1 /* 2 * arch/s390/kernel/smp.c 3 * 4 * Copyright IBM Corp. 1999, 2009 5 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), 6 * Martin Schwidefsky (schwidefsky@de.ibm.com) 7 * Heiko Carstens (heiko.carstens@de.ibm.com) 8 * 9 * based on other smp stuff by 10 * (c) 1995 Alan Cox, CymruNET Ltd <alan@cymru.net> 11 * (c) 1998 Ingo Molnar 12 * 13 * We work with logical cpu numbering everywhere we can. The only 14 * functions using the real cpu address (got from STAP) are the sigp 15 * functions. For all other functions we use the identity mapping. 16 * That means that cpu_number_map[i] == i for every cpu. cpu_number_map is 17 * used e.g. to find the idle task belonging to a logical cpu. Every array 18 * in the kernel is sorted by the logical cpu number and not by the physical 19 * one which is causing all the confusion with __cpu_logical_map and 20 * cpu_number_map in other architectures. 21 */ 22 23 #define KMSG_COMPONENT "cpu" 24 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 25 26 #include <linux/module.h> 27 #include <linux/init.h> 28 #include <linux/mm.h> 29 #include <linux/err.h> 30 #include <linux/spinlock.h> 31 #include <linux/kernel_stat.h> 32 #include <linux/delay.h> 33 #include <linux/cache.h> 34 #include <linux/interrupt.h> 35 #include <linux/irqflags.h> 36 #include <linux/cpu.h> 37 #include <linux/timex.h> 38 #include <linux/bootmem.h> 39 #include <asm/ipl.h> 40 #include <asm/setup.h> 41 #include <asm/sigp.h> 42 #include <asm/pgalloc.h> 43 #include <asm/irq.h> 44 #include <asm/s390_ext.h> 45 #include <asm/cpcmd.h> 46 #include <asm/tlbflush.h> 47 #include <asm/timer.h> 48 #include <asm/lowcore.h> 49 #include <asm/sclp.h> 50 #include <asm/cputime.h> 51 #include <asm/vdso.h> 52 #include "entry.h" 53 54 static struct task_struct *current_set[NR_CPUS]; 55 56 static u8 smp_cpu_type; 57 static int smp_use_sigp_detection; 58 59 enum s390_cpu_state { 60 CPU_STATE_STANDBY, 61 CPU_STATE_CONFIGURED, 62 }; 63 64 DEFINE_MUTEX(smp_cpu_state_mutex); 65 int smp_cpu_polarization[NR_CPUS]; 66 static int smp_cpu_state[NR_CPUS]; 67 static int cpu_management; 68 69 static DEFINE_PER_CPU(struct cpu, cpu_devices); 70 71 static void smp_ext_bitcall(int, ec_bit_sig); 72 73 void smp_send_stop(void) 74 { 75 int cpu, rc; 76 77 /* Disable all interrupts/machine checks */ 78 __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK); 79 trace_hardirqs_off(); 80 81 /* stop all processors */ 82 for_each_online_cpu(cpu) { 83 if (cpu == smp_processor_id()) 84 continue; 85 do { 86 rc = signal_processor(cpu, sigp_stop); 87 } while (rc == sigp_busy); 88 89 while (!smp_cpu_not_running(cpu)) 90 cpu_relax(); 91 } 92 } 93 94 /* 95 * This is the main routine where commands issued by other 96 * cpus are handled. 97 */ 98 99 static void do_ext_call_interrupt(__u16 code) 100 { 101 unsigned long bits; 102 103 /* 104 * handle bit signal external calls 105 * 106 * For the ec_schedule signal we have to do nothing. All the work 107 * is done automatically when we return from the interrupt. 108 */ 109 bits = xchg(&S390_lowcore.ext_call_fast, 0); 110 111 if (test_bit(ec_call_function, &bits)) 112 generic_smp_call_function_interrupt(); 113 114 if (test_bit(ec_call_function_single, &bits)) 115 generic_smp_call_function_single_interrupt(); 116 } 117 118 /* 119 * Send an external call sigp to another cpu and return without waiting 120 * for its completion. 