Revert 11470f544e
authorAlexander Korotkov <[email protected]>
Mon, 3 Apr 2023 13:54:31 +0000 (16:54 +0300)
committerAlexander Korotkov <[email protected]>
Mon, 3 Apr 2023 13:54:31 +0000 (16:54 +0300)
Discussion: https://postgr.es/m/20230323003003.plgaxjqahjgkuxrk%40awork3.anarazel.de

src/backend/access/heap/heapam_handler.c
src/backend/access/table/tableam.c
src/backend/executor/nodeModifyTable.c
src/include/access/tableam.h
src/include/executor/tuptable.h
src/tools/pgindent/typedefs.list

index 97b5daee9203f3723685202ec9c8678b261d5b8e..e2e35b71eaa03bd3c2de840db671fe7fa42ad7af 100644 (file)
 #include "utils/builtins.h"
 #include "utils/rel.h"
 
-static TM_Result heapam_tuple_lock_internal(Relation relation, ItemPointer tid,
-                                           Snapshot snapshot, TupleTableSlot *slot,
-                                           CommandId cid, LockTupleMode mode,
-                                           LockWaitPolicy wait_policy, uint8 flags,
-                                           TM_FailureData *tmfd, bool updated);
-
 static void reform_and_rewrite_tuple(HeapTuple tuple,
                                     Relation OldHeap, Relation NewHeap,
                                     Datum *values, bool *isnull, RewriteState rwstate);
@@ -305,46 +299,14 @@ heapam_tuple_complete_speculative(Relation relation, TupleTableSlot *slot,
 static TM_Result
 heapam_tuple_delete(Relation relation, ItemPointer tid, CommandId cid,
                    Snapshot snapshot, Snapshot crosscheck, bool wait,
-                   TM_FailureData *tmfd, bool changingPart,
-                   LazyTupleTableSlot *lockedSlot)
+                   TM_FailureData *tmfd, bool changingPart)
 {
-   TM_Result   result;
-
    /*
     * Currently Deleting of index tuples are handled at vacuum, in case if
     * the storage itself is cleaning the dead tuples by itself, it is the
     * time to call the index tuple deletion also.
     */
-   result = heap_delete(relation, tid, cid, crosscheck, wait,
-                        tmfd, changingPart);
-
-   /*
-    * If the tuple has been concurrently updated, then get the lock on it.
-    * (Do this if caller asked for tat by providing a 'lockedSlot'.) With the
-    * lock held retry of delete should succeed even if there are more
-    * concurrent update attempts.
-    */
-   if (result == TM_Updated && lockedSlot)
-   {
-       TupleTableSlot *evalSlot;
-
-       Assert(wait);
-
-       evalSlot = LAZY_TTS_EVAL(lockedSlot);
-       result = heapam_tuple_lock_internal(relation, tid, snapshot,
-                                           evalSlot, cid, LockTupleExclusive,
-                                           LockWaitBlock,
-                                           TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
-                                           tmfd, true);
-
-       if (result == TM_Ok)
-       {
-           tmfd->traversed = true;
-           return TM_Updated;
-       }
-   }
-
-   return result;
+   return heap_delete(relation, tid, cid, crosscheck, wait, tmfd, changingPart);
 }
 
 
@@ -352,8 +314,7 @@ static TM_Result
 heapam_tuple_update(Relation relation, ItemPointer otid, TupleTableSlot *slot,
                    CommandId cid, Snapshot snapshot, Snapshot crosscheck,
                    bool wait, TM_FailureData *tmfd,
-                   LockTupleMode *lockmode, TU_UpdateIndexes *update_indexes,
-                   LazyTupleTableSlot *lockedSlot)
+                   LockTupleMode *lockmode, TU_UpdateIndexes *update_indexes)
 {
    bool        shouldFree = true;
    HeapTuple   tuple = ExecFetchSlotHeapTuple(slot, true, &shouldFree);
@@ -391,32 +352,6 @@ heapam_tuple_update(Relation relation, ItemPointer otid, TupleTableSlot *slot,
    if (shouldFree)
        pfree(tuple);
 
