From: Date: April 4 2006 10:42pm Subject: bk commit into 5.1 tree (andrey:1.2234) BUG#17619 List-Archive: http://lists.mysql.com/commits/4461 X-Bug: 17619 Message-Id: <20060404204217.295EAF9E5@andrey.hristov.com> Below is the list of changes that have just been committed into a local 5.1 repository of andrey. When andrey does a push these changes will be propagated to the main repository and, within 24 hours after the push, to the public repository. For information on how to access the public repository see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html ChangeSet 1.2234 06/04/04 22:41:58 andrey@lmy004. +14 -0 Fix for bug#17619 (Scheduler race conditions) This is preliminary patch intended to have early review in the fixing process. The issue is big so this needs few revies during development. sql/event_scheduler.h 1.1 06/04/04 22:41:48 andrey@lmy004. +262 -0 sql/event_scheduler.cc 1.1 06/04/04 22:41:48 andrey@lmy004. +1695 -0 sql/event_scheduler.h 1.0 06/04/04 22:41:48 andrey@lmy004. +0 -0 BitKeeper file /work/mysql-5.1-bug17619-new/sql/event_scheduler.h sql/event_scheduler.cc 1.0 06/04/04 22:41:48 andrey@lmy004. +0 -0 BitKeeper file /work/mysql-5.1-bug17619-new/sql/event_scheduler.cc sql/sql_yacc.yy 1.485 06/04/04 22:41:47 andrey@lmy004. +10 -0 - parse SHOW EVENTS TEST sql/sql_parse.cc 1.535 06/04/04 22:41:47 andrey@lmy004. +18 -7 - run scheduler tests on SQLCOM_SHOW_EVENTS_TEST - let kill_one_thread() return whether there was an error or not and be silent if asked to be, makes it reusable in code that will send send_ok() on its own. sql/sql_lex.h 1.225 06/04/04 22:41:47 andrey@lmy004. +1 -1 add new command SQLCOM_SHOW_EVENTS_TEST, temporarily, for inside testing of the scheduler sql/set_var.cc 1.181 06/04/04 22:41:47 andrey@lmy004. +3 -1 - use the static member manager_working of Event_scheduler class, capsulation is better sql/mysql_priv.h 1.388 06/04/04 22:41:46 andrey@lmy004. +1 -1 let kill_one_thread() return whether there was an error or not sql/lex.h 1.157 06/04/04 22:41:46 andrey@lmy004. +1 -0 - add TEST as TEST_SYM. Needed for SHOW EVENTS TEST which is temporary code for testing the scheduler from inside the server with 1 command. sql/event_timed.cc 1.48 06/04/04 22:41:46 andrey@lmy004. +20 -0 Event_timed::kill_thread() stub, to implemented later, used by the current Event_scheduler_manager code sql/event_priv.h 1.21 06/04/04 22:41:46 andrey@lmy004. +6 -0 export db_find_event() and db_create_event() sql/event_executor.cc 1.42 06/04/04 22:41:46 andrey@lmy004. +17 -15 - init and destroy the LOCK_manager mutex of Event_schedule_manager sql/event.h 1.28 06/04/04 22:41:46 andrey@lmy004. +17 -4 move sortcmp_lex_string() so it is visible in the newly implemented Event_timed::same_name() sql/event.cc 1.38 06/04/04 22:41:46 andrey@lmy004. +2 -2 export db_create_event() and db_find_event() sql/Makefile.am 1.134 06/04/04 22:41:46 andrey@lmy004. +3 -3 add a new file event_scheduler.cc to the build # This is a BitKeeper patch. What follows are the unified diffs for the # set of deltas contained in the patch. The rest of the patch, the part # that BitKeeper cares about, is below these diffs. # User: andrey # Host: lmy004. # Root: /work/mysql-5.1-bug17619-new --- 1.133/sql/Makefile.am 2006-03-20 20:16:49 +01:00 +++ 1.134/sql/Makefile.am 2006-04-04 22:41:46 +02:00 @@ -65,8 +65,8 @@ noinst_HEADERS = item.h item_func.h item sp_head.h sp_pcontext.h sp_rcontext.h sp.h sp_cache.h \ parse_file.h sql_view.h sql_trigger.h \ sql_array.h sql_cursor.h event.h event_priv.h \ - sql_plugin.h authors.h sql_partition.h \ - partition_info.h partition_element.h + event_scheduler.h sql_plugin.h authors.h sql_partition.h \ + partition_info.h partition_element.h event_scheduler.h mysqld_SOURCES = sql_lex.cc sql_handler.cc sql_partition.cc \ item.cc item_sum.cc item_buff.cc item_func.cc \ item_cmpfunc.cc item_strfunc.cc item_timefunc.cc \ @@ -100,7 +100,7 @@ mysqld_SOURCES = sql_lex.cc sql_handler. tztime.cc my_time.c my_user.c my_decimal.cc\ sp_head.cc sp_pcontext.cc sp_rcontext.cc sp.cc \ sp_cache.cc parse_file.cc sql_trigger.cc \ - event_executor.cc event.cc event_timed.cc \ + event_executor.cc event.cc event_timed.cc event_scheduler.cc\ sql_plugin.cc sql_binlog.cc \ handlerton.cc sql_tablespace.cc partition_info.cc EXTRA_mysqld_SOURCES = ha_innodb.cc ha_berkeley.cc ha_archive.cc \ --- 1.156/sql/lex.h 2006-03-20 20:36:13 +01:00 +++ 1.157/sql/lex.h 2006-04-04 22:41:46 +02:00 @@ -521,6 +521,7 @@ static SYMBOL symbols[] = { { "TEMPORARY", SYM(TEMPORARY)}, { "TEMPTABLE", SYM(TEMPTABLE_SYM)}, { "TERMINATED", SYM(TERMINATED)}, + { "TEST", SYM(TEST_SYM)}, { "TEXT", SYM(TEXT_SYM)}, { "THAN", SYM(THAN_SYM)}, { "THEN", SYM(THEN_SYM)}, --- 1.387/sql/mysql_priv.h 2006-03-22 07:57:50 +01:00 +++ 1.388/sql/mysql_priv.h 2006-04-04 22:41:46 +02:00 @@ -83,7 +83,7 @@ char *sql_strmake_with_convert(const cha CHARSET_INFO *from_cs, uint32 max_res_length, CHARSET_INFO *to_cs, uint32 *result_length); -void kill_one_thread(THD *thd, ulong id, bool only_kill_query); +uint kill_one_thread(THD *thd, ulong id, bool only_kill_query, bool no_error); bool net_request_file(NET* net, const char* fname); char* query_table_status(THD *thd,const char *db,const char *table_name); --- 1.224/sql/sql_lex.h 2006-03-20 20:39:47 +01:00 +++ 1.225/sql/sql_lex.h 2006-04-04 22:41:47 +02:00 @@ -111,7 +111,7 @@ enum enum_sql_command { SQLCOM_SHOW_AUTHORS, SQLCOM_BINLOG_BASE64_EVENT, SQLCOM_SHOW_PLUGINS, SQLCOM_CREATE_EVENT, SQLCOM_ALTER_EVENT, SQLCOM_DROP_EVENT, - SQLCOM_SHOW_CREATE_EVENT, SQLCOM_SHOW_EVENTS, + SQLCOM_SHOW_CREATE_EVENT, SQLCOM_SHOW_EVENTS, SQLCOM_SHOW_EVENTS_TEST, /* This