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processor_perflib.c
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linux-6.19.14/drivers/acpi/processor_perflib.c
1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $) 4 * 5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 7 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> 8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 9 * - Added processor hotplug support 10 */ 11 12#define pr_fmt(fmt) "ACPI: " fmt 13 14#include <linux/kernel.h> 15#include <linux/module.h> 16#include <linux/init.h> 17#include <linux/cpufreq.h> 18#include <linux/slab.h> 19#include <linux/acpi.h> 20#include <acpi/processor.h> 21#ifdef CONFIG_X86 22#include <asm/cpufeature.h> 23#include <asm/msr.h> 24#endif 25 26#define ACPI_PROCESSOR_FILE_PERFORMANCE "performance" 27 28/* 29 * _PPC support is implemented as a CPUfreq policy notifier: 30 * This means each time a CPUfreq driver registered also with 31 * the ACPI core is asked to change the speed policy, the maximum 32 * value is adjusted so that it is within the platform limit. 33 * 34 * Also, when a new platform limit value is detected, the CPUfreq 35 * policy is adjusted accordingly. 36 */ 37 38/* ignore_ppc: 39 * -1 -> cpufreq low level drivers not initialized -> _PSS, etc. not called yet 40 * ignore _PPC 41 * 0 -> cpufreq low level drivers initialized -> consider _PPC values 42 * 1 -> ignore _PPC totally -> forced by user through boot param 43 */ 44static int ignore_ppc = -1; 45module_param(ignore_ppc, int, 0644); 46MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \ 47 "limited by BIOS, this should help"); 48 49static bool acpi_processor_ppc_in_use; 50 51static int acpi_processor_get_platform_limit(struct acpi_processor *pr) 52{ 53 acpi_status status = 0; 54 unsigned long long ppc = 0; 55 s32 qos_value; 56 int index; 57 int ret; 58 59 if (!pr) 60 return -EINVAL; 61 62 /* 63 * _PPC indicates the maximum state currently supported by the platform 64 * (e.g. 0 = states 0..n; 1 = states 1..n; etc. 65 */ 66 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc); 67 if (status != AE_NOT_FOUND) { 68 acpi_processor_ppc_in_use = true; 69 70 if (ACPI_FAILURE(status)) { 71 acpi_evaluation_failure_warn(pr->handle, "_PPC", status); 72 return -ENODEV; 73 } 74 } 75 76 index = ppc; 77 78 if (pr->performance_platform_limit == index || 79 ppc >= pr->performance->state_count) 80 return 0; 81 82 pr_debug("CPU %d: _PPC is %d - frequency %s limited\n", pr->id, 83 index, index ? "is" : "is not"); 84 85 pr->performance_platform_limit = index; 86 87 if (unlikely(!freq_qos_request_active(&pr->perflib_req))) 88 return 0; 89 90 /* 91 * If _PPC returns 0, it means that all of the available states can be 92 * used ("no limit"). 93 */ 94 if (index == 0) 95 qos_value = FREQ_QOS_MAX_DEFAULT_VALUE; 96 else 97 qos_value = pr->performance->states[index].core_frequency * 1000; 98 99 ret = freq_qos_update_request(&pr->perflib_req, qos_value); 100 if (ret < 0) { 101 pr_warn("Failed to update perflib freq constraint: CPU%d (%d)\n", 102 pr->id, ret); 103 } 104 105 return 0; 106} 107 108#define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80 109/* 110 * acpi_processor_ppc_ost: Notify firmware the _PPC evaluation status 111 * @handle: ACPI processor handle 112 * @status: the status code of _PPC evaluation 113 * 0: success. OSPM is now using the performance state specified. 