drivers/acpi/acpica/utdelete.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /*******************************************************************************
   3  *
   4  * Module Name: utdelete - object deletion and reference count utilities
   5  *
   6  ******************************************************************************/
   7
   8 #include <acpi/acpi.h>
   9 #include "accommon.h"
  10 #include "acinterp.h"
  11 #include "acnamesp.h"
  12 #include "acevents.h"
  13
  14 #define _COMPONENT          ACPI_UTILITIES
  15 ACPI_MODULE_NAME("utdelete")
  16
  17 /* Local prototypes */
  18 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object);
  19
  20 static void
  21 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action);
  22
  23 /*******************************************************************************
  24  *
  25  * FUNCTION:    acpi_ut_delete_internal_obj
  26  *
  27  * PARAMETERS:  object         - Object to be deleted
  28  *
  29  * RETURN:      None
  30  *
  31  * DESCRIPTION: Low level object deletion, after reference counts have been
  32  *              updated (All reference counts, including sub-objects!)
  33  *
  34  ******************************************************************************/
  35
  36 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
  37 {
  38         void *obj_pointer = NULL;
  39         union acpi_operand_object *handler_desc;
  40         union acpi_operand_object *second_desc;
  41         union acpi_operand_object *next_desc;
  42         union acpi_operand_object *start_desc;
  43         union acpi_operand_object **last_obj_ptr;
  44
  45         ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object);
  46
  47         if (!object) {
  48                 return_VOID;
  49         }
  50
  51         /*
  52          * Must delete or free any pointers within the object that are not
  53          * actual ACPI objects (for example, a raw buffer pointer).
  54          */
  55         switch (object->common.type) {
  56         case ACPI_TYPE_STRING:
  57
  58                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
  59                                   "**** String %p, ptr %p\n", object,
  60                                   object->string.pointer));
  61
  62                 /* Free the actual string buffer */
  63
  64                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
  65
  66                         /* But only if it is NOT a pointer into an ACPI table */
  67
  68                         obj_pointer = object->string.pointer;
  69                 }
  70                 break;
  71
  72         case ACPI_TYPE_BUFFER:
  73
  74                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
  75                                   "**** Buffer %p, ptr %p\n", object,
  76                                   object->buffer.pointer));
  77
  78                 /* Free the actual buffer */
  79
  80                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
  81
  82                         /* But only if it is NOT a pointer into an ACPI table */
  83
  84                         obj_pointer = object->buffer.pointer;
  85                 }
  86                 break;
  87
  88         case ACPI_TYPE_PACKAGE:
  89
  90                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
  91                                   " **** Package of count %X\n",
  92                                   object->package.count));
  93
  94                 /*
  95                  * Elements of the package are not handled here, they are deleted
  96                  * separately
  97                  */
  98
  99                 /* Free the (variable length) element pointer array */
 100
 101                 obj_pointer = object->package.elements;
 102                 break;
 103
 104                 /*
 105                  * These objects have a possible list of notify handlers.
 106                  * Device object also may have a GPE block.
 107                  */
 108         case ACPI_TYPE_DEVICE:
 109
 110                 if (object->device.gpe_block) {
 111                         (void)acpi_ev_delete_gpe_block(object->device.
