src/backend/utils/resowner/resowner.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * resowner.c
   4  *        POSTGRES resource owner management code.
   5  *
   6  * Query-lifespan resources are tracked by associating them with
   7  * ResourceOwner objects.  This provides a simple mechanism for ensuring
   8  * that such resources are freed at the right time.
   9  * See utils/resowner/README for more info.
  10  *
  11  *
  12  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
  13  * Portions Copyright (c) 1994, Regents of the University of California
  14  *
  15  *
  16  * IDENTIFICATION
  17  *        $PostgreSQL$
  18  *
  19  *-------------------------------------------------------------------------
  20  */
  21 #include "postgres.h"
  22
  23 #include "access/hash.h"
  24 #include "storage/bufmgr.h"
  25 #include "storage/proc.h"
  26 #include "utils/memutils.h"
  27 #include "utils/rel.h"
  28 #include "utils/resowner.h"
  29 #include "utils/snapmgr.h"
  30
  31
  32 /*
  33  * ResourceOwner objects look like this
  34  */
  35 typedef struct ResourceOwnerData
  36 {
  37         ResourceOwner parent;           /* NULL if no parent (toplevel owner) */
  38         ResourceOwner firstchild;       /* head of linked list of children */
  39         ResourceOwner nextchild;        /* next child of same parent */
  40         const char *name;                       /* name (just for debugging) */
  41
  42         /* We have built-in support for remembering owned buffers */
  43         int                     nbuffers;               /* number of owned buffer pins */
  44         Buffer     *buffers;            /* dynamically allocated array */
  45         int                     maxbuffers;             /* currently allocated array size */
  46
  47         /* We have built-in support for remembering catcache references */
  48         int                     ncatrefs;               /* number of owned catcache pins */
  49         HeapTuple  *catrefs;            /* dynamically allocated array */
  50         int                     maxcatrefs;             /* currently allocated array size */
  51
  52         int                     ncatlistrefs;   /* number of owned catcache-list pins */
  53         CatCList  **catlistrefs;        /* dynamically allocated array */
  54         int                     maxcatlistrefs; /* currently allocated array size */
  55
  56         /* We have built-in support for remembering relcache references */
  57         int                     nrelrefs;               /* number of owned relcache pins */
  58         Relation   *relrefs;            /* dynamically allocated array */
  59         int                     maxrelrefs;             /* currently allocated array size */
  60
  61         /* We have built-in support for remembering plancache references */
  62         int                     nplanrefs;              /* number of owned plancache pins */
  63         CachedPlan **planrefs;          /* dynamically allocated array */
  64         int                     maxplanrefs;    /* currently allocated array size */
  65
  66         /* We have built-in support for remembering tupdesc references */
  67         int                     ntupdescs;              /* number of owned tupdesc references */
  68         TupleDesc  *tupdescs;           /* dynamically allocated array */
  69         int                     maxtupdescs;    /* currently allocated array size */
  70
  71         /* We have built-in support for remembering snapshot references */
  72         int                     nsnapshots;             /* number of owned snapshot references */
  73         Snapshot   *snapshots;          /* dynamically allocated array */
  74         int                     maxsnapshots;   /* currently allocated array size */
  75 } ResourceOwnerData;
  76
  77
  78 /*****************************************************************************
  79  *        GLOBAL MEMORY                                                                                                                  *
  80  *****************************************************************************/
  81
  82 ResourceOwner CurrentResourceOwner = NULL;
  83 ResourceOwner CurTransactionResourceOwner = NULL;
  84 ResourceOwner TopTransactionResourceOwner = NULL;
  85
  86 /*
  87  * List of add-on callbacks for resource releasing
  88  */
  89 typedef struct ResourceReleaseCallbackItem
  90 {
  91         struct ResourceReleaseCallbackItem *next;
  92         ResourceReleaseCallback callback;
  93         void       *arg;
  94 } ResourceReleaseCallbackItem;
  95
  96 static ResourceReleaseCallbackItem *ResourceRelease_callbacks = NULL;
  97
  98
  99 /* Internal routines */
 100 static void ResourceOwnerReleaseInternal(ResourceOwner owner,
 101                                                          ResourceReleasePhase phase,
 102                                                          bool isCommit,
 103                                                          bool isTopLevel);
 104 static void PrintRelCacheLeakWarning(Relation rel);
 105 static void PrintPlanCacheLeakWarning(CachedPlan *plan);
 106 static void PrintTupleDescLeakWarning(TupleDesc tupdesc);
 107 static void PrintSnapshotLeakWarning(Snapshot snapshot);
 108
 109
 110 /*****************************************************************************
 111  *        EXPORTED ROUTINES                                                                                                              *
 112  *****************************************************************************/
 113
 114
 115 /*
 116  * ResourceOwnerCreate
 117  *              Create an empty ResourceOwner.
