Revert "Rewrite some RI code to avoid using SPI"

This reverts commit 99392cd.
We'd rather rewrite ri_triggers.c as a whole rather than piecemeal.

Discussion: https://postgr.es/m/E1ncXX2-000mFt-Pe@gemulon.postgresql.org

Author: alvherre

src/backend/executor/execPartition.c

@@ -176,9 +176,8 @@ static void FormPartitionKeyDatum(PartitionDispatch pd,
 								  EState *estate,
 								  Datum *values,
 								  bool *isnull);
-static int	get_partition_for_tuple(PartitionKey key,
-									PartitionDesc partdesc,
-									Datum *values, bool *isnull);
+static int	get_partition_for_tuple(PartitionDispatch pd, Datum *values,
+									bool *isnull);
 static char *ExecBuildSlotPartitionKeyDescription(Relation rel,
 												  Datum *values,
 												  bool *isnull,
@@ -319,9 +318,7 @@ ExecFindPartition(ModifyTableState *mtstate,
 		 * these values, error out.
 		 */
 		if (partdesc->nparts == 0 ||
-			(partidx = get_partition_for_tuple(dispatch->key,
-											   dispatch->partdesc,
-											   values, isnull)) < 0)
+			(partidx = get_partition_for_tuple(dispatch, values, isnull)) < 0)
 		{
 			char	   *val_desc;
 
@@ -1344,12 +1341,12 @@ FormPartitionKeyDatum(PartitionDispatch pd,
  * found or -1 if none found.
  */
 static int
-get_partition_for_tuple(PartitionKey key,
-						PartitionDesc partdesc,
-						Datum *values, bool *isnull)
+get_partition_for_tuple(PartitionDispatch pd, Datum *values, bool *isnull)
 {
 	int			bound_offset;
 	int			part_index = -1;
+	PartitionKey key = pd->key;
+	PartitionDesc partdesc = pd->partdesc;
 	PartitionBoundInfo boundinfo = partdesc->boundinfo;
 
 	/* Route as appropriate based on partitioning strategy. */
@@ -1441,165 +1438,6 @@ get_partition_for_tuple(PartitionKey key,
 	return part_index;
 }
 