 112                                                        gpe_block);
 113                 }
 114
 115                 ACPI_FALLTHROUGH;
 116
 117         case ACPI_TYPE_PROCESSOR:
 118         case ACPI_TYPE_THERMAL:
 119
 120                 /* Walk the address handler list for this object */
 121
 122                 handler_desc = object->common_notify.handler;
 123                 while (handler_desc) {
 124                         next_desc = handler_desc->address_space.next;
 125                         acpi_ut_remove_reference(handler_desc);
 126                         handler_desc = next_desc;
 127                 }
 128                 break;
 129
 130         case ACPI_TYPE_MUTEX:
 131
 132                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 133                                   "***** Mutex %p, OS Mutex %p\n",
 134                                   object, object->mutex.os_mutex));
 135
 136                 if (object == acpi_gbl_global_lock_mutex) {
 137
 138                         /* Global Lock has extra semaphore */
 139
 140                         (void)
 141                             acpi_os_delete_semaphore
 142                             (acpi_gbl_global_lock_semaphore);
 143                         acpi_gbl_global_lock_semaphore = NULL;
 144
 145                         acpi_os_delete_mutex(object->mutex.os_mutex);
 146                         acpi_gbl_global_lock_mutex = NULL;
 147                 } else {
 148                         acpi_ex_unlink_mutex(object);
 149                         acpi_os_delete_mutex(object->mutex.os_mutex);
 150                 }
 151                 break;
 152
 153         case ACPI_TYPE_EVENT:
 154
 155                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 156                                   "***** Event %p, OS Semaphore %p\n",
 157                                   object, object->event.os_semaphore));
 158
 159                 (void)acpi_os_delete_semaphore(object->event.os_semaphore);
 160                 object->event.os_semaphore = NULL;
 161                 break;
 162
 163         case ACPI_TYPE_METHOD:
 164
 165                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 166                                   "***** Method %p\n", object));
 167
 168                 /* Delete the method mutex if it exists */
 169
 170                 if (object->method.mutex) {
 171                         acpi_os_delete_mutex(object->method.mutex->mutex.
 172                                              os_mutex);
 173                         acpi_ut_delete_object_desc(object->method.mutex);
 174                         object->method.mutex = NULL;
 175                 }
 176
 177                 if (object->method.node) {
 178                         object->method.node = NULL;
 179                 }
 180                 break;
 181
 182         case ACPI_TYPE_REGION:
 183
 184                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 185                                   "***** Region %p\n", object));
 186
 187                 /*
 188                  * Update address_range list. However, only permanent regions
 189                  * are installed in this list. (Not created within a method)
 190                  */
 191                 if (!(object->region.node->flags & ANOBJ_TEMPORARY)) {
 192                         acpi_ut_remove_address_range(object->region.space_id,
 193                                                      object->region.node);
 194                 }
 195
 196                 second_desc = acpi_ns_get_secondary_object(object);
 197                 if (second_desc) {
 198                         /*
 199                          * Free the region_context if and only if the handler is one of the
 200                          * default handlers -- and therefore, we created the context object
 201                          * locally, it was not created by an external caller.
 202                          */
 203                         handler_desc = object->region.handler;
 204                         if (handler_desc) {
 205                                 next_desc =
 206                                     handler_desc->address_space.region_list;
 207                                 start_desc = next_desc;
 208                                 last_obj_ptr =
 209                                     &handler_desc->address_space.region_list;
 210
 211                                 /* Remove the region object from the handler list */
 212
 213                                 while (next_desc) {
 214                                         if (next_desc == object) {
 215                                                 *last_obj_ptr =
 216                                                     next_desc->region.next;
 217                                                 break;
 218                                         }
 219
 220                                         /* Walk the linked list of handlers */
 221
 222                                         last_obj_ptr = &next_desc->region.next;
 223                                         next_desc = next_desc->region.next;
 224
 225                                         /* Prevent infinite loop if list is corrupted */
 226
 227                                         if (next_desc == start_desc) {
 228                                                 ACPI_ERROR((AE_INFO,
 229                                                             "Circular region list in address handler object %p",
 230                                                             handler_desc));
 231                                                 return_VOID;
 232                                         }
 233                                 }
 234
 235                                 if (handler_desc->address_space.handler_flags &
 236                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
 237
 238                                         /* Deactivate region and free region context */
 239
 240                                         if (handler_desc->address_space.setup) {
 241                                                 (void)handler_desc->
 242                                                     address_space.setup(object,
 243                                                                         ACPI_REGION_DEACTIVATE,
 244                                                                         handler_desc->
 245                                                                         address_space.
 246                                                                         context,
 247                                                                         &second_desc->
 248                                                                         extra.