-   /*
-    * If the tuple has been concurrently updated, then get the lock on it.
-    * (Do this if caller asked for tat by providing a 'lockedSlot'.) With the
-    * lock held retry of update should succeed even if there are more
-    * concurrent update attempts.
-    */
-   if (result == TM_Updated && lockedSlot)
-   {
-       TupleTableSlot *evalSlot;
-
-       Assert(wait);
-
-       evalSlot = LAZY_TTS_EVAL(lockedSlot);
-       result = heapam_tuple_lock_internal(relation, otid, snapshot,
-                                           evalSlot, cid, *lockmode,
-                                           LockWaitBlock,
-                                           TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
-                                           tmfd, true);
-
-       if (result == TM_Ok)
-       {
-           tmfd->traversed = true;
-           return TM_Updated;
-       }
-   }
-
    return result;
 }
 
@@ -425,26 +360,10 @@ heapam_tuple_lock(Relation relation, ItemPointer tid, Snapshot snapshot,
                  TupleTableSlot *slot, CommandId cid, LockTupleMode mode,
                  LockWaitPolicy wait_policy, uint8 flags,
                  TM_FailureData *tmfd)
-{
-   return heapam_tuple_lock_internal(relation, tid, snapshot, slot, cid,
-                                     mode, wait_policy, flags, tmfd, false);
-}
-
-/*
- * This routine does the work for heapam_tuple_lock(), but also support
- * `updated` argument to re-use the work done by heapam_tuple_update() or
- * heapam_tuple_delete() on figuring out that tuple was concurrently updated.
- */
-static TM_Result
-heapam_tuple_lock_internal(Relation relation, ItemPointer tid,
-                          Snapshot snapshot, TupleTableSlot *slot,
-                          CommandId cid, LockTupleMode mode,
-                          LockWaitPolicy wait_policy, uint8 flags,
-                          TM_FailureData *tmfd, bool updated)
 {
    BufferHeapTupleTableSlot *bslot = (BufferHeapTupleTableSlot *) slot;
    TM_Result   result;
-   Buffer      buffer = InvalidBuffer;
+   Buffer      buffer;
    HeapTuple   tuple = &bslot->base.tupdata;
    bool        follow_updates;
 
@@ -455,26 +374,16 @@ heapam_tuple_lock_internal(Relation relation, ItemPointer tid,
 
 tuple_lock_retry:
    tuple->t_self = *tid;
-   if (!updated)
-       result = heap_lock_tuple(relation, tuple, cid, mode, wait_policy,
-                                follow_updates, &buffer, tmfd);
-   else
-       result = TM_Updated;
+   result = heap_lock_tuple(relation, tuple, cid, mode, wait_policy,
+                            follow_updates, &buffer, tmfd);
 
    if (result == TM_Updated &&
        (flags & TUPLE_LOCK_FLAG_FIND_LAST_VERSION))
    {
-       if (!updated)
-       {
-           /* Should not encounter speculative tuple on recheck */
-           Assert(!HeapTupleHeaderIsSpeculative(tuple->t_data));
+       /* Should not encounter speculative tuple on recheck */
+       Assert(!HeapTupleHeaderIsSpeculative(tuple->t_data));
 
