_init_udelay); 730 731 static void __init smp_quirk_init_udelay(void) 732 { 733 /* if cmdline changed it from default, leave it alone */ 734 if (init_udelay != UINT_MAX) 735 return; 736 737 /* if modern processor, use no delay */ 738 if (((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 6)) || 739 ((boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) && (boot_cpu_data.x86 >= 0x18)) || 740 ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && (boot_cpu_data.x86 >= 0xF))) { 741 init_udelay = 0; 742 return; 743 } 744 /* else, use legacy delay */ 745 init_udelay = UDELAY_10MS_DEFAULT; 746 } 747 748 /* 749 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal 750 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this 751 * won't ... remember to clear down the APIC, etc later. 752 */ 753 int 754 wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip) 755 { 756 u32 dm = apic->dest_mode_logical ? APIC_DEST_LOGICAL : APIC_DEST_PHYSICAL; 757 unsigned long send_status, accept_status = 0; 758 int maxlvt; 759 760 /* Target chip */ 761 /* Boot on the stack */ 762 /* Kick the second */ 763 apic_icr_write(APIC_DM_NMI | dm, apicid); 764 765 pr_debug("Waiting for send to finish...\n"); 766 send_status = safe_apic_wait_icr_idle(); 767 768 /* 769 * Give the other CPU some time to accept the IPI. 770 */ 771 udelay(200); 772 if (APIC_INTEGRATED(boot_cpu_apic_version)) { 773 maxlvt = lapic_get_maxlvt(); 774 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ 775 apic_write(APIC_ESR, 0); 776 accept_status = (apic_read(APIC_ESR) & 0xEF); 777 } 778 pr_debug("NMI sent\n"); 779 780 if (send_status) 781 pr_err("APIC never delivered???\n"); 782 if (accept_status) 783 pr_err("APIC delivery error (%lx)\n", accept_status); 784 785 return (send_status | accept_status); 786 } 787 788 static int 789 wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip) 790 { 791 unsigned long send_status = 0, accept_status = 0; 792 int maxlvt, num_starts, j; 793 794 maxlvt = lapic_get_maxlvt(); 795 796 /* 797 * Be paranoid about clearing APIC errors. 798 */ 799 if (APIC_INTEGRATED(boot_cpu_apic_version)) { 800 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ 801 apic_write(APIC_ESR, 0); 802 apic_read(APIC_ESR); 803 } 804 805 pr_debug("Asserting INIT\n"); 806 807 /* 808 * Turn INIT on target chip 809 */ 810 /* 811 * Send IPI 812 */ 813 apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT, 814 phys_apicid); 815 816 pr_debug("Waiting for send to finish...\n"); 817 send_status = safe_apic_wait_icr_idle(); 818 819 udelay(init_udelay); 820 821 pr_debug("Deasserting INIT\n"); 822 823 /* Target chip */ 824 /* Send IPI */ 825 apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid); 826 827 pr_debug("Waiting for send to finish...\n"); 828 send_status = safe_apic_wait_icr_idle(); 829 830 mb(); 831 832 /* 833 * Should we send STARTUP IPIs ? 834 * 835 * Determine this based on the APIC version. 836 * If we don't have an integrated APIC, don't send the STARTUP IPIs. 837 */ 838 if (APIC_INTEGRATED(boot_cpu_apic_version)) 839 num_starts = 2; 840 else 841 num_starts = 0; 842 843 /* 844 * Run STARTUP IPI loop. 845 */ 846 pr_debug("#startup loops: %d\n", num_starts); 847 848 for (j = 1; j <= num_starts; j++) { 849 pr_debug("Sending STARTUP #%d\n", j); 850 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ 851 apic_write(APIC_ESR, 0); 852 apic_read(APIC_ESR); 853 pr_debug("After apic_write\n"); 854 855 /* 856 * STARTUP IPI 857 */ 858 859 /* Target chip */ 860 /* Boot on the stack */ 861 /* Kick the second */ 862 apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12), 863 phys_apicid); 864 865 /* 866 * Give the other CPU some time to accept the IPI. 867 */ 868 if (init_udelay == 0) 869 udelay(10); 870 else 871 udelay(300); 872 873 pr_debug("Startup point 1\n"); 874 875 pr_debug("Waiting for send to finish...\n"); 876 send_status = safe_apic_wait_icr_idle(); 877 878 /* 879 * Give the other CPU some time to accept the IPI. 880 */ 881 if (init_udelay == 0) 882 udelay(10); 883 else 884 udelay(200); 885 886 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ 887 apic_write(APIC_ESR, 0); 888 accept_status = (apic_read(APIC_ESR) & 0xEF); 889 if (send_status || accept_status) 890 break; 891 } 892 pr_debug("After Startup\n"); 893 894 if (send_status) 895 pr_err("APIC never delivered???