should be the last !!! */ --- 1.534/sql/sql_parse.cc 2006-03-21 13:10:09 +01:00 +++ 1.535/sql/sql_parse.cc 2006-04-04 22:41:47 +02:00 @@ -2030,7 +2030,7 @@ bool dispatch_command(enum enum_server_c { statistic_increment(thd->status_var.com_stat[SQLCOM_KILL], &LOCK_status); ulong id=(ulong) uint4korr(packet); - kill_one_thread(thd,id,false); + kill_one_thread(thd,id,false,false); break; } case COM_SET_OPTION: @@ -3860,6 +3860,13 @@ end_with_restore_list: res= evex_show_create_event(thd, lex->spname, lex->et->definer); break; } +#ifndef DBUG_OFF + case SQLCOM_SHOW_EVENTS_TEST: + { + res= Event_scheduler::run_tests(thd); + break; + } +#endif case SQLCOM_CREATE_FUNCTION: // UDF function { if (check_access(thd,INSERT_ACL,"mysql",0,1,0,0)) @@ -4099,7 +4106,7 @@ end_with_restore_list: MYF(0)); goto error; } - kill_one_thread(thd, (ulong)it->val_int(), lex->type & ONLY_KILL_QUERY); + kill_one_thread(thd, (ulong)it->val_int(), lex->type & ONLY_KILL_QUERY,false); break; } #ifndef NO_EMBEDDED_ACCESS_CHECKS @@ -6872,7 +6879,7 @@ bool reload_acl_and_cache(THD *thd, ulon This is written such that we have a short lock on LOCK_thread_count */ -void kill_one_thread(THD *thd, ulong id, bool only_kill_query) +uint kill_one_thread(THD *thd, ulong id, bool only_kill_query, bool no_error) { THD *tmp; uint error=ER_NO_SUCH_THREAD; @@ -6902,10 +6909,14 @@ void kill_one_thread(THD *thd, ulong id, pthread_mutex_unlock(&tmp->LOCK_delete); } - if (!error) - send_ok(thd); - else - my_error(error, MYF(0), id); + if (!no_error) + { + if (!error) + send_ok(thd); + else + my_error(error, MYF(0), id); + } + return error; } --- 1.484/sql/sql_yacc.yy 2006-03-21 13:10:10 +01:00 +++ 1.485/sql/sql_yacc.yy 2006-04-04 22:41:47 +02:00 @@ -630,6 +630,7 @@ bool my_yyoverflow(short **a, YYSTYPE ** %token TEMPORARY %token TEMPTABLE_SYM %token TERMINATED +%token TEST_SYM %token TEXT_STRING %token TEXT_SYM %token TIMESTAMP @@ -8149,6 +8150,15 @@ show_param: lex->select_lex.db= $3; if (prepare_schema_table(YYTHD, lex, 0, SCH_EVENTS)) YYABORT; + } + | EVENTS_SYM TEST_SYM + { +#ifdef DBUG_OFF + yyerror(ER(ER_SYNTAX_ERROR)); + YYABORT; +#else + Lex->sql_command= SQLCOM_SHOW_EVENTS_TEST; +#endif } | TABLE_SYM STATUS_SYM opt_db wild_and_where { --- 1.37/sql/event.cc 2006-02-28 20:32:30 +01:00 +++ 1.38/sql/event.cc 2006-04-04 22:41:46 +02:00 @@ -721,7 +721,7 @@ trunc_err: db_update_event. The name of the event is inside "et". */ -static int +int db_create_event(THD *thd, Event_timed *et, my_bool create_if_not, uint *rows_affected) { @@ -954,7 +954,7 @@ err: 2) tbl is not closed at exit */ -static int +int db_find_event(THD *thd, sp_name *name, LEX_STRING *definer, Event_timed **ett, TABLE *tbl, MEM_ROOT *root) { --- 1.27/sql/event.h 2006-03-16 13:14:32 +01:00 +++ 1.28/sql/event.h 2006-04-04 22:41:46 +02:00 @@ -19,6 +19,7 @@ #include "sp.h" #include "sp_head.h" +#include "event_scheduler.h" #define EVEX_OK SP_OK #define EVEX_KEY_NOT_FOUND SP_KEY_NOT_FOUND @@ -75,6 +76,8 @@ enum evex_table_field EVEX_FIELD_COUNT /* a cool trick to count the number of fields :) */ } ; +int sortcmp_lex_string(LEX_STRING s, LEX_STRING t, CHARSET_INFO *cs); + class Event_timed { Event_timed(const Event_timed &); /* Prevent use of these */ @@ -286,6 +289,20 @@ public: delete sphead; sphead= 0; } + + bool + same_name(Event_timed *etn) + { + return (!sortcmp_lex_string(etn->name, name, system_charset_info) && + !sortcmp_lex_string(etn->dbname, dbname, system_charset_info) && + !sortcmp_lex_string(etn->definer, definer, system_charset_info) + ); + } + + int + kill_thread(); + + protected: bool change_security_context(THD *thd, Security_context *s_ctx, @@ -314,8 +331,6 @@ evex_open_event_table(THD *thd, enum thr int evex_show_create_event(THD *thd, sp_name *spn, LEX_STRING definer); -int sortcmp_lex_string(LEX_STRING s, LEX_STRING t, CHARSET_INFO *cs); - int event_reconstruct_interval_expression(String *buf, interval_type interval, @@ -335,8 +350,6 @@ shutdown_events(); // auxiliary int event_timed_compare(Event_timed **a, Event_timed **b); - - /* CREATE TABLE event ( --- 1.41/sql/event_executor.cc 2006-03-01 04:21:57 +01:00 +++ 1.42/sql/event_executor.cc 2006-04-04 22:41:46 +02:00 @@ -17,6 +17,7 @@ #include "event_priv.h" #include "event.h" #include "sp.h" +#include "event_scheduler.h" #define WAIT_STATUS_READY 0 #define WAIT_STATUS_EMPTY_QUEUE 1 @@ -108,6 +109,7 @@ evex_init_mutexes() return; evex_mutexes_initted= TRUE; + pthread_mutex_init(&Event_scheduler::LOCK_manager, MY_MUTEX_INIT_FAST); pthread_mutex_init(&LOCK_event_arrays, MY_MUTEX_INIT_FAST); pthread_mutex_init(&LOCK_workers_count, MY_MUTEX_INIT_FAST); pthread_mutex_init(&LOCK_evex_running, MY_MUTEX_INIT_FAST); @@ -237,10 +239,17 @@ shutdown_events() evex_mutexes_initted= FALSE; VOID(pthread_mutex_lock(&LOCK_evex_running)); VOID(pthread_mutex_unlock(&LOCK_evex_running)); - + + if (Event_scheduler::destroy()) + { + DBUG_ASSERT(0); + sql_print_error("SCHEDULER: Trying to destroy while still running!"); + } pthread_mutex_destroy(&LOCK_event_arrays); pthread_mutex_destroy(&LOCK_workers_count); pthread_mutex_destroy(&LOCK_evex_running); + pthread_mutex_destroy(&Event_scheduler::LOCK_manager); + } DBUG_VOID_RETURN; } @@ -891,9 +900,9 @@ end: thread is started. SYNOPSIS - event_executor_worker() - thd - Thread context (unused) - car - the new value + sys_var_event_executor::update() + thd Thread context (unused) + var The new value Returns 0 