1 /* 2 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $) 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> 7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 8 * - Added processor hotplug support 9 * 10 * 11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or (at 16 * your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, but 19 * WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 * General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License along 24 * with this program; if not, write to the Free Software Foundation, Inc., 25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 26 * 27 */ 28 29 #include <linux/kernel.h> 30 #include <linux/module.h> 31 #include <linux/init.h> 32 #include <linux/cpufreq.h> 33 34 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF 35 #include <linux/proc_fs.h> 36 #include <linux/seq_file.h> 37 #include <linux/mutex.h> 38 39 #include <asm/uaccess.h> 40 #endif 41 42 #include <acpi/acpi_bus.h> 43 #include <acpi/processor.h> 44 45 #define ACPI_PROCESSOR_COMPONENT 0x01000000 46 #define ACPI_PROCESSOR_CLASS "processor" 47 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance" 48 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 49 ACPI_MODULE_NAME("processor_perflib"); 50 51 static DEFINE_MUTEX(performance_mutex); 52 53 /* 54 * _PPC support is implemented as a CPUfreq policy notifier: 55 * This means each time a CPUfreq driver registered also with 56 * the ACPI core is asked to change the speed policy, the maximum 57 * value is adjusted so that it is within the platform limit. 58 * 59 * Also, when a new platform limit value is detected, the CPUfreq 60 * policy is adjusted accordingly. 61 */ 62 63 #define PPC_REGISTERED 1 64 #define PPC_IN_USE 2 65 66 static int acpi_processor_ppc_status = 0; 67 68 static int acpi_processor_ppc_notifier(struct notifier_block *nb, 69 unsigned long event, void *data) 70 { 71 struct cpufreq_policy *policy = data; 72 struct acpi_processor *pr; 73 unsigned int ppc = 0; 74 75 mutex_lock(&performance_mutex); 76 77 if (event != CPUFREQ_INCOMPATIBLE) 78 goto out; 79 80 pr = processors[policy->cpu]; 81 if (!pr || !pr->performance) 82 goto out; 83 84 ppc = (unsigned int)pr->performance_platform_limit; 85 86 if (ppc >= pr->performance->state_count) 87 goto out; 88 89 cpufreq_verify_within_limits(policy, 0, 90 pr->performance->states[ppc]. 91 core_frequency * 1000); 92 93 out: 94 mutex_unlock(&performance_mutex); 95 96 return 0; 97 } 98 99 static struct notifier_block acpi_ppc_notifier_block = { 100 .notifier_call = acpi_processor_ppc_notifier, 101 }; 102 103 static int acpi_processor_get_platform_limit(struct acpi_processor *pr) 104 { 105 acpi_status status = 0; 106 unsigned long ppc = 0; 107 108 109 if (!pr) 110 return -EINVAL; 111 112 /* 113 * _PPC indicates the maximum state currently supported by the platform 114 * (e.g. 0 = states 0..n; 1 = states 1..n; etc. 115 */ 116 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc); 117 118 if (status != AE_NOT_FOUND) 119 acpi_processor_ppc_status |= PPC_IN_USE; 120 121 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { 122 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC")); 123 return -ENODEV; 124 } 125 126 pr->performance_platform_limit = (int)ppc; 127 128 return 0; 129 } 130 131 int acpi_processor_ppc_has_changed(struct acpi_processor *pr) 132 { 133 int ret = acpi_processor_get_platform_limit(pr); 134 if (ret < 0) 135 return (ret); 136 else 137 return cpufreq_update_policy(pr->id); 138 } 139 140 void acpi_processor_ppc_init(void) 141 { 142 if (!cpufreq_register_notifier 143 (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER)) 144 acpi_processor_ppc_status |= PPC_REGISTERED; 145 else 146 printk(KERN_DEBUG 147 "Warning: Processor Platform Limit not supported.