121 */ 122 static void smp_ext_bitcall(int cpu, ec_bit_sig sig) 123 { 124 /* 125 * Set signaling bit in lowcore of target cpu and kick it 126 */ 127 set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast); 128 while (signal_processor(cpu, sigp_emergency_signal) == sigp_busy) 129 udelay(10); 130 } 131 132 void arch_send_call_function_ipi(cpumask_t mask) 133 { 134 int cpu; 135 136 for_each_cpu_mask(cpu, mask) 137 smp_ext_bitcall(cpu, ec_call_function); 138 } 139 140 void arch_send_call_function_single_ipi(int cpu) 141 { 142 smp_ext_bitcall(cpu, ec_call_function_single); 143 } 144 145 #ifndef CONFIG_64BIT 146 /* 147 * this function sends a 'purge tlb' signal to another CPU. 148 */ 149 static void smp_ptlb_callback(void *info) 150 { 151 __tlb_flush_local(); 152 } 153 154 void smp_ptlb_all(void) 155 { 156 on_each_cpu(smp_ptlb_callback, NULL, 1); 157 } 158 EXPORT_SYMBOL(smp_ptlb_all); 159 #endif /* ! CONFIG_64BIT */ 160 161 /* 162 * this function sends a 'reschedule' IPI to another CPU. 163 * it goes straight through and wastes no time serializing 164 * anything. Worst case is that we lose a reschedule ... 165 */ 166 void smp_send_reschedule(int cpu) 167 { 168 smp_ext_bitcall(cpu, ec_schedule); 169 } 170 171 /* 172 * parameter area for the set/clear control bit callbacks 173 */ 174 struct ec_creg_mask_parms { 175 unsigned long orvals[16]; 176 unsigned long andvals[16]; 177 }; 178 179 /* 180 * callback for setting/clearing control bits 181 */ 182 static void smp_ctl_bit_callback(void *info) 183 { 184 struct ec_creg_mask_parms *pp = info; 185 unsigned long cregs[16]; 186 int i; 187 188 __ctl_store(cregs, 0, 15); 189 for (i = 0; i <= 15; i++) 190 cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i]; 191 __ctl_load(cregs, 0, 15); 192 } 193 194 /* 195 * Set a bit in a control register of all cpus 196 */ 197 void smp_ctl_set_bit(int cr, int bit) 198 { 199 struct ec_creg_mask_parms parms; 200 201 memset(&parms.orvals, 0, sizeof(parms.orvals)); 202 memset(&parms.andvals, 0xff, sizeof(parms.andvals)); 203 parms.orvals[cr] = 1 << bit; 204 on_each_cpu(smp_ctl_bit_callback, &parms, 1); 205 } 206 EXPORT_SYMBOL(smp_ctl_set_bit); 207 208 /* 209 * Clear a bit in a control register of all cpus 210 */ 211 void smp_ctl_clear_bit(int cr, int bit) 212 { 213 struct ec_creg_mask_parms parms; 214 215 memset(&parms.orvals, 0, sizeof(parms.orvals)); 216 memset(&parms.andvals, 0xff, sizeof(parms.andvals)); 217 parms.andvals[cr] = ~(1L << bit); 218 on_each_cpu(smp_ctl_bit_callback, &parms, 1); 219 } 220 EXPORT_SYMBOL(smp_ctl_clear_bit); 221 222 /* 223 * In early ipl state a temp. logically cpu number is needed, so the sigp 224 * functions can be used to sense other cpus. Since NR_CPUS is >= 2 on 225 * CONFIG_SMP and the ipl cpu is logical cpu 0, it must be 1. 226 */ 227 #define CPU_INIT_NO 1 228 229 #ifdef CONFIG_ZFCPDUMP 230 231 /* 232 * zfcpdump_prefix_array holds prefix registers for the following scenario: 233 * 64 bit zfcpdump kernel and 31 bit kernel which is to be dumped. We have to 234 * save its prefix registers, since they get lost, when switching from 31 bit 235 * to 64 bit. 236 */ 237 unsigned int zfcpdump_prefix_array[NR_CPUS + 1] \ 238 __attribute__((__section__(".data"))); 239 240 static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) 241 { 242 if (ipl_info.type != IPL_TYPE_FCP_DUMP) 243 return; 244 if (cpu >= NR_CPUS) { 245 pr_warning("CPU %i exceeds the maximum %i and is excluded from " 246 "the dump\n", cpu, NR_CPUS - 1); 247 return; 248 } 249 zfcpdump_save_areas[cpu] = kmalloc(sizeof(union save_area), GFP_KERNEL); 250 __cpu_logical_map[CPU_INIT_NO] = (__u16) phy_cpu; 251 while (signal_processor(CPU_INIT_NO, sigp_stop_and_store_status) == 252 sigp_busy) 253 cpu_relax(); 254 memcpy(zfcpdump_save_areas[cpu], 255 (void *)(unsigned long) store_prefix() + SAVE_AREA_BASE, 256 SAVE_AREA_SIZE); 257 #ifdef CONFIG_64BIT 258 /* copy original prefix register */ 259 zfcpdump_save_areas[cpu]->s390x.pref_reg = zfcpdump_prefix_array[cpu]; 260 #endif 261 } 262 263 union save_area *zfcpdump_save_areas[NR_CPUS + 1]; 264 EXPORT_SYMBOL_GPL(zfcpdump_save_areas); 265 266 #else 267 268 