114 * 1: failure. OSPM has not changed the number of P-states in use 115 */ 116static void acpi_processor_ppc_ost(acpi_handle handle, int status) 117{ 118 if (acpi_has_method(handle, "_OST")) 119 acpi_evaluate_ost(handle, ACPI_PROCESSOR_NOTIFY_PERFORMANCE, 120 status, NULL); 121} 122 123void acpi_processor_ppc_has_changed(struct acpi_processor *pr, int event_flag) 124{ 125 int ret; 126 127 if (ignore_ppc || !pr->performance) { 128 /* 129 * Only when it is notification event, the _OST object 130 * will be evaluated. Otherwise it is skipped. 131 */ 132 if (event_flag) 133 acpi_processor_ppc_ost(pr->handle, 1); 134 return; 135 } 136 137 ret = acpi_processor_get_platform_limit(pr); 138 /* 139 * Only when it is notification event, the _OST object 140 * will be evaluated. Otherwise it is skipped. 141 */ 142 if (event_flag) { 143 if (ret < 0) 144 acpi_processor_ppc_ost(pr->handle, 1); 145 else 146 acpi_processor_ppc_ost(pr->handle, 0); 147 } 148 if (ret >= 0) 149 cpufreq_update_limits(pr->id); 150} 151 152int acpi_processor_get_bios_limit(int cpu, unsigned int *limit) 153{ 154 struct acpi_processor *pr; 155 156 pr = per_cpu(processors, cpu); 157 if (!pr || !pr->performance || !pr->performance->state_count) 158 return -ENODEV; 159 160 *limit = pr->performance->states[pr->performance_platform_limit]. 161 core_frequency * 1000; 162 return 0; 163} 164EXPORT_SYMBOL(acpi_processor_get_bios_limit); 165 166void acpi_processor_ignore_ppc_init(void) 167{ 168 if (ignore_ppc < 0) 169 ignore_ppc = 0; 170} 171 172void acpi_processor_ppc_init(struct cpufreq_policy *policy) 173{ 174 unsigned int cpu; 175 176 if (ignore_ppc == 1) 177 return; 178 179 for_each_cpu(cpu, policy->related_cpus) { 180 struct acpi_processor *pr = per_cpu(processors, cpu); 181 int ret; 182 183 if (!pr) 184 continue; 185 186 /* 187 * Reset performance_platform_limit in case there is a stale 188 * value in it, so as to make it match the "no limit" QoS value 189 * below. 190 */ 191 pr->performance_platform_limit = 0; 192 193 ret = freq_qos_add_request(&policy->constraints, 194 &pr->perflib_req, FREQ_QOS_MAX, 195 FREQ_QOS_MAX_DEFAULT_VALUE); 196 if (ret < 0) 197 pr_err("Failed to add freq constraint for CPU%d (%d)\n", 198 cpu, ret); 199 200 if (!pr->performance) 201 continue; 202 203 ret = acpi_processor_get_platform_limit(pr); 204 if (ret) 205 pr_err("Failed to update freq constraint for CPU%d (%d)\n", 206 cpu, ret); 207 } 208} 209 210void acpi_processor_ppc_exit(struct cpufreq_policy *policy) 211{ 212 unsigned int cpu; 213 214 for_each_cpu(cpu, policy->related_cpus) { 215 struct acpi_processor *pr = per_cpu(processors, cpu); 216 217 if (pr) 218 freq_qos_remove_request(&pr->perflib_req); 219 } 220} 221 222#ifdef CONFIG_X86 223 224static DEFINE_MUTEX(performance_mutex); 225 226static int acpi_processor_get_performance_control(struct acpi_processor *pr) 227{ 228 int result = 0; 229 acpi_status status = 0; 230 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 231 union acpi_object *pct = NULL; 232 union acpi_object obj = { 0 }; 233 234 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer); 235 if (ACPI_FAILURE(status)) { 236 acpi_evaluation_failure_warn(pr->handle, "_PCT", status); 237 return -ENODEV; 238 } 239 240 pct = (union acpi_object *)buffer.pointer; 241 if (!pct || pct->type != ACPI_TYPE_PACKAGE || pct->package.count != 2) { 242 pr_err("Invalid _PCT data\n"); 243 result = -EFAULT; 244 goto end; 245 } 246 247 /* 248 * control_register 249 */ 250 251 obj = pct->package.elements[0]; 252 253 if (!obj.buffer.pointer || obj.type != ACPI_TYPE_BUFFER || 254 obj.buffer.length < sizeof(struct acpi_pct_register)) { 255 pr_err("Invalid _PCT data (control_register)\n"); 256 result = -EFAULT; 257 goto end; 