\n"); 148 } 149 150 void acpi_processor_ppc_exit(void) 151 { 152 if (acpi_processor_ppc_status & PPC_REGISTERED) 153 cpufreq_unregister_notifier(&acpi_ppc_notifier_block, 154 CPUFREQ_POLICY_NOTIFIER); 155 156 acpi_processor_ppc_status &= ~PPC_REGISTERED; 157 } 158 159 static int acpi_processor_get_performance_control(struct acpi_processor *pr) 160 { 161 int result = 0; 162 acpi_status status = 0; 163 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 164 union acpi_object *pct = NULL; 165 union acpi_object obj = { 0 }; 166 167 168 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer); 169 if (ACPI_FAILURE(status)) { 170 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT")); 171 return -ENODEV; 172 } 173 174 pct = (union acpi_object *)buffer.pointer; 175 if (!pct || (pct->type != ACPI_TYPE_PACKAGE) 176 || (pct->package.count != 2)) { 177 printk(KERN_ERR PREFIX "Invalid _PCT data\n"); 178 result = -EFAULT; 179 goto end; 180 } 181 182 /* 183 * control_register 184 */ 185 186 obj = pct->package.elements[0]; 187 188 if ((obj.type != ACPI_TYPE_BUFFER) 189 || (obj.buffer.length < sizeof(struct acpi_pct_register)) 190 || (obj.buffer.pointer == NULL)) { 191 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n"); 192 result = -EFAULT; 193 goto end; 194 } 195 memcpy(&pr->performance->control_register, obj.buffer.pointer, 196 sizeof(struct acpi_pct_register)); 197 198 /* 199 * status_register 200 */ 201 202 obj = pct->package.elements[1]; 203 204 if ((obj.type != ACPI_TYPE_BUFFER) 205 || (obj.buffer.length < sizeof(struct acpi_pct_register)) 206 || (obj.buffer.pointer == NULL)) { 207 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n"); 208 result = -EFAULT; 209 goto end; 210 } 211 212 memcpy(&pr->performance->status_register, obj.buffer.pointer, 213 sizeof(struct acpi_pct_register)); 214 215 end: 216 kfree(buffer.pointer); 217 218 return result; 219 } 220 221 static int acpi_processor_get_performance_states(struct acpi_processor *pr) 222 { 223 int result = 0; 224 acpi_status status = AE_OK; 225 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 226 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" }; 227 struct acpi_buffer state = { 0, NULL }; 228 union acpi_object *pss = NULL; 229 int i; 230 231 232 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer); 233 if (ACPI_FAILURE(status)) { 234 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS")); 235 return -ENODEV; 236 } 237 238 pss = buffer.pointer; 239 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) { 240 printk(KERN_ERR PREFIX "Invalid _PSS data\n"); 241 result = -EFAULT; 242 goto end; 243 } 244 245 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n", 246 pss->package.count)); 247 248 pr->performance->state_count = pss->package.count; 249 pr->performance->states = 250 kmalloc(sizeof(struct acpi_processor_px) * pss->package.count, 251 GFP_KERNEL); 252 if (!pr->performance->states) { 253 result = -ENOMEM; 254 goto end; 255 } 256 257 for (i = 0; i < pr->performance->state_count; i++) { 258 259 struct acpi_processor_px *px = &(pr->performance->states[i]); 260 261 state.length = sizeof(struct acpi_processor_px); 262 state.pointer = px; 263 264 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i)); 265 266 status = acpi_extract_package(&(pss->package.elements[i]), 267 &format, &state); 268 if (ACPI_FAILURE(status)) { 269 ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data")); 270 result = -EFAULT; 271 kfree(pr->performance->states); 272 goto end; 273 } 274 275 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 276 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n", 277 i, 278 (u32) px->core_frequency, 279 (u32) px->power, 280 (u32) px->transition_latency, 281 (u32) px->bus_master_latency, 282 (u32) px->control, (u32) px->status)); 283 284 if (!px->core_frequency) { 285 printk(KERN_ERR PREFIX 286 "Invalid _PSS data: freq is zero\n"); 287 result = -EFAULT; 288 kfree(pr->performance->states); 289 goto end; 290 } 291 } 292 293 end: 294 kfree(buffer.pointer); 295 296 return result; 297 } 298 299 static int acpi_processor_get_performance_info(struct acpi_processor *pr) 300 { 301 int result = 0; 302 acpi_status status = AE_OK; 303 acpi_handle