static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { } 269 270 #endif /* CONFIG_ZFCPDUMP */ 271 272 static int cpu_stopped(int cpu) 273 { 274 __u32 status; 275 276 /* Check for stopped state */ 277 if (signal_processor_ps(&status, 0, cpu, sigp_sense) == 278 sigp_status_stored) { 279 if (status & 0x40) 280 return 1; 281 } 282 return 0; 283 } 284 285 static int cpu_known(int cpu_id) 286 { 287 int cpu; 288 289 for_each_present_cpu(cpu) { 290 if (__cpu_logical_map[cpu] == cpu_id) 291 return 1; 292 } 293 return 0; 294 } 295 296 static int smp_rescan_cpus_sigp(cpumask_t avail) 297 { 298 int cpu_id, logical_cpu; 299 300 logical_cpu = cpumask_first(&avail); 301 if (logical_cpu >= nr_cpu_ids) 302 return 0; 303 for (cpu_id = 0; cpu_id <= 65535; cpu_id++) { 304 if (cpu_known(cpu_id)) 305 continue; 306 __cpu_logical_map[logical_cpu] = cpu_id; 307 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN; 308 if (!cpu_stopped(logical_cpu)) 309 continue; 310 cpu_set(logical_cpu, cpu_present_map); 311 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; 312 logical_cpu = cpumask_next(logical_cpu, &avail); 313 if (logical_cpu >= nr_cpu_ids) 314 break; 315 } 316 return 0; 317 } 318 319 static int smp_rescan_cpus_sclp(cpumask_t avail) 320 { 321 struct sclp_cpu_info *info; 322 int cpu_id, logical_cpu, cpu; 323 int rc; 324 325 logical_cpu = cpumask_first(&avail); 326 if (logical_cpu >= nr_cpu_ids) 327 return 0; 328 info = kmalloc(sizeof(*info), GFP_KERNEL); 329 if (!info) 330 return -ENOMEM; 331 rc = sclp_get_cpu_info(info); 332 if (rc) 333 goto out; 334 for (cpu = 0; cpu < info->combined; cpu++) { 335 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) 336 continue; 337 cpu_id = info->cpu[cpu].address; 338 if (cpu_known(cpu_id)) 339 continue; 340 __cpu_logical_map[logical_cpu] = cpu_id; 341 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN; 342 cpu_set(logical_cpu, cpu_present_map); 343 if (cpu >= info->configured) 344 smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY; 345 else 346 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; 347 logical_cpu = cpumask_next(logical_cpu, &avail); 348 if (logical_cpu >= nr_cpu_ids) 349 break; 350 } 351 out: 352 kfree(info); 353 return rc; 354 } 355 356 static int __smp_rescan_cpus(void) 357 { 358 cpumask_t avail; 359 360 cpus_xor(avail, cpu_possible_map, cpu_present_map); 361 if (smp_use_sigp_detection) 362 return smp_rescan_cpus_sigp(avail); 363 else 364 return smp_rescan_cpus_sclp(avail); 365 } 366 367 static void __init smp_detect_cpus(void) 368 { 369 unsigned int cpu, c_cpus, s_cpus; 370 struct sclp_cpu_info *info; 371 u16 boot_cpu_addr, cpu_addr; 372 373 c_cpus = 1; 374 s_cpus = 0; 375 boot_cpu_addr = __cpu_logical_map[0]; 376 info = kmalloc(sizeof(*info), GFP_KERNEL); 377 if (!info) 378 panic("smp_detect_cpus failed to allocate memory\n"); 379 /* Use sigp detection algorithm if sclp doesn't work. */ 380 if (sclp_get_cpu_info(info)) { 381 smp_use_sigp_detection = 1; 382 for (cpu = 0; cpu <= 65535; cpu++) { 383 if (cpu == boot_cpu_addr) 384 continue; 385 __cpu_logical_map[CPU_INIT_NO] = cpu; 386 if (!cpu_stopped(CPU_INIT_NO)) 387 continue; 388 smp_get_save_area(c_cpus, cpu); 389 c_cpus++; 390 } 391 goto out; 392 } 393 394 if (info->has_cpu_type) { 395 for (cpu = 0; cpu < info->combined; cpu++) { 396 if (info->cpu[cpu].address == boot_cpu_addr) { 397 smp_cpu_type = info->cpu[cpu].type; 398 break; 399 } 400 } 401 } 402 403 for (cpu = 0; cpu < info->combined; cpu++) { 404 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) 405 continue; 406 cpu_addr = info->cpu[cpu].address; 407 if (cpu_addr == boot_cpu_addr) 408 continue; 409 __cpu_logical_map[CPU_INIT_NO] = cpu_addr; 410 if (!cpu_stopped(CPU_INIT_NO)) { 411 s_cpus++; 412 continue; 413 } 414 smp_get_save_area(c_cpus, cpu_addr); 415 c_cpus++; 416 } 417 out: 418 kfree(info); 419 pr_info("%d configured CPUs, %d standby CPUs\n", c_cpus, s_cpus); 420 get_online_cpus(); 421 __smp_rescan_cpus(); 422 put_online_cpus(); 423 } 424 425 /* 426 * Activate a secondary processor. 