 118  *
 119  * All ResourceOwner objects are kept in TopMemoryContext, since they should
 120  * only be freed explicitly.
 121  */
 122 ResourceOwner
 123 ResourceOwnerCreate(ResourceOwner parent, const char *name)
 124 {
 125         ResourceOwner owner;
 126
 127         owner = (ResourceOwner) MemoryContextAllocZero(TopMemoryContext,
 128                                                                                                    sizeof(ResourceOwnerData));
 129         owner->name = name;
 130
 131         if (parent)
 132         {
 133                 owner->parent = parent;
 134                 owner->nextchild = parent->firstchild;
 135                 parent->firstchild = owner;
 136         }
 137
 138         return owner;
 139 }
 140
 141 /*
 142  * ResourceOwnerRelease
 143  *              Release all resources owned by a ResourceOwner and its descendants,
 144  *              but don't delete the owner objects themselves.
 145  *
 146  * Note that this executes just one phase of release, and so typically
 147  * must be called three times.  We do it this way because (a) we want to
 148  * do all the recursion separately for each phase, thereby preserving
 149  * the needed order of operations; and (b) xact.c may have other operations
 150  * to do between the phases.
 151  *
 152  * phase: release phase to execute
 153  * isCommit: true for successful completion of a query or transaction,
 154  *                      false for unsuccessful
 155  * isTopLevel: true if completing a main transaction, else false
 156  *
 157  * isCommit is passed because some modules may expect that their resources
 158  * were all released already if the transaction or portal finished normally.
 159  * If so it is reasonable to give a warning (NOT an error) should any
 160  * unreleased resources be present.  When isCommit is false, such warnings
 161  * are generally inappropriate.
 162  *
 163  * isTopLevel is passed when we are releasing TopTransactionResourceOwner
 164  * at completion of a main transaction.  This generally means that *all*
 165  * resources will be released, and so we can optimize things a bit.
 166  */
 167 void
 168 ResourceOwnerRelease(ResourceOwner owner,
 169                                          ResourceReleasePhase phase,
 170                                          bool isCommit,
 171                                          bool isTopLevel)
 172 {
 173         /* Rather than PG_TRY at every level of recursion, set it up once */
 174         ResourceOwner save;
 175
 176         save = CurrentResourceOwner;
 177         PG_TRY();
 178         {
 179                 ResourceOwnerReleaseInternal(owner, phase, isCommit, isTopLevel);
 180         }
 181         PG_CATCH();
 182         {
 183                 CurrentResourceOwner = save;
 184                 PG_RE_THROW();
 185         }
 186         PG_END_TRY();
 187         CurrentResourceOwner = save;
 188 }
 189
 190 static void
 191 ResourceOwnerReleaseInternal(ResourceOwner owner,
 192                                                          ResourceReleasePhase phase,
 193                                                          bool isCommit,
 194                                                          bool isTopLevel)
 195 {
 196         ResourceOwner child;
 197         ResourceOwner save;
 198         ResourceReleaseCallbackItem *item;
 199
 200         /* Recurse to handle descendants */
 201         for (child = owner->firstchild; child != NULL; child = child->nextchild)
 202                 ResourceOwnerReleaseInternal(child, phase, isCommit, isTopLevel);
 203
 204         /*
 205          * Make CurrentResourceOwner point to me, so that ReleaseBuffer etc don't
 206          * get confused.  We needn't PG_TRY here because the outermost level will
 207          * fix it on error abort.
 208          */
 209         save = CurrentResourceOwner;
 210         CurrentResourceOwner = owner;
 211
 212         if (phase == RESOURCE_RELEASE_BEFORE_LOCKS)
 213         {
 214                 /*
 215                  * Release buffer pins.  Note that ReleaseBuffer will remove the
 216                  * buffer entry from my list, so I just have to iterate till there are
 217                  * none.
 218                  *
 219                  * During a commit, there shouldn't be any remaining pins --- that
 220                  * would indicate failure to clean up the executor correctly --- so
 221                  * issue warnings.      In the abort case, just clean up quietly.
 222                  *
 223                  * We are careful to do the releasing back-to-front, so as to avoid
 224                  * O(N^2) behavior in ResourceOwnerForgetBuffer().
 225                  */
 226                 while (owner->nbuffers > 0)
 227                 {
 228                         if (isCommit)
 229                                 PrintBufferLeakWarning(owner->buffers[owner->nbuffers - 1]);
 230                         ReleaseBuffer(owner->buffers[owner->nbuffers - 1]);
 231                 }
 232
 233                 /*
 234                  * Release relcache references.  Note that RelationClose will remove
 235                  * the relref entry from my list, so I just have to iterate till there
 236                  * are none.
 237                  *
 238                  * As with buffer pins, warn if any are left at commit time, and
 239                  * release back-to-front for speed.