OK (always) @@ -902,20 +911,13 @@ end: bool sys_var_event_executor::update(THD *thd, set_var *var) { + enum Event_scheduler::event_manager_op_code res; /* here start the thread if not running. */ DBUG_ENTER("sys_var_event_executor::update"); - VOID(pthread_mutex_lock(&LOCK_evex_running)); - *value= var->save_result.ulong_value; - - DBUG_PRINT("new_value", ("%d", *value)); - if ((my_bool) *value && !evex_is_running) - { - VOID(pthread_mutex_unlock(&LOCK_evex_running)); - init_events(); - } else - VOID(pthread_mutex_unlock(&LOCK_evex_running)); - DBUG_RETURN(0); + DBUG_PRINT("new_value", ("%d", (bool)var->save_result.ulong_value)); + DBUG_RETURN(Event_scheduler:: + event_scheduler_var_update(var->save_result.ulong_value)); } --- 1.20/sql/event_priv.h 2006-02-28 18:33:25 +01:00 +++ 1.21/sql/event_priv.h 2006-04-04 22:41:46 +02:00 @@ -46,7 +46,13 @@ event_timed_compare_q(void *vptr, byte* int db_drop_event(THD *thd, Event_timed *et, bool drop_if_exists, uint *rows_affected); +int +db_find_event(THD *thd, sp_name *name, LEX_STRING *definer, Event_timed **ett, + TABLE *tbl, MEM_ROOT *root); +int +db_create_event(THD *thd, Event_timed *et, my_bool create_if_not, + uint *rows_affected); #define EXEC_QUEUE_QUEUE_NAME executing_queue #define EXEC_QUEUE_DARR_NAME evex_executing_queue --- New file --- +++ sql/event_scheduler.cc 06/04/04 22:41:48 /* Copyright (C) 2004-2005 MySQL AB 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 the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. 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 */ #include "event_priv.h" #include "event.h" /* 1. Integrate the code with the already existing one. Call - add_event - drop_event - replace_event where appropriate 2. Fix kill_thread() in drop_event()/add_event(). */ #define CHECK_RUNNING(__ret_code) \ if (mode != MANAGER_RUNNING) \ { \ DBUG_PRINT("info", ("manager not running but %d. doing nothing", mode)); \ pthread_mutex_unlock(&LOCK_mutex); \ DBUG_RETURN(__ret_code); \ } #define SET_THD_INFO(__info) thd->proc_info= (char *)__info; Event_scheduler *Event_scheduler::ston= NULL; pthread_mutex_t Event_scheduler::LOCK_manager; my_bool Event_scheduler::manager_working= FALSE; extern bool evex_print_warnings(THD *thd, Event_timed *et); /* Inits an scheduler thread handler, both the main and a worker SYNOPSIS init_event_thread() thd - the THD of the thread. Has to be allocated by the caller. NOTES 1. The host of the thead is my_localhost 2. thd->net is initted with NULL - no communication. Returns 0 OK -1 Error */ static int init_event_thread(THD* thd) { DBUG_ENTER("init_event_thread"); thd->client_capabilities= 0; thd->security_ctx->master_access= 0; thd->security_ctx->db_access= 0; thd->security_ctx->host_or_ip= (char*)my_localhost; my_net_init(&thd->net, 0); thd->net.read_timeout = slave_net_timeout; thd->slave_thread= 0; thd->options|= OPTION_AUTO_IS_NULL; thd->client_capabilities= CLIENT_LOCAL_FILES; thd->real_id=pthread_self(); VOID(pthread_mutex_lock(&LOCK_thread_count)); thd->thread_id= thread_id++; threads.append(thd); thread_count++; thread_running++; VOID(pthread_mutex_unlock(&LOCK_thread_count)); if (init_thr_lock() || thd->store_globals()) { thd->cleanup(); delete thd; DBUG_RETURN(-1); } #if !defined(__WIN__) && !defined(OS2) && !defined(__NETWARE__) sigset_t set; VOID(sigemptyset(&set)); // Get mask in use VOID(pthread_sigmask(SIG_UNBLOCK,&set,&thd->block_signals)); #endif thd->proc_info= "Initialized"; thd->version= refresh_version; thd->set_time(); /* Guarantees that we will see the thread in SHOW PROCESSLIST though its vio is NULL. */ thd->system_thread= 1; DBUG_RETURN(0); } /* Inits the main manager thread and then calls Event_scheduler::run() of arg. SYNOPSIS event_scheduler_run_proxy() arg void* ptr to Event_scheduler NOTES 1. The host of the thead is my_localhost 2. thd->net is initted with NULL - no communication. 3. The reason to have a proxy function is that it's not possible to use a method as function to be executed in a spawned thread: - our pthread_hander_t macro uses extern "C" - separating thread setup from the real execution loop is also to be considered good. Returns 0 OK -1 Error */ pthread_handler_t event_scheduler_run_proxy(void *arg) { THD *thd= NULL; // needs to be first for thread_stack Event_scheduler *esm= (Event_scheduler *) arg; DBUG_ENTER("event_scheduler_run_proxy"); my_thread_init(); /* note that contructor of THD uses DBUG_ ! */ if (!(thd = new THD)) { sql_print_error("SCHEDULER: Cannot create THD for the main thread."); goto finish; } thd->thread_stack = (char*)&thd; // remember where our stack is pthread_detach_this_thread(); if (init_event_thread(thd)) { sql_print_error("SCHEDULER: Cannot init main event thread."); goto finish; } thd->security_ctx->user= my_strdup("event_scheduler", MYF(0)); sql_print_information("SCHEDULER: Main thread started"); esm->run(thd); /* NOTE: Don't touch `esm` after this point because we have notified the thread which shuts us down that we have finished cleaning. In this very moment a new manager thread could be started and a crash is not welcome. */ THD_CHECK_SENTRY(thd); finish: /* If we cannot create THD then don't decrease because we haven't touched thread_count and thread_running in init_event_thread() which was never called. In init_event_thread() thread_count and thread_running are always increased even in the case the method returns an error. */ if (thd) { pthread_mutex_lock(&LOCK_thread_count); thread_count--; thread_running--; pthread_mutex_unlock(&LOCK_thread_count); thd->proc_info = "Clearing"; DBUG_ASSERT(thd->net.buff != 0); net_end(&thd->net); THD_CHECK_SENTRY(thd); delete thd; } my_thread_end(); pthread_exit(0); DBUG_RETURN(0); // Can't return anything here } /* Function that executes an event in a child thread. Setups the environment for the event execution and cleans after that. SYNOPSIS event_worker_thread() arg The Event_timed object to be processed */ pthread_handler_t event_worker_thread(void *event_void) { THD *thd; /* needs to be first for thread_stack */ Event_timed *event = (Event_timed *) event_void; MEM_ROOT worker_mem_root; int ret; DBUG_ENTER("event_worker_thread"); my_thread_init(); if (!