erts: Add lock order check for route nodes

Lock order is reverse tree depth, from leafs toward root.

This solution may eventually fail if running too long
as route nodes do not increase their 'lc_order' in a join operation
when they move up in the tree.

But who runs a VM with lock-checker for such a long time?

1 files changed, 3 insertions, 0 deletions

diff --git a/erts/emulator/beam/erl_db_catree.h b/erts/emulator/beam/erl_db_catree.h
index 07a48d5bd3..0ad921d880 100644
--- a/erts/emulator/beam/erl_db_catree.h
+++ b/erts/emulator/beam/erl_db_catree.h
@@ -53,6 +53,9 @@ typedef struct {
 } DbTableCATreeBaseNode;
 
 typedef struct {
+#ifdef ERTS_ENABLE_LOCK_CHECK
+    Sint lc_order;
+#endif
     ErtsThrPrgrLaterOp free_item; /* Used when freeing using thread progress */
     erts_mtx_t lock; /* Used when joining route nodes */
     int is_valid; /* If this route node is still valid */