 240                  */
 241                 while (owner->nrelrefs > 0)
 242                 {
 243                         if (isCommit)
 244                                 PrintRelCacheLeakWarning(owner->relrefs[owner->nrelrefs - 1]);
 245                         RelationClose(owner->relrefs[owner->nrelrefs - 1]);
 246                 }
 247         }
 248         else if (phase == RESOURCE_RELEASE_LOCKS)
 249         {
 250                 if (isTopLevel)
 251                 {
 252                         /*
 253                          * For a top-level xact we are going to release all locks (or at
 254                          * least all non-session locks), so just do a single lmgr call at
 255                          * the top of the recursion.
 256                          */
 257                         if (owner == TopTransactionResourceOwner)
 258                                 ProcReleaseLocks(isCommit);
 259                 }
 260                 else
 261                 {
 262                         /*
 263                          * Release locks retail.  Note that if we are committing a
 264                          * subtransaction, we do NOT release its locks yet, but transfer
 265                          * them to the parent.
 266                          */
 267                         Assert(owner->parent != NULL);
 268                         if (isCommit)
 269                                 LockReassignCurrentOwner();
 270                         else
 271                                 LockReleaseCurrentOwner();
 272                 }
 273         }
 274         else if (phase == RESOURCE_RELEASE_AFTER_LOCKS)
 275         {
 276                 /*
 277                  * Release catcache references.  Note that ReleaseCatCache will remove
 278                  * the catref entry from my list, so I just have to iterate till there
 279                  * are none.
 280                  *
 281                  * As with buffer pins, warn if any are left at commit time, and
 282                  * release back-to-front for speed.
 283                  */
 284                 while (owner->ncatrefs > 0)
 285                 {
 286                         if (isCommit)
 287                                 PrintCatCacheLeakWarning(owner->catrefs[owner->ncatrefs - 1]);
 288                         ReleaseCatCache(owner->catrefs[owner->ncatrefs - 1]);
 289                 }
 290                 /* Ditto for catcache lists */
 291                 while (owner->ncatlistrefs > 0)
 292                 {
 293                         if (isCommit)
 294                                 PrintCatCacheListLeakWarning(owner->catlistrefs[owner->ncatlistrefs - 1]);
 295                         ReleaseCatCacheList(owner->catlistrefs[owner->ncatlistrefs - 1]);
 296                 }
 297                 /* Ditto for plancache references */
 298                 while (owner->nplanrefs > 0)
 299                 {
 300                         if (isCommit)
 301                                 PrintPlanCacheLeakWarning(owner->planrefs[owner->nplanrefs - 1]);
 302                         ReleaseCachedPlan(owner->planrefs[owner->nplanrefs - 1], true);
 303                 }
 304                 /* Ditto for tupdesc references */
 305                 while (owner->ntupdescs > 0)
 306                 {
 307                         if (isCommit)
 308                                 PrintTupleDescLeakWarning(owner->tupdescs[owner->ntupdescs - 1]);
 309                         DecrTupleDescRefCount(owner->tupdescs[owner->ntupdescs - 1]);
 310                 }
 311                 /* Ditto for snapshot references */
 312                 while (owner->nsnapshots > 0)
 313                 {
 314                         if (isCommit)
 315                                 PrintSnapshotLeakWarning(owner->snapshots[owner->nsnapshots - 1]);
 316                         UnregisterSnapshot(owner->snapshots[owner->nsnapshots - 1]);
 317                 }
 318
 319                 /* Clean up index scans too */
 320                 ReleaseResources_hash();
 321         }
 322
 323         /* Let add-on modules get a chance too */
 324         for (item = ResourceRelease_callbacks; item; item = item->next)
 325                 (*item->callback) (phase, isCommit, isTopLevel, item->arg);
 326
 327         CurrentResourceOwner = save;
 328 }
 329
 330 /*
 331  * ResourceOwnerDelete
 332  *              Delete an owner object and its descendants.
 333  *
 334  * The caller must have already released all resources in the object tree.
 335  */
 336 void
 337 ResourceOwnerDelete(ResourceOwner owner)
 338 {
 339         /* We had better not be deleting CurrentResourceOwner ... */
 340         Assert(owner != CurrentResourceOwner);
 341
 342         /* And it better not own any resources, either */
 343         Assert(owner->nbuffers == 0);
 344         Assert(owner->ncatrefs == 0);
 345         Assert(owner->ncatlistrefs == 0);
 346         Assert(owner->nrelrefs == 0);
 347         Assert(owner->nplanrefs == 0);
 348         Assert(owner->ntupdescs == 0);
 349         Assert(owner->nsnapshots == 0);
 350
 351         /*
 352          * Delete children.  The recursive call will delink the child from me, so
 353          * just iterate as long as there is a child.
