Bug#21942487 ASSERTION `STATIC_CAST<SQL_CMD_XA_COMMIT*>(THD->LEX->M_SQL_CMD)-> GET_XA_OPT()

Bug#22273964 	INNODB: FAILING ASSERTION: TOTAL_TRX >= TRX_SYS->N_PREPARED_TRX

**Problem description**

An assertion of Bug#21942487

static_cast<Sql_cmd_xa_commit*>(thd->lex->m_sql_cmd)->
                              get_xa_opt() == XA_ONE_PHASE

#8  0x0000000000e3a5e1 in ha_commit_low
#9  0x00000000015158e6 in TC_LOG_DUMMY::commit
#10 0x0000000001529bc3 in Sql_cmd_xa_commit::trans_xa_commit

was caused by incorrect assumption by XA binlogging of wl6860 in
that @@session.pseudo_slave_mode can be only set 1 through binlog.
If fact the var can be set so manually.

Another assert in Bug#22273964 takes place for the very same reason.

**Solution**

The most reliable way to identify that the executing thread
is a binlog applier must include both the checking of rli_fake
and @@session.pseudo_slave_mode.
The former merely checking of the session variable as atttemp to
identify the binlog applier is replaced by checking the conjuction
of the two properties.

Notice that load containting SET @@session.pseudo_slave_mode=1 and
BINLOG '' pseudo-queries is not necessary authentic to mysqlbinlog output.
Nevertheless it must be processable when it's manually engineered such way.
A test is included to prove that as well.

**Note**
Beware of Bug #19502202 SERVER SHUTDOWN HANG SEEN IN SOME INNODB & RPL TESTS
at testing with binlog.binlog_xa_prepared_disconnect that still fails sporadically.

Author: Andrei Elkin

mysql-test/extra/binlog_tests/binlog_xa_prepared.test

@@ -56,6 +56,8 @@ CREATE VIEW v_processlist  as SELECT * FROM performance_schema.threads where typ
 
 --inc $not_xa_trans_committed
 --eval call mtr.add_suppression("Found $prepared_at_server_restart prepared XA transactions")
+# Caused by bug#79416 fixes, see below.
+call mtr.add_suppression("Found 1 prepared XA transactions");
 
 --inc $not_xa_trans_committed
 CREATE TABLE t (a INT) ENGINE=innodb;
@@ -151,6 +153,31 @@ if (`SELECT @@global.log_bin = 1`)
 --echo All transactions must be completed, to empty-list the following:
 XA RECOVER;
 
+
+# bug#79416 INNODB: FAILING ASSERTION: TOTAL_TRX >= TRX_SYS->N_PREPARED_TRX
+# Fixes' prove in that there must be no innodb assert at the server shutdown
+--connect (conn_bug79146, 127.0.0.1,root,,test,$MASTER_MYPORT,)
+CREATE TABLE t(a INT);
+XA START 'xa1';
+INSERT INTO t SET a = 1;
+XA END 'xa1';
+SET @@SESSION.pseudo_slave_mode=1;
+XA PREPARE 'xa1';
+
+--connection default
 --source include/restart_mysqld.inc
 
+XA ROLLBACK 'xa1';
+
+# bug78695 ASSERTION `STATIC_CAST<SQL_CMD_XA_COMMIT*>(THD->LEX->M_SQL_CMD)-> GET_XA_OPT()
+# Fixes' prove in that there must be no assert at the xa commit
+XA START 'xa1';
+INSERT INTO t SET a = 1;
+XA END 'xa1';
+XA PREPARE 'xa1';
+SET @@SESSION.pseudo_slave_mode=1;
+XA COMMIT 'xa1';
+
+DROP TABLE t;
+
 --source include/gtid_utils_end.inc

mysql-test/r/xa_prepared_binlog_off.result

@@ -2,6 +2,7 @@ call mtr.add_suppression("You need to use --log-bin to make --log-slave-updates
 include/gtid_utils.inc
 CREATE VIEW v_processlist  as SELECT * FROM performance_schema.threads where type = 'FOREGROUND';
 call mtr.add_suppression("Found 10 prepared XA transactions");
+call mtr.add_suppression("Found 1 prepared XA transactions");
 CREATE TABLE t (a INT) ENGINE=innodb;
 SET @@sql_log_bin = OFF;
 CREATE TEMPORARY TABLE tmp1 (a int) ENGINE=innodb;
@@ -809,5 +810,19 @@ include/assert.inc [committed gno 130]
 All transactions must be completed, to empty-list the following:
 XA RECOVER;
 formatID	gtrid_length	bqual_length	data
+CREATE TABLE t(a INT);
+XA START 'xa1';
+INSERT INTO t SET a = 1;
+XA END 'xa1';
+SET @@SESSION.pseudo_slave_mode=1;
+XA PREPARE 'xa1';
 # restart
+XA ROLLBACK 'xa1';
+XA START 'xa1';
+INSERT INTO t SET a = 1;
+XA END 'xa1';
+XA PREPARE 'xa1';
+SET @@SESSION.pseudo_slave_mode=1;
+XA COMMIT 'xa1';
+DROP TABLE t;
 include/gtid_utils_end.inc

