add execution params struct (#3747)

We had 9+ parameters in some of the functions related to execution.
Execution params is created to simplify this a bit so that we can set
only the fields that we are interested in and it is easier to read.

src/backend/distributed/commands/call.c

@@ -187,10 +187,15 @@ CallFuncExprRemotely(CallStmt *callStmt, DistObjectCacheEntry *procedure,
 		};
 
 		bool localExecutionSupported = true;
-		ExecuteTaskListExtended(ROW_MODIFY_NONE, list_make1(task),
-								tupleDesc, tupleStore, hasReturning,
-								MaxAdaptiveExecutorPoolSize,
-								&xactProperties, NIL, localExecutionSupported);
+		ExecutionParams *executionParams = CreateBasicExecutionParams(
+			ROW_MODIFY_NONE, list_make1(task), MaxAdaptiveExecutorPoolSize,
+			localExecutionSupported
+			);
+		executionParams->tupleStore = tupleStore;
+		executionParams->tupleDescriptor = tupleDesc;
+		executionParams->hasReturning = hasReturning;
+		executionParams->xactProperties = xactProperties;
+		ExecuteTaskListExtended(executionParams);
 
 		while (tuplestore_gettupleslot(tupleStore, true, false, slot))
 		{

src/backend/distributed/executor/adaptive_executor.c

@@ -881,13 +881,6 @@ uint64
 ExecuteTaskListOutsideTransaction(RowModifyLevel modLevel, List *taskList,
 								  int targetPoolSize, List *jobIdList)
 {
-	TupleDesc tupleDescriptor = NULL;
-	Tuplestorestate *tupleStore = NULL;
-	bool hasReturning = false;
-
-	TransactionProperties xactProperties =
-		DecideTransactionPropertiesForTaskList(modLevel, taskList, true);
-
 	/*
 	 * As we are going to run the tasks outside transaction, we shouldn't use local execution.
 	 * However, there is some problem when using local execution related to
@@ -895,9 +888,13 @@ ExecuteTaskListOutsideTransaction(RowModifyLevel modLevel, List *taskList,
 	 * coming to this path with local execution. See PR:3711
 	 */
 	bool localExecutionSupported = false;
-	return ExecuteTaskListExtended(modLevel, taskList, tupleDescriptor,
-								   tupleStore, hasReturning, targetPoolSize,
-								   &xactProperties, jobIdList, localExecutionSupported);
+	ExecutionParams *executionParams = CreateBasicExecutionParams(
+		modLevel, taskList, targetPoolSize, localExecutionSupported
+		);
+
+	executionParams->xactProperties = DecideTransactionPropertiesForTaskList(
+		modLevel, taskList, true);
+	return ExecuteTaskListExtended(executionParams);
 }
 
 
@@ -906,19 +903,15 @@ ExecuteTaskListOutsideTransaction(RowModifyLevel modLevel, List *taskList,
  * for some of the arguments.
  */
 uint64
-ExecuteTaskList(RowModifyLevel modLevel, List *taskList, int targetPoolSize, bool
-				localExecutionSupported)
+ExecuteTaskList(RowModifyLevel modLevel, List *taskList,
+				int targetPoolSize, bool localExecutionSupported)
 {
-	TupleDesc tupleDescriptor = NULL;
-	Tuplestorestate *tupleStore = NULL;
-	bool hasReturning = false;
-
-	TransactionProperties xactProperties =
-		DecideTransactionPropertiesForTaskList(modLevel, taskList, false);
-
-	return ExecuteTaskListExtended(modLevel, taskList, tupleDescriptor,
-								   tupleStore, hasReturning, targetPoolSize,
-								   &xactProperties, NIL, localExecutionSupported);
+	ExecutionParams *executionParams = CreateBasicExecutionParams(
+		modLevel, taskList, targetPoolSize, localExecutionSupported
+		);
+	executionParams->xactProperties = DecideTransactionPropertiesForTaskList(
+		modLevel, taskList, false);
+	return ExecuteTaskListExtended(executionParams);
 }
 