427 */ 428 int __cpuinit start_secondary(void *cpuvoid) 429 { 430 /* Setup the cpu */ 431 cpu_init(); 432 preempt_disable(); 433 /* Enable TOD clock interrupts on the secondary cpu. */ 434 init_cpu_timer(); 435 /* Enable cpu timer interrupts on the secondary cpu. */ 436 init_cpu_vtimer(); 437 /* Enable pfault pseudo page faults on this cpu. */ 438 pfault_init(); 439 440 /* call cpu notifiers */ 441 notify_cpu_starting(smp_processor_id()); 442 /* Mark this cpu as online */ 443 ipi_call_lock(); 444 cpu_set(smp_processor_id(), cpu_online_map); 445 ipi_call_unlock(); 446 /* Switch on interrupts */ 447 local_irq_enable(); 448 /* Print info about this processor */ 449 print_cpu_info(); 450 /* cpu_idle will call schedule for us */ 451 cpu_idle(); 452 return 0; 453 } 454 455 static void __init smp_create_idle(unsigned int cpu) 456 { 457 struct task_struct *p; 458 459 /* 460 * don't care about the psw and regs settings since we'll never 461 * reschedule the forked task. 462 */ 463 p = fork_idle(cpu); 464 if (IS_ERR(p)) 465 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p)); 466 current_set[cpu] = p; 467 } 468 469 static int __cpuinit smp_alloc_lowcore(int cpu) 470 { 471 unsigned long async_stack, panic_stack; 472 struct _lowcore *lowcore; 473 int lc_order; 474 475 lc_order = sizeof(long) == 8 ? 1 : 0; 476 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order); 477 if (!lowcore) 478 return -ENOMEM; 479 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); 480 panic_stack = __get_free_page(GFP_KERNEL); 481 if (!panic_stack || !async_stack) 482 goto out; 483 memcpy(lowcore, &S390_lowcore, 512); 484 memset((char *)lowcore + 512, 0, sizeof(*lowcore) - 512); 485 lowcore->async_stack = async_stack + ASYNC_SIZE; 486 lowcore->panic_stack = panic_stack + PAGE_SIZE; 487 488 #ifndef CONFIG_64BIT 489 if (MACHINE_HAS_IEEE) { 490 unsigned long save_area; 491 492 save_area = get_zeroed_page(GFP_KERNEL); 493 if (!save_area) 494 goto out; 495 lowcore->extended_save_area_addr = (u32) save_area; 496 } 497 #else 498 if (vdso_alloc_per_cpu(cpu, lowcore)) 499 goto out; 500 #endif 501 lowcore_ptr[cpu] = lowcore; 502 return 0; 503 504 out: 505 free_page(panic_stack); 506 free_pages(async_stack, ASYNC_ORDER); 507 free_pages((unsigned long) lowcore, lc_order); 508 return -ENOMEM; 509 } 510 511 static void smp_free_lowcore(int cpu) 512 { 513 struct _lowcore *lowcore; 514 int lc_order; 515 516 lc_order = sizeof(long) == 8 ? 1 : 0; 517 lowcore = lowcore_ptr[cpu]; 518 #ifndef CONFIG_64BIT 519 if (MACHINE_HAS_IEEE) 520 free_page((unsigned long) lowcore->extended_save_area_addr); 521 #else 522 vdso_free_per_cpu(cpu, lowcore); 523 #endif 524 free_page(lowcore->panic_stack - PAGE_SIZE); 525 free_pages(lowcore->async_stack - ASYNC_SIZE, ASYNC_ORDER); 526 free_pages((unsigned long) lowcore, lc_order); 527 lowcore_ptr[cpu] = NULL; 528 } 529 530 /* Upping and downing of CPUs */ 531 int __cpuinit __cpu_up(unsigned int cpu) 532 { 533 struct task_struct *idle; 534 struct _lowcore *cpu_lowcore; 535 struct stack_frame *sf; 536 sigp_ccode ccode; 537 u32 lowcore; 538 539 if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED) 540 return -EIO; 541 if (smp_alloc_lowcore(cpu)) 542 return -ENOMEM; 543 do { 544 ccode = signal_processor(cpu, sigp_initial_cpu_reset); 545 if (ccode == sigp_busy) 546 udelay(10); 547 if (ccode == sigp_not_operational) 548 goto err_out; 549 } while (ccode == sigp_busy); 550 551 lowcore = (u32)(unsigned long)lowcore_ptr[cpu]; 552 while (signal_processor_p(lowcore, cpu, sigp_set_prefix) == sigp_busy) 