(thd = new THD)) /* note that contructor of THD uses DBUG_ ! */ { sql_print_error("SCHEDULER: Cannot create a THD structure in an worker."); goto finish; } thd->thread_stack = (char*)&thd; // remember where our stack is pthread_detach_this_thread(); if (init_event_thread(thd)) { sql_print_error("SCHEDULER: Cannot init worker thread."); goto finish; } /* This is specific to the worker thread which we don't do in the manager thread. Everything else in the init part is the same. */ thd->init_for_queries(); init_alloc_root(&worker_mem_root, MEM_ROOT_BLOCK_SIZE, MEM_ROOT_PREALLOC); thd->mem_root= &worker_mem_root; thd->enable_slow_log= TRUE; if (Event_scheduler::register_worker_thread(thd->thread_id)) sql_print_information("SCHEDULER: Error during register_worker_thread()"); else { sql_print_information("SCHEDULER: Executing event %s.%s of %s [EXPR:%d]", event->dbname.str, event->name.str, event->definer.str, (int) event->expression); ret= event->execute(thd, &worker_mem_root); evex_print_warnings(thd, event); sql_print_information("SCHEDULER: Executed event %s.%s of %s [EXPR:%d]. " "RetCode=%d", event->dbname.str, event->name.str, event->definer.str, (int) event->expression, ret); if (ret == EVEX_COMPILE_ERROR) sql_print_information("SCHEDULER: COMPILE ERROR for event %s.%s of %s", event->dbname.str, event->name.str, event->definer.str); else if (ret == EVEX_MICROSECOND_UNSUP) sql_print_information("SCHEDULER: MICROSECOND is not supported"); event->spawn_thread_finish(thd); } pthread_mutex_lock(&LOCK_thread_count); thread_count--; thread_running--; pthread_mutex_unlock(&LOCK_thread_count); free_root(&worker_mem_root, MYF(0)); finish: if (Event_scheduler::deregister_worker_thread(thd->thread_id)) sql_print_information("SCHEDULER: Error during deregister_worker_thread()"); if (thd) { thd->proc_info = "Clearing"; DBUG_ASSERT(thd->net.buff != 0); /* QQ: Is this needed THD::~THD does it too */ net_end(&thd->net); THD_CHECK_SENTRY(thd); VOID(pthread_mutex_lock(&LOCK_thread_count)); delete thd; VOID(pthread_mutex_unlock(&LOCK_thread_count)); } my_thread_end(); pthread_exit(0); DBUG_RETURN(0); // Can't return anything here } /* Returns singleton instance of the class Synopsis Event_scheduler::get_instance() Returns NULL Error address Success */ Event_scheduler* Event_scheduler::get_instance() { Event_scheduler *tmp= NULL; DBUG_ENTER("Event_scheduler::get_instance"); if (sizeof(my_time_t) != sizeof(time_t)) { sql_print_error("SCHEDULER: sizeof(my_time_t) != sizeof(time_t) ." "The scheduler will not work correctly. Stopping."); DBUG_ASSERT(0); DBUG_RETURN(NULL); } pthread_mutex_lock(&LOCK_manager); if (ston) goto skip_init; /* Check it rarely (when creating instance) but do check it */ check_system_tables(); if (!(tmp= new Event_scheduler)) goto err; if (init_queue_ex(&tmp->queue, 30 /*num_el*/, 0 /*offset*/, 0 /*smallest_on_top*/, event_timed_compare_q, NULL, 30 /*auto_extent*/)) { sql_print_error("SCHEDULER: Insufficient memory to initialize " "executing queue."); goto err; } if (pthread_mutex_init(&tmp->LOCK_mutex, MY_MUTEX_INIT_FAST)) { sql_print_error("SCHEDULER: Unable to initalize LOCK_mutex"); goto err; } if (pthread_cond_init(&tmp->COND_new_work, NULL)) { sql_print_error("SCHEDULER: Unable to initialize COND_new_work"); goto err; } if (pthread_cond_init(&tmp->COND_started, NULL)) { sql_print_error("SCHEDULER: Unable to initialize COND_started"); goto err; } if (pthread_cond_init(&tmp->COND_shutdown, NULL)) { sql_print_error("SCHEDULER: Unable to initialize COND_shutdown"); goto err; } if (pthread_mutex_init(&tmp->LOCK_last_worker_exit, MY_MUTEX_INIT_FAST)) { sql_print_error("SCHEDULER: Unable to initalize LOCK_last_worker_exit"); goto err; } if (pthread_cond_init(&tmp->COND_last_worker_exit, NULL)) { sql_print_error("SCHEDULER: Unable to initialize COND_last_worker_exit"); goto err; } #ifndef DBUG_OFF if (pthread_mutex_init(&tmp->LOCK_executed, MY_MUTEX_INIT_FAST)) { sql_print_error("SCHEDULER: Unable to initalize LOCK_executed"); goto err; } if (pthread_cond_init(&tmp->COND_executed, NULL)) { sql_print_error("SCHEDULER: Unable to initialize COND_executed"); goto err; } #endif /* init memory root */ init_alloc_root(&tmp->manager_root, MEM_ROOT_BLOCK_SIZE, MEM_ROOT_PREALLOC); my_init_dynamic_array(&tmp->workers, sizeof(ulong), 50, 100); tmp->mode= MANAGER_INIT; ston= tmp; skip_init: pthread_mutex_unlock(&LOCK_manager); DBUG_RETURN(ston); err: pthread_mutex_unlock(&LOCK_manager); delete tmp; DBUG_RETURN(NULL); } /* Adds an event to the scheduler queue Synopsis Event_scheduler::add_event() et The event to add Returns FALSE OK TRUE Failure */ bool Event_scheduler::add_event(THD *thd, Event_timed *et, bool check_existance) { Event_timed *et_new; DBUG_ENTER("Event_scheduler::add_event"); pthread_mutex_lock(&LOCK_mutex); CHECK_RUNNING(false); if (check_existance) if (find_event(et, false)) { pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(true); } /* We need to load the event on manager_root */ if ((et_new= load_and_compile_event(thd, et))) { queue_insert_safe(&queue, (byte *) et_new); pthread_cond_signal(&COND_new_work); } pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(!et_new); } /* Drops an event from the scheduler queue Synopsis Event_scheduler::drop_event() etn The event to drop mode Wait the event or kill&drop Returns FALSE OK TRUE Failure */ bool Event_scheduler::drop_event(THD *thd, Event_timed *etn, enum event_drop_mode drop_mode) { Event_timed *et; DBUG_ENTER("Event_scheduler::drop_event"); pthread_mutex_lock(&LOCK_mutex); CHECK_RUNNING(false); if ((et= find_event(etn, true))) { /* ToDo : Stop the event ! */ et->kill_thread(); /* We don't signal COND_new_work here because: 1. Even if the dropped event is on top of the queue this will not move another one to be executed before the time the one on the top (but could be at the same second as the dropped one) 2. If this was the last event on the queue, then pthread_cond_timedwait in ::run() will finish and then see that the queue is empty and call pthread_cond_wait(). Hence, no need to interrupt the blocked ::run() thread. */ } else DBUG_PRINT("info", ("no such event found")); pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(false); } /* Replaces an event in the scheduler queue Synopsis Event_scheduler::replace_event() et The event to replace(add) into the queue mode Wait the event or kill&drop Returns FALSE OK TRUE Failure */ bool Event_scheduler::replace_event(THD *thd, Event_timed *et, enum event_drop_mode replace_mode) { Event_timed *et_old, *et_new= NULL; DBUG_ENTER("Event_scheduler::replace_event"); pthread_mutex_lock(&LOCK_mutex); CHECK_RUNNING(false); /* ToDo : Stop the event ! */ if ((et_old= find_event(et, true))) et_old->kill_thread(); else DBUG_PRINT("info", ("%s.%s not found cached, probably was DISABLED", et->dbname.str, et->name.str)); /* We need to load the event on manager_root */ if ((et_new= load_and_compile_event(thd, et))) { queue_insert_safe(&queue, (byte *) et_new); pthread_cond_signal(&COND_new_work); } pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(!et_new); } /* Searches for an event in the scheduler queue Synopsis Event_scheduler::find_event() etn The event to find remove_from_q If found whether to remove from the Q Returns NULL Not found otherwise Address Notes The caller should do the locking also the caller is responsible for actual signalling in case an event is removed from the queue (signalling COND_new_work for instance). */ Event_timed * Event_scheduler::find_event(Event_timed *etn, bool remove_from_q) { uint i; DBUG_ENTER("Event_scheduler::find_event"); for (i= 0; i < queue.elements; ++i) { Event_timed *et= (Event_timed *) queue_element(&queue, i); DBUG_PRINT("info", ("[%s.%s]==[%s.%s]?", etn->dbname.str, etn->name.str, et->dbname.str, et->name.str)); if (etn->same_name(et)) { if (remove_from_q) queue_remove(&queue, i); DBUG_RETURN(et); } } DBUG_RETURN(NULL); } extern pthread_attr_t connection_attrib; /* Starts the event scheduler Synopsis Event_scheduler::start() Returns EVENT_OP_OK OK EVENT_OP_CANTFORK Cannot create a new thread EVENT_OP_CANTSTART ::run() had problem booting EVENT_OP_ALREADY_RUNNING Manager already running */ enum Event_scheduler::event_manager_op_code Event_scheduler::start() { enum event_manager_op_code ret; pthread_t th; DBUG_ENTER("Event_scheduler::start"); pthread_mutex_lock(&LOCK_mutex); /* If already working or starting don't make another attempt */ if (mode > MANAGER_INIT) { DBUG_PRINT("info", ("manager is already running or starting")); ret= EVENT_OP_ALREADY_RUNNING; goto finish; } /* Now if another thread calls start it will bail-out because the branch above will be executed. Thus no two or more child threads will be forked. If the child thread cannot start for some reason then `mode` is set to MANAGER_CANTSTART and COND_started is also signaled. In this case we set `mode` back to MANAGER_INIT so another attempt to start the manager can be made. */ mode= MANAGER_STARTING; manager_working= TRUE; /* Fork */ if (pthread_create(&th, &connection_attrib, event_scheduler_run_proxy, (void*)this)) { DBUG_PRINT("error", ("cannot create a new thread")); mode= MANAGER_INIT; ret= EVENT_OP_CANTFORK; goto finish; } /* Wait till the child thread has booted (w/ or wo success) */ while (mode != MANAGER_RUNNING && mode != MANAGER_CANTSTART) pthread_cond_wait(&COND_started, &LOCK_mutex); /* If we cannot start for some reason then don't prohibit further attempts. Set back to MANAGER_INIT. */ if (mode == MANAGER_CANTSTART) { mode= MANAGER_INIT; manager_working= FALSE; ret= EVENT_OP_CANTSTART; goto finish; } ret= EVENT_OP_OK; finish: pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(ret); } /* The internal loop of the event scheduler Synopsis Event_scheduler::run() Returns FALSE OK TRUE Failure */ bool Event_scheduler::run(THD *thd) { int ret; struct timespec abstime; DBUG_ENTER("Event_scheduler::run"); /* Load events from disk. `mode` is currently MANAGER_STARTING. Hence, there is no race between loading and add_event() because the latter won't touch the queue until the mode is not MANAGER_RUNNING, which is set a bit later in this function. */ ret= load_events_from_db(thd); pthread_mutex_lock(&LOCK_mutex); if (!ret) { thread_id= thd->thread_id; mode= MANAGER_RUNNING; } else mode= MANAGER_CANTSTART; DBUG_PRINT("info", ("Sending back