 
@@ -932,13 +925,18 @@ ExecuteTaskListIntoTupleStore(RowModifyLevel modLevel, List *taskList,
 							  bool hasReturning)
 {
 	int targetPoolSize = MaxAdaptiveExecutorPoolSize;
-
-	TransactionProperties xactProperties = DecideTransactionPropertiesForTaskList(
-		modLevel, taskList, false);
 	bool localExecutionSupported = true;
-	return ExecuteTaskListExtended(modLevel, taskList, tupleDescriptor,
-								   tupleStore, hasReturning, targetPoolSize,
-								   &xactProperties, NIL, localExecutionSupported);
+	ExecutionParams *executionParams = CreateBasicExecutionParams(
+		modLevel, taskList, targetPoolSize, localExecutionSupported
+		);
+
+	executionParams->xactProperties = DecideTransactionPropertiesForTaskList(
+		modLevel, taskList, false);
+	executionParams->hasReturning = hasReturning;
+	executionParams->tupleStore = tupleStore;
+	executionParams->tupleDescriptor = tupleDescriptor;
+
+	return ExecuteTaskListExtended(executionParams);
 }
 
 
@@ -947,27 +945,24 @@ ExecuteTaskListIntoTupleStore(RowModifyLevel modLevel, List *taskList,
  * runs it.
  */
 uint64
-ExecuteTaskListExtended(RowModifyLevel modLevel, List *taskList,
-						TupleDesc tupleDescriptor, Tuplestorestate *tupleStore,
-						bool hasReturning, int targetPoolSize,
-						TransactionProperties *xactProperties,
-						List *jobIdList,
-						bool localExecutionSupported)
+ExecuteTaskListExtended(ExecutionParams *executionParams)
 {
 	ParamListInfo paramListInfo = NULL;
 	uint64 locallyProcessedRows = 0;
 	List *localTaskList = NIL;
 	List *remoteTaskList = NIL;
 
-	if (localExecutionSupported && ShouldExecuteTasksLocally(taskList))
+	if (executionParams->localExecutionSupported && ShouldExecuteTasksLocally(
+			executionParams->taskList))
 	{
 		bool readOnlyPlan = false;
-		ExtractLocalAndRemoteTasks(readOnlyPlan, taskList, &localTaskList,
+		ExtractLocalAndRemoteTasks(readOnlyPlan, executionParams->taskList,
+								   &localTaskList,
 								   &remoteTaskList);
 	}
 	else
 	{
-		remoteTaskList = taskList;
+		remoteTaskList = executionParams->taskList;
 	}
 
 	/*
@@ -982,17 +977,21 @@ ExecuteTaskListExtended(RowModifyLevel modLevel, List *taskList,
 		ErrorIfTransactionAccessedPlacementsLocally();
 	}
 
-	locallyProcessedRows += ExecuteLocalTaskList(localTaskList, tupleStore);
+	locallyProcessedRows += ExecuteLocalTaskList(localTaskList,
+												 executionParams->tupleStore);
 
 	if (MultiShardConnectionType == SEQUENTIAL_CONNECTION)
 	{
-		targetPoolSize = 1;
+		executionParams->targetPoolSize = 1;
 	}
 
 	DistributedExecution *execution =
-		CreateDistributedExecution(modLevel, remoteTaskList, hasReturning, paramListInfo,
-								   tupleDescriptor, tupleStore, targetPoolSize,
-								   xactProperties, jobIdList);
+		CreateDistributedExecution(
+			executionParams->modLevel, remoteTaskList,
+			executionParams->hasReturning, paramListInfo,
+			executionParams->tupleDescriptor, executionParams->tupleStore,
+			executionParams->targetPoolSize, &executionParams->xactProperties,
+			executionParams->jobIdList);
 
 	StartDistributedExecution(execution);
 	RunDistributedExecution(execution);
@@ -1002,6 +1001,31 @@ ExecuteTaskListExtended(RowModifyLevel modLevel, List *taskList,
 }
 