553 udelay(10); 554 555 idle = current_set[cpu]; 556 cpu_lowcore = lowcore_ptr[cpu]; 557 cpu_lowcore->kernel_stack = (unsigned long) 558 task_stack_page(idle) + THREAD_SIZE; 559 cpu_lowcore->thread_info = (unsigned long) task_thread_info(idle); 560 sf = (struct stack_frame *) (cpu_lowcore->kernel_stack 561 - sizeof(struct pt_regs) 562 - sizeof(struct stack_frame)); 563 memset(sf, 0, sizeof(struct stack_frame)); 564 sf->gprs[9] = (unsigned long) sf; 565 cpu_lowcore->save_area[15] = (unsigned long) sf; 566 __ctl_store(cpu_lowcore->cregs_save_area, 0, 15); 567 asm volatile( 568 " stam 0,15,0(%0)" 569 : : "a" (&cpu_lowcore->access_regs_save_area) : "memory"); 570 cpu_lowcore->percpu_offset = __per_cpu_offset[cpu]; 571 cpu_lowcore->current_task = (unsigned long) idle; 572 cpu_lowcore->cpu_nr = cpu; 573 cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce; 574 cpu_lowcore->machine_flags = S390_lowcore.machine_flags; 575 cpu_lowcore->ftrace_func = S390_lowcore.ftrace_func; 576 eieio(); 577 578 while (signal_processor(cpu, sigp_restart) == sigp_busy) 579 udelay(10); 580 581 while (!cpu_online(cpu)) 582 cpu_relax(); 583 return 0; 584 585 err_out: 586 smp_free_lowcore(cpu); 587 return -EIO; 588 } 589 590 static int __init setup_possible_cpus(char *s) 591 { 592 int pcpus, cpu; 593 594 pcpus = simple_strtoul(s, NULL, 0); 595 init_cpu_possible(cpumask_of(0)); 596 for (cpu = 1; cpu < pcpus && cpu < nr_cpu_ids; cpu++) 597 set_cpu_possible(cpu, true); 598 return 0; 599 } 600 early_param("possible_cpus", setup_possible_cpus); 601 602 #ifdef CONFIG_HOTPLUG_CPU 603 604 int __cpu_disable(void) 605 { 606 struct ec_creg_mask_parms cr_parms; 607 int cpu = smp_processor_id(); 608 609 cpu_clear(cpu, cpu_online_map); 610 611 /* Disable pfault pseudo page faults on this cpu. */ 612 pfault_fini(); 613 614 memset(&cr_parms.orvals, 0, sizeof(cr_parms.orvals)); 615 memset(&cr_parms.andvals, 0xff, sizeof(cr_parms.andvals)); 616 617 /* disable all external interrupts */ 618 cr_parms.orvals[0] = 0; 619 cr_parms.andvals[0] = ~(1 << 15 | 1 << 14 | 1 << 13 | 1 << 12 | 620 1 << 11 | 1 << 10 | 1 << 6 | 1 << 4); 621 /* disable all I/O interrupts */ 622 cr_parms.orvals[6] = 0; 623 cr_parms.andvals[6] = ~(1 << 31 | 1 << 30 | 1 << 29 | 1 << 28 | 624 1 << 27 | 1 << 26 | 1 << 25 | 1 << 24); 625 /* disable most machine checks */ 626 cr_parms.orvals[14] = 0; 627 cr_parms.andvals[14] = ~(1 << 28 | 1 << 27 | 1 << 26 | 628 1 << 25 | 1 << 24); 629 630 smp_ctl_bit_callback(&cr_parms); 631 632 return 0; 633 } 634 635 void __cpu_die(unsigned int cpu) 636 { 637 /* Wait until target cpu is down */ 638 while (!smp_cpu_not_running(cpu)) 639 cpu_relax(); 640 smp_free_lowcore(cpu); 641 pr_info("Processor %d stopped\n", cpu); 642 } 643 644 void cpu_die(void) 645 { 646 idle_task_exit(); 647 signal_processor(smp_processor_id(), sigp_stop); 648 BUG(); 649 for (;;); 650 } 651 652 #endif /* CONFIG_HOTPLUG_CPU */ 653 654 void __init smp_prepare_cpus(unsigned int max_cpus) 655 { 656 #ifndef CONFIG_64BIT 657 unsigned long save_area = 0; 658 #endif 659 unsigned long async_stack, panic_stack; 660 struct _lowcore *lowcore; 661 unsigned int cpu; 662 int lc_order; 663 664 smp_detect_cpus(); 665 666 /* request the 0x1201 emergency signal external interrupt */ 667 if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0) 668 panic("Couldn't request external interrupt 0x1201"); 669 print_cpu_info(); 670 671 /* Reallocate current lowcore, but keep its contents. */ 672 lc_order = sizeof(long) == 8 ? 