handle = NULL; 304 305 306 if (!pr || !pr->performance || !pr->handle) 307 return -EINVAL; 308 309 status = acpi_get_handle(pr->handle, "_PCT", &handle); 310 if (ACPI_FAILURE(status)) { 311 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 312 "ACPI-based processor performance control unavailable\n")); 313 return -ENODEV; 314 } 315 316 result = acpi_processor_get_performance_control(pr); 317 if (result) 318 return result; 319 320 result = acpi_processor_get_performance_states(pr); 321 if (result) 322 return result; 323 324 return 0; 325 } 326 327 int acpi_processor_notify_smm(struct module *calling_module) 328 { 329 acpi_status status; 330 static int is_done = 0; 331 332 333 if (!(acpi_processor_ppc_status & PPC_REGISTERED)) 334 return -EBUSY; 335 336 if (!try_module_get(calling_module)) 337 return -EINVAL; 338 339 /* is_done is set to negative if an error occured, 340 * and to postitive if _no_ error occured, but SMM 341 * was already notified. This avoids double notification 342 * which might lead to unexpected results... 343 */ 344 if (is_done > 0) { 345 module_put(calling_module); 346 return 0; 347 } else if (is_done < 0) { 348 module_put(calling_module); 349 return is_done; 350 } 351 352 is_done = -EIO; 353 354 /* Can't write pstate_control to smi_command if either value is zero */ 355 if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) { 356 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n")); 357 module_put(calling_module); 358 return 0; 359 } 360 361 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 362 "Writing pstate_control [0x%x] to smi_command [0x%x]\n", 363 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command)); 364 365 status = acpi_os_write_port(acpi_gbl_FADT.smi_command, 366 (u32) acpi_gbl_FADT.pstate_control, 8); 367 if (ACPI_FAILURE(status)) { 368 ACPI_EXCEPTION((AE_INFO, status, 369 "Failed to write pstate_control [0x%x] to " 370 "smi_command [0x%x]", acpi_gbl_FADT.pstate_control, 371 acpi_gbl_FADT.smi_command)); 372 module_put(calling_module); 373 return status; 374 } 375 376 /* Success. If there's no _PPC, we need to fear nothing, so 377 * we can allow the cpufreq driver to be rmmod'ed. */ 378 is_done = 1; 379 380 if (!(acpi_processor_ppc_status & PPC_IN_USE)) 381 module_put(calling_module); 382 383 return 0; 384 } 385 386 EXPORT_SYMBOL(acpi_processor_notify_smm); 387 388 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF 389 /* /proc/acpi/processor/../performance interface (DEPRECATED) */ 390 391 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file); 392 static struct file_operations acpi_processor_perf_fops = { 393 .open = acpi_processor_perf_open_fs, 394 .read = seq_read, 395 .llseek = seq_lseek, 396 .release = single_release, 397 }; 398 399 static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset) 400 { 401 struct acpi_processor *pr = seq->private; 402 int i; 403 404 405 if (!pr) 406 goto end; 407 408 if (!pr->performance) { 409 seq_puts(seq, "<not supported>\n"); 410 goto end; 411 } 412 413 seq_printf(seq, "state count: %d\n" 414 "active state: P%d\n", 415 pr->performance->state_count, pr->performance->state); 416 417 seq_puts(seq, "states:\n"); 418 for (i = 0; i < pr->performance->state_count; i++) 419 seq_printf(seq, 420 " %cP%d: %d MHz, %d mW, %d uS\n", 421 (i == pr->performance->state ? '*' : ' '), i, 422 (u32) pr->performance->states[i].core_frequency, 423 (u32) pr->performance->states[i].power, 424 (u32) pr->performance->states[i].transition_latency); 425 426 end: 427 return 0; 428 } 429 430 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file) 431 { 432 return single_open(file, acpi_processor_perf_seq_show, 433 PDE(inode)->data); 434 } 435 436 static void acpi_cpufreq_add_file(struct acpi_processor *pr) 437 { 438 struct proc_dir_entry *entry = NULL; 439 struct acpi_device *device = NULL; 440 441 442 if (acpi_bus_get_device(pr->handle, &device)) 443 return; 444 445 /* add file 'performance' [R/W] */ 446 entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE, 