Simplify reindex_relation's API.

For what seem entirely historical reasons, a bitmask "flags" argument was
recently added to reindex_relation without subsuming its existing boolean
argument into that bitmask.  This seems a bit bizarre, so fold them
together.

Author: tglsfdc

src/backend/catalog/index.c

@@ -2841,29 +2841,33 @@ reindex_index(Oid indexId, bool skip_constraint_checks)
  * reindex_relation - This routine is used to recreate all indexes
  * of a relation (and optionally its toast relation too, if any).
  *
- * "flags" can include REINDEX_SUPPRESS_INDEX_USE and REINDEX_CHECK_CONSTRAINTS.
+ * "flags" is a bitmask that can include any combination of these bits:
  *
- * If flags has REINDEX_SUPPRESS_INDEX_USE, the relation was just completely
+ * REINDEX_REL_PROCESS_TOAST: if true, process the toast table too (if any).
+ *
+ * REINDEX_REL_SUPPRESS_INDEX_USE: if true, the relation was just completely
  * rebuilt by an operation such as VACUUM FULL or CLUSTER, and therefore its
  * indexes are inconsistent with it.  This makes things tricky if the relation
  * is a system catalog that we might consult during the reindexing.  To deal
  * with that case, we mark all of the indexes as pending rebuild so that they
  * won't be trusted until rebuilt.  The caller is required to call us *without*
- * having made the rebuilt versions visible by doing CommandCounterIncrement;
+ * having made the rebuilt table visible by doing CommandCounterIncrement;
  * we'll do CCI after having collected the index list.  (This way we can still
  * use catalog indexes while collecting the list.)
  *
- * To avoid deadlocks, VACUUM FULL or CLUSTER on a system catalog must omit the
- * REINDEX_CHECK_CONSTRAINTS flag.	REINDEX should be used to rebuild an index
- * if constraint inconsistency is suspected.  For optimal performance, other
- * callers should include the flag only after transforming the data in a manner
- * that risks a change in constraint validity.
+ * REINDEX_REL_CHECK_CONSTRAINTS: if true, recheck unique and exclusion
+ * constraint conditions, else don't.  To avoid deadlocks, VACUUM FULL or
+ * CLUSTER on a system catalog must omit this flag.  REINDEX should be used to
+ * rebuild an index if constraint inconsistency is suspected.  For optimal
+ * performance, other callers should include the flag only after transforming
+ * the data in a manner that risks a change in constraint validity.
  *
- * Returns true if any indexes were rebuilt.  Note that a
- * CommandCounterIncrement will occur after each index rebuild.
+ * Returns true if any indexes were rebuilt (including toast table's index
+ * when relevant).  Note that a CommandCounterIncrement will occur after each
+ * index rebuild.
  */
 bool
-reindex_relation(Oid relid, bool toast_too, int flags)
+reindex_relation(Oid relid, int flags)
 {
 	Relation	rel;
 	Oid			toast_relid;
@@ -2919,7 +2923,7 @@ reindex_relation(Oid relid, bool toast_too, int flags)
 		List	   *doneIndexes;
 		ListCell   *indexId;
 
-		if (flags & REINDEX_SUPPRESS_INDEX_USE)
+		if (flags & REINDEX_REL_SUPPRESS_INDEX_USE)
 		{
 			/* Suppress use of all the indexes until they are rebuilt */
 			SetReindexPending(indexIds);
@@ -2940,11 +2944,11 @@ reindex_relation(Oid relid, bool toast_too, int flags)
 			if (is_pg_class)
 				RelationSetIndexList(rel, doneIndexes, InvalidOid);
 
-			reindex_index(indexOid, !(flags & REINDEX_CHECK_CONSTRAINTS));
+			reindex_index(indexOid, !(flags & REINDEX_REL_CHECK_CONSTRAINTS));
 
 			CommandCounterIncrement();
 