1 : 0; 673 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order); 674 panic_stack = __get_free_page(GFP_KERNEL); 675 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); 676 BUG_ON(!lowcore || !panic_stack || !async_stack); 677 #ifndef CONFIG_64BIT 678 if (MACHINE_HAS_IEEE) 679 save_area = get_zeroed_page(GFP_KERNEL); 680 #endif 681 local_irq_disable(); 682 local_mcck_disable(); 683 lowcore_ptr[smp_processor_id()] = lowcore; 684 *lowcore = S390_lowcore; 685 lowcore->panic_stack = panic_stack + PAGE_SIZE; 686 lowcore->async_stack = async_stack + ASYNC_SIZE; 687 #ifndef CONFIG_64BIT 688 if (MACHINE_HAS_IEEE) 689 lowcore->extended_save_area_addr = (u32) save_area; 690 #else 691 if (vdso_alloc_per_cpu(smp_processor_id(), lowcore)) 692 BUG(); 693 #endif 694 set_prefix((u32)(unsigned long) lowcore); 695 local_mcck_enable(); 696 local_irq_enable(); 697 for_each_possible_cpu(cpu) 698 if (cpu != smp_processor_id()) 699 smp_create_idle(cpu); 700 } 701 702 void __init smp_prepare_boot_cpu(void) 703 { 704 BUG_ON(smp_processor_id() != 0); 705 706 current_thread_info()->cpu = 0; 707 cpu_set(0, cpu_present_map); 708 cpu_set(0, cpu_online_map); 709 S390_lowcore.percpu_offset = __per_cpu_offset[0]; 710 current_set[0] = current; 711 smp_cpu_state[0] = CPU_STATE_CONFIGURED; 712 smp_cpu_polarization[0] = POLARIZATION_UNKNWN; 713 } 714 715 void __init smp_cpus_done(unsigned int max_cpus) 716 { 717 } 718 719 /* 720 * the frequency of the profiling timer can be changed 721 * by writing a multiplier value into /proc/profile. 722 * 723 * usually you want to run this on all CPUs ;) 724 */ 725 int setup_profiling_timer(unsigned int multiplier) 726 { 727 return 0; 728 } 729 730 #ifdef CONFIG_HOTPLUG_CPU 731 static ssize_t cpu_configure_show(struct sys_device *dev, 732 struct sysdev_attribute *attr, char *buf) 733 { 734 ssize_t count; 735 736 mutex_lock(&smp_cpu_state_mutex); 737 count = sprintf(buf, "%d\n", smp_cpu_state[dev->id]); 738 mutex_unlock(&smp_cpu_state_mutex); 739 return count; 740 } 741 742 static ssize_t cpu_configure_store(struct sys_device *dev, 743 struct sysdev_attribute *attr, 744 const char *buf, size_t count) 745 { 746 int cpu = dev->id; 747 int val, rc; 748 char delim; 749 750 if (sscanf(buf, "%d %c", &val, &delim) != 1) 751 return -EINVAL; 752 if (val != 0 && val != 1) 753 return -EINVAL; 754 755 get_online_cpus(); 756 mutex_lock(&smp_cpu_state_mutex); 757 rc = -EBUSY; 758 if (cpu_online(cpu)) 759 goto out; 760 rc = 0; 761 switch (val) { 762 case 0: 763 if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) { 764 rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]); 765 if (!rc) { 766 smp_cpu_state[cpu] = CPU_STATE_STANDBY; 767 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN; 768 } 769 } 770 break; 771 case 1: 772 if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) { 773 rc = sclp_cpu_configure(__cpu_logical_map[cpu]); 774 if (!rc) { 775 smp_cpu_state[cpu] = CPU_STATE_CONFIGURED; 776 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN; 777 } 778 } 779 break; 780 default: 781 break; 782 } 783 out: 784 mutex_unlock(&smp_cpu_state_mutex); 785 put_online_cpus(); 786 return rc ? rc : count; 787 } 788 static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store); 789 #endif /* CONFIG_HOTPLUG_CPU */ 790 791 static ssize_t cpu_polarization_show(struct sys_device *dev, 792 struct sysdev_attribute *attr, char *buf) 793 { 794 int cpu = dev->id; 795 ssize_t count; 796 797 mutex_lock(&smp_cpu_state_mutex); 798 switch (smp_cpu_polarization[cpu]) { 799 case POLARIZATION_HRZ: 800 count = sprintf(buf, "horizontal\n"); 801 break; 802 case POLARIZATION_VL: 803 count = sprintf(buf, "vertical:low\n"); 804 break; 805 case POLARIZATION_VM: 806 count = sprintf(buf, "vertical:medium\n"); 807 break; 808 case POLARIZATION_VH: 809 count = sprintf(buf, "vertical:high\n"); 810 break; 811 default: 812 count = sprintf(buf, "unknown\n"); 813 break; 814 } 815 mutex_unlock(&smp_cpu_state_mutex); 816 return count; 817 } 818 static SYSDEV_ATTR(polarization, 