COND_started")); pthread_cond_signal(&COND_started); pthread_mutex_unlock(&LOCK_mutex); if (ret) DBUG_RETURN(true); abstime.tv_nsec= 0; while (!thd->killed) { TIME time_now_utc; Event_timed *et; my_bool tmp; time_t now_utc; pthread_mutex_lock(&LOCK_mutex); if (mode != MANAGER_RUNNING) { pthread_mutex_unlock(&LOCK_mutex); break; } while (!queue.elements) { bool should_break; thd->enter_cond(&COND_new_work, &LOCK_mutex, "Empty queue, sleeping"); pthread_cond_wait(&COND_new_work, &LOCK_mutex); DBUG_PRINT("info", ("Woke up. mode is %d", mode)); should_break= (mode != MANAGER_RUNNING); thd->exit_cond(""); if (should_break) goto end_loop; } SET_THD_INFO("Computing"); et= (Event_timed *)queue_top(&queue); DBUG_PRINT("evex main thread",("computing time to sleep till next exec")); /* This timestamp is in UTC */ abstime.tv_sec= sec_since_epoch_TIME(&et->execute_at); thd->end_time(); if (abstime.tv_sec > thd->query_start()) { /* Event trigger time is in the future */ DBUG_PRINT("info", ("Going to sleep. Should wakeup after approx %d secs", abstime.tv_sec - thd->query_start())); SET_THD_INFO("Sleep"); sql_print_information("SCHEDULER: Going to sleep for %d secs", abstime.tv_sec - thd->query_start()); /* Use THD::enter_cond()/exit_cond() or we won't be able to kill a sleeping thread. Though ::shutdown() can do it by sending COND_new_work an user can't by just issuing 'KILL x'; . In the latter case pthread_cond_timedwait() will wait till `abstime`. */ thd->enter_cond(&COND_new_work, &LOCK_mutex, "Sleeping until next time"); pthread_cond_timedwait(&COND_new_work, &LOCK_mutex, &abstime); DBUG_PRINT("info", ("Woke up. mode is %d", mode)); /* If we get signal we should recalculate the whether it's the right time because there could be : 1. Spurious wake-up 2. The top of the queue was changed (new one becase of add/drop/replace) */ /* This will do implicit pthread_mutex_unlock(&LOCK_mutex) */ thd->exit_cond(""); } else { SET_THD_INFO("Executing"); /* Execute the event. An error may occur if a thread cannot be forked. In this case stop the manager. We should enter ::execute_top() with locked LOCK_mutex. */ int ret= execute_top(thd); pthread_mutex_unlock(&LOCK_mutex); if (ret) break; } } end_loop: SET_THD_INFO("Cleaning"); pthread_mutex_lock(&LOCK_mutex); /* It's possible that a user has used (SQL)COM_KILL. Hence set the appropriate mode because it is only set by ::shutdown(). */ if (mode != MANAGER_SHUTDOWN) { DBUG_PRINT("info", ("We got KILL but the but not from ::shutdown()")); mode= MANAGER_SHUTDOWN; } pthread_mutex_unlock(&LOCK_mutex); sql_print_information("SCHEDULER: Stopping"); SET_THD_INFO("Cleaning queue"); clean_queue(thd); /* free mamager_root memory but don't destroy the root */ SET_THD_INFO("Cleaning memory root"); free_root(&manager_root, MYF(0)); /* We notify the waiting thread which shutdowns us that we have cleaned. There are few more instructions to be executed in this pthread but they don't affect manager structures thus it's safe to signal already at this point. */ pthread_mutex_lock(&LOCK_mutex); SET_THD_INFO("Sending shutdown signal"); DBUG_PRINT("info", ("Sending COND_shutdown")); if (mode == MANAGER_SHUTDOWN) pthread_cond_signal(&COND_shutdown); /* Don't set mode to MANAGER_STOPPED because ::start() checks (mode > MANAGER_INIT) to decide whether it can fork a new thread or return. MANAGER_STOPPED is used by the dtor of Event_scheduler, thus preventing a fork of a new thread while the manager object is being destroyed. */ mode= MANAGER_INIT; /* We set it here because ::run() can stop not only because of ::shutdown() call but also because of `KILL x` */ manager_working= FALSE; thread_id= 0; sql_print_information("SCHEDULER: Stopped."); pthread_mutex_unlock(&LOCK_mutex); /* We have modified the following with the SET_THD_INFO macro - set back */ thd->query= NULL; thd->query_length= 0; DBUG_RETURN(false); } /* Executes the top element of the queue. Auxiliary method for ::run(). Synopsis Event_scheduler::execute_top() Notes NO locking is done. EXPECTED is that the caller should have locked the queue (w/ LOCK_mutex). Returns FALSE OK TRUE Failure */ bool Event_scheduler::execute_top(THD *thd) { int fork_ret_code; DBUG_ENTER("Event_scheduler::execute_top"); Event_timed *et= (Event_timed *)queue_top(&queue); DBUG_PRINT("info", ("SCHEDULER: execute_at of %s is %lld", et->name.str, TIME_to_ulonglong_datetime(&et->execute_at))); sql_print_information("SCHEDULER: Executed %s", et->name.str, TIME_to_ulonglong_datetime(&et->execute_at)); et->mark_last_executed(thd); if (et->compute_next_execution_time()) { sql_print_error("SCHEDULER: Error while computing time of %s.%s . " "Disabling after execution.", et->dbname.str, et->name.str); et->status= MYSQL_EVENT_DISABLED; } DBUG_PRINT("evex main thread", ("[%10s] next exec at [%llu]", et->name.str, TIME_to_ulonglong_datetime(&et->execute_at))); et->update_fields(thd); /* We don't lock LOCK_mutex here because it's a pre-requisite for calling the current_method. */ workers_increment(thd->thread_id); switch ((fork_ret_code= et->spawn_now(event_worker_thread))) { case EVENT_EXEC_CANT_FORK: /* We don't lock LOCK_mutex here because it's a pre-requisite for calling the current_method. We pass 0 to workers_decrement() because there was no thread forked and only workers_count should be updated but not the `workers` dynamic array */ workers_decrement(0); sql_print_error("SCHEDULER: Problem while trying to create a thread"); DBUG_RETURN(true); case EVENT_EXEC_ALREADY_EXEC: /* We don't lock LOCK_mutex here because it's a pre-requisite for calling the current_method. We pass 0 to workers_decrement() because there was no thread forked and only workers_count should be updated but not the `workers` dynamic array */ workers_decrement(0); sql_print_information("SCHEDULER: %s.