 354          */
 355         while (owner->firstchild != NULL)
 356                 ResourceOwnerDelete(owner->firstchild);
 357
 358         /*
 359          * We delink the owner from its parent before deleting it, so that if
 360          * there's an error we won't have deleted/busted owners still attached to
 361          * the owner tree.      Better a leak than a crash.
 362          */
 363         ResourceOwnerNewParent(owner, NULL);
 364
 365         /* And free the object. */
 366         if (owner->buffers)
 367                 pfree(owner->buffers);
 368         if (owner->catrefs)
 369                 pfree(owner->catrefs);
 370         if (owner->catlistrefs)
 371                 pfree(owner->catlistrefs);
 372         if (owner->relrefs)
 373                 pfree(owner->relrefs);
 374         if (owner->planrefs)
 375                 pfree(owner->planrefs);
 376         if (owner->tupdescs)
 377                 pfree(owner->tupdescs);
 378         if (owner->snapshots)
 379                 pfree(owner->snapshots);
 380
 381         pfree(owner);
 382 }
 383
 384 /*
 385  * Fetch parent of a ResourceOwner (returns NULL if top-level owner)
 386  */
 387 ResourceOwner
 388 ResourceOwnerGetParent(ResourceOwner owner)
 389 {
 390         return owner->parent;
 391 }
 392
 393 /*
 394  * Reassign a ResourceOwner to have a new parent
 395  */
 396 void
 397 ResourceOwnerNewParent(ResourceOwner owner,
 398                                            ResourceOwner newparent)
 399 {
 400         ResourceOwner oldparent = owner->parent;
 401
 402         if (oldparent)
 403         {
 404                 if (owner == oldparent->firstchild)
 405                         oldparent->firstchild = owner->nextchild;
 406                 else
 407                 {
 408                         ResourceOwner child;
 409
 410                         for (child = oldparent->firstchild; child; child = child->nextchild)
 411                         {
 412                                 if (owner == child->nextchild)
 413                                 {
 414                                         child->nextchild = owner->nextchild;
 415                                         break;
 416                                 }
 417                         }
 418                 }
 419         }
 420
 421         if (newparent)
 422         {
 423                 Assert(owner != newparent);
 424                 owner->parent = newparent;
 425                 owner->nextchild = newparent->firstchild;
 426                 newparent->firstchild = owner;
 427         }
 428         else
 429         {
 430                 owner->parent = NULL;
 431                 owner->nextchild = NULL;
 432         }
 433 }
 434
 435 /*
 436  * Register or deregister callback functions for resource cleanup
 437  *
 438  * These functions are intended for use by dynamically loaded modules.
 439  * For built-in modules we generally just hardwire the appropriate calls.
 440  *
 441  * Note that the callback occurs post-commit or post-abort, so the callback
 442  * functions can only do noncritical cleanup.
 443  */
 444 void
 445 RegisterResourceReleaseCallback(ResourceReleaseCallback callback, void *arg)
 446 {
 447         ResourceReleaseCallbackItem *item;
 448
 449         item = (ResourceReleaseCallbackItem *)
 450                 MemoryContextAlloc(TopMemoryContext,
 451                                                    sizeof(ResourceReleaseCallbackItem));
 452         item->callback = callback;
 453         item->arg = arg;
 454         item->next = ResourceRelease_callbacks;
 455         ResourceRelease_callbacks = item;
 456 }
 457
 458 void
 459 UnregisterResourceReleaseCallback(ResourceReleaseCallback callback, void *arg)
 460 {
 461         ResourceReleaseCallbackItem *item;
 462         ResourceReleaseCallbackItem *prev;
 463
 464         prev = NULL;
 465         for (item = ResourceRelease_callbacks; item; prev = item, item = item->next)
 466         {
 467                 if (item->callback == callback && item->arg == arg)
 468                 {
 469                         if (prev)
 470                                 prev->next = item->next;
 471                         else
 472                                 ResourceRelease_callbacks = item->next;
 473                         pfree(item);
 474                         break;
 475                 }
 476         }
 477 }
 478
 479
 480 /*
 481  * Make sure there is room for at least one more entry in a ResourceOwner's
 482  * buffer array.
 483  *
 484  * This is separate from actually inserting an entry because if we run out
 485  * of memory, it's critical to do so *before* acquiring the resource.
 486  *
 487  * We allow the case owner == NULL because the bufmgr is sometimes invoked
 488  * outside any transaction (for example, during WAL recovery).