-/*
- * ExecGetLeafPartitionForKey
- *		Finds the leaf partition of partitioned table 'root_rel' that would
- *		contain the specified key tuple.
- *
- * A subset of the table's columns (including all of the partition key columns)
- * must be specified:
- * - 'key_natts' indicats the number of columns contained in the key
- * - 'key_attnums' indicates their attribute numbers as defined in 'root_rel'
- * - 'key_vals' and 'key_nulls' specify the key tuple
- *
- * Returns the leaf partition, locked with the given lockmode, or NULL if
- * there isn't one.  Caller is responsibly for closing it.  All intermediate
- * partitions are also locked with the same lockmode.  Caller must have locked
- * the root already.
- *
- * In addition, the OID of the index of a unique constraint on the root table
- * must be given as 'root_idxoid'; *leaf_idxoid will be set to the OID of the
- * corresponding index on the returned leaf partition.  (This can be used by
- * caller to search for a tuple matching the key in the leaf partition.)
- *
- * This works because the unique key defined on the root relation is required
- * to contain the partition key columns of all of the ancestors that lead up to
- * a given leaf partition.
- */
-Relation
-ExecGetLeafPartitionForKey(Relation root_rel, int key_natts,
-						   const AttrNumber *key_attnums,
-						   Datum *key_vals, char *key_nulls,
-						   Oid root_idxoid, int lockmode,
-						   Oid *leaf_idxoid)
-{
-	Relation	found_leafpart = NULL;
-	Relation	rel = root_rel;
-	Oid			constr_idxoid = root_idxoid;
-	PartitionDirectory partdir;
-
-	Assert(root_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
-
-	*leaf_idxoid = InvalidOid;
-
-	partdir = CreatePartitionDirectory(CurrentMemoryContext, true);
-
-	/*
-	 * Descend through partitioned parents to find the leaf partition that
-	 * would accept a row with the provided key values, starting with the root
-	 * parent.
-	 */
-	for (;;)
-	{
-		PartitionKey partkey = RelationGetPartitionKey(rel);
-		PartitionDesc partdesc;
-		Datum		partkey_vals[PARTITION_MAX_KEYS];
-		bool		partkey_isnull[PARTITION_MAX_KEYS];
-		AttrNumber *root_partattrs = partkey->partattrs;
-		int			found_att;
-		int			partidx;
-		Oid			partoid;
-
-		CHECK_FOR_INTERRUPTS();
-
-		/*
-		 * Collect partition key values from the unique key.
-		 *
-		 * Because we only have the root table's copy of pk_attnums, must map
-		 * any non-root table's partition key attribute numbers to the root
-		 * table's.
-		 */
-		if (rel != root_rel)
-		{
-			/*
-			 * map->attnums will contain root table attribute numbers for each
-			 * attribute of the current partitioned relation.
-			 */
-			AttrMap    *map;
-
-			map = build_attrmap_by_name_if_req(RelationGetDescr(root_rel),
-											   RelationGetDescr(rel));
-			if (map)
-			{
-				root_partattrs = palloc(partkey->partnatts *
-										sizeof(AttrNumber));
-				for (int att = 0; att < partkey->partnatts; att++)
-				{
-					AttrNumber	partattno = partkey->partattrs[att];
-
-					root_partattrs[att] = map->attnums[partattno - 1];
-				}
-
-				free_attrmap(map);
-			}
-		}
-
-		/*
-		 * Map the values/isnulls to match the partition description, as
-		 * necessary.
-		 *
-		 * (Referenced key specification does not allow expressions, so there
-		 * would not be expressions in the partition keys either.)
-		 */
-		Assert(partkey->partexprs == NIL);
-		found_att = 0;
-		for (int keyatt = 0; keyatt < key_natts; keyatt++)
-		{
-			for (int att = 0; att < partkey->partnatts; att++)
-			{
-				if (root_partattrs[att] == key_attnums[keyatt])
-				{
-					partkey_vals[found_att] = key_vals[keyatt];
-					partkey_isnull[found_att] = (key_nulls[keyatt] == 'n');
-					found_att++;
-					break;
-				}
-			}
-		}
-		/* We had better have found values for all partition keys */
-		Assert(found_att == partkey->partnatts);
-
-		if (root_partattrs != partkey->partattrs)
-			pfree(root_partattrs);
-
-		/* Get the PartitionDesc using the partition directory machinery.  */
-		partdesc = PartitionDirectoryLookup(partdir, rel);
-		if (partdesc->nparts == 0)
-			break;
-
-		/* Find the partition for the key. */
-		partidx = get_partition_for_tuple(partkey, partdesc,
-										  partkey_vals, partkey_isnull);
-		Assert(partidx < 0 || partidx < partdesc->nparts);
-
-		/* close the previous parent if any, but keep lock */
-		if (rel != root_rel)
-			table_close(rel, NoLock);
-
-		/* No partition found. */
-		if (partidx < 0)
-			break;
-
-		partoid = partdesc->oids[partidx];
-		rel = table_open(partoid, lockmode);
-		constr_idxoid = index_get_partition(rel, constr_idxoid);
-
-		/*
-		 * We're done if the partition is a leaf, else find its partition in
-		 * the next iteration.
-		 */
-		if (partdesc->is_leaf[partidx])
-		{
-			*leaf_idxoid = constr_idxoid;
-			found_leafpart = rel;
-			break;
-		}
-	}
-
-	DestroyPartitionDirectory(partdir);
-	return found_leafpart;
-}
-
 /*
  * ExecBuildSlotPartitionKeyDescription
  *

src/backend/executor/nodeLockRows.c

@@ -79,7 +79,10 @@ ExecLockRows(PlanState *pstate)
 		Datum		datum;
 		bool		isNull;
 		ItemPointerData tid;
+		TM_FailureData tmfd;
 		LockTupleMode lockmode;
+		int			lockflags = 0;
+		TM_Result	test;
 		TupleTableSlot *markSlot;
 
 		/* clear any leftover test tuple for this rel */
@@ -176,11 +179,74 @@ ExecLockRows(PlanState *pstate)
 				break;
 		}
 