0444, cpu_polarization_show, NULL); 819 820 static ssize_t show_cpu_address(struct sys_device *dev, 821 struct sysdev_attribute *attr, char *buf) 822 { 823 return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]); 824 } 825 static SYSDEV_ATTR(address, 0444, show_cpu_address, NULL); 826 827 828 static struct attribute *cpu_common_attrs[] = { 829 #ifdef CONFIG_HOTPLUG_CPU 830 &attr_configure.attr, 831 #endif 832 &attr_address.attr, 833 &attr_polarization.attr, 834 NULL, 835 }; 836 837 static struct attribute_group cpu_common_attr_group = { 838 .attrs = cpu_common_attrs, 839 }; 840 841 static ssize_t show_capability(struct sys_device *dev, 842 struct sysdev_attribute *attr, char *buf) 843 { 844 unsigned int capability; 845 int rc; 846 847 rc = get_cpu_capability(&capability); 848 if (rc) 849 return rc; 850 return sprintf(buf, "%u\n", capability); 851 } 852 static SYSDEV_ATTR(capability, 0444, show_capability, NULL); 853 854 static ssize_t show_idle_count(struct sys_device *dev, 855 struct sysdev_attribute *attr, char *buf) 856 { 857 struct s390_idle_data *idle; 858 unsigned long long idle_count; 859 unsigned int sequence; 860 861 idle = &per_cpu(s390_idle, dev->id); 862 repeat: 863 sequence = idle->sequence; 864 smp_rmb(); 865 if (sequence & 1) 866 goto repeat; 867 idle_count = idle->idle_count; 868 if (idle->idle_enter) 869 idle_count++; 870 smp_rmb(); 871 if (idle->sequence != sequence) 872 goto repeat; 873 return sprintf(buf, "%llu\n", idle_count); 874 } 875 static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL); 876 877 static ssize_t show_idle_time(struct sys_device *dev, 878 struct sysdev_attribute *attr, char *buf) 879 { 880 struct s390_idle_data *idle; 881 unsigned long long now, idle_time, idle_enter; 882 unsigned int sequence; 883 884 idle = &per_cpu(s390_idle, dev->id); 885 now = get_clock(); 886 repeat: 887 sequence = idle->sequence; 888 smp_rmb(); 889 if (sequence & 1) 890 goto repeat; 891 idle_time = idle->idle_time; 892 idle_enter = idle->idle_enter; 893 if (idle_enter != 0ULL && idle_enter < now) 894 idle_time += now - idle_enter; 895 smp_rmb(); 896 if (idle->sequence != sequence) 897 goto repeat; 898 return sprintf(buf, "%llu\n", idle_time >> 12); 899 } 900 static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL); 901 902 static struct attribute *cpu_online_attrs[] = { 903 &attr_capability.attr, 904 &attr_idle_count.attr, 905 &attr_idle_time_us.attr, 906 NULL, 907 }; 908 909 static struct attribute_group cpu_online_attr_group = { 910 .attrs = cpu_online_attrs, 911 }; 912 913 static int __cpuinit smp_cpu_notify(struct notifier_block *self, 914 unsigned long action, void *hcpu) 915 { 916 unsigned int cpu = (unsigned int)(long)hcpu; 917 struct cpu *c = &per_cpu(cpu_devices, cpu); 918 struct sys_device *s = &c->sysdev; 919 struct s390_idle_data *idle; 920 921 switch (action) { 922 case CPU_ONLINE: 923 case CPU_ONLINE_FROZEN: 924 idle = &per_cpu(s390_idle, cpu); 925 memset(idle, 0, sizeof(struct s390_idle_data)); 926 if (sysfs_create_group(&s->kobj, &cpu_online_attr_group)) 927 return NOTIFY_BAD; 928 break; 929 case CPU_DEAD: 930 case CPU_DEAD_FROZEN: 931 sysfs_remove_group(&s->kobj, &cpu_online_attr_group); 932 break; 933 } 934 return NOTIFY_OK; 935 } 936 937 static struct notifier_block __cpuinitdata smp_cpu_nb = { 938 .notifier_call = smp_cpu_notify, 939 }; 940 941 static int __devinit smp_add_present_cpu(int cpu) 942 { 943 struct cpu *c = &per_cpu(cpu_devices, cpu); 944 struct sys_device *s = &c->sysdev; 945 int rc; 946 947 c->hotpluggable = 1; 948 rc = register_cpu(c, cpu); 949 if (rc) 950 goto out; 951 rc = sysfs_create_group(&s->kobj, &cpu_common_attr_group); 952 if (rc) 953 goto out_cpu; 954 if (!cpu_online(cpu)) 955 goto out; 956 rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group); 