--source include/have_innodb.inc
# The test is not format specific, MIXED is required to optimize testing time
--source include/have_binlog_format_mixed.inc
--source include/master-slave.inc

--echo #
--echo # MDEV-21953: deadlock between BACKUP STAGE BLOCK_COMMIT and parallel
--echo # replication
--echo #

--connection master
CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE = innodb;
# MDEV-515 takes X-lock on the table for the first insert.
# So concurrent insert won't happen on the table
INSERT INTO t1 VALUES(100);

--sync_slave_with_master
--source include/stop_slave.inc
SET @old_parallel_threads= @@GLOBAL.slave_parallel_threads;
SET @old_parallel_mode   = @@GLOBAL.slave_parallel_mode;
SET @@global.slave_parallel_threads= 2;
SET @@global.slave_parallel_mode   = 'optimistic';

--connection master
INSERT INTO  t1 VALUES (1);
INSERT INTO  t1 VALUES (2);
--save_master_pos

# The plot:
# Block the 1st of two workers and, at waiting-for-prior-commit by the 2nd,
# issue BACKUP commands.
# BLOCK_COMMIT may hang so it is --send.
# Release the 1st worker to observe a deadlock unless its fixed.

--connect (aux_slave,127.0.0.1,root,,test,$SLAVE_MYPORT,)
BEGIN;
# block the 1st worker and wait for the 2nd ready to commit
INSERT INTO t1 VALUES (1);

--connection slave
--source include/start_slave.inc

--connection aux_slave
--let $wait_condition= SELECT COUNT(*) > 0 FROM information_schema.processlist WHERE state = "Waiting for prior transaction to commit"
--source include/wait_condition.inc

# While the 1st worker is locked out run backup
--connect (backup_slave,127.0.0.1,root,,test,$SLAVE_MYPORT,)
BACKUP STAGE START;
--send BACKUP STAGE BLOCK_COMMIT

# release the 1st work
--connection aux_slave
--sleep 1
ROLLBACK;

--connection backup_slave
--reap
BACKUP STAGE END;

--connection slave
--sync_with_master

--let $diff_tables= master:t1,slave:t1
--source include/diff_tables.inc


# Clean up.
--connection slave
--source include/stop_slave.inc
SET @@global.slave_parallel_threads= @old_parallel_threads;
SET @@global.slave_parallel_mode   = @old_parallel_mode;
--source include/start_slave.inc

--connection server_1
DROP TABLE t1;

--source include/rpl_end.inc