config root man

--source include/have_debug.inc
--source include/have_innodb.inc
--source include/have_debug_sync.inc
--source include/count_sessions.inc

--echo #
--echo # Bug #21983865  UNEXPECTED DEADLOCK WITH INNODB_AUTOINC_LOCK_MODE=0
--echo #

create table t1(f1 int not null auto_increment primary key) engine=innodb;

--echo # Hold autoinc_lock on table t1 from connection con1
connect (con1, localhost, root);
set debug_sync='ib_after_row_insert SIGNAL others WAIT_FOR continue_others';
--send insert into t1 values(NULL)

connection default;
--echo # Create 40 connections and make it to wait for autoinc_lock on table t1.
--disable_query_log
set debug_sync='now WAIT_FOR others';
let $1=2;
while ($1 < 40) {
 connect (con$1,localhost,root);
 --send insert into t1 values(NULL)
 inc $1;
 connection default;
}

connect (con40,localhost,root);
--enable_query_log
--echo # Release the auto_inc lock on table t1 for connection con1
set debug_sync='now SIGNAL continue_others';

--echo # Now all 40 connections can finish the insert operation on t1.
let $1=1;
connection default;
disconnect con40;
while ($1 < 40) {
 connection con$1;
 --reap
 connection default;
 disconnect con$1;
 inc $1;
}

drop table t1;
--source include/wait_until_count_sessions.inc