MDEV-17262: mysql crashed on galera while node rejoined cluster (#895)

This patch contains a fix for the MDEV-17262/17243 issues and
new mtr test.

These issues (MDEV-17262/17243) have two reasons:

1) After an intermediate commit, a transaction loses its status
of "transaction that registered in the MySQL for 2pc coordinator"
(in the InnoDB) due to the fact that since version 10.2 the
write_row() function (which located in the ha_innodb.cc) does
not call trx_register_for_2pc(m_prebuilt->trx) during the processing
of split transactions. It is necessary to restore this call inside
the write_row() when an intermediate commit was made (for a split
transaction).

Similarly, we need to set the flag of the started transaction
(m_prebuilt->sql_stat_start) after intermediate commit.

The table->file->extra(HA_EXTRA_FAKE_START_STMT) called from the
wsrep_load_data_split() function (which located in sql_load.cc)
will also do this, but it will be too late. As a result, the call
to the wsrep_append_keys() function from the InnoDB engine may be
lost or function may be called with invalid transaction identifier.

2) If a transaction with the LOAD DATA statement is divided into
logical mini-transactions (of the 10K rows) and binlog is rotated,
then in rare cases due to the wsrep handler re-registration at the
boundary of the split, the last portion of data may be lost. Since
splitting of the LOAD DATA into mini-transactions is technical,
I believe that we should not allow these mini-transactions to fall
into separate binlogs. Therefore, it is necessary to prohibit the
rotation of binlog in the middle of processing LOAD DATA statement.

https://jira.mariadb.org/browse/MDEV-17262 and
https://jira.mariadb.org/browse/MDEV-17243

1 files changed, 6 insertions, 0 deletions

diff --git a/include/mysql/service_wsrep.h b/include/mysql/service_wsrep.h
index ee28856ac73..7237cccfaeb 100644
--- a/include/mysql/service_wsrep.h
+++ b/include/mysql/service_wsrep.h
@@ -108,6 +108,8 @@ extern struct wsrep_service_st {
   long long                   (*wsrep_thd_trx_seqno_func)(THD *thd);
   struct wsrep_ws_handle *    (*wsrep_thd_ws_handle_func)(THD *thd);
   void                        (*wsrep_thd_auto_increment_variables_func)(THD *thd, unsigned long long *offset, unsigned long long *increment);
+  void                        (*wsrep_set_load_multi_commit_func)(THD *thd, bool split);
+  bool                        (*wsrep_is_load_multi_commit_func)(THD *thd);
   int                         (*wsrep_trx_is_aborting_func)(MYSQL_THD thd);
   int                         (*wsrep_trx_order_before_func)(MYSQL_THD, MYSQL_THD);
   void                        (*wsrep_unlock_rollback_func)();
@@ -152,6 +154,8 @@ extern struct wsrep_service_st {
 #define wsrep_thd_trx_seqno(T) wsrep_service->wsrep_thd_trx_seqno_func(T)
 #define wsrep_thd_ws_handle(T) wsrep_service->wsrep_thd_ws_handle_func(T)
 #define wsrep_thd_auto_increment_variables(T,O,I) wsrep_service->wsrep_thd_auto_increment_variables_func(T,O,I)
+#define wsrep_set_load_multi_commit(T,S) wsrep_service->wsrep_set_load_multi_commit_func(T,S)
+#define wsrep_is_load_multi_commit(T) wsrep_service->wsrep_is_load_multi_commit_func(T)
 #define wsrep_trx_is_aborting(T) wsrep_service->wsrep_trx_is_aborting_func(T)
 #define wsrep_trx_order_before(T1,T2) wsrep_service->wsrep_trx_order_before_func(T1,T2)
 #define wsrep_unlock_rollback() wsrep_service->wsrep_unlock_rollback_func()
@@ -206,6 +210,8 @@ my_bool wsrep_thd_is_wsrep(MYSQL_THD thd);
 struct wsrep *get_wsrep();
 struct wsrep_ws_handle *wsrep_thd_ws_handle(THD *thd);
 void wsrep_thd_auto_increment_variables(THD *thd, unsigned long long *offset, unsigned long long *increment);
+void wsrep_set_load_multi_commit(THD *thd, bool split);
+bool wsrep_is_load_multi_commit(THD *thd);
 void wsrep_aborting_thd_enqueue(THD *thd);
 void wsrep_lock_rollback();
 void wsrep_post_commit(THD* thd, bool all);