fix race between logging parralel-safe message and acquiring participantsMask during simultaneous commit

kelvich · kelvich · commit fbb98ce03012 · 2019-01-15T16:45:26.000+03:00
diff --git a/src/pglogical_proto.c b/src/pglogical_proto.c
@@ -813,13 +813,15 @@ MtmReplicationStartupHook(struct PGLogicalStartupHookArgs* args)
 		 */
 		if (!hooks_data->is_recovery)
 		{
+			XLogRecPtr msg_xptr;
 			char *dest_id = psprintf("%d", MtmReplicationNodeId);
 
 			LWLockAcquire(MtmCommitBarrier, LW_EXCLUSIVE);
 			MtmStateProcessNeighborEvent(MtmReplicationNodeId, MTM_NEIGHBOR_WAL_SENDER_START_RECOVERED, false);
+			msg_xptr = LogLogicalMessage("P", dest_id, strlen(dest_id) + 1, false);
 			LWLockRelease(MtmCommitBarrier);
 
-			XLogFlush(LogLogicalMessage("P", dest_id, strlen(dest_id) + 1, false));
+			XLogFlush(msg_xptr);
 		}
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -813,13 +813,15 @@ MtmReplicationStartupHook(struct PGLogicalStartupHookArgs* args)`
`813`	`813`	`*/`
`814`	`814`	`if (!hooks_data->is_recovery)`
`815`	`815`	`{`
	`816`	`+ XLogRecPtr msg_xptr;`
`816`	`817`	`char *dest_id = psprintf("%d", MtmReplicationNodeId);`
`817`	`818`
`818`	`819`	`LWLockAcquire(MtmCommitBarrier, LW_EXCLUSIVE);`
`819`	`820`	`MtmStateProcessNeighborEvent(MtmReplicationNodeId, MTM_NEIGHBOR_WAL_SENDER_START_RECOVERED, false);`
	`821`	`+ msg_xptr = LogLogicalMessage("P", dest_id, strlen(dest_id) + 1, false);`
`820`	`822`	`LWLockRelease(MtmCommitBarrier);`
`821`	`823`
`822`		`- XLogFlush(LogLogicalMessage("P", dest_id, strlen(dest_id) + 1, false));`
	`824`	`+ XLogFlush(msg_xptr);`
`823`	`825`	`}`
`824`	`826`	`}`
`825`	`827`