\n"); 896 if (accept_status) 897 pr_err("APIC delivery error (%lx)\n", accept_status); 898 899 return (send_status | accept_status); 900 } 901 902 /* reduce the number of lines printed when booting a large cpu count system */ 903 static void announce_cpu(int cpu, int apicid) 904 { 905 static int current_node = NUMA_NO_NODE; 906 int node = early_cpu_to_node(cpu); 907 static int width, node_width; 908 909 if (!width) 910 width = num_digits(num_possible_cpus()) + 1; /* + '#' sign */ 911 912 if (!node_width) 913 node_width = num_digits(num_possible_nodes()) + 1; /* + '#' */ 914 915 if (cpu == 1) 916 printk(KERN_INFO "x86: Booting SMP configuration:\n"); 917 918 if (system_state < SYSTEM_RUNNING) { 919 if (node != current_node) { 920 if (current_node > (-1)) 921 pr_cont("\n"); 922 current_node = node; 923 924 printk(KERN_INFO ".... node %*s#%d, CPUs: ", 925 node_width - num_digits(node), " ", node); 926 } 927 928 /* Add padding for the BSP */ 929 if (cpu == 1) 930 pr_cont("%*s", width + 1, " "); 931 932 pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu); 933 934 } else 935 pr_info("Booting Node %d Processor %d APIC 0x%x\n", 936 node, cpu, apicid); 937 } 938 939 static int wakeup_cpu0_nmi(unsigned int cmd, struct pt_regs *regs) 940 { 941 int cpu; 942 943 cpu = smp_processor_id(); 944 if (cpu == 0 && !cpu_online(cpu) && enable_start_cpu0) 945 return NMI_HANDLED; 946 947 return NMI_DONE; 948 } 949 950 /* 951 * Wake up AP by INIT, INIT, STARTUP sequence. 952 * 953 * Instead of waiting for STARTUP after INITs, BSP will execute the BIOS 954 * boot-strap code which is not a desired behavior for waking up BSP. To 955 * void the boot-strap code, wake up CPU0 by NMI instead. 956 * 957 * This works to wake up soft offlined CPU0 only. If CPU0 is hard offlined 958 * (i.e. physically hot removed and then hot added), NMI won't wake it up. 959 * We'll change this code in the future to wake up hard offlined CPU0 if 960 * real platform and request are available. 961 */ 962 static int 963 wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip, int apicid, 964 int *cpu0_nmi_registered) 965 { 966 int id; 967 int boot_error; 968 969 preempt_disable(); 970 971 /* 972 * Wake up AP by INIT, INIT, STARTUP sequence. 973 */ 974 if (cpu) { 975 boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip); 976 goto out; 977 } 978 979 /* 980 * Wake up BSP by nmi. 981 * 982 * Register a NMI handler to help wake up CPU0. 983 */ 984 boot_error = register_nmi_handler(NMI_LOCAL, 985 wakeup_cpu0_nmi, 0, "wake_cpu0"); 986 987 if (!boot_error) { 988 enable_start_cpu0 = 1; 989 *cpu0_nmi_registered = 1; 990 id = apic->dest_mode_logical ? cpu0_logical_apicid : apicid; 991 boot_error = wakeup_secondary_cpu_via_nmi(id, start_ip); 992 } 993 994 out: 995 preempt_enable(); 996 997 return boot_error; 998 } 999 1000 int common_cpu_up(unsigned int cpu, struct task_struct *idle) 1001 { 1002 int ret; 1003 1004 /* Just in case we booted with a single CPU. */ 1005 alternatives_enable_smp(); 1006 1007 per_cpu(current_task, cpu) = idle; 1008 cpu_init_stack_canary(cpu, idle); 1009 1010 /* Initialize the interrupt stack(s) */ 1011 ret = irq_init_percpu_irqstack(cpu); 1012 if (ret) 1013 return ret; 1014 1015 #ifdef CONFIG_X86_32 1016 /* Stack for startup_32 can be just as for start_secondary onwards */ 1017 per_cpu(cpu_current_top_of_stack, cpu) = task_top_of_stack(idle); 1018 #else 1019 initial_gs = per_cpu_offset(cpu); 1020 #endif 1021 return 0; 1022 } 1023 1024 /* 1025 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad 1026 * (ie clustered apic addressing mode), this is a LOGICAL apic ID. 1027 * Returns zero if CPU booted OK, else error code from 1028 * ->wakeup_secondary_cpu. 1029 */ 1030 static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle, 1031 int *cpu0_nmi_registered) 1032 { 1033 /* start_ip had better be page-aligned! */ 1034 unsigned long start_ip = real_mode_header->trampoline_start; 1035 1036 unsigned long boot_error = 0; 1037 unsigned long timeout; 1038 1039 idle->thread.sp = (unsigned long)task_pt_regs(idle); 1040 early_gdt_descr.address = (unsigned long)get_cpu_gdt_rw(cpu); 1041 initial_code = (unsigned long)start_secondary; 1042 initial_stack = idle->thread.sp; 1043 1044 /* Enable the espfix hack for this CPU */ 1045 init_espfix_ap(cpu); 1046 1047 /* So we see what's up */ 1048 announce_cpu(cpu, apicid); 1049 1050 /* 1051 * This grunge runs the startup process for 1052 * the targeted processor. 1053 */ 1054 1055 if (x86_platform.legacy.warm_reset) { 1056 1057 pr_debug("Setting warm reset code and vector.\n"); 1058 1059 smpboot_setup_warm_reset_vector(start_ip); 1060 /* 1061 * Be paranoid about clearing APIC errors. 1062 */ 1063 if (APIC_INTEGRATED(boot_cpu_apic_version)) { 1064 apic_write(APIC_ESR, 0); 1065 apic_read(APIC_ESR); 1066 } 1067 } 1068 1069 /* 1070 * AP might wait on cpu_callout_mask in cpu_init() with 1071 * cpu_initialized_mask set if previous attempt to online 1072 * it timed-out. Clear cpu_initialized_mask so that after 1073 * INIT/SIPI it could start with a clean state. 1074 */ 1075 cpumask_clear_cpu(cpu, cpu_initialized_mask); 1076 smp_mb(); 1077 1078 /* 1079 * Wake up a CPU in difference cases: 1080 * - Use the method in the APIC driver if it's defined 1081 * Otherwise, 1082 * - Use an INIT boot APIC message for APs or NMI for BSP. 1083 */ 1084 if (apic->wakeup_secondary_cpu) 1085 boot_error = apic->wakeup_secondary_cpu(apicid, start_ip); 1086 else 1087 boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid, 1088 cpu0_nmi_registered); 1089 1090 if (!boot_error) { 1091 /* 1092 * Wait 10s total for first sign of life from AP 1093 */ 1094 boot_error = -1; 1095 timeout = jiffies + 10*HZ; 1096 while (time_before(jiffies, timeout)) { 1097 if (cpumask_test_cpu(cpu, cpu_initialized_mask)) { 1098 /* 1099 * Tell AP to proceed with initialization 1100 */ 1101 cpumask_set_cpu(cpu, cpu_callout_mask); 1102 boot_error = 0; 1103 break; 1104 } 1105 schedule(); 1106 } 1107 } 1108 1109 if (!boot_error) { 1110 /* 1111 * Wait till AP completes initial initialization 1112 */ 1113 while (!cpumask_test_cpu(cpu, cpu_callin_mask)) { 1114 /* 1115 * Allow other tasks to run while we wait for the 1116 * AP to come online. This also gives a chance 1117 * for the MTRR work(triggered by the AP coming online) 1118 * to be completed in the stop machine context. 