Revert "[6X_STABLE] Fix bug: PLPY function causes master process rese…

…t. (#16864)"

This reverts commit 45d6ba8.

src/backend/access/transam/xact.c

@@ -5043,7 +5043,6 @@ void
 BeginInternalSubTransaction(char *name)
 {
 	TransactionState s = CurrentTransactionState;
-	SIMPLE_FAULT_INJECTOR("begin_internal_sub_transaction");
 
 	if (Gp_role == GP_ROLE_DISPATCH)
 	{

src/pl/plpython/expected/plpython_subtransaction.out

@@ -476,48 +476,3 @@ CONTEXT:  Traceback (most recent call last):
   PL/Python function "cursor_close_aborted_subxact", line 7, in <module>
     cur.close()
 PL/Python function "cursor_close_aborted_subxact"
--- error report test in subtransaction begin
--- prepare function
-CREATE OR REPLACE FUNCTION test_func() RETURNS SETOF int AS
-$$
-plpy.execute("select pg_backend_pid()")
-
-for i in range(0, 5):
-    yield (i)
-
-$$ LANGUAGE plpython3u;
--- inject fault and wait for trigger
-select gp_inject_fault_infinite('begin_internal_sub_transaction', 'error', 1);
- gp_inject_fault_infinite 
---------------------------
- Success:
-(1 row)
-
-SELECT test_func();
-ERROR:  function "test_func" error fetching next item from iterator
-DETAIL:  spiexceptions.FaultInject: fault triggered, fault name:'begin_internal_sub_transaction' fault type:'error'
-CONTEXT:  Traceback (most recent call last):
-PL/Python function "test_func"
-select gp_wait_until_triggered_fault('begin_internal_sub_transaction', 1, 1);
- gp_wait_until_triggered_fault 
--------------------------------
- Success:
-(1 row)
-
-select gp_inject_fault('begin_internal_sub_transaction', 'reset', 1);
- gp_inject_fault 
------------------
- Success:
-(1 row)
-
-SELECT test_func();
- test_func 
------------
-         0
-         1
-         2
-         3
-         4
-(5 rows)
-
-DROP FUNCTION test_func();

src/pl/plpython/plpy_cursorobject.c

@@ -116,8 +116,7 @@ PLy_cursor_query(const char *query)
 	oldcontext = CurrentMemoryContext;
 	oldowner = CurrentResourceOwner;
 
-	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
-		return NULL;
+	PLy_spi_subtransaction_begin(oldcontext, oldowner);
 
 	PG_TRY();
 	{
@@ -206,8 +205,7 @@ PLy_cursor_plan(PyObject *ob, PyObject *args)
 	oldcontext = CurrentMemoryContext;
 	oldowner = CurrentResourceOwner;
 
-	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
-		return NULL;
+	PLy_spi_subtransaction_begin(oldcontext, oldowner);
 
 	PG_TRY();
 	{
@@ -355,8 +353,7 @@ PLy_cursor_iternext(PyObject *self)
 	oldcontext = CurrentMemoryContext;
 	oldowner = CurrentResourceOwner;
 
-	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
-		return NULL;
+	PLy_spi_subtransaction_begin(oldcontext, oldowner);
 
 	PG_TRY();
 	{
@@ -425,8 +422,7 @@ PLy_cursor_fetch(PyObject *self, PyObject *args)
 	oldcontext = CurrentMemoryContext;
 	oldowner = CurrentResourceOwner;
 
-	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
-		return NULL;
+	PLy_spi_subtransaction_begin(oldcontext, oldowner);
 
 	PG_TRY();
 	{

src/pl/plpython/plpy_spi.c

@@ -78,8 +78,7 @@ PLy_spi_prepare(PyObject *self, PyObject *args)
 	oldcontext = CurrentMemoryContext;
 	oldowner = CurrentResourceOwner;
 
-	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
-		return NULL;
+	PLy_spi_subtransaction_begin(oldcontext, oldowner);
 
 	PG_TRY();
 	{
@@ -255,8 +254,7 @@ PLy_spi_execute_plan(PyObject *ob, PyObject *list, int64 limit)
 	oldcontext = CurrentMemoryContext;
 	oldowner = CurrentResourceOwner;
 
-	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
-		return NULL;
+	PLy_spi_subtransaction_begin(oldcontext, oldowner);
 