%s in execution. Skip this time.", et->dbname.str, et->name.str); break; default: DBUG_ASSERT(!fork_ret_code); /* We don't lock LOCK_mutex here because it's a pre-requisite for calling the current_method. We pass 0 to workers_decrement() because there was no thread forked and only workers_count should be updated but not the `workers` dynamic array */ if (unlikely(fork_ret_code)) workers_decrement(0); #ifndef DBUG_OFF else { pthread_mutex_lock(&LOCK_executed); pthread_cond_signal(&COND_executed); pthread_mutex_unlock(&LOCK_executed); } #endif break; } /* 1. For one-time event : year is > 0 and expression is 0 2. For recurring, expression is != -=> check execute_at_null in this case */ if ((et->execute_at.year && !et->expression) || et->execute_at_null) et->flags |= EVENT_EXEC_NO_MORE; if ((et->flags & EVENT_EXEC_NO_MORE) || et->status == MYSQL_EVENT_DISABLED) queue_remove(&queue, 0);// 0 is top, internally 1 else queue_replaced(&queue); DBUG_RETURN(false); } /* Cleans the scheduler's queue. Auxiliary method for ::run(). Synopsis Event_scheduler::clean_queue() */ void Event_scheduler::clean_queue(THD *thd) { uint i; int ret; DBUG_ENTER("Event_scheduler::clean_queue"); pthread_mutex_lock(&LOCK_mutex); if (workers_count) { bool had_super= false; /* ToDo: This is a bit suboptimal because we try to kill everything, even non-running events. */ for (i= 0; i < workers.elements; ++i) DBUG_PRINT("info", ("working_thread#%d=%lu", i, *dynamic_element(&workers, i, ulong*))); /* We need temporarily SUPER_ACL to be able to kill our offsprings */ if (!(thd->security_ctx->master_access & SUPER_ACL)) thd->security_ctx->master_access|= SUPER_ACL; else had_super= true; for (i= 0; i < workers.elements; ++i) { sql_print_information("SCHEDULER: Killing worker thread %lu", *dynamic_element(&workers, i, ulong*)); if ((ret= kill_one_thread(thd, *dynamic_element(&workers, i, ulong*), false, true))) { sql_print_error("SCHEDULER: Error while killing code=%d", ret); break; } } if (!had_super) thd->security_ctx->master_access &= ~SUPER_ACL; DBUG_PRINT("info", ("thd->security_ctx & SUPER_ACL=%ld User=%s", thd->security_ctx->master_access & SUPER_ACL, thd->security_ctx->user)); sql_print_information("SCHEDULER: Waiting for worker threads to finish"); /* Do it in a loop against spurious wakeups */ if (!ret) do { DBUG_PRINT("info", ("workers_count=%d", workers_count)); pthread_cond_wait(&COND_last_worker_exit, &LOCK_mutex); } while (workers_count); } pthread_mutex_unlock(&LOCK_mutex); delete_dynamic(&workers); sql_print_information("SCHEDULER: Emptying the queue."); /* empty the queue */ for (i= 0; i < queue.elements; ++i) { Event_timed *et= (Event_timed *) queue_element(&queue, i); et->free_sp(); delete et; } resize_queue(&queue, 0); DBUG_VOID_RETURN; } /* Shutdowns the event scheduler Synopsis Event_scheduler::shutdown() mode Wait the events or kill them immediately Returns EVENT_OP_OK OK EVENT_OP_CANT_KILL Error during stopping of manager thread EVENT_OP_NOT_RUNNING Manager not working */ enum Event_scheduler::event_manager_op_code Event_scheduler::shutdown(enum event_drop_mode stop_mode) { int ret; THD *thd= current_thd; DBUG_ENTER("Event_scheduler::shutdown"); pthread_mutex_lock(&LOCK_mutex); CHECK_RUNNING(EVENT_OP_NOT_RUNNING); mode= MANAGER_SHUTDOWN; DBUG_PRINT("info", ("Manager thread has id %d", thread_id)); sql_print_information("SCHEDULER: Killing manager thread %lu", thread_id); /* Sending the COND_new_work to ::run() is a way to get this working without race conditions. If we use kill_one_thread() it will call THD::awake() and because in ::run() both THD::enter_cond()/::exit_cond() are used, THD::awake() will try to lock LOCK_mutex. If we unlock it before then the pthread_cond_signal(COND_shutdown) could be signaled in ::run() and we can miss the signal before we relock. A way is to use another mutex for this shutdown procedure but better not. */ pthread_cond_signal(&COND_new_work); /* Guarantee we don't catch spurious signals */ sql_print_information("SCHEDULER: Waiting the manager thread to reply"); while (mode != MANAGER_INIT) { DBUG_PRINT("info", ("Waiting for COND_shutdown from the manager thread." " Current value of mode is %d . workers_count=%d", mode, workers_count)); pthread_cond_wait(&COND_shutdown, &LOCK_mutex); } sql_print_information("SCHEDULER: Manager thread replied"); DBUG_PRINT("info", ("Manager thread has cleaned up. Set mode to INIT")); pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(EVENT_OP_OK); } /* Handles updates of @@event_scheduler Synopsis Event_scheduler::event_scheduler_var_update() Returns FALSE OK TRUE Error */ enum Event_scheduler::event_manager_op_code Event_scheduler::event_scheduler_var_update(my_bool new_value) { Event_scheduler *mgr; enum event_manager_op_code res; DBUG_ENTER("Event_scheduler::event_scheduler_var_update"); pthread_mutex_lock(&LOCK_manager); if (new_value == Event_scheduler::manager_working) { DBUG_PRINT("info", ("The new value is the same as the old")); pthread_mutex_unlock(&LOCK_manager); DBUG_RETURN(EVENT_OP_OK); } /* Don't use the traditional way like other static functions do, namely lock LOCK_manager. If we get lock on LOCK_manager and ston is NULL and if the new value for the variable is `true`, meaning we have to start the scheduler there is a deadlock because ::get_instance() locks also on LOCK_manager. Instead, just call ::get_instance() and it will create an object if it is not needed. If setting the value to */ pthread_mutex_unlock(&LOCK_manager); if (!