diff options
Diffstat (limited to 'sql/lock.cc')
| -rw-r--r-- | sql/lock.cc | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/sql/lock.cc b/sql/lock.cc index edc76fbe660..40a7a29942b 100644 --- a/sql/lock.cc +++ b/sql/lock.cc @@ -351,9 +351,25 @@ void mysql_lock_remove(THD *thd, MYSQL_LOCK *locked,TABLE *table) } } +/* Downgrade all locks on a table to new WRITE level from WRITE_ONLY */ + +void mysql_lock_downgrade_write(THD *thd, TABLE *table, + thr_lock_type new_lock_type) +{ + MYSQL_LOCK *locked; + TABLE *write_lock_used; + if ((locked = get_lock_data(thd,&table,1,1,&write_lock_used))) + { + for (uint i=0; i < locked->lock_count; i++) + thr_downgrade_write_lock(locked->locks[i], new_lock_type); + my_free((gptr) locked,MYF(0)); + } +} + + /* abort all other threads waiting to get lock in table */ -void mysql_lock_abort(THD *thd, TABLE *table) +void mysql_lock_abort(THD *thd, TABLE *table, bool upgrade_lock) { MYSQL_LOCK *locked; TABLE *write_lock_used; @@ -362,7 +378,7 @@ void mysql_lock_abort(THD *thd, TABLE *table) if ((locked = get_lock_data(thd,&table,1,1,&write_lock_used))) { for (uint i=0; i < locked->lock_count; i++) - thr_abort_locks(locked->locks[i]->lock); + thr_abort_locks(locked->locks[i]->lock, upgrade_lock); my_free((gptr) locked,MYF(0)); } DBUG_VOID_RETURN; @@ -598,18 +614,15 @@ static MYSQL_LOCK *get_lock_data(THD *thd, TABLE **table_ptr, uint count, lock_count++; } /* - To be able to open and lock for reading system tables like 'mysql.proc', - when we already have some tables opened and locked, and avoid deadlocks - we have to disallow write-locking of these tables with any other tables. + Check if we can lock the table. For some tables we cannot do that + beacause of handler-specific locking issues. */ - if (table_ptr[i]->s->system_table && - table_ptr[i]->reginfo.lock_type >= TL_WRITE_ALLOW_WRITE && - count != 1) - { - my_error(ER_WRONG_LOCK_OF_SYSTEM_TABLE, MYF(0), table_ptr[i]->s->db.str, - table_ptr[i]->s->table_name.str); + if (!table_ptr[i]-> file-> + check_if_locking_is_allowed(thd->lex->sql_command, thd->lex->type, + table_ptr[i], count, + (thd == logger.get_general_log_thd()) || + (thd == logger.get_slow_log_thd()))) DBUG_RETURN(0); - } } if (!(sql_lock= (MYSQL_LOCK*) |