 489  */
 490 void
 491 ResourceOwnerEnlargeBuffers(ResourceOwner owner)
 492 {
 493         int                     newmax;
 494
 495         if (owner == NULL ||
 496                 owner->nbuffers < owner->maxbuffers)
 497                 return;                                 /* nothing to do */
 498
 499         if (owner->buffers == NULL)
 500         {
 501                 newmax = 16;
 502                 owner->buffers = (Buffer *)
 503                         MemoryContextAlloc(TopMemoryContext, newmax * sizeof(Buffer));
 504                 owner->maxbuffers = newmax;
 505         }
 506         else
 507         {
 508                 newmax = owner->maxbuffers * 2;
 509                 owner->buffers = (Buffer *)
 510                         repalloc(owner->buffers, newmax * sizeof(Buffer));
 511                 owner->maxbuffers = newmax;
 512         }
 513 }
 514
 515 /*
 516  * Remember that a buffer pin is owned by a ResourceOwner
 517  *
 518  * Caller must have previously done ResourceOwnerEnlargeBuffers()
 519  *
 520  * We allow the case owner == NULL because the bufmgr is sometimes invoked
 521  * outside any transaction (for example, during WAL recovery).
 522  */
 523 void
 524 ResourceOwnerRememberBuffer(ResourceOwner owner, Buffer buffer)
 525 {
 526         if (owner != NULL)
 527         {
 528                 Assert(owner->nbuffers < owner->maxbuffers);
 529                 owner->buffers[owner->nbuffers] = buffer;
 530                 owner->nbuffers++;
 531         }
 532 }
 533
 534 /*
 535  * Forget that a buffer pin is owned by a ResourceOwner
 536  *
 537  * We allow the case owner == NULL because the bufmgr is sometimes invoked
 538  * outside any transaction (for example, during WAL recovery).
 539  */
 540 void
 541 ResourceOwnerForgetBuffer(ResourceOwner owner, Buffer buffer)
 542 {
 543         if (owner != NULL)
 544         {
 545                 Buffer     *buffers = owner->buffers;
 546                 int                     nb1 = owner->nbuffers - 1;
 547                 int                     i;
 548
 549                 /*
 550                  * Scan back-to-front because it's more likely we are releasing a
 551                  * recently pinned buffer.      This isn't always the case of course, but
 552                  * it's the way to bet.
 553                  */
 554                 for (i = nb1; i >= 0; i--)
 555                 {
 556                         if (buffers[i] == buffer)
 557                         {
 558                                 while (i < nb1)
 559                                 {
 560                                         buffers[i] = buffers[i + 1];
 561                                         i++;
 562                                 }
 563                                 owner->nbuffers = nb1;
 564                                 return;
 565                         }
 566                 }
 567                 elog(ERROR, "buffer %d is not owned by resource owner %s",
 568                          buffer, owner->name);
 569         }
 570 }
 571
 572 /*
 573  * Make sure there is room for at least one more entry in a ResourceOwner's
 574  * catcache reference array.
 575  *
 576  * This is separate from actually inserting an entry because if we run out
 577  * of memory, it's critical to do so *before* acquiring the resource.
 578  */
 579 void
 580 ResourceOwnerEnlargeCatCacheRefs(ResourceOwner owner)
 581 {
 582         int                     newmax;
 583
 584         if (owner->ncatrefs < owner->maxcatrefs)
 585                 return;                                 /* nothing to do */
 586
 587         if (owner->catrefs == NULL)
 588         {
 589                 newmax = 16;
 590                 owner->catrefs = (HeapTuple *)
 591                         MemoryContextAlloc(TopMemoryContext, newmax * sizeof(HeapTuple));
 592                 owner->maxcatrefs = newmax;
 593         }
 594         else
 595         {
 596                 newmax = owner->maxcatrefs * 2;
 597                 owner->catrefs = (HeapTuple *)
 598                         repalloc(owner->catrefs, newmax * sizeof(HeapTuple));
 599                 owner->maxcatrefs = newmax;
 600         }
 601 }
 602
 603 /*
 604  * Remember that a catcache reference is owned by a ResourceOwner
 605  *
 606  * Caller must have previously done ResourceOwnerEnlargeCatCacheRefs()
 607  */
 608 void
 609 ResourceOwnerRememberCatCacheRef(ResourceOwner owner, HeapTuple tuple)
 610 {
 611         Assert(owner->ncatrefs < owner->maxcatrefs);
 612         owner->catrefs[owner->ncatrefs] = tuple;
 613         owner->ncatrefs++;
 614 }
 615
 616 /*
 617  * Forget that a catcache reference is owned by a ResourceOwner
 618  */
 619 void
 620 ResourceOwnerForgetCatCacheRef(ResourceOwner owner, HeapTuple tuple)
 621 {
 622         HeapTuple  *catrefs = owner->catrefs;
 623         int                     nc1 = owner->ncatrefs - 1;
 624         int                     i;
 625
 626         for (i = nc1; i >= 0; i--)
 627         {
 628                 if (catrefs[i] == tuple)
 629                 {
 630                         while (i < nc1)
 631                         {
 632                                 catrefs[i] = catrefs[i + 1];
 633                                 i++;
 634                         }
 635                         owner->ncatrefs = nc1;
 636                         return;
 637                 }
 638         }
 639         elog(ERROR, "catcache reference %p is not owned by resource owner %s",
 640                  tuple, owner->name);
 641 }
 642
 643 /*
 644  * Make sure there is room for at least one more entry in a ResourceOwner's
 645  * catcache-list reference array.