-           ReleaseBuffer(buffer);
-       }
-       else
-       {
-           updated = false;
-       }
+       ReleaseBuffer(buffer);
 
        if (!ItemPointerEquals(&tmfd->ctid, &tuple->t_self))
        {
index 2a1a6ced3c76885e071629a73537527ae0ed6c9c..a5e6c92f35eec75a743263b5b3904feb547c8f10 100644 (file)
@@ -306,8 +306,7 @@ simple_table_tuple_delete(Relation rel, ItemPointer tid, Snapshot snapshot)
                                GetCurrentCommandId(true),
                                snapshot, InvalidSnapshot,
                                true /* wait for commit */ ,
-                               &tmfd, false /* changingPart */ ,
-                               NULL);
+                               &tmfd, false /* changingPart */ );
 
    switch (result)
    {
@@ -356,8 +355,7 @@ simple_table_tuple_update(Relation rel, ItemPointer otid,
                                GetCurrentCommandId(true),
                                snapshot, InvalidSnapshot,
                                true /* wait for commit */ ,
-                               &tmfd, &lockmode, update_indexes,
-                               NULL);
+                               &tmfd, &lockmode, update_indexes);
 
    switch (result)
    {
index e35037568181bf93f7a18466b71799c316154df2..93ebfdbb0d83080ea4676d7a4fd07c3d1e80f887 100644 (file)
@@ -1324,62 +1324,26 @@ ExecDeletePrologue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
    return true;
 }
 
-/*
- * The implementation for LazyTupleTableSlot wrapper for EPQ slot to be passed
- * to table_tuple_update()/table_tuple_delete().
- */
-typedef struct
-{
-   EPQState   *epqstate;
-   ResultRelInfo *resultRelInfo;
-} GetEPQSlotArg;
-
-static TupleTableSlot *
-GetEPQSlot(void *arg)
-{
-   GetEPQSlotArg *slotArg = (GetEPQSlotArg *) arg;
-
-   return EvalPlanQualSlot(slotArg->epqstate,
-                           slotArg->resultRelInfo->ri_RelationDesc,
-                           slotArg->resultRelInfo->ri_RangeTableIndex);
-}
-
 /*
  * ExecDeleteAct -- subroutine for ExecDelete
  *
  * Actually delete the tuple from a plain table.
  *
- * If the 'lockUpdated' flag is set and the target tuple is updated, then
- * the latest version gets locked and fetched into the EPQ slot.
- *
  * Caller is in charge of doing EvalPlanQual as necessary
  */
 static TM_Result
 ExecDeleteAct(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
-             ItemPointer tupleid, bool changingPart, bool lockUpdated)
+             ItemPointer tupleid, bool changingPart)
 {
    EState     *estate = context->estate;
-   GetEPQSlotArg slotArg = {context->epqstate, resultRelInfo};
-   LazyTupleTableSlot lazyEPQSlot,
-              *lazyEPQSlotPtr;
 
-   if (lockUpdated)
-   {
-       MAKE_LAZY_TTS(&lazyEPQSlot, GetEPQSlot, &slotArg);
-       lazyEPQSlotPtr = &lazyEPQSlot;
-   }
-   else
-   {
-       lazyEPQSlotPtr = NULL;
-   }
    return table_tuple_delete(resultRelInfo->ri_RelationDesc, tupleid,
                              estate->es_output_cid,
                              estate->es_snapshot,
                              estate->es_crosscheck_snapshot,
                              true /* wait for commit */ ,
                              &context->tmfd,
-                             changingPart,
-                             lazyEPQSlotPtr);
+                             changingPart);
 }
 
 /*
@@ -1524,8 +1488,7 @@ ExecDelete(ModifyTableContext *context,
         * transaction-snapshot mode transactions.
         */
 ldelete:
-       result = ExecDeleteAct(context, resultRelInfo, tupleid, changingPart,
-                              !IsolationUsesXactSnapshot());
+       result = ExecDeleteAct(context, resultRelInfo, tupleid, changingPart);
 
        switch (result)
        {
@@ -1578,49 +1541,103 @@ ldelete:
                                 errmsg("could not serialize access due to concurrent update")));
 
