Merge 10.11 into 11.2

Author: dr-m

mysql-test/suite/galera/r/MDEV-33133.result

@@ -0,0 +1,34 @@
+connection node_2;
+connection node_1;
+connect node_1a,127.0.0.1,root,,test,$NODE_MYPORT_1;
+connection node_1;
+CREATE TABLE t1 (f1 INTEGER PRIMARY KEY) ENGINE=InnoDB;
+SET GLOBAL DEBUG_DBUG = 'd,sync.wsrep_rollback_mdl_release';
+connection node_2;
+SET SESSION wsrep_trx_fragment_size = 1;
+START TRANSACTION;
+INSERT INTO t1 VALUES (1);
+connection node_1a;
+SELECT COUNT(*) FROM t1;
+COUNT(*)
+0
+SET SESSION wsrep_retry_autocommit = 0;
+SET DEBUG_SYNC = 'ha_write_row_start SIGNAL may_toi WAIT_FOR bf_abort';
+INSERT INTO t1 VALUES (2);
+connection node_1;
+SET DEBUG_SYNC = 'now WAIT_FOR may_toi';
+SET DEBUG_SYNC = 'after_wsrep_thd_abort WAIT_FOR sync.wsrep_rollback_mdl_release_reached';
+TRUNCATE TABLE t1;
+connection node_1a;
+ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
+SET DEBUG_SYNC = 'now SIGNAL signal.wsrep_rollback_mdl_release';
+connection node_2;
+INSERT INTO t1 VALUES (3);
+ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
+connection node_1;
+SET GLOBAL DEBUG_DBUG = '';
+SET DEBUG_SYNC = 'RESET';
+DROP TABLE t1;
+disconnect node_1a;
+disconnect node_2;
+disconnect node_1;

mysql-test/suite/galera/t/MDEV-33133.test

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+#
+# MDEV-33133: MDL conflict handling code should skip transactions
+# BF-aborted before.
+#
+# It's possible that MDL conflict handling code is called more
+# than once for a transaction when:
+# - it holds more than one conflicting MDL lock
+# - reschedule_waiters() is executed,
+# which results in repeated attempts to BF-abort already aborted
+# transaction.
+# In such situations, it might be that BF-aborting logic sees
+# a partially rolled back transaction and erroneously decides
+# on future actions for such a transaction.
+#
+# The specific situation tested and fixed is when a SR transaction
+# applied in the node gets BF-aborted by a started TOI operation.
+# It's then caught with the server transaction already rolled back,
+# but with no MDL locks yet released. This caused wrong state
+# detection for such a transaction during repeated MDL conflict
+# handling code execution.
+#
+
+--source include/galera_cluster.inc
+--source include/have_debug_sync.inc
+--source include/have_debug.inc
+
+--connect node_1a,127.0.0.1,root,,test,$NODE_MYPORT_1
+
+--connection node_1
+CREATE TABLE t1 (f1 INTEGER PRIMARY KEY) ENGINE=InnoDB;
+SET GLOBAL DEBUG_DBUG = 'd,sync.wsrep_rollback_mdl_release';
+
+--connection node_2
+SET SESSION wsrep_trx_fragment_size = 1;
+START TRANSACTION;
+INSERT INTO t1 VALUES (1);
+
+--connection node_1a
+# Sync wait for SR transaction to replicate and apply fragment.
+SELECT COUNT(*) FROM t1;
+SET SESSION wsrep_retry_autocommit = 0;
+SET DEBUG_SYNC = 'ha_write_row_start SIGNAL may_toi WAIT_FOR bf_abort';
+--send
+  INSERT INTO t1 VALUES (2);
+
+--connection node_1
+SET DEBUG_SYNC = 'now WAIT_FOR may_toi';
+# BF-abort SR transaction and wait until it reaches the point
+# prior to release MDL locks.
+# Then abort local INSERT, which will go through rescedule_waiters()
+# and see SR transaction holding MDL locks but already rolled back.
+# In this case SR transaction should be skipped in MDL conflict
+# handling code.
+SET DEBUG_SYNC = 'after_wsrep_thd_abort WAIT_FOR sync.wsrep_rollback_mdl_release_reached';
+--send
+  TRUNCATE TABLE t1;
+
+--connection node_1a
+# Local INSERT gets aborted.
+--error ER_LOCK_DEADLOCK
+--reap
+# Let the aborted SR transaction continue and finally release MDL locks,
+# which in turn allows TRUNCATE to complete.
+SET DEBUG_SYNC = 'now SIGNAL signal.wsrep_rollback_mdl_release';
+
+--connection node_2
+# SR transaction has been BF-aborted.
+--error ER_LOCK_DEADLOCK
+INSERT INTO t1 VALUES (3);
+
+--connection node_1
+# TRUNCATE completes.
+--reap
+
+# Cleanup
+SET GLOBAL DEBUG_DBUG = '';
+SET DEBUG_SYNC = 'RESET';
+DROP TABLE t1;
+--disconnect node_1a
+--source include/galera_end.inc