 646  *
 647  * This is separate from actually inserting an entry because if we run out
 648  * of memory, it's critical to do so *before* acquiring the resource.
 649  */
 650 void
 651 ResourceOwnerEnlargeCatCacheListRefs(ResourceOwner owner)
 652 {
 653         int                     newmax;
 654
 655         if (owner->ncatlistrefs < owner->maxcatlistrefs)
 656                 return;                                 /* nothing to do */
 657
 658         if (owner->catlistrefs == NULL)
 659         {
 660                 newmax = 16;
 661                 owner->catlistrefs = (CatCList **)
 662                         MemoryContextAlloc(TopMemoryContext, newmax * sizeof(CatCList *));
 663                 owner->maxcatlistrefs = newmax;
 664         }
 665         else
 666         {
 667                 newmax = owner->maxcatlistrefs * 2;
 668                 owner->catlistrefs = (CatCList **)
 669                         repalloc(owner->catlistrefs, newmax * sizeof(CatCList *));
 670                 owner->maxcatlistrefs = newmax;
 671         }
 672 }
 673
 674 /*
 675  * Remember that a catcache-list reference is owned by a ResourceOwner
 676  *
 677  * Caller must have previously done ResourceOwnerEnlargeCatCacheListRefs()
 678  */
 679 void
 680 ResourceOwnerRememberCatCacheListRef(ResourceOwner owner, CatCList *list)
 681 {
 682         Assert(owner->ncatlistrefs < owner->maxcatlistrefs);
 683         owner->catlistrefs[owner->ncatlistrefs] = list;
 684         owner->ncatlistrefs++;
 685 }
 686
 687 /*
 688  * Forget that a catcache-list reference is owned by a ResourceOwner
 689  */
 690 void
 691 ResourceOwnerForgetCatCacheListRef(ResourceOwner owner, CatCList *list)
 692 {
 693         CatCList  **catlistrefs = owner->catlistrefs;
 694         int                     nc1 = owner->ncatlistrefs - 1;
 695         int                     i;
 696
 697         for (i = nc1; i >= 0; i--)
 698         {
 699                 if (catlistrefs[i] == list)
 700                 {
 701                         while (i < nc1)
 702                         {
 703                                 catlistrefs[i] = catlistrefs[i + 1];
 704                                 i++;
 705                         }
 706                         owner->ncatlistrefs = nc1;
 707                         return;
 708                 }
 709         }
 710         elog(ERROR, "catcache list reference %p is not owned by resource owner %s",
 711                  list, owner->name);
 712 }
 713
 714 /*
 715  * Make sure there is room for at least one more entry in a ResourceOwner's
 716  * relcache reference array.
 717  *
 718  * This is separate from actually inserting an entry because if we run out
 719  * of memory, it's critical to do so *before* acquiring the resource.
 720  */
 721 void
 722 ResourceOwnerEnlargeRelationRefs(ResourceOwner owner)
 723 {
 724         int                     newmax;
 725
 726         if (owner->nrelrefs < owner->maxrelrefs)
 727                 return;                                 /* nothing to do */
 728
 729         if (owner->relrefs == NULL)
 730         {
 731                 newmax = 16;
 732                 owner->relrefs = (Relation *)
 733                         MemoryContextAlloc(TopMemoryContext, newmax * sizeof(Relation));
 734                 owner->maxrelrefs = newmax;
 735         }
 736         else
 737         {
 738                 newmax = owner->maxrelrefs * 2;
 739                 owner->relrefs = (Relation *)
 740                         repalloc(owner->relrefs, newmax * sizeof(Relation));
 741                 owner->maxrelrefs = newmax;
 742         }
 743 }
 744
 745 /*
 746  * Remember that a relcache reference is owned by a ResourceOwner
 747  *
 748  * Caller must have previously done ResourceOwnerEnlargeRelationRefs()
 749  */
 750 void
 751 ResourceOwnerRememberRelationRef(ResourceOwner owner, Relation rel)
 752 {
 753         Assert(owner->nrelrefs < owner->maxrelrefs);
 754         owner->relrefs[owner->nrelrefs] = rel;
 755         owner->nrelrefs++;
 756 }
 757
 758 /*
 759  * Forget that a relcache reference is owned by a ResourceOwner
 760  */
 761 void
 762 ResourceOwnerForgetRelationRef(ResourceOwner owner, Relation rel)
 763 {
 764         Relation   *relrefs = owner->relrefs;
 765         int                     nr1 = owner->nrelrefs - 1;
 766         int                     i;
 767
 768         for (i = nr1; i >= 0; i--)
 769         {
 770                 if (relrefs[i] == rel)
 771                 {
 772                         while (i < nr1)
 773                         {
 774                                 relrefs[i] = relrefs[i + 1];
 775                                 i++;
 776                         }
 777                         owner->nrelrefs = nr1;
 778                         return;
 779                 }
 780         }
 781         elog(ERROR, "relcache reference %s is not owned by resource owner %s",
 782                  RelationGetRelationName(rel), owner->name);
 783 }
 784
 785 /*
 786  * Debugging subroutine
 787  */
 788 static void
 789 PrintRelCacheLeakWarning(Relation rel)
 790 {
 791         elog(WARNING, "relcache reference leak: relation \"%s\" not closed",
 792                  RelationGetRelationName(rel));
 793 }
 794
 795 /*
 796  * Make sure there is room for at least one more entry in a ResourceOwner's
 797  * plancache reference array.