                    /*
-                    * ExecDeleteAct() has already locked the old tuple for
-                    * us. Now we need to copy it to the right slot.
+                    * Already know that we're going to need to do EPQ, so
+                    * fetch tuple directly into the right slot.
                     */
                    EvalPlanQualBegin(context->epqstate);
                    inputslot = EvalPlanQualSlot(context->epqstate, resultRelationDesc,
                                                 resultRelInfo->ri_RangeTableIndex);
 
-                   /*
-                    * Save locked table for further processing for RETURNING
-                    * clause.
-                    */
-                   if (processReturning &&
-                       resultRelInfo->ri_projectReturning &&
-                       !resultRelInfo->ri_FdwRoutine)
+                   result = table_tuple_lock(resultRelationDesc, tupleid,
+                                             estate->es_snapshot,
+                                             inputslot, estate->es_output_cid,
+                                             LockTupleExclusive, LockWaitBlock,
+                                             TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
+                                             &context->tmfd);
+
+                   switch (result)
                    {
-                       TupleTableSlot *returningSlot;
+                       case TM_Ok:
+                           Assert(context->tmfd.traversed);
 
-                       returningSlot = ExecGetReturningSlot(estate,
-                                                            resultRelInfo);
-                       ExecCopySlot(returningSlot, inputslot);
-                       ExecMaterializeSlot(returningSlot);
-                   }
+                           /*
+                            * Save locked tuple for further processing of
+                            * RETURNING clause.
+                            */
+                           if (processReturning &&
+                               resultRelInfo->ri_projectReturning &&
+                               !resultRelInfo->ri_FdwRoutine)
+                           {
+                               TupleTableSlot *returningSlot;
+
+                               returningSlot = ExecGetReturningSlot(estate, resultRelInfo);
+                               ExecCopySlot(returningSlot, inputslot);
+                               ExecMaterializeSlot(returningSlot);
+                           }
+
+                           epqslot = EvalPlanQual(context->epqstate,
+                                                  resultRelationDesc,
+                                                  resultRelInfo->ri_RangeTableIndex,
+                                                  inputslot);
+                           if (TupIsNull(epqslot))
+                               /* Tuple not passing quals anymore, exiting... */
+                               return NULL;
+
+                           /*
+                            * If requested, skip delete and pass back the
+                            * updated row.
+                            */
+                           if (epqreturnslot)
+                           {
+                               *epqreturnslot = epqslot;
+                               return NULL;
+                           }
+                           else
+                               goto ldelete;
 
-                   Assert(context->tmfd.traversed);
-                   epqslot = EvalPlanQual(context->epqstate,
-                                          resultRelationDesc,
-                                          resultRelInfo->ri_RangeTableIndex,
-                                          inputslot);
-                   if (TupIsNull(epqslot))
-                       /* Tuple not passing quals anymore, exiting... */
-                       return NULL;
+                       case TM_SelfModified:
 
-                   /*
-                    * If requested, skip delete and pass back the updated
-                    * row.
-                    */
-                   if (epqreturnslot)
-                   {
-                       *epqreturnslot = epqslot;
-                       return NULL;
+                           /*
+                            * This can be reached when following an update
+                            * chain from a tuple updated by another session,
+                            * reaching a tuple that was already updated in
+                            * this transaction. If previously updated by this
+                            * command, ignore the delete, otherwise error
+                            * out.
+                            *
+                            * See also TM_SelfModified response to
+                            * table_tuple_delete() above.
+                            */
+                           if (context->tmfd.cmax != estate->es_output_cid)
+                               ereport(ERROR,
+                                       (errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
+                                        errmsg("tuple to be deleted was already modified by an operation triggered by the current command"),
+                                        errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
+                           return NULL;
+
+                       case TM_Deleted:
+                           /* tuple already deleted; nothing to do */
+                           return NULL;
+
+                       default:
+
+                           /*
+                            * TM_Invisible should be impossible because we're
+                            * waiting for updated row versions, and would
+                            * already have errored out if the first version
+                            * is invisible.
+                            *
+                            * TM_Updated should be impossible, because we're
+                            * locking the latest version via
+                            * TUPLE_LOCK_FLAG_FIND_LAST_VERSION.
+                            */
+                           elog(ERROR, "unexpected table_tuple_lock status: %u",
+                                result);
+                           return NULL;
                    }
-                   else
-                       goto ldelete;
+
+                   Assert(false);
+                   break;
                }
 