957 if (!rc) 958 return 0; 959 sysfs_remove_group(&s->kobj, &cpu_common_attr_group); 960 out_cpu: 961 #ifdef CONFIG_HOTPLUG_CPU 962 unregister_cpu(c); 963 #endif 964 out: 965 return rc; 966 } 967 968 #ifdef CONFIG_HOTPLUG_CPU 969 970 int __ref smp_rescan_cpus(void) 971 { 972 cpumask_t newcpus; 973 int cpu; 974 int rc; 975 976 get_online_cpus(); 977 mutex_lock(&smp_cpu_state_mutex); 978 newcpus = cpu_present_map; 979 rc = __smp_rescan_cpus(); 980 if (rc) 981 goto out; 982 cpus_andnot(newcpus, cpu_present_map, newcpus); 983 for_each_cpu_mask(cpu, newcpus) { 984 rc = smp_add_present_cpu(cpu); 985 if (rc) 986 cpu_clear(cpu, cpu_present_map); 987 } 988 rc = 0; 989 out: 990 mutex_unlock(&smp_cpu_state_mutex); 991 put_online_cpus(); 992 if (!cpus_empty(newcpus)) 993 topology_schedule_update(); 994 return rc; 995 } 996 997 static ssize_t __ref rescan_store(struct sysdev_class *class, const char *buf, 998 size_t count) 999 { 1000 int rc; 1001 1002 rc = smp_rescan_cpus(); 1003 return rc ? rc : count; 1004 } 1005 static SYSDEV_CLASS_ATTR(rescan, 0200, NULL, rescan_store); 1006 #endif /* CONFIG_HOTPLUG_CPU */ 1007 1008 static ssize_t dispatching_show(struct sysdev_class *class, char *buf) 1009 { 1010 ssize_t count; 1011 1012 mutex_lock(&smp_cpu_state_mutex); 1013 count = sprintf(buf, "%d\n", cpu_management); 1014 mutex_unlock(&smp_cpu_state_mutex); 1015 return count; 1016 } 1017 1018 static ssize_t dispatching_store(struct sysdev_class *dev, const char *buf, 1019 size_t count) 1020 { 1021 int val, rc; 1022 char delim; 1023 1024 if (sscanf(buf, "%d %c", &val, &delim) != 1) 1025 return -EINVAL; 1026 if (val != 0 && val != 1) 1027 return -EINVAL; 1028 rc = 0; 1029 get_online_cpus(); 1030 mutex_lock(&smp_cpu_state_mutex); 1031 if (cpu_management == val) 1032 goto out; 1033 rc = topology_set_cpu_management(val); 1034 if (!rc) 1035 cpu_management = val; 1036 out: 1037 mutex_unlock(&smp_cpu_state_mutex); 1038 put_online_cpus(); 1039 return rc ? rc : count; 1040 } 1041 static SYSDEV_CLASS_ATTR(dispatching, 0644, dispatching_show, 1042 dispatching_store); 1043 1044 /* 1045 * If the resume kernel runs on another cpu than the suspended kernel, 1046 * we have to switch the cpu IDs in the logical map. 1047 */ 1048 void smp_switch_boot_cpu_in_resume(u32 resume_phys_cpu_id, 1049 struct _lowcore *suspend_lowcore) 1050 { 1051 int cpu, suspend_cpu_id, resume_cpu_id; 1052 u32 suspend_phys_cpu_id; 1053 1054 suspend_phys_cpu_id = __cpu_logical_map[suspend_lowcore->cpu_nr]; 1055 suspend_cpu_id = suspend_lowcore->cpu_nr; 1056 1057 for_each_present_cpu(cpu) { 1058 if (__cpu_logical_map[cpu] == resume_phys_cpu_id) { 1059 resume_cpu_id = cpu; 1060 goto found; 1061 } 1062 } 1063 panic("Could not find resume cpu in logical map.\n"); 1064 1065 found: 1066 printk("Resume cpu ID: %i/%i\n", resume_phys_cpu_id, resume_cpu_id); 1067 printk("Suspend cpu ID: %i/%i\n", suspend_phys_cpu_id, suspend_cpu_id); 1068 1069 __cpu_logical_map[resume_cpu_id] = suspend_phys_cpu_id; 1070 __cpu_logical_map[suspend_cpu_id] = resume_phys_cpu_id; 1071 1072 lowcore_ptr[suspend_cpu_id]->cpu_addr = resume_phys_cpu_id; 1073 } 1074 1075 u32 smp_get_phys_cpu_id(void) 1076 { 1077 return __cpu_logical_map[smp_processor_id()]; 1078 } 1079 1080 static int __init topology_init(void) 1081 { 1082 int cpu; 1083 int rc; 1084 1085 register_cpu_notifier(&smp_cpu_nb); 1086 1087 #ifdef CONFIG_HOTPLUG_CPU 1088 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_rescan); 1089 if (rc) 1090 return rc; 1091 #endif 1092 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_dispatching); 1093 if (rc) 1094 return rc; 1095 for_each_present_cpu(cpu) { 1096 rc = smp_add_present_cpu(cpu); 1097 if (rc) 1098 return rc; 1099 } 1100 return 0; 1101 } 1102 subsys_initcall(topology_init); 1103