Add PreCheckPointGuts function to sync replication state before start…

… of shutdown checkpoint

src/backend/access/transam/xlog.c

@@ -694,6 +694,7 @@ static void CreateEndOfRecoveryRecord(void);
 static XLogRecPtr CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn,
 												  XLogRecPtr missingContrecPtr,
 												  TimeLineID newTLI);
+static void PreCheckPointGuts(int flags);
 static void CheckPointGuts(XLogRecPtr checkPointRedo, int flags);
 static void KeepLogSeg(XLogRecPtr recptr, XLogSegNo *logSegNo);
 static XLogRecPtr XLogGetReplicationSlotMinimumLSN(void);
@@ -6684,6 +6685,11 @@ CreateCheckPoint(int flags)
 	 */
 	SyncPreCheckpoint();
 
+	/*
+	 * NEON: perform checkpiont action requiring write to the WAL before we determine the REDO pointer.
+	 */
+	PreCheckPointGuts(flags);
+
 	/*
 	 * Use a critical section to force system panic if we have trouble.
 	 */
@@ -7191,6 +7197,28 @@ CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn, XLogRecPtr pagePtr,
 	return recptr;
 }
 
+static void
+CheckPointReplicationState(void)
+{
+	CheckPointRelationMap();
+	CheckPointReplicationSlots();
+	CheckPointSnapBuild();
+	CheckPointLogicalRewriteHeap();
+	CheckPointReplicationOrigin();
+}
+
+/*
+ * NEON:  we use logical records to persist information of about slots, origins, relation map...
+ * If it is done inside shutdown checkpoint, then Postgres panics: "concurrent write-ahead log activity while database system is shutting down"
+ * So it before checkpoint REDO position is determined.
+ */
+static void
+PreCheckPointGuts(int flags)
+{
+	if (flags & CHECKPOINT_IS_SHUTDOWN)
+		CheckPointReplicationState();
+}
+
 /*
  * Flush all data in shared memory to disk, and fsync
  *
@@ -7200,18 +7228,8 @@ CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn, XLogRecPtr pagePtr,
 static void
 CheckPointGuts(XLogRecPtr checkPointRedo, int flags)
 {
-	CheckPointRelationMap();
-	CheckPointReplicationSlots();
-	CheckPointSnapBuild();
-	CheckPointLogicalRewriteHeap();
-
-	/*
-	 * NEON: FIXME: we use logical recortds to persist information of about origins,
-	 * but writting in WAL during checkpoint at shutdown cause PANIC:
-	 * "concurrent write-ahead log activity while database system is shutting down"
-	 */
 	if (!(flags & CHECKPOINT_IS_SHUTDOWN))
-		CheckPointReplicationOrigin();
+		CheckPointReplicationState();
 
 	/* Write out all dirty data in SLRUs and the main buffer pool */
 	TRACE_POSTGRESQL_BUFFER_CHECKPOINT_START(flags);