            case TM_Deleted:
@@ -1965,15 +1982,12 @@ ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo,
 static TM_Result
 ExecUpdateAct(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
              ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
-             bool canSetTag, bool lockUpdated, UpdateContext *updateCxt)
+             bool canSetTag, UpdateContext *updateCxt)
 {
    EState     *estate = context->estate;
    Relation    resultRelationDesc = resultRelInfo->ri_RelationDesc;
    bool        partition_constraint_failed;
    TM_Result   result;
-   GetEPQSlotArg slotArg = {context->epqstate, resultRelInfo};
-   LazyTupleTableSlot lazyEPQSlot,
-              *lazyEPQSlotPtr;
 
    updateCxt->crossPartUpdate = false;
 
@@ -2099,23 +2113,13 @@ lreplace:
     * for referential integrity updates in transaction-snapshot mode
     * transactions.
     */
-   if (lockUpdated)
-   {
-       MAKE_LAZY_TTS(&lazyEPQSlot, GetEPQSlot, &slotArg);
-       lazyEPQSlotPtr = &lazyEPQSlot;
-   }
-   else
-   {
-       lazyEPQSlotPtr = NULL;
-   }
    result = table_tuple_update(resultRelationDesc, tupleid, slot,
                                estate->es_output_cid,
                                estate->es_snapshot,
                                estate->es_crosscheck_snapshot,
                                true /* wait for commit */ ,
                                &context->tmfd, &updateCxt->lockmode,
-                               &updateCxt->updateIndexes,
-                               lazyEPQSlotPtr);
+                               &updateCxt->updateIndexes);
    if (result == TM_Ok)
        updateCxt->updated = true;
 
@@ -2269,7 +2273,7 @@ ExecCrossPartitionUpdateForeignKey(ModifyTableContext *context,
 static TupleTableSlot *
 ExecUpdate(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
           ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
-          bool canSetTag, bool locked)
+          bool canSetTag)
 {
    EState     *estate = context->estate;
    Relation    resultRelationDesc = resultRelInfo->ri_RelationDesc;
@@ -2331,8 +2335,7 @@ ExecUpdate(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
         */
 redo_act:
        result = ExecUpdateAct(context, resultRelInfo, tupleid, oldtuple, slot,
-                              canSetTag, !IsolationUsesXactSnapshot(),
-                              &updateCxt);
+                              canSetTag, &updateCxt);
 
        /*
         * If ExecUpdateAct reports that a cross-partition update was done,
@@ -2391,39 +2394,81 @@ redo_act:
                        ereport(ERROR,
                                (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
                                 errmsg("could not serialize access due to concurrent update")));
-                   Assert(!locked);
 
                    /*
-                    * ExecUpdateAct() has already locked the old tuple for
-                    * us. Now we need to copy it to the right slot.
+                    * Already know that we're going to need to do EPQ, so
+                    * fetch tuple directly into the right slot.
                     */
                    inputslot = EvalPlanQualSlot(context->epqstate, resultRelationDesc,
                                                 resultRelInfo->ri_RangeTableIndex);
 
-                   /* Make sure ri_oldTupleSlot is initialized. */
-                   if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
-                       ExecInitUpdateProjection(context->mtstate,
-                                                resultRelInfo);
+                   result = table_tuple_lock(resultRelationDesc, tupleid,
+                                             estate->es_snapshot,
+                                             inputslot, estate->es_output_cid,
+                                             updateCxt.lockmode, LockWaitBlock,
+                                             TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
+                                             &context->tmfd);
+
+                   switch (result)
+                   {
+                       case TM_Ok:
+                           Assert(context->tmfd.traversed);
+
+                           /* Make sure ri_oldTupleSlot is initialized. */
+                           if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
+                               ExecInitUpdateProjection(context->mtstate,
+                                                        resultRelInfo);
 