258 } 259 memcpy(&pr->performance->control_register, obj.buffer.pointer, 260 sizeof(struct acpi_pct_register)); 261 262 /* 263 * status_register 264 */ 265 266 obj = pct->package.elements[1]; 267 268 if (!obj.buffer.pointer || obj.type != ACPI_TYPE_BUFFER || 269 obj.buffer.length < sizeof(struct acpi_pct_register)) { 270 pr_err("Invalid _PCT data (status_register)\n"); 271 result = -EFAULT; 272 goto end; 273 } 274 275 memcpy(&pr->performance->status_register, obj.buffer.pointer, 276 sizeof(struct acpi_pct_register)); 277 278end: 279 kfree(buffer.pointer); 280 281 return result; 282} 283 284/* 285 * Some AMDs have 50MHz frequency multiples, but only provide 100MHz rounding 286 * in their ACPI data. Calculate the real values and fix up the _PSS data. 287 */ 288static void amd_fixup_frequency(struct acpi_processor_px *px, int i) 289{ 290 u32 hi, lo, fid, did; 291 int index = px->control & 0x00000007; 292 293 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) 294 return; 295 296 if ((boot_cpu_data.x86 == 0x10 && boot_cpu_data.x86_model < 10) || 297 boot_cpu_data.x86 == 0x11) { 298 rdmsr(MSR_AMD_PSTATE_DEF_BASE + index, lo, hi); 299 /* 300 * MSR C001_0064+: 301 * Bit 63: PstateEn. Read-write. If set, the P-state is valid. 302 */ 303 if (!(hi & BIT(31))) 304 return; 305 306 fid = lo & 0x3f; 307 did = (lo >> 6) & 7; 308 if (boot_cpu_data.x86 == 0x10) 309 px->core_frequency = (100 * (fid + 0x10)) >> did; 310 else 311 px->core_frequency = (100 * (fid + 8)) >> did; 312 } 313} 314 315static int acpi_processor_get_performance_states(struct acpi_processor *pr) 316{ 317 int result = 0; 318 acpi_status status = AE_OK; 319 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 320 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" }; 321 struct acpi_buffer state = { 0, NULL }; 322 union acpi_object *pss = NULL; 323 int i; 324 int last_invalid = -1; 325 326 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer); 327 if (ACPI_FAILURE(status)) { 328 acpi_evaluation_failure_warn(pr->handle, "_PSS", status); 329 return -ENODEV; 330 } 331 332 pss = buffer.pointer; 333 if (!pss || pss->type != ACPI_TYPE_PACKAGE) { 334 pr_err("Invalid _PSS data\n"); 335 result = -EFAULT; 336 goto end; 337 } 338 339 acpi_handle_debug(pr->handle, "Found %d performance states\n", 340 pss->package.count); 341 342 pr->performance->state_count = pss->package.count; 343 pr->performance->states = 344 kmalloc_array(pss->package.count, 345 sizeof(struct acpi_processor_px), 346 GFP_KERNEL); 347 if (!pr->performance->states) { 348 result = -ENOMEM; 349 goto end; 350 } 351 352 for (i = 0; i < pr->performance->state_count; i++) { 353 354 struct acpi_processor_px *px = &(pr->performance->states[i]); 355 356 state.length = sizeof(struct acpi_processor_px); 357 state.pointer = px; 358 359 acpi_handle_debug(pr->handle, "Extracting state %d\n", i); 360 361 status = acpi_extract_package(&(pss->package.elements[i]), 362 &format, &state); 363 if (ACPI_FAILURE(status)) { 364 acpi_handle_warn(pr->handle, "Invalid _PSS data: %s\n", 365 acpi_format_exception(status)); 366 result = -EFAULT; 367 kfree(pr->performance->states); 368 goto end; 369 } 370 371 amd_fixup_frequency(px, i); 372 373 acpi_handle_debug(pr->handle, 374 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n", 375 i, 376 (u32) px->core_frequency, 377 (u32) px->power, 378 (u32) px->transition_latency, 379 (u32) px->bus_master_latency, 380 (u32) px->control, (u32) px->status); 381 382 /* 383 * Check that ACPI's u64 MHz will be valid as u32 KHz in cpufreq 384 */ 385 if (!px->core_frequency || 386 (u32)(px->core_frequency * 1000) != px->core_frequency * 1000) { 387 pr_err(FW_BUG 388 "Invalid BIOS _PSS frequency found for processor %d: 0x%llx MHz\n", 389 pr->id, px->core_frequency); 390 if (last_invalid == -1) 391 last_invalid = i; 392 } else { 393 if (last_invalid != -1) { 394 /* 395 * Copy this valid entry over last_invalid entry 396 */ 397 memcpy(&(pr->performance->states[last_invalid]), 398 px, sizeof(struct acpi_processor_px)); 399 ++last_invalid; 400 } 401 } 402 } 403 404 if (last_invalid == 0) { 405 pr_err(FW_BUG 406 "No valid BIOS _PSS frequency found for processor %d\n", pr->id); 407 result = -EFAULT; 408 kfree(pr->performance->states); 409 pr->performance->states = NULL; 410 } 411 412 if (last_invalid > 0) 413 pr->performance->state_count = last_invalid; 414 415end: 416 kfree(buffer.pointer); 417 418 return result; 419} 420 421int acpi_processor_get_performance_info(struct acpi_processor *pr) 422{ 423 int result = 0; 424 425 if (!pr || !pr->performance || !pr->handle) 426 return -EINVAL; 427 428 if (!acpi_has_method(pr->handle, "_PCT")) { 429 acpi_handle_debug(pr->handle, 430 "ACPI-based processor performance control unavailable\n"); 431 return -ENODEV; 432 } 433 434 result = acpi_processor_get_performance_control(pr); 435 if (result) 436 goto update_bios; 437 438 result = acpi_processor_get_performance_states(pr); 439 if (result) 440 goto update_bios; 441 442 /* We need to call _PPC once when cpufreq starts */ 443 if (ignore_ppc != 1) 444 result = acpi_processor_get_platform_limit(pr); 445 446 return result; 447 448 /* 449 * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that 450 * the BIOS is older than the CPU and does not know its frequencies 451 */ 452 update_bios: 453 if (acpi_has_method(pr->handle, "_PPC")) { 454 if(boot_cpu_has(X86_FEATURE_EST)) 455 pr_warn(FW_BUG "BIOS needs update for CPU " 456 "frequency support\n"); 457 } 458 return result; 459} 460EXPORT_SYMBOL_GPL(acpi_processor_get_performance_info); 461 462int acpi_processor_pstate_control(void) 463{ 464 acpi_status status; 465 466 if (!acpi_gbl_FADT.smi_command || !acpi_gbl_FADT.pstate_control) 467 return 0; 468 469 pr_debug("Writing pstate_control [0x%x] to smi_command [0x%x]\n", 470 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command); 471 472 status = acpi_os_write_port(acpi_gbl_FADT.smi_command, 473 (u32)acpi_gbl_FADT.pstate_control, 8); 474 if (ACPI_SUCCESS(status)) 475 return 1; 476 477 pr_warn("Failed to write pstate_control [0x%x] to smi_command [0x%x]: %s\n", 478 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command, 479 acpi_format_exception(status)); 480 return -EIO; 481} 482 483int acpi_processor_notify_smm(struct module *calling_module) 484{ 485 static int is_done; 486 int result = 0; 487 488 if (!acpi_processor_cpufreq_init) 489 return -EBUSY; 490 491 if (!try_module_get(calling_module)) 492 return -EINVAL; 493 494 /* 495 * is_done is set to negative if an error occurs and to 1 if no error 496 * occurrs, but SMM has been notified already. This avoids repeated 497 * notification which might lead to unexpected results. 