 
+/*
+ * CreateBasicExecutionParams creates basic execution parameters with some common
+ * fields.
+ */
+ExecutionParams *
+CreateBasicExecutionParams(RowModifyLevel modLevel,
+						   List *taskList,
+						   int targetPoolSize,
+						   bool localExecutionSupported)
+{
+	ExecutionParams *executionParams = palloc0(sizeof(ExecutionParams));
+	executionParams->modLevel = modLevel;
+	executionParams->taskList = taskList;
+	executionParams->targetPoolSize = targetPoolSize;
+	executionParams->localExecutionSupported = localExecutionSupported;
+
+	executionParams->tupleStore = NULL;
+	executionParams->tupleDescriptor = NULL;
+	executionParams->hasReturning = false;
+	executionParams->jobIdList = NIL;
+
+	return executionParams;
+}
+
+
 /*
  * CreateDistributedExecution creates a distributed execution data structure for
  * a distributed plan.

src/backend/distributed/executor/distributed_intermediate_results.c

@@ -422,9 +422,15 @@ ExecuteSelectTasksIntoTupleStore(List *taskList, TupleDesc resultDescriptor,
 	 * query string for the local placement.
 	 */
 	bool localExecutionSupported = false;
-	ExecuteTaskListExtended(ROW_MODIFY_READONLY, taskList, resultDescriptor,
-							resultStore, hasReturning, targetPoolSize, &xactProperties,
-							NIL, localExecutionSupported);
+	ExecutionParams *executionParams = CreateBasicExecutionParams(
+		ROW_MODIFY_READONLY, taskList, targetPoolSize, localExecutionSupported
+		);
+	executionParams->tupleDescriptor = resultDescriptor;
+	executionParams->tupleStore = resultStore;
+	executionParams->xactProperties = xactProperties;
+	executionParams->hasReturning = hasReturning;
+
+	ExecuteTaskListExtended(executionParams);
 
 	return resultStore;
 }

src/include/distributed/multi_executor.h

@@ -74,13 +74,48 @@ extern void CitusExecutorRun(QueryDesc *queryDesc, ScanDirection direction, uint
 							 bool execute_once);
 extern void AdaptiveExecutorPreExecutorRun(CitusScanState *scanState);
 extern TupleTableSlot * AdaptiveExecutor(CitusScanState *scanState);
-extern uint64 ExecuteTaskListExtended(RowModifyLevel modLevel, List *taskList,
-									  TupleDesc tupleDescriptor,
-									  Tuplestorestate *tupleStore,
-									  bool hasReturning, int targetPoolSize,
-									  TransactionProperties *xactProperties,
-									  List *jobIdList,
-									  bool localExecutionSupported);
+
+/*
+ * ExecutionParams contains parameters that are used during the execution.
+ * Some of these can be the zero value if it is not needed during the execution.
+ */
+typedef struct ExecutionParams
+{
+	/* modLevel is the access level for rows.*/
+	RowModifyLevel modLevel;
+
+	/* taskList contains the tasks for the execution.*/
+	List *taskList;
+
+	/* tupleDescriptor contains the description for the result tuples.*/
+	TupleDesc tupleDescriptor;
+
+	/* tupleStore is where the results will be stored for this execution */
+	Tuplestorestate *tupleStore;
+
+	/* hasReturning is true if this execution will return some result. */
+	bool hasReturning;
+
+	/* targetPoolSize is the maximum amount of connections per worker */
+	int targetPoolSize;
+
+	/* xactProperties contains properties for transactions, such as if we should use 2pc. */
+	TransactionProperties xactProperties;
+
+	/* jobIdList contains all job ids for the execution */
+	List *jobIdList;
+
+	/* localExecutionSupported is true if we can use local execution, if it is false
+	 * local execution will not be used. */
+	bool localExecutionSupported;
+} ExecutionParams;
+
+ExecutionParams * CreateBasicExecutionParams(RowModifyLevel modLevel,
+											 List *taskList,
+											 int targetPoolSize,
+											 bool localExecutionSupported);
+
+extern uint64 ExecuteTaskListExtended(ExecutionParams *executionParams);
 extern uint64 ExecuteTaskListIntoTupleStore(RowModifyLevel modLevel, List *taskList,
 											TupleDesc tupleDescriptor,
 											Tuplestorestate *tupleStore,