 249                                                                         region_context);
 250                                         }
 251                                 }
 252
 253                                 acpi_ut_remove_reference(handler_desc);
 254                         }
 255
 256                         /* Now we can free the Extra object */
 257
 258                         acpi_ut_delete_object_desc(second_desc);
 259                 }
 260                 if (object->field.internal_pcc_buffer) {
 261                         ACPI_FREE(object->field.internal_pcc_buffer);
 262                 }
 263
 264                 break;
 265
 266         case ACPI_TYPE_BUFFER_FIELD:
 267
 268                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 269                                   "***** Buffer Field %p\n", object));
 270
 271                 second_desc = acpi_ns_get_secondary_object(object);
 272                 if (second_desc) {
 273                         acpi_ut_delete_object_desc(second_desc);
 274                 }
 275                 break;
 276
 277         case ACPI_TYPE_LOCAL_BANK_FIELD:
 278
 279                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 280                                   "***** Bank Field %p\n", object));
 281
 282                 second_desc = acpi_ns_get_secondary_object(object);
 283                 if (second_desc) {
 284                         acpi_ut_delete_object_desc(second_desc);
 285                 }
 286                 break;
 287
 288         case ACPI_TYPE_LOCAL_ADDRESS_HANDLER:
 289
 290                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 291                                   "***** Address handler %p\n", object));
 292
 293                 acpi_os_delete_mutex(object->address_space.context_mutex);
 294                 break;
 295
 296         default:
 297
 298                 break;
 299         }
 300
 301         /* Free any allocated memory (pointer within the object) found above */
 302
 303         if (obj_pointer) {
 304                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 305                                   "Deleting Object Subptr %p\n", obj_pointer));
 306                 ACPI_FREE(obj_pointer);
 307         }
 308
 309         /* Now the object can be safely deleted */
 310
 311         ACPI_DEBUG_PRINT_RAW((ACPI_DB_ALLOCATIONS,
 312                               "%s: Deleting Object %p [%s]\n",
 313                               ACPI_GET_FUNCTION_NAME, object,
 314                               acpi_ut_get_object_type_name(object)));
 315
 316         acpi_ut_delete_object_desc(object);
 317         return_VOID;
 318 }
 319
 320 /*******************************************************************************
 321  *
 322  * FUNCTION:    acpi_ut_delete_internal_object_list
 323  *
 324  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
 325  *
 326  * RETURN:      None
 327  *
 328  * DESCRIPTION: This function deletes an internal object list, including both
 329  *              simple objects and package objects
 330  *
 331  ******************************************************************************/
 332
 333 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
 334 {
 335         union acpi_operand_object **internal_obj;
 336
 337         ACPI_FUNCTION_ENTRY();
 338
 339         /* Walk the null-terminated internal list */
 340
 341         for (internal_obj = obj_list; *internal_obj; internal_obj++) {
 342                 acpi_ut_remove_reference(*internal_obj);
 343         }
 344
 345         /* Free the combined parameter pointer list and object array */
 346
 347         ACPI_FREE(obj_list);
 348         return;
 349 }
 350
 351 /*******************************************************************************
 352  *
 353  * FUNCTION:    acpi_ut_update_ref_count
 354  *
 355  * PARAMETERS:  object          - Object whose ref count is to be updated
 356  *              action          - What to do (REF_INCREMENT or REF_DECREMENT)
 357  *
 358  * RETURN:      None. Sets new reference count within the object
 359  *
 360  * DESCRIPTION: Modify the reference count for an internal acpi object
 361  *
 362  ******************************************************************************/
 363
 364 static void
 365 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
 366 {
 367         u16 original_count;
 368         u16 new_count = 0;
 369         acpi_cpu_flags lock_flags;
 370         char *message;
 371
 372         ACPI_FUNCTION_NAME(ut_update_ref_count);
 373
 374         if (!object) {
 375                 return;
 376         }
 377
 378         /*
 379          * Always get the reference count lock. Note: Interpreter and/or
 380          * Namespace is not always locked when this function is called.