498 */ 499 if (is_done != 0) { 500 if (is_done < 0) 501 result = is_done; 502 503 goto out_put; 504 } 505 506 result = acpi_processor_pstate_control(); 507 if (result <= 0) { 508 if (result) { 509 is_done = result; 510 } else { 511 pr_debug("No SMI port or pstate_control\n"); 512 is_done = 1; 513 } 514 goto out_put; 515 } 516 517 is_done = 1; 518 /* 519 * Success. If there _PPC, unloading the cpufreq driver would be risky, 520 * so disallow it in that case. 521 */ 522 if (acpi_processor_ppc_in_use) 523 return 0; 524 525out_put: 526 module_put(calling_module); 527 return result; 528} 529EXPORT_SYMBOL(acpi_processor_notify_smm); 530 531int acpi_processor_get_psd(acpi_handle handle, struct acpi_psd_package *pdomain) 532{ 533 int result = 0; 534 acpi_status status = AE_OK; 535 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 536 struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"}; 537 struct acpi_buffer state = {0, NULL}; 538 union acpi_object *psd = NULL; 539 540 status = acpi_evaluate_object(handle, "_PSD", NULL, &buffer); 541 if (ACPI_FAILURE(status)) { 542 return -ENODEV; 543 } 544 545 psd = buffer.pointer; 546 if (!psd || psd->type != ACPI_TYPE_PACKAGE) { 547 pr_err("Invalid _PSD data\n"); 548 result = -EFAULT; 549 goto end; 550 } 551 552 if (psd->package.count != 1) { 553 pr_err("Invalid _PSD data\n"); 554 result = -EFAULT; 555 goto end; 556 } 557 558 state.length = sizeof(struct acpi_psd_package); 559 state.pointer = pdomain; 560 561 status = acpi_extract_package(&(psd->package.elements[0]), &format, &state); 562 if (ACPI_FAILURE(status)) { 563 pr_err("Invalid _PSD data\n"); 564 result = -EFAULT; 565 goto end; 566 } 567 568 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) { 569 pr_err("Unknown _PSD:num_entries\n"); 570 result = -EFAULT; 571 goto end; 572 } 573 574 if (pdomain->revision != ACPI_PSD_REV0_REVISION) { 575 pr_err("Unknown _PSD:revision\n"); 576 result = -EFAULT; 577 goto end; 578 } 579 580 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && 581 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && 582 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { 583 pr_err("Invalid _PSD:coord_type\n"); 584 result = -EFAULT; 585 goto end; 586 } 587end: 588 kfree(buffer.pointer); 589 return result; 590} 591EXPORT_SYMBOL(acpi_processor_get_psd); 592 593int acpi_processor_preregister_performance( 594 struct acpi_processor_performance __percpu *performance) 595{ 596 int count_target; 597 int retval = 0; 598 unsigned int i, j; 599 cpumask_var_t covered_cpus; 600 struct acpi_processor *pr; 601 struct acpi_psd_package *pdomain; 602 struct acpi_processor *match_pr; 603 struct acpi_psd_package *match_pdomain; 604 605 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) 606 return -ENOMEM; 607 608 mutex_lock(&performance_mutex); 609 610 /* 611 * Check if another driver has already registered, and abort before 612 * changing pr->performance if it has. Check input data as well. 613 */ 614 for_each_possible_cpu(i) { 615 pr = per_cpu(processors, i); 616 if (!pr) { 617 /* Look only at processors in ACPI namespace */ 618 continue; 619 } 620 621 if (pr->performance) { 622 retval = -EBUSY; 623 goto err_out; 624 } 625 626 if (!performance || !per_cpu_ptr(performance, i)) { 627 retval = -EINVAL; 628 goto err_out; 629 } 630 } 631 632 /* Call _PSD for all CPUs */ 633 for_each_possible_cpu(i) { 634 pr = per_cpu(processors, i); 635 if (!pr) 636 continue; 637 638 pr->performance = per_cpu_ptr(performance, i); 639 pdomain = &(pr->performance->domain_info); 640 if (acpi_processor_get_psd(pr->handle, pdomain)) { 641 retval = -EINVAL; 642 continue; 643 } 644 } 645 if (retval) 646 goto err_ret; 647 648 /* 649 * Now that we have _PSD data from all CPUs, lets setup P-state 650 * domain info. 651 */ 652 for_each_possible_cpu(i) { 653 pr = per_cpu(processors, i); 654 if (!pr) 655 continue; 656 657 if (cpumask_test_cpu(i, covered_cpus)) 658 continue; 659 660 pdomain = &(pr->performance->domain_info); 661 cpumask_set_cpu(i, pr->performance->shared_cpu_map); 