1119 */ 1120 schedule(); 1121 } 1122 } 1123 1124 if (x86_platform.legacy.warm_reset) { 1125 /* 1126 * Cleanup possible dangling ends... 1127 */ 1128 smpboot_restore_warm_reset_vector(); 1129 } 1130 1131 return boot_error; 1132 } 1133 1134 int native_cpu_up(unsigned int cpu, struct task_struct *tidle) 1135 { 1136 int apicid = apic->cpu_present_to_apicid(cpu); 1137 int cpu0_nmi_registered = 0; 1138 unsigned long flags; 1139 int err, ret = 0; 1140 1141 lockdep_assert_irqs_enabled(); 1142 1143 pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu); 1144 1145 if (apicid == BAD_APICID || 1146 !physid_isset(apicid, phys_cpu_present_map) || 1147 !apic->apic_id_valid(apicid)) { 1148 pr_err("%s: bad cpu %d\n", __func__, cpu); 1149 return -EINVAL; 1150 } 1151 1152 /* 1153 * Already booted CPU? 1154 */ 1155 if (cpumask_test_cpu(cpu, cpu_callin_mask)) { 1156 pr_debug("do_boot_cpu %d Already started\n", cpu); 1157 return -ENOSYS; 1158 } 1159 1160 /* 1161 * Save current MTRR state in case it was changed since early boot 1162 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync: 1163 */ 1164 mtrr_save_state(); 1165 1166 /* x86 CPUs take themselves offline, so delayed offline is OK. */ 1167 err = cpu_check_up_prepare(cpu); 1168 if (err && err != -EBUSY) 1169 return err; 1170 1171 /* the FPU context is blank, nobody can own it */ 1172 per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL; 1173 1174 err = common_cpu_up(cpu, tidle); 1175 if (err) 1176 return err; 1177 1178 err = do_boot_cpu(apicid, cpu, tidle, &cpu0_nmi_registered); 1179 if (err) { 1180 pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu); 1181 ret = -EIO; 1182 goto unreg_nmi; 1183 } 1184 1185 /* 1186 * Check TSC synchronization with the AP (keep irqs disabled 1187 * while doing so): 1188 */ 1189 local_irq_save(flags); 1190 check_tsc_sync_source(cpu); 1191 local_irq_restore(flags); 1192 1193 while (!cpu_online(cpu)) { 1194 cpu_relax(); 1195 touch_nmi_watchdog(); 1196 } 1197 1198 unreg_nmi: 1199 /* 1200 * Clean up the nmi handler. Do this after the callin and callout sync 1201 * to avoid impact of possible long unregister time. 1202 */ 1203 if (cpu0_nmi_registered) 1204 unregister_nmi_handler(NMI_LOCAL, "wake_cpu0"); 1205 1206 return ret; 1207 } 1208 1209 /** 1210 * arch_disable_smp_support() - disables SMP support for x86 at runtime 1211 */ 1212 void arch_disable_smp_support(void) 1213 { 1214 disable_ioapic_support(); 1215 } 1216 1217 /* 1218 * Fall back to non SMP mode after errors. 1219 * 1220 * RED-PEN audit/test this more. I bet there is more state messed up here. 1221 */ 1222 static __init void disable_smp(void) 1223 { 1224 pr_info("SMP disabled\n"); 1225 1226 disable_ioapic_support(); 1227 1228 init_cpu_present(cpumask_of(0)); 1229 init_cpu_possible(cpumask_of(0)); 1230 1231 if (smp_found_config) 1232 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map); 1233 else 1234 physid_set_mask_of_physid(0, &phys_cpu_present_map); 1235 cpumask_set_cpu(0, topology_sibling_cpumask(0)); 1236 cpumask_set_cpu(0, topology_core_cpumask(0)); 1237 cpumask_set_cpu(0, topology_die_cpumask(0)); 1238 } 1239 1240 /* 1241 * Various sanity checks. 1242 */ 1243 static void __init smp_sanity_check(void) 1244 { 1245 preempt_disable(); 1246 1247 #if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32) 1248 if (def_to_bigsmp && nr_cpu_ids > 8) { 1249 unsigned int cpu; 1250 unsigned nr; 1251 1252 pr_warn("More than 8 CPUs detected - skipping them\n" 1253 "Use CONFIG_X86_BIGSMP\n"); 1254 1255 nr = 0; 1256 for_each_present_cpu(cpu) { 1257 if (nr >= 8) 1258 set_cpu_present(cpu, false); 1259 nr++; 1260 } 1261 1262 nr = 0; 1263 for_each_possible_cpu(cpu) { 1264 if (nr >= 8) 1265 set_cpu_possible(cpu, false); 1266 nr++; 1267 } 1268 1269 nr_cpu_ids = 8; 1270 } 1271 #endif 1272 1273 if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) { 1274 pr_warn("weird, boot CPU (#%d) not listed by the BIOS\n", 1275 hard_smp_processor_id()); 1276 1277 physid_set(hard_smp_processor_id(), phys_cpu_present_map); 1278 } 1279 1280 /* 1281 * Should not be necessary because the MP table should list the boot 1282 * CPU too, but we do it for the sake of robustness anyway. 