-		/* skip tuple if it couldn't be locked */
-		if (!ExecLockTableTuple(erm->relation, &tid, markSlot,
-								estate->es_snapshot, estate->es_output_cid,
-								lockmode, erm->waitPolicy, &epq_needed))
-			goto lnext;
+		lockflags = TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS;
+		if (!IsolationUsesXactSnapshot())
+			lockflags |= TUPLE_LOCK_FLAG_FIND_LAST_VERSION;
+
+		test = table_tuple_lock(erm->relation, &tid, estate->es_snapshot,
+								markSlot, estate->es_output_cid,
+								lockmode, erm->waitPolicy,
+								lockflags,
+								&tmfd);
+
+		switch (test)
+		{
+			case TM_WouldBlock:
+				/* couldn't lock tuple in SKIP LOCKED mode */
+				goto lnext;
+
+			case TM_SelfModified:
+
+				/*
+				 * The target tuple was already updated or deleted by the
+				 * current command, or by a later command in the current
+				 * transaction.  We *must* ignore the tuple in the former
+				 * case, so as to avoid the "Halloween problem" of repeated
+				 * update attempts.  In the latter case it might be sensible
+				 * to fetch the updated tuple instead, but doing so would
+				 * require changing heap_update and heap_delete to not
+				 * complain about updating "invisible" tuples, which seems
+				 * pretty scary (table_tuple_lock will not complain, but few
+				 * callers expect TM_Invisible, and we're not one of them). So
+				 * for now, treat the tuple as deleted and do not process.
+				 */
+				goto lnext;
+
+			case TM_Ok:
+
+				/*
+				 * Got the lock successfully, the locked tuple saved in
+				 * markSlot for, if needed, EvalPlanQual testing below.
+				 */
+				if (tmfd.traversed)
+					epq_needed = true;
+				break;
+
+			case TM_Updated:
+				if (IsolationUsesXactSnapshot())
+					ereport(ERROR,
+							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+							 errmsg("could not serialize access due to concurrent update")));
+				elog(ERROR, "unexpected table_tuple_lock status: %u",
+					 test);
+				break;
+
+			case TM_Deleted:
+				if (IsolationUsesXactSnapshot())
+					ereport(ERROR,
+							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+							 errmsg("could not serialize access due to concurrent update")));
+				/* tuple was deleted so don't return it */
+				goto lnext;
+
+			case TM_Invisible:
+				elog(ERROR, "attempted to lock invisible tuple");
+				break;
+
+			default:
+				elog(ERROR, "unrecognized table_tuple_lock status: %u",
+					 test);
+		}
 
 		/* Remember locked tuple's TID for EPQ testing and WHERE CURRENT OF */
 		erm->curCtid = tid;
@@ -215,91 +281,6 @@ ExecLockRows(PlanState *pstate)
 	return slot;
 }
 
-/*
- * ExecLockTableTuple
- * 		Locks tuple with the specified TID in lockmode following given wait
- * 		policy
- *
- * Returns true if the tuple was successfully locked.  Locked tuple is loaded
- * into provided slot.
- */
-bool
-ExecLockTableTuple(Relation relation, ItemPointer tid, TupleTableSlot *slot,
-				   Snapshot snapshot, CommandId cid,
-				   LockTupleMode lockmode, LockWaitPolicy waitPolicy,
-				   bool *epq_needed)
-{
-	TM_FailureData tmfd;
-	int			lockflags = TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS;
-	TM_Result	test;
-
-	if (!IsolationUsesXactSnapshot())
-		lockflags |= TUPLE_LOCK_FLAG_FIND_LAST_VERSION;
-
-	test = table_tuple_lock(relation, tid, snapshot, slot, cid, lockmode,
-							waitPolicy, lockflags, &tmfd);
-
-	switch (test)
-	{
-		case TM_WouldBlock:
-			/* couldn't lock tuple in SKIP LOCKED mode */
-			return false;
-
-		case TM_SelfModified:
-
-			/*
-			 * The target tuple was already updated or deleted by the current
-			 * command, or by a later command in the current transaction.  We
-			 * *must* ignore the tuple in the former case, so as to avoid the
-			 * "Halloween problem" of repeated update attempts.  In the latter
-			 * case it might be sensible to fetch the updated tuple instead,
-			 * but doing so would require changing heap_update and heap_delete
-			 * to not complain about updating "invisible" tuples, which seems
-			 * pretty scary (table_tuple_lock will not complain, but few
-			 * callers expect TM_Invisible, and we're not one of them). So for
-			 * now, treat the tuple as deleted and do not process.
-			 */
-			return false;
-
-		case TM_Ok:
-
-			/*
-			 * Got the lock successfully, the locked tuple saved in slot for
-			 * EvalPlanQual, if asked by the caller.
-			 */
-			if (tmfd.traversed && epq_needed)
-				*epq_needed = true;
-			break;
-
-		case TM_Updated:
-			if (IsolationUsesXactSnapshot())
-				ereport(ERROR,
-						(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
-						 errmsg("could not serialize access due to concurrent update")));
-			elog(ERROR, "unexpected table_tuple_lock status: %u",
-				 test);
-			break;
-
-		case TM_Deleted:
-			if (IsolationUsesXactSnapshot())
-				ereport(ERROR,
-						(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
-						 errmsg("could not serialize access due to concurrent update")));
-			/* tuple was deleted so don't return it */
-			return false;
-
-		case TM_Invisible:
-			elog(ERROR, "attempted to lock invisible tuple");
-			return false;
-
-		default:
-			elog(ERROR, "unrecognized table_tuple_lock status: %u", test);
-			return false;
-	}
-
-	return true;
-}
-
 /* ----------------------------------------------------------------
  *		ExecInitLockRows
  *