662 cpumask_set_cpu(i, covered_cpus); 663 if (pdomain->num_processors <= 1) 664 continue; 665 666 /* Validate the Domain info */ 667 count_target = pdomain->num_processors; 668 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL) 669 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL; 670 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL) 671 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW; 672 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY) 673 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY; 674 675 for_each_possible_cpu(j) { 676 if (i == j) 677 continue; 678 679 match_pr = per_cpu(processors, j); 680 if (!match_pr) 681 continue; 682 683 match_pdomain = &(match_pr->performance->domain_info); 684 if (match_pdomain->domain != pdomain->domain) 685 continue; 686 687 /* Here i and j are in the same domain */ 688 689 if (match_pdomain->num_processors != count_target) { 690 retval = -EINVAL; 691 goto err_ret; 692 } 693 694 if (pdomain->coord_type != match_pdomain->coord_type) { 695 retval = -EINVAL; 696 goto err_ret; 697 } 698 699 cpumask_set_cpu(j, covered_cpus); 700 cpumask_set_cpu(j, pr->performance->shared_cpu_map); 701 } 702 703 for_each_possible_cpu(j) { 704 if (i == j) 705 continue; 706 707 match_pr = per_cpu(processors, j); 708 if (!match_pr) 709 continue; 710 711 match_pdomain = &(match_pr->performance->domain_info); 712 if (match_pdomain->domain != pdomain->domain) 713 continue; 714 715 match_pr->performance->shared_type = 716 pr->performance->shared_type; 717 cpumask_copy(match_pr->performance->shared_cpu_map, 718 pr->performance->shared_cpu_map); 719 } 720 } 721 722err_ret: 723 for_each_possible_cpu(i) { 724 pr = per_cpu(processors, i); 725 if (!pr || !pr->performance) 726 continue; 727 728 /* Assume no coordination on any error parsing domain info */ 729 if (retval) { 730 cpumask_clear(pr->performance->shared_cpu_map); 731 cpumask_set_cpu(i, pr->performance->shared_cpu_map); 732 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_NONE; 733 } 734 pr->performance = NULL; /* Will be set for real in register */ 735 } 736 737err_out: 738 mutex_unlock(&performance_mutex); 739 free_cpumask_var(covered_cpus); 740 return retval; 741} 742EXPORT_SYMBOL(acpi_processor_preregister_performance); 743 744int acpi_processor_register_performance(struct acpi_processor_performance 745 *performance, unsigned int cpu) 746{ 747 struct acpi_processor *pr; 748 749 if (!acpi_processor_cpufreq_init) 750 return -EINVAL; 751 752 mutex_lock(&performance_mutex); 753 754 pr = per_cpu(processors, cpu); 755 if (!pr) { 756 mutex_unlock(&performance_mutex); 757 return -ENODEV; 758 } 759 760 if (pr->performance) { 761 mutex_unlock(&performance_mutex); 762 return -EBUSY; 763 } 764 765 WARN_ON(!performance); 766 767 pr->performance = performance; 768 769 if (acpi_processor_get_performance_info(pr)) { 770 pr->performance = NULL; 771 mutex_unlock(&performance_mutex); 772 return -EIO; 773 } 774 775 mutex_unlock(&performance_mutex); 776 return 0; 777} 778EXPORT_SYMBOL(acpi_processor_register_performance); 779 780void acpi_processor_unregister_performance(unsigned int cpu) 781{ 782 struct acpi_processor *pr; 783 784 mutex_lock(&performance_mutex); 785 786 pr = per_cpu(processors, cpu); 787 if (!pr) 788 goto unlock; 789 790 if (pr->performance) 791 kfree(pr->performance->states); 792 793 pr->performance = NULL; 794 795unlock: 796 mutex_unlock(&performance_mutex); 797} 798EXPORT_SYMBOL(acpi_processor_unregister_performance); 799#endif
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