 798  *
 799  * This is separate from actually inserting an entry because if we run out
 800  * of memory, it's critical to do so *before* acquiring the resource.
 801  */
 802 void
 803 ResourceOwnerEnlargePlanCacheRefs(ResourceOwner owner)
 804 {
 805         int                     newmax;
 806
 807         if (owner->nplanrefs < owner->maxplanrefs)
 808                 return;                                 /* nothing to do */
 809
 810         if (owner->planrefs == NULL)
 811         {
 812                 newmax = 16;
 813                 owner->planrefs = (CachedPlan **)
 814                         MemoryContextAlloc(TopMemoryContext, newmax * sizeof(CachedPlan *));
 815                 owner->maxplanrefs = newmax;
 816         }
 817         else
 818         {
 819                 newmax = owner->maxplanrefs * 2;
 820                 owner->planrefs = (CachedPlan **)
 821                         repalloc(owner->planrefs, newmax * sizeof(CachedPlan *));
 822                 owner->maxplanrefs = newmax;
 823         }
 824 }
 825
 826 /*
 827  * Remember that a plancache reference is owned by a ResourceOwner
 828  *
 829  * Caller must have previously done ResourceOwnerEnlargePlanCacheRefs()
 830  */
 831 void
 832 ResourceOwnerRememberPlanCacheRef(ResourceOwner owner, CachedPlan *plan)
 833 {
 834         Assert(owner->nplanrefs < owner->maxplanrefs);
 835         owner->planrefs[owner->nplanrefs] = plan;
 836         owner->nplanrefs++;
 837 }
 838
 839 /*
 840  * Forget that a plancache reference is owned by a ResourceOwner
 841  */
 842 void
 843 ResourceOwnerForgetPlanCacheRef(ResourceOwner owner, CachedPlan *plan)
 844 {
 845         CachedPlan **planrefs = owner->planrefs;
 846         int                     np1 = owner->nplanrefs - 1;
 847         int                     i;
 848
 849         for (i = np1; i >= 0; i--)
 850         {
 851                 if (planrefs[i] == plan)
 852                 {
 853                         while (i < np1)
 854                         {
 855                                 planrefs[i] = planrefs[i + 1];
 856                                 i++;
 857                         }
 858                         owner->nplanrefs = np1;
 859                         return;
 860                 }
 861         }
 862         elog(ERROR, "plancache reference %p is not owned by resource owner %s",
 863                  plan, owner->name);
 864 }
 865
 866 /*
 867  * Debugging subroutine
 868  */
 869 static void
 870 PrintPlanCacheLeakWarning(CachedPlan *plan)
 871 {
 872         elog(WARNING, "plancache reference leak: plan %p not closed", plan);
 873 }
 874
 875 /*
 876  * Make sure there is room for at least one more entry in a ResourceOwner's
 877  * tupdesc reference array.
 878  *
 879  * This is separate from actually inserting an entry because if we run out
 880  * of memory, it's critical to do so *before* acquiring the resource.