 381          */
 382         lock_flags = acpi_os_acquire_lock(acpi_gbl_reference_count_lock);
 383         original_count = object->common.reference_count;
 384
 385         /* Perform the reference count action (increment, decrement) */
 386
 387         switch (action) {
 388         case REF_INCREMENT:
 389
 390                 new_count = original_count + 1;
 391                 object->common.reference_count = new_count;
 392                 acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
 393
 394                 /* The current reference count should never be zero here */
 395
 396                 if (!original_count) {
 397                         ACPI_WARNING((AE_INFO,
 398                                       "Obj %p, Reference Count was zero before increment\n",
 399                                       object));
 400                 }
 401
 402                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 403                                   "Obj %p Type %.2X [%s] Refs %.2X [Incremented]\n",
 404                                   object, object->common.type,
 405                                   acpi_ut_get_object_type_name(object),
 406                                   new_count));
 407                 message = "Incremement";
 408                 break;
 409
 410         case REF_DECREMENT:
 411
 412                 /* The current reference count must be non-zero */
 413
 414                 if (original_count) {
 415                         new_count = original_count - 1;
 416                         object->common.reference_count = new_count;
 417                 }
 418
 419                 acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
 420
 421                 if (!original_count) {
 422                         ACPI_WARNING((AE_INFO,
 423                                       "Obj %p, Reference Count is already zero, cannot decrement\n",
 424                                       object));
 425                 }
 426
 427                 ACPI_DEBUG_PRINT_RAW((ACPI_DB_ALLOCATIONS,
 428                                       "%s: Obj %p Type %.2X Refs %.2X [Decremented]\n",
 429                                       ACPI_GET_FUNCTION_NAME, object,
 430                                       object->common.type, new_count));
 431
 432                 /* Actually delete the object on a reference count of zero */
 433
 434                 if (new_count == 0) {
 435                         acpi_ut_delete_internal_obj(object);
 436                 }
 437                 message = "Decrement";
 438                 break;
 439
 440         default:
 441
 442                 acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
 443                 ACPI_ERROR((AE_INFO, "Unknown Reference Count action (0x%X)",
 444                             action));
 445                 return;
 446         }
 447
 448         /*
 449          * Sanity check the reference count, for debug purposes only.
 450          * (A deleted object will have a huge reference count)
 451          */
 452         if (new_count > ACPI_MAX_REFERENCE_COUNT) {
 453                 ACPI_WARNING((AE_INFO,
 454                               "Large Reference Count (0x%X) in object %p, Type=0x%.2X Operation=%s",
 455                               new_count, object, object->common.type, message));
 456         }
 457 }
 458
 459 /*******************************************************************************
 460  *
 461  * FUNCTION:    acpi_ut_update_object_reference
 462  *
 463  * PARAMETERS:  object              - Increment or decrement the ref count for
 464  *                                    this object and all sub-objects
 465  *              action              - Either REF_INCREMENT or REF_DECREMENT
 466  *
 467  * RETURN:      Status
 468  *
 469  * DESCRIPTION: Increment or decrement the object reference count
 470  *
 471  * Object references are incremented when:
 472  * 1) An object is attached to a Node (namespace object)
 473  * 2) An object is copied (all subobjects must be incremented)
 474  *
 475  * Object references are decremented when:
 476  * 1) An object is detached from an Node
 477  *
 478  ******************************************************************************/
 479
 480 acpi_status
 481 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 482 {
 483         acpi_status status = AE_OK;
 484         union acpi_generic_state *state_list = NULL;
 485         union acpi_operand_object *next_object = NULL;
 486         union acpi_operand_object *prev_object;
 487         union acpi_generic_state *state;
 488         u32 i;
 489
 490         ACPI_FUNCTION_NAME(ut_update_object_reference);
 491
 492         while (object) {
 493
 494                 /* Make sure that this isn't a namespace handle */
 495
 496                 if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
 497                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 498                                           "Object %p is NS handle\n", object));
 499                         return (AE_OK);
 500                 }
 501
 502                 /*
 503                  * All sub-objects must have their reference count updated
 504                  * also. Different object types have different subobjects.