 	PG_TRY();
 	{
@@ -369,8 +367,7 @@ PLy_spi_execute_query(char *query, int64 limit)
 	oldcontext = CurrentMemoryContext;
 	oldowner = CurrentResourceOwner;
 
-	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
-		return NULL;
+	PLy_spi_subtransaction_begin(oldcontext, oldowner);
 
 	PG_TRY();
 	{
@@ -501,9 +498,7 @@ PLy_spi_execute_fetch_result(SPITupleTable *tuptable, int64 rows, int status)
  *	MemoryContext oldcontext = CurrentMemoryContext;
  *	ResourceOwner oldowner = CurrentResourceOwner;
  *
- *	if(!PLy_spi_subtransaction_begin(oldcontext, oldowner))
- *		return NULL;
- *	
+ *	PLy_spi_subtransaction_begin(oldcontext, oldowner);
  *	PG_TRY();
  *	{
  *		<call SPI functions>
@@ -520,48 +515,12 @@ PLy_spi_execute_fetch_result(SPITupleTable *tuptable, int64 rows, int status)
  * These utilities take care of restoring connection to the SPI manager and
  * setting a Python exception in case of an abort.
  */
-bool
+void
 PLy_spi_subtransaction_begin(MemoryContext oldcontext, ResourceOwner oldowner)
 {
-	PG_TRY();
-	{
-		/* Start subtransaction (could fail) */
-		BeginInternalSubTransaction(NULL);
-		/* Want to run inside function's memory context */
-		MemoryContextSwitchTo(oldcontext);
-	}
-	PG_CATCH();
-	{
-		ErrorData *edata;
-		PLyExceptionEntry *entry;
-		PyObject *exc;
-
-		/* Ensure we restore original context and owner */
-		MemoryContextSwitchTo(oldcontext);
-		CurrentResourceOwner = oldowner;
-
-		/* Save error info */
-		edata = CopyErrorData();
-		FlushErrorState();
-
-		/* Look up the correct exception */
-		entry = hash_search(PLy_spi_exceptions, &(edata->sqlerrcode),
-							HASH_FIND, NULL);
-
-		/*
-		 * This could be a custom error code, if that's the case fallback to
-		 * SPIError
-		 */
-		exc = entry ? entry->exc : PLy_exc_spi_error;
-		/* Make Python raise the exception */
-		PLy_spi_exception_set(exc, edata);
-		FreeErrorData(edata);
-
-		return false;
-	}
-	PG_END_TRY();
-
-	return true;
+	BeginInternalSubTransaction(NULL);
+	/* Want to run inside function's memory context */
+	MemoryContextSwitchTo(oldcontext);
 }
 
 void

src/pl/plpython/plpy_spi.h

@@ -18,7 +18,7 @@ typedef struct PLyExceptionEntry
 } PLyExceptionEntry;
 
 /* handling of SPI operations inside subtransactions */
-extern bool PLy_spi_subtransaction_begin(MemoryContext oldcontext, ResourceOwner oldowner);
+extern void PLy_spi_subtransaction_begin(MemoryContext oldcontext, ResourceOwner oldowner);
 extern void PLy_spi_subtransaction_commit(MemoryContext oldcontext, ResourceOwner oldowner);
 extern void PLy_spi_subtransaction_abort(MemoryContext oldcontext, ResourceOwner oldowner);
 

src/pl/plpython/sql/plpython_subtransaction.sql

@@ -294,24 +294,3 @@ SELECT cursor_in_subxact();
 SELECT cursor_aborted_subxact();
 SELECT cursor_plan_aborted_subxact();
 SELECT cursor_close_aborted_subxact();
-
--- error report test in subtransaction begin
--- prepare function
-CREATE OR REPLACE FUNCTION test_func() RETURNS SETOF int AS
-$$
-plpy.execute("select pg_backend_pid()")
-
-for i in range(0, 5):
-    yield (i)
-
-$$ LANGUAGE plpythonu;
-
--- inject fault and wait for trigger
-select gp_inject_fault_infinite('begin_internal_sub_transaction', 'error', 1);
-SELECT test_func();
-select gp_wait_until_triggered_fault('begin_internal_sub_transaction', 1, 1);
-select gp_inject_fault('begin_internal_sub_transaction', 'reset', 1);
-
-SELECT test_func();
-
-DROP FUNCTION test_func();