447 S_IFREG | S_IRUGO, 448 acpi_device_dir(device)); 449 if (entry){ 450 entry->proc_fops = &acpi_processor_perf_fops; 451 entry->data = acpi_driver_data(device); 452 entry->owner = THIS_MODULE; 453 } 454 return; 455 } 456 457 static void acpi_cpufreq_remove_file(struct acpi_processor *pr) 458 { 459 struct acpi_device *device = NULL; 460 461 462 if (acpi_bus_get_device(pr->handle, &device)) 463 return; 464 465 /* remove file 'performance' */ 466 remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE, 467 acpi_device_dir(device)); 468 469 return; 470 } 471 472 #else 473 static void acpi_cpufreq_add_file(struct acpi_processor *pr) 474 { 475 return; 476 } 477 static void acpi_cpufreq_remove_file(struct acpi_processor *pr) 478 { 479 return; 480 } 481 #endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */ 482 483 static int acpi_processor_get_psd(struct acpi_processor *pr) 484 { 485 int result = 0; 486 acpi_status status = AE_OK; 487 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 488 struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"}; 489 struct acpi_buffer state = {0, NULL}; 490 union acpi_object *psd = NULL; 491 struct acpi_psd_package *pdomain; 492 493 status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer); 494 if (ACPI_FAILURE(status)) { 495 return -ENODEV; 496 } 497 498 psd = buffer.pointer; 499 if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) { 500 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n")); 501 result = -EFAULT; 502 goto end; 503 } 504 505 if (psd->package.count != 1) { 506 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n")); 507 result = -EFAULT; 508 goto end; 509 } 510 511 pdomain = &(pr->performance->domain_info); 512 513 state.length = sizeof(struct acpi_psd_package); 514 state.pointer = pdomain; 515 516 status = acpi_extract_package(&(psd->package.elements[0]), 517 &format, &state); 518 if (ACPI_FAILURE(status)) { 519 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n")); 520 result = -EFAULT; 521 goto end; 522 } 523 524 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) { 525 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:num_entries\n")); 526 result = -EFAULT; 527 goto end; 528 } 529 530 if (pdomain->revision != ACPI_PSD_REV0_REVISION) { 531 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:revision\n")); 532 result = -EFAULT; 533 goto end; 534 } 535 536 end: 537 kfree(buffer.pointer); 538 return result; 539 } 540 541 int acpi_processor_preregister_performance( 542 struct acpi_processor_performance **performance) 543 { 544 int count, count_target; 545 int retval = 0; 546 unsigned int i, j; 547 cpumask_t covered_cpus; 548 struct acpi_processor *pr; 549 struct acpi_psd_package *pdomain; 550 struct acpi_processor *match_pr; 551 struct acpi_psd_package *match_pdomain; 552 553 mutex_lock(&performance_mutex); 554 555 retval = 0; 556 557 /* Call _PSD for all CPUs */ 558 for_each_possible_cpu(i) { 559 pr = processors[i]; 560 if (!pr) { 561 /* Look only at processors in ACPI namespace */ 562 continue; 563 } 564 565 if (pr->performance) { 566 retval = -EBUSY; 567 continue; 568 } 569 570 if (!performance || !performance[i]) { 571 retval = -EINVAL; 572 continue; 573 } 574 575 pr->performance = performance[i]; 576 cpu_set(i, pr->performance->shared_cpu_map); 577 if (acpi_processor_get_psd(pr)) { 578 retval = -EINVAL; 579 continue; 580 } 581 } 582 if (retval) 583 goto err_ret; 584 585 /* 586 * Now that we have _PSD data from all CPUs, lets setup P-state 587 * domain info. 588 */ 589 for_each_possible_cpu(i) { 590 pr = processors[i]; 591 if (!pr) 592 continue; 593 594 /* Basic validity check for domain info */ 595 pdomain = &(pr->performance->domain_info); 596 if ((pdomain->revision != ACPI_PSD_REV0_REVISION) || 597 (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES)) { 598 retval = -EINVAL; 599 goto err_ret; 600 } 601 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && 602 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && 603 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { 604 retval = -EINVAL; 605 goto err_ret; 606 } 607 } 608 609 cpus_clear(covered_cpus); 610 for_each_possible_cpu(i) { 611 pr = processors[i]; 612 if (!pr) 613 continue; 614 615 if (cpu_isset(i, covered_cpus)) 616 continue; 617 618 pdomain = &(pr->performance->domain_info); 619 cpu_set(i, pr->performance->shared_cpu_map); 620 cpu_set(i, covered_cpus); 621 if (pdomain->num_processors <= 1) 622 continue; 623 624 /* Validate the Domain info */ 625 count_target = pdomain->num_processors; 626 count = 1; 627 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL) 628 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL; 629 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL) 630 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW; 631 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY) 632 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY; 633 634 for_each_possible_cpu(j) { 635 if (i == j) 636 continue; 637 638 match_pr = processors[j]; 639 if (!match_pr) 640 continue; 641 642 match_pdomain = &(match_pr->performance->domain_info); 643 if (match_pdomain->domain != pdomain->domain) 644 continue; 645 646 /* Here i and j are in the same domain */ 647 648 if (match_pdomain->num_processors != count_target) { 649 retval = -EINVAL; 650 goto err_ret; 651 } 652 653 if (pdomain->coord_type != match_pdomain->coord_type) { 654 retval = -EINVAL; 655 goto err_ret; 656 } 657 658 cpu_set(j, covered_cpus); 659 cpu_set(j, pr->performance->shared_cpu_map); 660 count++; 661 } 662 663 for_each_possible_cpu(j) { 664 if (i == j) 665 continue; 666 667 match_pr = processors[j]; 668 if (!match_pr) 669 continue; 670 671 match_pdomain = &(match_pr->performance->domain_info); 672 if (match_pdomain->domain != pdomain->domain) 673 continue; 674 675 match_pr->performance->shared_type = 676 pr->performance->shared_type; 677 match_pr->performance->shared_cpu_map = 678 pr->performance->shared_cpu_map; 679 } 680 } 681 682 err_ret: 683 for_each_possible_cpu(i) { 684 pr = processors[i]; 685 if (!pr || !pr->performance) 686 continue; 687 688 /* Assume no coordination on any error parsing domain info */ 689 if (retval) { 690 cpus_clear(pr->performance->shared_cpu_map); 691 cpu_set(i, pr->performance->shared_cpu_map); 692 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL; 693 } 694 pr->performance = NULL; /* Will be set for real in register */ 695 } 696 697 mutex_unlock(&performance_mutex); 698 return retval; 699 } 700 EXPORT_SYMBOL(acpi_processor_preregister_performance); 701 702 703 int 704 acpi_processor_register_performance(struct acpi_processor_performance 705 *performance, unsigned int cpu) 706 { 707 struct acpi_processor *pr; 708 709 710 if (!(acpi_processor_ppc_status & PPC_REGISTERED)) 711 return -EINVAL; 712 713 mutex_lock(&performance_mutex); 714 715 pr = processors[cpu]; 716 if (!pr) { 717 mutex_unlock(&performance_mutex); 718 return -ENODEV; 719 } 720 721 if (pr->performance) { 722 mutex_unlock(&performance_mutex); 723 return -EBUSY; 724 } 725 726 WARN_ON(!performance); 727 728 pr->performance = performance; 729 730 if (acpi_processor_get_performance_info(pr)) { 731 pr->performance = NULL; 732 mutex_unlock(&performance_mutex); 733 return -EIO; 734 } 735 736 acpi_cpufreq_add_file(pr); 737 738 mutex_unlock(&performance_mutex); 739 return 0; 740 } 741 742 EXPORT_SYMBOL(acpi_processor_register_performance); 743 744 void 745 acpi_processor_unregister_performance(struct acpi_processor_performance 746 *performance, unsigned int cpu) 747 { 748 struct acpi_processor *pr; 749 750 751 mutex_lock(&performance_mutex); 752 753 pr = processors[cpu]; 754 if (!pr) { 755 mutex_unlock(&performance_mutex); 756 return; 757 } 758 759 if (pr->performance) 760 kfree(pr->performance->states); 761 pr->performance = NULL; 762 763 acpi_cpufreq_remove_file(pr); 764 765 mutex_unlock(&performance_mutex); 766 767 return; 768 } 769 770 EXPORT_SYMBOL(acpi_processor_unregister_performance); 771