-                   /*
-                    * Save the locked tuple for further calculation of the
-                    * new tuple.
-                    */
-                   oldSlot = resultRelInfo->ri_oldTupleSlot;
-                   ExecCopySlot(oldSlot, inputslot);
-                   ExecMaterializeSlot(oldSlot);
-                   Assert(context->tmfd.traversed);
-
-                   epqslot = EvalPlanQual(context->epqstate,
-                                          resultRelationDesc,
-                                          resultRelInfo->ri_RangeTableIndex,
-                                          inputslot);
-                   if (TupIsNull(epqslot))
-                       /* Tuple not passing quals anymore, exiting... */
-                       return NULL;
-                   slot = ExecGetUpdateNewTuple(resultRelInfo,
-                                                epqslot, oldSlot);
-                   goto redo_act;
+                           /*
+                            * Save the locked tuple for further calculation
+                            * of the new tuple.
+                            */
+                           oldSlot = resultRelInfo->ri_oldTupleSlot;
+                           ExecCopySlot(oldSlot, inputslot);
+                           ExecMaterializeSlot(oldSlot);
+
+                           epqslot = EvalPlanQual(context->epqstate,
+                                                  resultRelationDesc,
+                                                  resultRelInfo->ri_RangeTableIndex,
+                                                  inputslot);
+                           if (TupIsNull(epqslot))
+                               /* Tuple not passing quals anymore, exiting... */
+                               return NULL;
+
+                           slot = ExecGetUpdateNewTuple(resultRelInfo,
+                                                        epqslot, oldSlot);
+                           goto redo_act;
+
+                       case TM_Deleted:
+                           /* tuple already deleted; nothing to do */
+                           return NULL;
+
+                       case TM_SelfModified:
+
+                           /*
+                            * This can be reached when following an update
+                            * chain from a tuple updated by another session,
+                            * reaching a tuple that was already updated in
+                            * this transaction. If previously modified by
+                            * this command, ignore the redundant update,
+                            * otherwise error out.
+                            *
+                            * See also TM_SelfModified response to
+                            * table_tuple_update() above.
+                            */
+                           if (context->tmfd.cmax != estate->es_output_cid)
+                               ereport(ERROR,
+                                       (errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
+                                        errmsg("tuple to be updated was already modified by an operation triggered by the current command"),
+                                        errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
+                           return NULL;
+
+                       default:
+                           /* see table_tuple_lock call in ExecDelete() */
+                           elog(ERROR, "unexpected table_tuple_lock status: %u",
+                                result);
+                           return NULL;
+                   }
                }
 
                break;
@@ -2665,7 +2710,7 @@ ExecOnConflictUpdate(ModifyTableContext *context,
    *returning = ExecUpdate(context, resultRelInfo,
                            conflictTid, NULL,
                            resultRelInfo->ri_onConflict->oc_ProjSlot,
-                           canSetTag, true);
+                           canSetTag);
 
    /*
     * Clear out existing tuple, as there might not be another conflict among
@@ -2868,7 +2913,7 @@ lmerge_matched:
                    break;      /* concurrent update/delete */
                }
                result = ExecUpdateAct(context, resultRelInfo, tupleid, NULL,
-                                      newslot, false, false, &updateCxt);
+                                      newslot, false, &updateCxt);
                if (result == TM_Ok && updateCxt.updated)
                {
                    ExecUpdateEpilogue(context, &updateCxt, resultRelInfo,
@@ -2886,8 +2931,7 @@ lmerge_matched:
                        return true;    /* "do nothing" */
                    break;      /* concurrent update/delete */
                }
-               result = ExecDeleteAct(context, resultRelInfo, tupleid,
-                                      false, false);
+               result = ExecDeleteAct(context, resultRelInfo, tupleid, false);
                if (result == TM_Ok)
                {
                    ExecDeleteEpilogue(context, resultRelInfo, tupleid, NULL,
@@ -3793,7 +3837,7 @@ ExecModifyTable(PlanState *pstate)
 