1283 */ 1284 if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) { 1285 pr_notice("weird, boot CPU (#%d) not listed by the BIOS\n", 1286 boot_cpu_physical_apicid); 1287 physid_set(hard_smp_processor_id(), phys_cpu_present_map); 1288 } 1289 preempt_enable(); 1290 } 1291 1292 static void __init smp_cpu_index_default(void) 1293 { 1294 int i; 1295 struct cpuinfo_x86 *c; 1296 1297 for_each_possible_cpu(i) { 1298 c = &cpu_data(i); 1299 /* mark all to hotplug */ 1300 c->cpu_index = nr_cpu_ids; 1301 } 1302 } 1303 1304 static void __init smp_get_logical_apicid(void) 1305 { 1306 if (x2apic_mode) 1307 cpu0_logical_apicid = apic_read(APIC_LDR); 1308 else 1309 cpu0_logical_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR)); 1310 } 1311 1312 /* 1313 * Prepare for SMP bootup. 1314 * @max_cpus: configured maximum number of CPUs, It is a legacy parameter 1315 * for common interface support. 1316 */ 1317 void __init native_smp_prepare_cpus(unsigned int max_cpus) 1318 { 1319 unsigned int i; 1320 1321 smp_cpu_index_default(); 1322 1323 /* 1324 * Setup boot CPU information 1325 */ 1326 smp_store_boot_cpu_info(); /* Final full version of the data */ 1327 cpumask_copy(cpu_callin_mask, cpumask_of(0)); 1328 mb(); 1329 1330 for_each_possible_cpu(i) { 1331 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL); 1332 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL); 1333 zalloc_cpumask_var(&per_cpu(cpu_die_map, i), GFP_KERNEL); 1334 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL); 1335 } 1336 1337 /* 1338 * Set 'default' x86 topology, this matches default_topology() in that 1339 * it has NUMA nodes as a topology level. See also 1340 * native_smp_cpus_done(). 1341 * 1342 * Must be done before set_cpus_sibling_map() is ran. 1343 */ 1344 set_sched_topology(x86_topology); 1345 1346 set_cpu_sibling_map(0); 1347 init_freq_invariance(false, false); 1348 smp_sanity_check(); 1349 1350 switch (apic_intr_mode) { 1351 case APIC_PIC: 1352 case APIC_VIRTUAL_WIRE_NO_CONFIG: 1353 disable_smp(); 1354 return; 1355 case APIC_SYMMETRIC_IO_NO_ROUTING: 1356 disable_smp(); 1357 /* Setup local timer */ 1358 x86_init.timers.setup_percpu_clockev(); 1359 return; 1360 case APIC_VIRTUAL_WIRE: 1361 case APIC_SYMMETRIC_IO: 1362 break; 1363 } 1364 1365 /* Setup local timer */ 1366 x86_init.timers.setup_percpu_clockev(); 1367 1368 smp_get_logical_apicid(); 1369 1370 pr_info("CPU0: "); 1371 print_cpu_info(&cpu_data(0)); 1372 1373 uv_system_init(); 1374 1375 set_mtrr_aps_delayed_init(); 1376 1377 smp_quirk_init_udelay(); 1378 1379 speculative_store_bypass_ht_init(); 1380 } 1381 1382 void arch_thaw_secondary_cpus_begin(void) 1383 { 1384 set_mtrr_aps_delayed_init(); 1385 } 1386 1387 void arch_thaw_secondary_cpus_end(void) 1388 { 1389 mtrr_aps_init(); 1390 } 1391 1392 /* 1393 * Early setup to make printk work. 1394 */ 1395 void __init native_smp_prepare_boot_cpu(void) 1396 { 1397 int me = smp_processor_id(); 1398 switch_to_new_gdt(me); 1399 /* already set me in cpu_online_mask in boot_cpu_init() */ 1400 cpumask_set_cpu(me, cpu_callout_mask); 1401 cpu_set_state_online(me); 1402 native_pv_lock_init(); 1403 } 1404 1405 void __init calculate_max_logical_packages(void) 1406 { 1407 int ncpus; 1408 1409 /* 1410 * Today neither Intel nor AMD support heterogenous systems so 1411 * extrapolate the boot cpu's data to all packages. 1412 */ 1413 ncpus = cpu_data(0).booted_cores * topology_max_smt_threads(); 1414 __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus); 1415 pr_info("Max logical packages: %u\n", __max_logical_packages); 1416 } 1417 1418 void __init native_smp_cpus_done(unsigned int max_cpus) 1419 { 1420 pr_debug("Boot done\n"); 1421 1422 calculate_max_logical_packages(); 1423 1424 if (x86_has_numa_in_package) 1425 set_sched_topology(x86_numa_in_package_topology); 1426 1427 nmi_selftest(); 1428 impress_friends(); 1429 mtrr_aps_init(); 1430 } 1431 1432 static int __initdata setup_possible_cpus = -1; 1433 static int __init _setup_possible_cpus(char *str) 1434 { 1435 get_option(&str, &setup_possible_cpus); 1436 return 0; 1437 } 1438 early_param("possible_cpus", _setup_possible_cpus); 1439 1440 1441 /* 1442 * cpu_possible_mask should be static, it cannot change as cpu's 1443 * are onlined, or offlined. The reason is per-cpu data-structures 1444 * are allocated by some modules at init time, and don't expect to 1445 * do this dynamically on cpu arrival/departure. 1446 * cpu_present_mask on the other hand can change dynamically. 1447 * In case when cpu_hotplug is not compiled, then we resort to current 1448 * behaviour, which is cpu_possible == cpu_present. 1449 * - Ashok Raj 1450 * 1451 * Three ways to find out the number of additional hotplug CPUs: 1452 * - If the BIOS specified disabled CPUs in ACPI/mptables use that. 1453 * - The user can overwrite it with possible_cpus=NUM 1454 * - Otherwise don't reserve additional CPUs. 1455 * We do this because additional CPUs waste a lot of memory. 