 881  */
 882 void
 883 ResourceOwnerEnlargeTupleDescs(ResourceOwner owner)
 884 {
 885         int                     newmax;
 886
 887         if (owner->ntupdescs < owner->maxtupdescs)
 888                 return;                                 /* nothing to do */
 889
 890         if (owner->tupdescs == NULL)
 891         {
 892                 newmax = 16;
 893                 owner->tupdescs = (TupleDesc *)
 894                         MemoryContextAlloc(TopMemoryContext, newmax * sizeof(TupleDesc));
 895                 owner->maxtupdescs = newmax;
 896         }
 897         else
 898         {
 899                 newmax = owner->maxtupdescs * 2;
 900                 owner->tupdescs = (TupleDesc *)
 901                         repalloc(owner->tupdescs, newmax * sizeof(TupleDesc));
 902                 owner->maxtupdescs = newmax;
 903         }
 904 }
 905
 906 /*
 907  * Remember that a tupdesc reference is owned by a ResourceOwner
 908  *
 909  * Caller must have previously done ResourceOwnerEnlargeTupleDescs()
 910  */
 911 void
 912 ResourceOwnerRememberTupleDesc(ResourceOwner owner, TupleDesc tupdesc)
 913 {
 914         Assert(owner->ntupdescs < owner->maxtupdescs);
 915         owner->tupdescs[owner->ntupdescs] = tupdesc;
 916         owner->ntupdescs++;
 917 }
 918
 919 /*
 920  * Forget that a tupdesc reference is owned by a ResourceOwner
 921  */
 922 void
 923 ResourceOwnerForgetTupleDesc(ResourceOwner owner, TupleDesc tupdesc)
 924 {
 925         TupleDesc  *tupdescs = owner->tupdescs;
 926         int                     nt1 = owner->ntupdescs - 1;
 927         int                     i;
 928
 929         for (i = nt1; i >= 0; i--)
 930         {
 931                 if (tupdescs[i] == tupdesc)
 932                 {
 933                         while (i < nt1)
 934                         {
 935                                 tupdescs[i] = tupdescs[i + 1];
 936                                 i++;
 937                         }
 938                         owner->ntupdescs = nt1;
 939                         return;
 940                 }
 941         }
 942         elog(ERROR, "tupdesc reference %p is not owned by resource owner %s",
 943                  tupdesc, owner->name);
 944 }
 945
 946 /*
 947  * Debugging subroutine
 948  */
 949 static void
 950 PrintTupleDescLeakWarning(TupleDesc tupdesc)
 951 {
 952         elog(WARNING,
 953                  "TupleDesc reference leak: TupleDesc %p (%u,%d) still referenced",
 954                  tupdesc, tupdesc->tdtypeid, tupdesc->tdtypmod);
 955 }
 956
 957 /*
 958  * Make sure there is room for at least one more entry in a ResourceOwner's
 959  * snapshot reference array.
 960  *
 961  * This is separate from actually inserting an entry because if we run out
 962  * of memory, it's critical to do so *before* acquiring the resource.
 963  */
 964 void
 965 ResourceOwnerEnlargeSnapshots(ResourceOwner owner)
 966 {
 967         int                     newmax;
 968
 969         if (owner->nsnapshots < owner->maxsnapshots)
 970                 return;                                 /* nothing to do */
 971
 972         if (owner->snapshots == NULL)
 973         {
 974                 newmax = 16;
 975                 owner->snapshots = (Snapshot *)
 976                         MemoryContextAlloc(TopMemoryContext, newmax * sizeof(Snapshot));
 977                 owner->maxsnapshots = newmax;
 978         }
 979         else
 980         {
 981                 newmax = owner->maxsnapshots * 2;
 982                 owner->snapshots = (Snapshot *)
 983                         repalloc(owner->snapshots, newmax * sizeof(Snapshot));
 984                 owner->maxsnapshots = newmax;
 985         }
 986 }
 987
 988 /*
 989  * Remember that a snapshot reference is owned by a ResourceOwner
 990  *
 991  * Caller must have previously done ResourceOwnerEnlargeSnapshots()
 992  */
 993 void
 994 ResourceOwnerRememberSnapshot(ResourceOwner owner, Snapshot snapshot)
 995 {
 996         Assert(owner->nsnapshots < owner->maxsnapshots);
 997         owner->snapshots[owner->nsnapshots] = snapshot;
 998         owner->nsnapshots++;
 999 }
1000
1001 /*
1002  * Forget that a snapshot reference is owned by a ResourceOwner
1003  */
1004 void
1005 ResourceOwnerForgetSnapshot(ResourceOwner owner, Snapshot snapshot)
1006 {
1007         Snapshot   *snapshots = owner->snapshots;
1008         int                     ns1 = owner->nsnapshots - 1;
1009         int                     i;
1010
1011         for (i = ns1; i >= 0; i--)
1012         {
1013                 if (snapshots[i] == snapshot)
1014                 {
1015                         while (i < ns1)
1016                         {
1017                                 snapshots[i] = snapshots[i + 1];
1018                                 i++;
1019                         }
1020                         owner->nsnapshots = ns1;
1021                         return;
1022                 }
1023         }
1024         elog(ERROR, "snapshot reference %p is not owned by resource owner %s",
1025                  snapshot, owner->name);
1026 }
1027
1028 /*
1029  * Debugging subroutine
1030  */
1031 static void
1032 PrintSnapshotLeakWarning(Snapshot snapshot)
1033 {
1034         elog(WARNING,
1035                  "Snapshot reference leak: Snapshot %p still referenced",
1036                  snapshot);
1037 }