 505                  */
 506                 switch (object->common.type) {
 507                 case ACPI_TYPE_DEVICE:
 508                 case ACPI_TYPE_PROCESSOR:
 509                 case ACPI_TYPE_POWER:
 510                 case ACPI_TYPE_THERMAL:
 511                         /*
 512                          * Update the notify objects for these types (if present)
 513                          * Two lists, system and device notify handlers.
 514                          */
 515                         for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
 516                                 prev_object =
 517                                     object->common_notify.notify_list[i];
 518                                 while (prev_object) {
 519                                         next_object =
 520                                             prev_object->notify.next[i];
 521                                         acpi_ut_update_ref_count(prev_object,
 522                                                                  action);
 523                                         prev_object = next_object;
 524                                 }
 525                         }
 526                         break;
 527
 528                 case ACPI_TYPE_PACKAGE:
 529                         /*
 530                          * We must update all the sub-objects of the package,
 531                          * each of whom may have their own sub-objects.
 532                          */
 533                         for (i = 0; i < object->package.count; i++) {
 534                                 /*
 535                                  * Null package elements are legal and can be simply
 536                                  * ignored.
 537                                  */
 538                                 next_object = object->package.elements[i];
 539                                 if (!next_object) {
 540                                         continue;
 541                                 }
 542
 543                                 switch (next_object->common.type) {
 544                                 case ACPI_TYPE_INTEGER:
 545                                 case ACPI_TYPE_STRING:
 546                                 case ACPI_TYPE_BUFFER:
 547                                         /*
 548                                          * For these very simple sub-objects, we can just
 549                                          * update the reference count here and continue.
 550                                          * Greatly increases performance of this operation.
 551                                          */
 552                                         acpi_ut_update_ref_count(next_object,
 553                                                                  action);
 554                                         break;
 555
 556                                 default:
 557                                         /*
 558                                          * For complex sub-objects, push them onto the stack
 559                                          * for later processing (this eliminates recursion.)
 560                                          */
 561                                         status =
 562                                             acpi_ut_create_update_state_and_push
 563                                             (next_object, action, &state_list);
 564                                         if (ACPI_FAILURE(status)) {
 565                                                 goto error_exit;
 566                                         }
 567                                         break;
 568                                 }
 569                         }
 570
 571                         next_object = NULL;
 572                         break;
 573
 574                 case ACPI_TYPE_BUFFER_FIELD:
 575
 576                         next_object = object->buffer_field.buffer_obj;
 577                         break;
 578
 579                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 580
 581                         next_object = object->bank_field.bank_obj;
 582                         status =
 583                             acpi_ut_create_update_state_and_push(object->
 584                                                                  bank_field.
 585                                                                  region_obj,
 586                                                                  action,
 587                                                                  &state_list);
 588                         if (ACPI_FAILURE(status)) {
 589                                 goto error_exit;
 590                         }
 591                         break;
 592
 593                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 594
 595                         next_object = object->index_field.index_obj;
 596                         status =
 597                             acpi_ut_create_update_state_and_push(object->
 598                                                                  index_field.
 599                                                                  data_obj,
 600                                                                  action,
 601                                                                  &state_list);
 602                         if (ACPI_FAILURE(status)) {
 603                                 goto error_exit;
 604                         }
 605                         break;
 606
 607                 case ACPI_TYPE_LOCAL_REFERENCE:
 608                         /*
 609                          * The target of an Index (a package, string, or buffer) or a named
 610                          * reference must track changes to the ref count of the index or
 611                          * target object.