1456 * -AK 1457 */ 1458 __init void prefill_possible_map(void) 1459 { 1460 int i, possible; 1461 1462 /* No boot processor was found in mptable or ACPI MADT */ 1463 if (!num_processors) { 1464 if (boot_cpu_has(X86_FEATURE_APIC)) { 1465 int apicid = boot_cpu_physical_apicid; 1466 int cpu = hard_smp_processor_id(); 1467 1468 pr_warn("Boot CPU (id %d) not listed by BIOS\n", cpu); 1469 1470 /* Make sure boot cpu is enumerated */ 1471 if (apic->cpu_present_to_apicid(0) == BAD_APICID && 1472 apic->apic_id_valid(apicid)) 1473 generic_processor_info(apicid, boot_cpu_apic_version); 1474 } 1475 1476 if (!num_processors) 1477 num_processors = 1; 1478 } 1479 1480 i = setup_max_cpus ?: 1; 1481 if (setup_possible_cpus == -1) { 1482 possible = num_processors; 1483 #ifdef CONFIG_HOTPLUG_CPU 1484 if (setup_max_cpus) 1485 possible += disabled_cpus; 1486 #else 1487 if (possible > i) 1488 possible = i; 1489 #endif 1490 } else 1491 possible = setup_possible_cpus; 1492 1493 total_cpus = max_t(int, possible, num_processors + disabled_cpus); 1494 1495 /* nr_cpu_ids could be reduced via nr_cpus= */ 1496 if (possible > nr_cpu_ids) { 1497 pr_warn("%d Processors exceeds NR_CPUS limit of %u\n", 1498 possible, nr_cpu_ids); 1499 possible = nr_cpu_ids; 1500 } 1501 1502 #ifdef CONFIG_HOTPLUG_CPU 1503 if (!setup_max_cpus) 1504 #endif 1505 if (possible > i) { 1506 pr_warn("%d Processors exceeds max_cpus limit of %u\n", 1507 possible, setup_max_cpus); 1508 possible = i; 1509 } 1510 1511 nr_cpu_ids = possible; 1512 1513 pr_info("Allowing %d CPUs, %d hotplug CPUs\n", 1514 possible, max_t(int, possible - num_processors, 0)); 1515 1516 reset_cpu_possible_mask(); 1517 1518 for (i = 0; i < possible; i++) 1519 set_cpu_possible(i, true); 1520 } 1521 1522 #ifdef CONFIG_HOTPLUG_CPU 1523 1524 /* Recompute SMT state for all CPUs on offline */ 1525 static void recompute_smt_state(void) 1526 { 1527 int max_threads, cpu; 1528 1529 max_threads = 0; 1530 for_each_online_cpu (cpu) { 1531 int threads = cpumask_weight(topology_sibling_cpumask(cpu)); 1532 1533 if (threads > max_threads) 1534 max_threads = threads; 1535 } 1536 __max_smt_threads = max_threads; 1537 } 1538 1539 static void remove_siblinginfo(int cpu) 1540 { 1541 int sibling; 1542 struct cpuinfo_x86 *c = &cpu_data(cpu); 1543 1544 for_each_cpu(sibling, topology_core_cpumask(cpu)) { 1545 cpumask_clear_cpu(cpu, topology_core_cpumask(sibling)); 1546 /*/ 1547 * last thread sibling in this cpu core going down 1548 */ 1549 if (cpumask_weight(topology_sibling_cpumask(cpu)) == 1) 1550 cpu_data(sibling).booted_cores--; 1551 } 1552 1553 for_each_cpu(sibling, topology_die_cpumask(cpu)) 1554 cpumask_clear_cpu(cpu, topology_die_cpumask(sibling)); 1555 for_each_cpu(sibling, topology_sibling_cpumask(cpu)) 1556 cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling)); 1557 for_each_cpu(sibling, cpu_llc_shared_mask(cpu)) 1558 cpumask_clear_cpu(cpu, cpu_llc_shared_mask(sibling)); 1559 cpumask_clear(cpu_llc_shared_mask(cpu)); 1560 cpumask_clear(topology_sibling_cpumask(cpu)); 1561 cpumask_clear(topology_core_cpumask(cpu)); 1562 cpumask_clear(topology_die_cpumask(cpu)); 1563 c->cpu_core_id = 0; 1564 c->booted_cores = 0; 1565 cpumask_clear_cpu(cpu, cpu_sibling_setup_mask); 1566 recompute_smt_state(); 1567 } 1568 1569 static void remove_cpu_from_maps(int cpu) 1570 { 1571 set_cpu_online(cpu, false); 1572 cpumask_clear_cpu(cpu, cpu_callout_mask); 1573 cpumask_clear_cpu(cpu, cpu_callin_mask); 1574 /* was set by cpu_init() */ 1575 cpumask_clear_cpu(cpu, cpu_initialized_mask); 1576 numa_remove_cpu(cpu); 1577 } 1578 1579 void cpu_disable_common(void) 1580 { 1581 int cpu = smp_processor_id(); 1582 1583 remove_siblinginfo(cpu); 1584 1585 /* It's now safe to remove this processor from the online map */ 1586 lock_vector_lock(); 1587 remove_cpu_from_maps(cpu); 1588 unlock_vector_lock(); 1589 fixup_irqs(); 1590 lapic_offline(); 1591 } 1592 1593 int native_cpu_disable(void) 1594 { 1595 int ret; 1596 1597 ret = lapic_can_unplug_cpu(); 1598 if (ret) 1599 return ret; 1600 1601 cpu_disable_common(); 1602 1603 /* 1604 * Disable the local APIC. Otherwise IPI broadcasts will reach 1605 * it. It still responds normally to INIT, NMI, SMI, and SIPI 1606 * messages. 1607 * 1608 * Disabling the APIC must happen after cpu_disable_common() 1609 * which invokes fixup_irqs(). 1610 * 1611 * Disabling the APIC preserves already set bits in IRR, but 1612 * an interrupt arriving after disabling the local APIC does not 1613 * set the corresponding IRR bit. 1614 * 1615 * fixup_irqs() scans IRR for set bits so it can raise a not 1616 * yet handled interrupt on the new destination CPU via an IPI 1617 * but obviously it can't do so for IRR bits which are not set. 1618 * IOW, interrupts arriving after disabling the local APIC will 1619 * be lost. 1620 */ 1621 apic_soft_disable(); 1622 1623 return 0; 1624 } 1625 1626 int common_cpu_die(unsigned int cpu) 1627 { 1628 int ret = 0; 1629 1630 /* We don't do anything here: idle task is faking death itself. */ 1631 1632 /* They ack this in play_dead() by setting CPU_DEAD */ 1633 if (cpu_wait_death(cpu, 5)) { 1634 if (system_state == SYSTEM_RUNNING) 1635 pr_info("CPU %u is now offline\n", cpu); 1636 } else { 1637 pr_err("CPU %u didn't die...