                /* Now apply the update. */
                slot = ExecUpdate(&context, resultRelInfo, tupleid, oldtuple,
-                                 slot, node->canSetTag, false);
+                                 slot, node->canSetTag);
                break;
 
            case CMD_DELETE:
index 7159365e6528977617e540a3640efe90d35e9c74..50ae053f461741b1fe84ad6b1768c6bf6df100cf 100644 (file)
@@ -530,8 +530,7 @@ typedef struct TableAmRoutine
                                 Snapshot crosscheck,
                                 bool wait,
                                 TM_FailureData *tmfd,
-                                bool changingPart,
-                                LazyTupleTableSlot *lockedSlot);
+                                bool changingPart);
 
    /* see table_tuple_update() for reference about parameters */
    TM_Result   (*tuple_update) (Relation rel,
@@ -543,8 +542,7 @@ typedef struct TableAmRoutine
                                 bool wait,
                                 TM_FailureData *tmfd,
                                 LockTupleMode *lockmode,
-                                TU_UpdateIndexes *update_indexes,
-                                LazyTupleTableSlot *lockedSlot);
+                                TU_UpdateIndexes *update_indexes);
 
    /* see table_tuple_lock() for reference about parameters */
    TM_Result   (*tuple_lock) (Relation rel,
@@ -1459,7 +1457,7 @@ table_multi_insert(Relation rel, TupleTableSlot **slots, int nslots,
 }
 
 /*
- * Delete a tuple (or lock last tuple version if lockedSlot is given).
+ * Delete a tuple.
  *
  * NB: do not call this directly unless prepared to deal with
  * concurrent-update conditions.  Use simple_table_tuple_delete instead.
@@ -1475,8 +1473,6 @@ table_multi_insert(Relation rel, TupleTableSlot **slots, int nslots,
  * tmfd - filled in failure cases (see below)
  * changingPart - true iff the tuple is being moved to another partition
  *     table due to an update of the partition key. Otherwise, false.
- * lockedSlot - lazy slot to save the locked tuple if should lock the last
- *     row version during the concurrent update. NULL if not needed.
  *
  * Normal, successful return value is TM_Ok, which means we did actually
  * delete it.  Failure return codes are TM_SelfModified, TM_Updated, and
@@ -1489,17 +1485,15 @@ table_multi_insert(Relation rel, TupleTableSlot **slots, int nslots,
 static inline TM_Result
 table_tuple_delete(Relation rel, ItemPointer tid, CommandId cid,
                   Snapshot snapshot, Snapshot crosscheck, bool wait,
-                  TM_FailureData *tmfd, bool changingPart,
-                  LazyTupleTableSlot *lockedSlot)
+                  TM_FailureData *tmfd, bool changingPart)
 {
    return rel->rd_tableam->tuple_delete(rel, tid, cid,
                                         snapshot, crosscheck,
-                                        wait, tmfd, changingPart,
-                                        lockedSlot);
+                                        wait, tmfd, changingPart);
 }
 
