MDEV-34784 unhandled FK dependency with DML vs DDL

mysql-test/suite/galera/r/MDEV-34784.result

@@ -0,0 +1,31 @@
+connection node_2;
+connection node_1;
+CREATE TABLE parent (
+id INT PRIMARY KEY,
+KEY (id)
+) ENGINE=InnoDB;
+CREATE TABLE child (
+id INT PRIMARY KEY,
+parent_id INT DEFAULT NULL,
+FOREIGN KEY (parent_id) 
+REFERENCES parent(id)
+) ENGINE=InnoDB;
+connection node_2;
+SET SESSION wsrep_sync_wait = 0;
+SET GLOBAL wsrep_slave_threads=2;
+SET GLOBAL DEBUG_DBUG = "d,sync.wsrep_apply_toi";
+connection node_1;
+ALTER TABLE parent ADD COLUMN (j INT);
+connection node_2;
+SET DEBUG_SYNC = "now WAIT_FOR sync.wsrep_apply_toi_reached";
+connection node_1;
+INSERT INTO child(id) values (1);
+connection node_2;
+SET DEBUG_SYNC = "now SIGNAL signal.wsrep_apply_toi";
+SET SESSION wsrep_sync_wait = DEFAULT;
+SET DEBUG_SYNC = "RESET";
+SET GLOBAL DEBUG_DBUG = '';
+SET GLOBAL wsrep_slave_threads = DEFAULT;
+connection node_1;
+DROP TABLE child;
+DROP TABLE parent;

mysql-test/suite/galera/t/MDEV-34784.test

@@ -0,0 +1,71 @@
+#
+# Testing that foreign key constraint dependencies are correctly
+# recorded in write set preventing harmfull parallel applying.
+#
+# In this scenario foreign reference column in child table is left
+# NULL in a DML, and therefore the FK parent table is not appended
+# in the key set. DDL execution on parent table will require table
+# lock on FK child table
+#
+
+--source include/galera_cluster.inc
+--source include/have_debug.inc
+--source include/have_debug_sync.inc
+--source include/galera_have_debug_sync.inc
+
+CREATE TABLE parent (
+    id INT PRIMARY KEY,
+    KEY (id)
+) ENGINE=InnoDB;
+
+CREATE TABLE child (
+    id INT PRIMARY KEY,
+    parent_id INT DEFAULT NULL,
+    FOREIGN KEY (parent_id) 
+        REFERENCES parent(id)
+) ENGINE=InnoDB;
+
+
+# Set up sync point for TOI applying in node 2
+--connection node_2
+SET SESSION wsrep_sync_wait = 0;
+SET GLOBAL wsrep_slave_threads=2;
+
+SET GLOBAL DEBUG_DBUG = "d,sync.wsrep_apply_toi";
+
+# replicate ALTER
+--connection node_1
+ALTER TABLE parent ADD COLUMN (j INT);
+
+# wait for ALTER to reach applying state
+--connection node_2
+SET DEBUG_SYNC = "now WAIT_FOR sync.wsrep_apply_toi_reached";
+
+#
+# Expect the INSERT to depend on the ALTER,
+# therefore it should wait for the ALTER to
+# finish before it can be applied.
+# If bug is present, the wait condition will
+# timeout
+#
+--let $expected_apply_waits = `SELECT VARIABLE_VALUE+1 FROM information_schema.global_status WHERE VARIABLE_NAME = 'wsrep_apply_waits'`
+
+--connection node_1
+# note, the FK column will have NULL value
+INSERT INTO child(id) values (1);
+
+# check that the INSERT depends on ALTER and waits for ALTER to complete first
+--connection node_2
+--let $wait_condition = SELECT VARIABLE_VALUE = $expected_apply_waits FROM information_schema.global_status WHERE VARIABLE_NAME = 'wsrep_apply_waits'
+--source include/wait_condition.inc
+SET DEBUG_SYNC = "now SIGNAL signal.wsrep_apply_toi";
+SET SESSION wsrep_sync_wait = DEFAULT;
+
+SET DEBUG_SYNC = "RESET";
+SET GLOBAL DEBUG_DBUG = '';
+SET GLOBAL wsrep_slave_threads = DEFAULT;
+
+--connection node_1
+DROP TABLE child;
+DROP TABLE parent;
+

sql/wsrep_mysqld.cc

@@ -1844,14 +1844,30 @@ bool wsrep_append_fk_parent_table(THD *thd, TABLE_LIST *tables,
       FOREIGN_KEY_INFO *f_key_info;
       List<FOREIGN_KEY_INFO> f_key_list;
 
-      table->table->file->get_foreign_key_list(thd, &f_key_list);
-      List_iterator_fast<FOREIGN_KEY_INFO> it(f_key_list);
-      while ((f_key_info= it++))
+      /* find FK parents */
       {
-        WSREP_DEBUG("appended fkey %s", f_key_info->referenced_table->str);
-        keys->push_back(wsrep_prepare_key_for_toi(
+        table->table->file->get_foreign_key_list(thd, &f_key_list);
+        List_iterator_fast<FOREIGN_KEY_INFO> it(f_key_list);
+        while ((f_key_info= it++))
+        {
+          WSREP_DEBUG("appended parent FK key %s", f_key_info->referenced_table->str);
+          keys->push_back(wsrep_prepare_key_for_toi(
             f_key_info->referenced_db->str, f_key_info->referenced_table->str,
             wsrep::key::shared));
+        }
+      }
+
+      /* find FK children */
+      {
+        table->table->file->get_parent_foreign_key_list(thd, &f_key_list);
+        List_iterator_fast<FOREIGN_KEY_INFO> it(f_key_list);
+        while ((f_key_info= it++))
+        {
+          WSREP_DEBUG("appended child FK key %s", f_key_info->foreign_table->str);
+          keys->push_back(wsrep_prepare_key_for_toi(
+            f_key_info->foreign_db->str, f_key_info->foreign_table->str,
+            wsrep::key::shared));
+        }
       }
     }
   }

storage/innobase/lock/lock0lock.cc

@@ -567,7 +567,11 @@ static void wsrep_assert_valid_bf_bf_wait(const lock_t *lock, const trx_t *trx,
 		    << " index: "
 		    << lock->index->name()
 		    << " that has lock ";
-	lock_rec_print(stderr, lock, mtr);
+	if (!lock->is_table()) {
+		lock_rec_print(stderr, lock, mtr);
+	} else {
+		lock_table_print(stderr, lock);
+	}
 
 	ib::error() << "WSREP state: ";
 
@@ -1068,10 +1072,20 @@ void wsrep_report_error(const lock_t* victim_lock, const trx_t *bf_trx)
   // should not execute concurrently
   mtr_t mtr;
   WSREP_ERROR("BF request is not compatible with victim");
+
+  auto print_lock_details = [&](const lock_t* lock) {
+    if (!lock->is_table()) {
+      lock_rec_print(stderr, lock, mtr);
+    } else {
+      lock_table_print(stderr, lock);
+    }
+  };
+
   WSREP_ERROR("BF requesting lock: ");
-  lock_rec_print(stderr, bf_trx->lock.wait_lock, mtr);
+  print_lock_details(bf_trx->lock.wait_lock);
+
   WSREP_ERROR("victim holding lock: ");
-  lock_rec_print(stderr, victim_lock, mtr);
+  print_lock_details(victim_lock);
 }
 #endif /* WITH_DEBUG */