\n", cpu); 1638 ret = -1; 1639 } 1640 1641 return ret; 1642 } 1643 1644 void native_cpu_die(unsigned int cpu) 1645 { 1646 common_cpu_die(cpu); 1647 } 1648 1649 void play_dead_common(void) 1650 { 1651 idle_task_exit(); 1652 1653 /* Ack it */ 1654 (void)cpu_report_death(); 1655 1656 /* 1657 * With physical CPU hotplug, we should halt the cpu 1658 */ 1659 local_irq_disable(); 1660 } 1661 1662 bool wakeup_cpu0(void) 1663 { 1664 if (smp_processor_id() == 0 && enable_start_cpu0) 1665 return true; 1666 1667 return false; 1668 } 1669 1670 /* 1671 * We need to flush the caches before going to sleep, lest we have 1672 * dirty data in our caches when we come back up. 1673 */ 1674 static inline void mwait_play_dead(void) 1675 { 1676 unsigned int eax, ebx, ecx, edx; 1677 unsigned int highest_cstate = 0; 1678 unsigned int highest_subcstate = 0; 1679 void *mwait_ptr; 1680 int i; 1681 1682 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD || 1683 boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) 1684 return; 1685 if (!this_cpu_has(X86_FEATURE_MWAIT)) 1686 return; 1687 if (!this_cpu_has(X86_FEATURE_CLFLUSH)) 1688 return; 1689 if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF) 1690 return; 1691 1692 eax = CPUID_MWAIT_LEAF; 1693 ecx = 0; 1694 native_cpuid(&eax, &ebx, &ecx, &edx); 1695 1696 /* 1697 * eax will be 0 if EDX enumeration is not valid. 1698 * Initialized below to cstate, sub_cstate value when EDX is valid. 1699 */ 1700 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) { 1701 eax = 0; 1702 } else { 1703 edx >>= MWAIT_SUBSTATE_SIZE; 1704 for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) { 1705 if (edx & MWAIT_SUBSTATE_MASK) { 1706 highest_cstate = i; 1707 highest_subcstate = edx & MWAIT_SUBSTATE_MASK; 1708 } 1709 } 1710 eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) | 1711 (highest_subcstate - 1); 1712 } 1713 1714 /* 1715 * This should be a memory location in a cache line which is 1716 * unlikely to be touched by other processors. The actual 1717 * content is immaterial as it is not actually modified in any way. 1718 */ 1719 mwait_ptr = ¤t_thread_info()->flags; 1720 1721 wbinvd(); 1722 1723 while (1) { 1724 /* 1725 * The CLFLUSH is a workaround for erratum AAI65 for 1726 * the Xeon 7400 series. It's not clear it is actually 1727 * needed, but it should be harmless in either case. 1728 * The WBINVD is insufficient due to the spurious-wakeup 1729 * case where we return around the loop. 1730 */ 1731 mb(); 1732 clflush(mwait_ptr); 1733 mb(); 1734 __monitor(mwait_ptr, 0, 0); 1735 mb(); 1736 __mwait(eax, 0); 1737 /* 1738 * If NMI wants to wake up CPU0, start CPU0. 1739 */ 1740 if (wakeup_cpu0()) 1741 start_cpu0(); 1742 } 1743 } 1744 1745 void hlt_play_dead(void) 1746 { 1747 if (__this_cpu_read(cpu_info.x86) >= 4) 1748 wbinvd(); 1749 1750 while (1) { 1751 native_halt(); 1752 /* 1753 * If NMI wants to wake up CPU0, start CPU0. 1754 */ 1755 if (wakeup_cpu0()) 1756 start_cpu0(); 1757 } 1758 } 1759 1760 void native_play_dead(void) 1761 { 1762 play_dead_common(); 1763 tboot_shutdown(TB_SHUTDOWN_WFS); 1764 1765 mwait_play_dead(); /* Only returns on failure */ 1766 if (cpuidle_play_dead()) 1767 hlt_play_dead(); 1768 } 1769 1770 #else /* ... !CONFIG_HOTPLUG_CPU */ 1771 int native_cpu_disable(void) 1772 { 1773 return -ENOSYS; 1774 } 1775 1776 void native_cpu_die(unsigned int cpu) 1777 { 1778 /* We said "no" in __cpu_disable */ 1779 BUG(); 1780 } 1781 1782 void native_play_dead(void) 1783 { 1784 BUG(); 1785 } 1786 1787 #endif 1788 1789 #ifdef CONFIG_X86_64 1790 /* 1791 * APERF/MPERF frequency ratio computation. 1792 * 1793 * The scheduler wants to do frequency invariant accounting and needs a <1 1794 * ratio to account for the 'current' frequency, corresponding to 1795 * freq_curr / freq_max. 1796 * 1797 * Since the frequency freq_curr on x86 is controlled by micro-controller and 1798 * our P-state setting is little more than a request/hint, we need to observe 1799 * the effective frequency 'BusyMHz', i.e. the average frequency over a time 1800 * interval after discarding idle time. This is given by: 1801 * 1802 * BusyMHz = delta_APERF / delta_MPERF * freq_base 1803 * 1804 * where freq_base is the max non-turbo P-state. 1805 * 1806 * The freq_max term has to be set to a somewhat arbitrary value, because we 1807 * can't know which turbo states will be available at a given point in time: 1808 * it all depends on the thermal headroom of the entire package. We set it to 1809 * the turbo level with 4 cores active. 1810 * 1811 * Benchmarks show that's a good compromise between the 1C turbo ratio 1812 * (freq_curr/freq_max would rarely reach 1) and something close to freq_base, 1813 * which would ignore the entire turbo range (a conspicuous part, making 1814 * freq_curr/freq_max always maxed out). 1815 * 1816 * An exception to the heuristic above is the Atom uarch, where we choose the 1817 * highest turbo level for freq_max since Atom's are generally oriented towards 1818 * power efficiency. 1819 * 1820 * Setting freq_max to anything less than the 1C turbo ratio makes the ratio 1821 * freq_curr / freq_max to eventually grow >1, in which case we clip it to 1. 