 /*
- * Update a tuple (or lock last tuple version if lockedSlot is given).
+ * Update a tuple.
  *
  * NB: do not call this directly unless you are prepared to deal with
  * concurrent-update conditions.  Use simple_table_tuple_update instead.
@@ -1517,9 +1511,7 @@ table_tuple_delete(Relation rel, ItemPointer tid, CommandId cid,
  * lockmode - filled with lock mode acquired on tuple
  *  update_indexes - in success cases this is set to true if new index entries
  *     are required for this tuple
- *     lockedSlot - lazy slot to save the locked tuple if should lock the last
- *     row version during the concurrent update. NULL if not needed.
-
+ *
  * Normal, successful return value is TM_Ok, which means we did actually
  * update it.  Failure return codes are TM_SelfModified, TM_Updated, and
  * TM_BeingModified (the last only possible if wait == false).
@@ -1538,14 +1530,12 @@ static inline TM_Result
 table_tuple_update(Relation rel, ItemPointer otid, TupleTableSlot *slot,
                   CommandId cid, Snapshot snapshot, Snapshot crosscheck,
                   bool wait, TM_FailureData *tmfd, LockTupleMode *lockmode,
-                  TU_UpdateIndexes *update_indexes,
-                  LazyTupleTableSlot *lockedSlot)
+                  TU_UpdateIndexes *update_indexes)
 {
    return rel->rd_tableam->tuple_update(rel, otid, slot,
                                         cid, snapshot, crosscheck,
                                         wait, tmfd,
-                                        lockmode, update_indexes,
-                                        lockedSlot);
+                                        lockmode, update_indexes);
 }
 
 /*
index 2e13ecc3ffea9192b8b168d1251aa7f4cbcd3e90..ff64b7cb98fe082874ff150afc187656e4a59795 100644 (file)
@@ -300,44 +300,6 @@ typedef struct MinimalTupleTableSlot
 #define TupIsNull(slot) \
    ((slot) == NULL || TTS_EMPTY(slot))
 
-/*----------
- * LazyTupleTableSlot -- a lazy version of TupleTableSlot.
- *
- * Sometimes caller might need to pass to the function a slot, which most
- * likely will reain undemanded.  Preallocating such slot would be a waste of
- * resources in the  majority of cases.  Lazy slot is aimed to resolve this
- * problem.  It is basically a promise to allocate the slot once it's needed.
- * Once callee needs the slot, it could get it using LAZY_TTS_EVAL(lazySlot)
- * macro.
- */
-typedef struct
-{
-   TupleTableSlot *slot;       /* cached slot or NULL if not yet allocated */
-   TupleTableSlot *(*getSlot) (void *arg); /* callback for slot allocation */
-   void       *getSlotArg;     /* argument for the callback above */
-} LazyTupleTableSlot;
-
-/*
- * A constructor for the lazy slot.
- */
-#define MAKE_LAZY_TTS(lazySlot, callback, arg) \
-   do { \
-       (lazySlot)->slot = NULL; \
-       (lazySlot)->getSlot = callback; \
-       (lazySlot)->getSlotArg = arg; \
-   } while (false)
-
-/*
- * Macro for lazy slot evaluation.  NULL lazy slot evaluates to NULL slot.
- * Cached version is used if present.  Use the callback otherwise.
- */
-#define LAZY_TTS_EVAL(lazySlot) \
-   ((lazySlot) ? \
-       ((lazySlot)->slot ? \
-           (lazySlot)->slot : \
-           ((lazySlot)->slot = (lazySlot)->getSlot((lazySlot)->getSlotArg))) : \
-       NULL)
-
 /* in executor/execTuples.c */
 extern TupleTableSlot *MakeTupleTableSlot(TupleDesc tupleDesc,
                                          const TupleTableSlotOps *tts_ops);
index b97174d160794c1208ee006daef5fc8d354ba260..5c0410869f739308d3c4848d1515328f833328ba 100644 (file)
@@ -956,7 +956,6 @@ GenerationPointer
 GenericCosts
 GenericXLogState
 GeqoPrivateData
-GetEPQSlotArg
 GetForeignJoinPaths_function
 GetForeignModifyBatchSize_function
 GetForeignPaths_function
@@ -1402,7 +1401,6 @@ LagTracker
 LargeObjectDesc
 LastAttnumInfo
 Latch
-LazyTupleTableSlot
 LerpFunc
 LexDescr
 LexemeEntry