diff options
| -rw-r--r-- | sql/events.cc | 27 | ||||
| -rw-r--r-- | sql/events.h | 8 | ||||
| -rw-r--r-- | sql/sys_vars.cc | 24 |
3 files changed, 34 insertions, 25 deletions
diff --git a/sql/events.cc b/sql/events.cc index d8bf549321e..a2375b1274b 100644 --- a/sql/events.cc +++ b/sql/events.cc @@ -1,4 +1,4 @@ -/* Copyright (C) 2004-2006 MySQL AB, 2008-2009 Sun Microsystems, Inc +/* Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -11,7 +11,7 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include "mysql_priv.h" #include "events.h" @@ -367,15 +367,14 @@ Events::create_event(THD *thd, Event_parse_data *parse_data, { sql_print_error("Event Error: An error occurred while creating query string, " "before writing it into binary log."); - /* Restore the state of binlog format */ - DBUG_ASSERT(!thd->is_current_stmt_binlog_format_row()); - if (save_binlog_row_based) - thd->set_current_stmt_binlog_format_row(); - DBUG_RETURN(TRUE); + ret= TRUE; + } + else + { + /* If the definer is not set or set to CURRENT_USER, the value of CURRENT_USER + will be written into the binary log as the definer for the SQL thread. */ + ret= write_bin_log(thd, TRUE, log_query.c_ptr(), log_query.length()); } - /* If the definer is not set or set to CURRENT_USER, the value of CURRENT_USER - will be written into the binary log as the definer for the SQL thread. */ - ret= write_bin_log(thd, TRUE, log_query.c_ptr(), log_query.length()); } } mysql_mutex_unlock(&LOCK_event_metadata); @@ -1017,7 +1016,11 @@ Events::dump_internal_status() puts("LLA = Last Locked At LUA = Last Unlocked At"); puts("WOC = Waiting On Condition DL = Data Locked"); - mysql_mutex_lock(&LOCK_event_metadata); + /* + opt_event_scheduler should only be accessed while + holding LOCK_global_system_variables. + */ + mysql_mutex_lock(&LOCK_global_system_variables); if (opt_event_scheduler == EVENTS_DISABLED) puts("The Event Scheduler is disabled"); else @@ -1026,7 +1029,7 @@ Events::dump_internal_status() event_queue->dump_internal_status(); } - mysql_mutex_unlock(&LOCK_event_metadata); + mysql_mutex_unlock(&LOCK_global_system_variables); DBUG_VOID_RETURN; } diff --git a/sql/events.h b/sql/events.h index 881ade37cbf..380b0d97f0a 100644 --- a/sql/events.h +++ b/sql/events.h @@ -1,6 +1,6 @@ #ifndef _EVENT_H_ #define _EVENT_H_ -/* Copyright (C) 2004-2006 MySQL AB, 2008-2009 Sun Microsystems, Inc +/* Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -13,7 +13,7 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ /** @defgroup Event_Scheduler Event Scheduler @@ -83,6 +83,7 @@ public: See sys_var.cc */ enum enum_opt_event_scheduler { EVENTS_OFF, EVENTS_ON, EVENTS_DISABLED }; + /* Protected using LOCK_global_system_variables only. */ static uint opt_event_scheduler; static mysql_mutex_t LOCK_event_metadata; static bool check_if_system_tables_error(); @@ -107,9 +108,6 @@ public: destroy_mutexes(); static bool - switch_event_scheduler_state(enum enum_opt_event_scheduler new_state); - - static bool create_event(THD *thd, Event_parse_data *parse_data, bool if_exists); static bool diff --git a/sql/sys_vars.cc b/sql/sys_vars.cc index 2e239a9161c..e14286210b4 100644 --- a/sql/sys_vars.cc +++ b/sql/sys_vars.cc @@ -1,4 +1,4 @@ -/* Copyright (C) 2002-2006 MySQL AB, 2009-2010 Sun Microsystems, Inc. +/* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -11,7 +11,7 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ /* How to add new variables: @@ -647,32 +647,40 @@ static bool event_scheduler_check(sys_var *self, THD *thd, set_var *var) } static bool event_scheduler_update(sys_var *self, THD *thd, enum_var_type type) { + uint opt_event_scheduler_value= Events::opt_event_scheduler; mysql_mutex_unlock(&LOCK_global_system_variables); /* Events::start() is heavyweight. In particular it creates a new THD, which takes LOCK_global_system_variables internally. Thus we have to release it here. We need to re-take it before returning, though. - And we need to take it *without* holding Events::LOCK_event_metadata. + + Note that since we release LOCK_global_system_variables before calling + start/stop, there is a possibility that the server variable + can become out of sync with the real event scheduler state. + + This can happen with two concurrent statments if the first gets + interrupted after start/stop but before retaking + LOCK_global_system_variables. However, this problem should be quite + rare and it's difficult to avoid it without opening up possibilities + for deadlocks. See bug#51160. */ - bool ret= Events::opt_event_scheduler == Events::EVENTS_ON + bool ret= opt_event_scheduler_value == Events::EVENTS_ON ? Events::start() : Events::stop(); - mysql_mutex_unlock(&Events::LOCK_event_metadata); mysql_mutex_lock(&LOCK_global_system_variables); - mysql_mutex_lock(&Events::LOCK_event_metadata); if (ret) my_error(ER_EVENT_SET_VAR_ERROR, MYF(0)); return ret; } -static PolyLock_mutex PLock_event_metadata(&Events::LOCK_event_metadata); + static Sys_var_enum Sys_event_scheduler( "event_scheduler", "Enable the event scheduler. Possible values are " "ON, OFF, and DISABLED (keep the event scheduler completely " "deactivated, it cannot be activated run-time)", GLOBAL_VAR(Events::opt_event_scheduler), CMD_LINE(OPT_ARG), event_scheduler_names, DEFAULT(Events::EVENTS_OFF), - &PLock_event_metadata, NOT_IN_BINLOG, + NO_MUTEX_GUARD, NOT_IN_BINLOG, ON_CHECK(event_scheduler_check), ON_UPDATE(event_scheduler_update)); #endif |