mysql-test/suite/binlog/r/binlog_xa_handling.result

@@ -7,6 +7,22 @@ AAAAAAAAAAAAAAAAAABI6BZOEzgNAAgAEgAEBAQEEgAAVgAEGggAAAAICAgCAAAAAAVAYI8=';
 XA END'';
 XA PREPARE'';
 XA COMMIT'';
+SET @sav.pseudo_slave_mode= @@session.pseudo_slave_mode;
+SELECT  @@session.pseudo_slave_mode;
+@@session.pseudo_slave_mode
+0
+SET @@session.pseudo_slave_mode=1;
+Warnings:
+Warning	1231	'pseudo_slave_mode' is already ON.
+XA START 'xa';
+INSERT INTO t1 VALUES(10);
+BINLOG '
+SOgWTg8BAAAAbgAAAHIAAAAAAAQANS42LjMtbTUtZGVidWctbG9nAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAABI6BZOEzgNAAgAEgAEBAQEEgAAVgAEGggAAAAICAgCAAAAAAVAYI8=';
+XA END 'xa';
+XA PREPARE 'xa';
+XA COMMIT 'xa';
+SET @@session.pseudo_slave_mode= @sav.pseudo_slave_mode;
 DROP TABLE t1;
 RESET MASTER;
 CREATE TABLE t1 (c1 INT);

mysql-test/suite/binlog/r/binlog_xa_prepared_disconnect.result

@@ -2,6 +2,7 @@ include/gtid_utils.inc
 RESET MASTER;
 CREATE VIEW v_processlist  as SELECT * FROM performance_schema.threads where type = 'FOREGROUND';
 call mtr.add_suppression("Found 10 prepared XA transactions");
+call mtr.add_suppression("Found 1 prepared XA transactions");
 CREATE TABLE t (a INT) ENGINE=innodb;
 SET @@sql_log_bin = OFF;
 CREATE TEMPORARY TABLE tmp1 (a int) ENGINE=innodb;
@@ -811,6 +812,9 @@ master-bin.000001	#	Query	#	#	use `test`; CREATE ALGORITHM=UNDEFINED DEFINER=`ro
 master-bin.000001	#	Query	#	#	BEGIN
 master-bin.000001	#	Query	#	#	use `mtr`; INSERT INTO test_suppressions (pattern) VALUES ( NAME_CONST('pattern',_latin1'Found 10 prepared XA transactions' COLLATE 'latin1_swedish_ci'))
 master-bin.000001	#	Query	#	#	COMMIT
+master-bin.000001	#	Query	#	#	BEGIN
+master-bin.000001	#	Query	#	#	use `mtr`; INSERT INTO test_suppressions (pattern) VALUES ( NAME_CONST('pattern',_latin1'Found 1 prepared XA transactions' COLLATE 'latin1_swedish_ci'))
+master-bin.000001	#	Query	#	#	COMMIT
 master-bin.000001	#	Query	#	#	use `test`; CREATE TABLE t (a INT) ENGINE=innodb
 master-bin.000001	#	Query	#	#	XA START X'7472785f30',X'',1
 master-bin.000001	#	Query	#	#	use `test`; INSERT INTO t SET a=0
@@ -919,5 +923,19 @@ include/assert.inc [committed gno 130]
 All transactions must be completed, to empty-list the following:
 XA RECOVER;
 formatID	gtrid_length	bqual_length	data
+CREATE TABLE t(a INT);
+XA START 'xa1';
+INSERT INTO t SET a = 1;
+XA END 'xa1';
+SET @@SESSION.pseudo_slave_mode=1;
+XA PREPARE 'xa1';
 # restart
+XA ROLLBACK 'xa1';
+XA START 'xa1';
+INSERT INTO t SET a = 1;
+XA END 'xa1';
+XA PREPARE 'xa1';
+SET @@SESSION.pseudo_slave_mode=1;
+XA COMMIT 'xa1';
+DROP TABLE t;
 include/gtid_utils_end.inc

mysql-test/suite/binlog/t/binlog_xa_handling.test

@@ -11,6 +11,7 @@
 --source include/have_log_bin.inc
 
 CREATE TABLE t1(f1 int);
+
 XA START'','';
 INSERT INTO t1 VALUES(10);
 BINLOG '
@@ -19,6 +20,29 @@ AAAAAAAAAAAAAAAAAABI6BZOEzgNAAgAEgAEBAQEEgAAVgAEGggAAAAICAgCAAAAAAVAYI8=';
 XA END'';
 XA PREPARE'';
 XA COMMIT'';
+
+#
+# Bug#21942487 ASSERTION
+# `STATIC_CAST<SQL_CMD_XA_COMMIT*>(THD->LEX->M_SQL_CMDQL_CMD)->
+# GET_XA_OPT()
+# The following block checks safety of processing of load masquaraded
+# as it's out of mysqlbing. The XA transaction must complete.
+#
+SET @sav.pseudo_slave_mode= @@session.pseudo_slave_mode;
+SELECT  @@session.pseudo_slave_mode;
+# A warning out of the following query is improper and caused by a combination
+# of the above BINLOG processing and side effect of BUG#15891524.
+SET @@session.pseudo_slave_mode=1;
+XA START 'xa';
+INSERT INTO t1 VALUES(10);
+BINLOG '
+SOgWTg8BAAAAbgAAAHIAAAAAAAQANS42LjMtbTUtZGVidWctbG9nAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAABI6BZOEzgNAAgAEgAEBAQEEgAAVgAEGggAAAAICAgCAAAAAAVAYI8=';
+XA END 'xa';
+XA PREPARE 'xa';
+XA COMMIT 'xa';
+SET @@session.pseudo_slave_mode= @sav.pseudo_slave_mode;
+
 DROP TABLE t1;
 