 612                          */
 613                         if ((object->reference.class == ACPI_REFCLASS_INDEX) ||
 614                             (object->reference.class == ACPI_REFCLASS_NAME)) {
 615                                 next_object = object->reference.object;
 616                         }
 617                         break;
 618
 619                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 620                 case ACPI_TYPE_REGION:
 621                 default:
 622
 623                         break;  /* No subobjects for all other types */
 624                 }
 625
 626                 /*
 627                  * Now we can update the count in the main object. This can only
 628                  * happen after we update the sub-objects in case this causes the
 629                  * main object to be deleted.
 630                  */
 631                 acpi_ut_update_ref_count(object, action);
 632                 object = NULL;
 633
 634                 /* Move on to the next object to be updated */
 635
 636                 if (next_object) {
 637                         object = next_object;
 638                         next_object = NULL;
 639                 } else if (state_list) {
 640                         state = acpi_ut_pop_generic_state(&state_list);
 641                         object = state->update.object;
 642                         acpi_ut_delete_generic_state(state);
 643                 }
 644         }
 645
 646         return (AE_OK);
 647
 648 error_exit:
 649
 650         ACPI_EXCEPTION((AE_INFO, status,
 651                         "Could not update object reference count"));
 652
 653         /* Free any stacked Update State objects */
 654
 655         while (state_list) {
 656                 state = acpi_ut_pop_generic_state(&state_list);
 657                 acpi_ut_delete_generic_state(state);
 658         }
 659
 660         return (status);
 661 }
 662
 663 /*******************************************************************************
 664  *
 665  * FUNCTION:    acpi_ut_add_reference
 666  *
 667  * PARAMETERS:  object          - Object whose reference count is to be
 668  *                                incremented
 669  *
 670  * RETURN:      None
 671  *
 672  * DESCRIPTION: Add one reference to an ACPI object
 673  *
 674  ******************************************************************************/
 675
 676 void acpi_ut_add_reference(union acpi_operand_object *object)
 677 {
 678
 679         ACPI_FUNCTION_NAME(ut_add_reference);
 680
 681         /* Ensure that we have a valid object */
 682
 683         if (!acpi_ut_valid_internal_object(object)) {
 684                 return;
 685         }
 686
 687         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 688                           "Obj %p Current Refs=%X [To Be Incremented]\n",
 689                           object, object->common.reference_count));
 690
 691         /* Increment the reference count */
 692
 693         (void)acpi_ut_update_object_reference(object, REF_INCREMENT);
 694         return;
 695 }
 696
 697 /*******************************************************************************
 698  *
 699  * FUNCTION:    acpi_ut_remove_reference
 700  *
 701  * PARAMETERS:  object         - Object whose ref count will be decremented
 702  *
 703  * RETURN:      None
 704  *
 705  * DESCRIPTION: Decrement the reference count of an ACPI internal object
 706  *
 707  ******************************************************************************/
 708
 709 void acpi_ut_remove_reference(union acpi_operand_object *object)
 710 {
 711
 712         ACPI_FUNCTION_NAME(ut_remove_reference);
 713
 714         /*
 715          * Allow a NULL pointer to be passed in, just ignore it. This saves
 716          * each caller from having to check. Also, ignore NS nodes.
 717          */
 718         if (!object ||
 719             (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
 720                 return;
 721         }
 722
 723         /* Ensure that we have a valid object */
 724
 725         if (!acpi_ut_valid_internal_object(object)) {
 726                 return;
 727         }
 728
 729         ACPI_DEBUG_PRINT_RAW((ACPI_DB_ALLOCATIONS,
 730                               "%s: Obj %p Current Refs=%X [To Be Decremented]\n",
 731                               ACPI_GET_FUNCTION_NAME, object,
 732                               object->common.reference_count));
 733
 734         /*
 735          * Decrement the reference count, and only actually delete the object
 736          * if the reference count becomes 0. (Must also decrement the ref count
 737          * of all subobjects!)
 738          */
 739         (void)acpi_ut_update_object_reference(object, REF_DECREMENT);
 740         return;
 741 }