1822 */ 1823 1824 DEFINE_STATIC_KEY_FALSE(arch_scale_freq_key); 1825 1826 static DEFINE_PER_CPU(u64, arch_prev_aperf); 1827 static DEFINE_PER_CPU(u64, arch_prev_mperf); 1828 static u64 arch_turbo_freq_ratio = SCHED_CAPACITY_SCALE; 1829 static u64 arch_max_freq_ratio = SCHED_CAPACITY_SCALE; 1830 1831 void arch_set_max_freq_ratio(bool turbo_disabled) 1832 { 1833 arch_max_freq_ratio = turbo_disabled ? SCHED_CAPACITY_SCALE : 1834 arch_turbo_freq_ratio; 1835 } 1836 EXPORT_SYMBOL_GPL(arch_set_max_freq_ratio); 1837 1838 static bool turbo_disabled(void) 1839 { 1840 u64 misc_en; 1841 int err; 1842 1843 err = rdmsrl_safe(MSR_IA32_MISC_ENABLE, &misc_en); 1844 if (err) 1845 return false; 1846 1847 return (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE); 1848 } 1849 1850 static bool slv_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq) 1851 { 1852 int err; 1853 1854 err = rdmsrl_safe(MSR_ATOM_CORE_RATIOS, base_freq); 1855 if (err) 1856 return false; 1857 1858 err = rdmsrl_safe(MSR_ATOM_CORE_TURBO_RATIOS, turbo_freq); 1859 if (err) 1860 return false; 1861 1862 *base_freq = (*base_freq >> 16) & 0x3F; /* max P state */ 1863 *turbo_freq = *turbo_freq & 0x3F; /* 1C turbo */ 1864 1865 return true; 1866 } 1867 1868 #include <asm/cpu_device_id.h> 1869 #include <asm/intel-family.h> 1870 1871 #define X86_MATCH(model) \ 1872 X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, \ 1873 INTEL_FAM6_##model, X86_FEATURE_APERFMPERF, NULL) 1874 1875 static const struct x86_cpu_id has_knl_turbo_ratio_limits[] = { 1876 X86_MATCH(XEON_PHI_KNL), 1877 X86_MATCH(XEON_PHI_KNM), 1878 {} 1879 }; 1880 1881 static const struct x86_cpu_id has_skx_turbo_ratio_limits[] = { 1882 X86_MATCH(SKYLAKE_X), 1883 {} 1884 }; 1885 1886 static const struct x86_cpu_id has_glm_turbo_ratio_limits[] = { 1887 X86_MATCH(ATOM_GOLDMONT), 1888 X86_MATCH(ATOM_GOLDMONT_D), 1889 X86_MATCH(ATOM_GOLDMONT_PLUS), 1890 {} 1891 }; 1892 1893 static bool knl_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, 1894 int num_delta_fratio) 1895 { 1896 int fratio, delta_fratio, found; 1897 int err, i; 1898 u64 msr; 1899 1900 err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); 1901 if (err) 1902 return false; 1903 1904 *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ 1905 1906 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr); 1907 if (err) 1908 return false; 1909 1910 fratio = (msr >> 8) & 0xFF; 1911 i = 16; 1912 found = 0; 1913 do { 1914 if (found >= num_delta_fratio) { 1915 *turbo_freq = fratio; 1916 return true; 1917 } 1918 1919 delta_fratio = (msr >> (i + 5)) & 0x7; 1920 1921 if (delta_fratio) { 1922 found += 1; 1923 fratio -= delta_fratio; 1924 } 1925 1926 i += 8; 1927 } while (i < 64); 1928 1929 return true; 1930 } 1931 1932 static bool skx_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, int size) 1933 { 1934 u64 ratios, counts; 1935 u32 group_size; 1936 int err, i; 1937 1938 err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); 1939 if (err) 1940 return false; 1941 1942 *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ 1943 1944 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &ratios); 1945 if (err) 1946 return false; 1947 1948 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT1, &counts); 1949 if (err) 1950 return false; 1951 1952 for (i = 0; i < 64; i += 8) { 1953 group_size = (counts >> i) & 0xFF; 1954 if (group_size >= size) { 1955 *turbo_freq = (ratios >> i) & 0xFF; 1956 return true; 1957 } 1958 } 1959 1960 return false; 1961 } 1962 1963 static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq) 1964 { 1965 u64 msr; 1966 int err; 1967 1968 err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); 1969 if (err) 1970 return false; 1971 1972 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr); 1973 if (err) 1974 return false; 1975 1976 *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ 1977 *turbo_freq = (msr >> 24) & 0xFF; /* 4C turbo */ 1978 1979 /* The CPU may have less than 4 cores */ 1980 if (!*turbo_freq) 1981 *turbo_freq = msr & 0xFF; /* 1C turbo */ 1982 1983 return true; 1984 } 1985 1986 static bool intel_set_max_freq_ratio(void) 1987 { 1988 u64 base_freq, turbo_freq; 1989 u64 turbo_ratio; 1990 1991 if (slv_set_max_freq_ratio(&base_freq, &turbo_freq)) 1992 goto out; 1993 1994 if (x86_match_cpu(has_glm_turbo_ratio_limits) && 1995 skx_set_max_freq_ratio(&base_freq, &turbo_freq, 1)) 1996 goto out; 1997 1998 if (x86_match_cpu(has_knl_turbo_ratio_limits) && 1999 knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1)) 2000 goto out; 2001 2002 if (x86_match_cpu(has_skx_turbo_ratio_limits) && 2003 skx_set_max_freq_ratio(&base_freq, &turbo_freq, 4)) 2004 goto out; 2005 2006 if (core_set_max_freq_ratio(&base_freq, &turbo_freq)) 2007 goto out; 2008 2009 return false; 2010 2011 out: 2012 /* 2013 * Some hypervisors advertise X86_FEATURE_APERFMPERF 2014 * but then fill all MSR's with zeroes. 2015 * Some CPUs have turbo boost but don't declare any turbo ratio 2016 * in MSR_TURBO_RATIO_LIMIT. 2017 */ 2018 if (!base_freq || !turbo_freq) { 2019 pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting.\n"); 2020 return false; 2021 } 2022 2023 turbo_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, base_freq); 2024 if (!turbo_ratio) { 2025 pr_debug("Non-zero turbo and base frequencies led to a 0 ratio.\n"); 2026 return false; 2027 } 2028 2029 arch_turbo_freq_ratio = turbo_ratio; 2030 arch_set_max_freq_ratio(turbo_disabled()); 2031 2032 return true; 2033 } 2034 2035 #ifdef CONFIG_ACPI_CPPC_LIB 2036 static bool amd_set_max_freq_ratio(void) 2037 { 2038 struct cppc_perf_caps perf_caps; 2039 u64 highest_perf, nominal_perf; 2040 u64 perf_ratio; 2041 int rc; 2042 2043 rc = cppc_get_perf_caps(0, &perf_caps); 2044 if (rc) { 2045 pr_debug("Could not retrieve perf counters (%d)\n", rc); 2046 return false; 2047 } 2048 2049 highest_perf = perf_caps.highest_perf; 2050 nominal_perf = perf_caps.nominal_perf; 2051 2052 if (!highest_perf || !nominal_perf) { 2053 pr_debug("Could not retrieve highest or nominal performance\n"); 2054 return false; 2055 } 2056 2057 perf_ratio = div_u64(highest_perf * SCHED_CAPACITY_SCALE, nominal_perf); 2058 /* midpoint between max_boost and max_P */ 2059 perf_ratio = (perf_ratio + SCHED_CAPACITY_SCALE) >> 1; 2060 if (!perf_ratio) { 2061 pr_debug("Non-zero highest/nominal perf values led to a 0 ratio\n"); 2062 return false; 2063 } 2064 2065 arch_turbo_freq_ratio = perf_ratio; 2066 arch_set_max_freq_ratio(false); 2067 2068 return true; 2069 } 2070 #else 2071 static bool amd_set_max_freq_ratio(void) 2072 { 2073 return false; 2074 } 2075 #endif 2076 2077 static void init_counter_refs(void) 2078 { 2079 u64 aperf, mperf; 2080 2081 rdmsrl(MSR_IA32_APERF, aperf); 2082 rdmsrl(MSR_IA32_MPERF, mperf); 2083 2084 this_cpu_write(arch_prev_aperf, aperf); 2085 this_cpu_write(arch_prev_mperf, mperf); 2086 } 2087 2088 #ifdef CONFIG_PM_SLEEP 2089 static struct syscore_ops freq_invariance_syscore_ops = { 2090 .resume = init_counter_refs, 2091 }; 2092 2093 static void register_freq_invariance_syscore_ops(void) 2094 { 2095 /* Bail out if registered already. */ 2096 if (freq_invariance_syscore_ops.node.prev) 2097 return; 2098 2099 register_syscore_ops(&freq_invariance_syscore_ops); 2100 } 2101 #else 2102 static inline void register_freq_invariance_syscore_ops(void) {} 2103 #endif 2104 2105 static void init_freq_invariance(bool secondary, bool cppc_ready) 2106 { 2107 bool ret = false; 2108 2109 if (!boot_cpu_has(X86_FEATURE_APERFMPERF)) 2110 return; 2111 2112 if (secondary) { 2113 if (static_branch_likely(&arch_scale_freq_key)) { 2114 init_counter_refs(); 2115 } 2116 return; 2117 } 2118 2119 if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) 2120 ret = intel_set_max_freq_ratio(); 2121 else if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) { 2122 if (!cppc_ready) { 2123 return; 2124 } 2125 ret = amd_set_max_freq_ratio(); 2126 } 2127 2128 if (ret) { 2129 init_counter_refs(); 2130 static_branch_enable(&arch_scale_freq_key); 2131 register_freq_invariance_syscore_ops(); 2132 pr_info("Estimated ratio of average max frequency by base frequency (times 1024): %llu\n", arch_max_freq_ratio); 2133 } else { 2134 pr_debug("Couldn't determine max cpu frequency, necessary for scale-invariant accounting.\n"); 2135 } 2136 } 2137 2138 #ifdef CONFIG_ACPI_CPPC_LIB 2139 static DEFINE_MUTEX(freq_invariance_lock); 2140 2141 void init_freq_invariance_cppc(void) 2142 { 2143 static bool secondary; 2144 2145 mutex_lock(&freq_invariance_lock); 2146 2147 init_freq_invariance(secondary, true); 2148 secondary = true; 2149 2150 mutex_unlock(&freq_invariance_lock); 2151 } 2152 #endif 2153 2154 static void disable_freq_invariance_workfn(struct work_struct *work) 2155 { 2156 static_branch_disable(&arch_scale_freq_key); 2157 } 2158 2159 static DECLARE_WORK(disable_freq_invariance_work, 2160 disable_freq_invariance_workfn); 2161 2162 DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE; 2163 2164 void arch_scale_freq_tick(void) 2165 { 2166 u64 freq_scale = SCHED_CAPACITY_SCALE; 2167 u64 aperf, mperf; 2168 u64 acnt, mcnt; 2169 2170 if (!arch_scale_freq_invariant()) 2171 return; 2172 2173 rdmsrl(MSR_IA32_APERF, aperf); 2174 rdmsrl(MSR_IA32_MPERF, mperf); 2175 2176 acnt = aperf - this_cpu_read(arch_prev_aperf); 2177 mcnt = mperf - this_cpu_read(arch_prev_mperf); 2178 2179 this_cpu_write(arch_prev_aperf, aperf); 2180 this_cpu_write(arch_prev_mperf, mperf); 2181 2182 if (check_shl_overflow(acnt, 2*SCHED_CAPACITY_SHIFT, &acnt)) 2183 goto error; 2184 2185 if (check_mul_overflow(mcnt, arch_max_freq_ratio, &mcnt) || !mcnt) 2186 goto error; 2187 2188 freq_scale = div64_u64(acnt, mcnt); 2189 if (!freq_scale) 2190 goto error; 2191 2192 if (freq_scale > SCHED_CAPACITY_SCALE) 2193 freq_scale = SCHED_CAPACITY_SCALE; 2194 2195 this_cpu_write(arch_freq_scale, freq_scale); 2196 return; 2197 2198 error: 2199 pr_warn("Scheduler frequency invariance went wobbly, disabling!\n"); 2200 schedule_work(&disable_freq_invariance_work); 2201 } 2202 #else 2203 static inline void init_freq_invariance(bool secondary, bool cppc_ready) 2204 { 2205 } 2206 #endif /* CONFIG_X86_64 */ 2207