 #

sql/handler.cc

@@ -1779,8 +1779,8 @@ int ha_commit_low(THD *thd, bool all, bool run_after_commit)
       have to restore its local thread native transaction
       context, previously saved at XA START.
     */
-    if (thd->variables.pseudo_slave_mode &&
-        thd->lex->sql_command == SQLCOM_XA_COMMIT)
+    if (thd->lex->sql_command == SQLCOM_XA_COMMIT &&
+        thd->binlog_applier_has_detached_trx())
     {
       DBUG_ASSERT(static_cast<Sql_cmd_xa_commit*>(thd->lex->m_sql_cmd)->
                   get_xa_opt() == XA_ONE_PHASE);

sql/rpl_rli.cc

@@ -115,7 +115,8 @@ Relay_log_info::Relay_log_info(bool is_slave_recovery
    commit_order_mngr(NULL),
    sql_delay(0), sql_delay_end(0), m_flags(0), row_stmt_start_timestamp(0),
    long_find_row_note_printed(false), error_on_rli_init_info(false),
-   thd_tx_priority(0)
+   thd_tx_priority(0),
+   is_native_trx_detached(false)
 {
   DBUG_ENTER("Relay_log_info::Relay_log_info");
 

sql/rpl_rli.h

@@ -1277,6 +1277,16 @@ class Relay_log_info : public Rpl_info
   int thd_tx_priority;
 
 public:
+  /*
+    The boolean is set to true when the binlog applier (rli_fake) thread
+    detaches any "native" engine transactions it has dealt with
+    at time of XA START processing.
+    The boolean is reset to false at the end of XA PREPARE
+    and XA COMMIT ONE PHASE, at the same time with the native transactions
+    re-attachment.
+  */
+  bool is_native_trx_detached;
+
   void set_thd_tx_priority(int priority)
   {
     thd_tx_priority= priority;

sql/sql_class.cc

@@ -4791,3 +4791,18 @@ void THD::claim_memory_ownership()
 #endif /* HAVE_PSI_MEMORY_INTERFACE */
 }
 
+
+bool THD::binlog_applier_need_detach_trx()
+{
+  return is_binlog_applier() ? rli_fake->is_native_trx_detached= true : false;
+};
+
+
+bool THD::binlog_applier_has_detached_trx()
+{
+  bool rc= is_binlog_applier() && rli_fake->is_native_trx_detached;
+
+  if (rc)
+    rli_fake->is_native_trx_detached= false;
+  return rc;
+}

sql/sql_class.h

@@ -1500,6 +1500,28 @@ class THD :public MDL_context_owner,
   /* Slave applier execution context */
   Relay_log_info* rli_slave;
 
+  /**
+    The function checks whether the thread is processing queries from binlog,
+    as automatically generated by mysqlbinlog.
+
+    @return true  when the thread is a binlog applier
+  */
+  bool is_binlog_applier() { return rli_fake && variables.pseudo_slave_mode; }
+
+  /**
+    @return true  when the thread is binlog applier.
+    @note When the thread is a binlog applier it memorizes a fact of that it
+          has detached "native" engine transactions associated with it.
+  */
+  bool binlog_applier_need_detach_trx();
+
+  /**
+    @return true   when the binlog applier (rli_fake) thread has detached
+                   "native" engine transaction, see @c binlog_applier_detach_trx.
+    @note The binlog applier having detached transactions resets a memo
+          mark at once with this check.
+  */
+  bool binlog_applier_has_detached_trx();
   void reset_for_next_command();
   /*
     Constant for THD::where initialization in the beginning of every query.

sql/xa.cc

@@ -569,7 +569,7 @@ bool Sql_cmd_xa_start::execute(THD *thd)
 
   if (!st)
   {
-    if (thd->variables.pseudo_slave_mode)
+    if (thd->binlog_applier_need_detach_trx())
     {
       /*
         In case of slave thread applier or processing binlog by client,
@@ -683,7 +683,7 @@ bool Sql_cmd_xa_prepare::execute(THD *thd)
 
   if (!st)
   {
-    if (!thd->variables.pseudo_slave_mode ||
+    if (!thd->binlog_applier_has_detached_trx() ||
         !(st= applier_reset_xa_trans(thd)))
       my_ok(thd);
   }