-			if (flags & REINDEX_SUPPRESS_INDEX_USE)
+			if (flags & REINDEX_REL_SUPPRESS_INDEX_USE)
 				RemoveReindexPending(indexOid);
 
 			if (is_pg_class)
@@ -2972,12 +2976,10 @@ reindex_relation(Oid relid, bool toast_too, int flags)
 
 	/*
 	 * If the relation has a secondary toast rel, reindex that too while we
-	 * still hold the lock on the master table.  There's never a reason to
-	 * reindex the toast table right after rebuilding the heap.
+	 * still hold the lock on the master table.
 	 */
-	Assert(!(toast_too && (flags & REINDEX_SUPPRESS_INDEX_USE)));
-	if (toast_too && OidIsValid(toast_relid))
-		result |= reindex_relation(toast_relid, false, flags);
+	if ((flags & REINDEX_REL_PROCESS_TOAST) && OidIsValid(toast_relid))
+		result |= reindex_relation(toast_relid, flags);
 
 	return result;
 }

src/backend/commands/cluster.c

@@ -1399,10 +1399,10 @@ finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap,
 	 * so no chance to reclaim disk space before commit.  We do not need a
 	 * final CommandCounterIncrement() because reindex_relation does it.
 	 */
-	reindex_flags = REINDEX_SUPPRESS_INDEX_USE;
+	reindex_flags = REINDEX_REL_SUPPRESS_INDEX_USE;
 	if (check_constraints)
-		reindex_flags |= REINDEX_CHECK_CONSTRAINTS;
-	reindex_relation(OIDOldHeap, false, reindex_flags);
+		reindex_flags |= REINDEX_REL_CHECK_CONSTRAINTS;
+	reindex_relation(OIDOldHeap, reindex_flags);
 
 	/* Destroy new heap with old filenode */
 	object.classId = RelationRelationId;

src/backend/commands/indexcmds.c

@@ -1566,7 +1566,7 @@ ReindexTable(RangeVar *relation)
 
 	ReleaseSysCache(tuple);
 
-	if (!reindex_relation(heapOid, true, 0))
+	if (!reindex_relation(heapOid, REINDEX_REL_PROCESS_TOAST))
 		ereport(NOTICE,
 				(errmsg("table \"%s\" has no indexes",
 						relation->relname)));
@@ -1679,7 +1679,7 @@ ReindexDatabase(const char *databaseName, bool do_system, bool do_user)
 		StartTransactionCommand();
 		/* functions in indexes may want a snapshot set */
 		PushActiveSnapshot(GetTransactionSnapshot());
-		if (reindex_relation(relid, true, 0))
+		if (reindex_relation(relid, REINDEX_REL_PROCESS_TOAST))
 			ereport(NOTICE,
 					(errmsg("table \"%s.%s\" was reindexed",
 							get_namespace_name(get_rel_namespace(relid)),

src/backend/commands/tablecmds.c

@@ -1080,7 +1080,7 @@ ExecuteTruncate(TruncateStmt *stmt)
 			/*
 			 * Reconstruct the indexes to match, and we're done.
 			 */
-			reindex_relation(heap_relid, true, 0);
+			reindex_relation(heap_relid, REINDEX_REL_PROCESS_TOAST);
 		}
 	}
 

src/include/catalog/index.h

@@ -88,9 +88,12 @@ extern void validate_index(Oid heapId, Oid indexId, Snapshot snapshot);
 
 extern void reindex_index(Oid indexId, bool skip_constraint_checks);
 
-#define REINDEX_CHECK_CONSTRAINTS	0x1
-#define REINDEX_SUPPRESS_INDEX_USE	0x2
-extern bool reindex_relation(Oid relid, bool toast_too, int flags);
+/* Flag bits for reindex_relation(): */
+#define REINDEX_REL_PROCESS_TOAST		0x01
+#define REINDEX_REL_SUPPRESS_INDEX_USE	0x02
+#define REINDEX_REL_CHECK_CONSTRAINTS	0x04
+
+extern bool reindex_relation(Oid relid, int flags);
 
 extern bool ReindexIsProcessingHeap(Oid heapOid);
 extern bool ReindexIsProcessingIndex(Oid indexOid);