(mgr= Event_scheduler::get_instance())) DBUG_RETURN(EVENT_OP_CANT_INIT); /* ::start()/::shutdown() will serialize the access. Both methods don't allow parallel execution in them. */ DBUG_PRINT("info", ("%s the manager", new_value? "starting":"stopping")); DBUG_RETURN(new_value? mgr->start():mgr->shutdown(EVENT_STOP_SYNC)); } /* Increments the number of running worker threads Synopsis Event_scheduler::workers_increment() thd_id Newly started thread's id NOTE The caller should have locked LOCK_mutex! */ void Event_scheduler::workers_increment(ulong thd_id) { DBUG_ENTER("Event_scheduler::workers_increment"); DBUG_PRINT("info", ("mode=%d", ston->mode)); DBUG_ASSERT(ston->mode == MANAGER_RUNNING); ++workers_count; DBUG_VOID_RETURN; } /* Decrements the number of running worker threads Synopsis Event_scheduler::workers_decrement() thd_id The id of the thread that finishes. Pass 0 if the thread id is not known because the thread refused to start (workers_decrement() failed after successful workers_increment() call). NOTE The caller should have locked LOCK_mutex! */ void Event_scheduler::workers_decrement(ulong thd_id) { DBUG_ENTER("Event_scheduler::workers_decrement"); if (mode == MANAGER_RUNNING || mode == MANAGER_SHUTDOWN) --workers_count; DBUG_PRINT("info", ("workers_count=%d", workers_count)); DBUG_VOID_RETURN; } /* Increments the number of running worker threads Synopsis Event_scheduler::register_worker_thread() thd_id The id of the thread that starts Returns EVENT_OP_OK Ok EVENT_OP_NOT_RUNNING Scheduler not working */ enum Event_scheduler::event_manager_op_code Event_scheduler::register_worker_thread(ulong thd_id) { enum Event_scheduler::event_manager_op_code ret= EVENT_OP_OK; DBUG_ENTER("Event_scheduler::register_worker_thread"); pthread_mutex_lock(&LOCK_manager); DBUG_ASSERT(ston); if (ston) { pthread_mutex_lock(&ston->LOCK_mutex); /* Don't call ston->workers_increment() because the count was already incremented before pthread_create() was called. */ DBUG_PRINT("info", ("Adding %lu to the list of running events", thd_id)); push_dynamic(&ston->workers, (gptr) &thd_id); pthread_mutex_unlock(&ston->LOCK_mutex); } else ret= EVENT_OP_NOT_RUNNING; pthread_mutex_unlock(&LOCK_manager); DBUG_RETURN(ret); } /* Decrements the number of running worker threads Synopsis Event_scheduler::deregister_worker_thread() thd_id The id of the thread that finishes Returns EVENT_OP_OK Ok EVENT_OP_NOT_RUNNING Scheduler not working Note If thd_id wasn't found no error is generated. Thus if register_worker_thread() has failed for some reason it's safe to call this method. */ enum Event_scheduler::event_manager_op_code Event_scheduler::deregister_worker_thread(ulong thd_id) { enum Event_scheduler::event_manager_op_code ret= EVENT_OP_OK; DBUG_ENTER("Event_scheduler::deregister_worker_thread"); pthread_mutex_lock(&LOCK_manager); DBUG_ASSERT(ston); if (ston) { pthread_mutex_lock(&ston->LOCK_mutex); ston->workers_decrement(thd_id); if (ston->mode == MANAGER_RUNNING || ston->mode == MANAGER_SHUTDOWN) { register uint i= 0; register ulong tid= thd_id; for (; i < ston->workers.elements; ++i) if (*dynamic_element(&ston->workers, i, ulong*) == tid) { delete_dynamic_element(&ston->workers, i); break; } } DBUG_PRINT("info", ("workers_count=%d workers.elements=%lu", ston->workers_count, ston->workers.elements)); if (ston->mode == MANAGER_SHUTDOWN && !ston->workers_count) { DBUG_PRINT("info", ("Sending out COND_last_worker_exit")); pthread_cond_signal(&ston->COND_last_worker_exit); } pthread_mutex_unlock(&ston->LOCK_mutex); } else ret= EVENT_OP_NOT_RUNNING; pthread_mutex_unlock(&LOCK_manager); DBUG_RETURN(ret); } /* Returns the number of elements in the queue Synopsis Event_scheduler::events_count() Returns -1 Manager not working >=0 Number of Event_timed objects in the queue */ int Event_scheduler::events_count() { int n; DBUG_ENTER("Event_scheduler::events_count"); pthread_mutex_lock(&LOCK_mutex); if (mode == MANAGER_RUNNING) n= queue.elements; else n= -1; pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(n); } /* Looks for a named event in mysql.event and then loads it from the table, compiles and inserts it into the cache. SYNOPSIS Event_scheduler::load_and_compile_event() thd THD etn The name of the event to load and compile on manager's root RETURN VALUE NULL Error during compile otherwise Address */ Event_timed * Event_scheduler::load_and_compile_event(THD *thd, Event_timed *etn) { int ret= 0; MEM_ROOT *tmp_mem_root; Event_timed *et_new; Open_tables_state backup; DBUG_ENTER("Event_scheduler::load_and_compile_event"); DBUG_PRINT("enter", ("name: %s", etn->name.str)); thd->reset_n_backup_open_tables_state(&backup); /* No need to use my_error() here because db_find_event() has done it */ { sp_name spn(etn->dbname, etn->name); ret= db_find_event(thd, &spn, &etn->definer, &et_new, NULL, &manager_root); } thd->restore_backup_open_tables_state(&backup); if (ret) DBUG_RETURN(NULL); et_new->compute_next_execution_time(); DBUG_RETURN(et_new); } /* Loads all ENABLED events from mysql.event into the prioritized queue. Called during scheduler main thread initialization. Compiles the events. Creates Event_timed instances for every ENABLED event from mysql.event. SYNOPSIS Event_scheduler::load_events_from_db() thd - Thread context. Used for memory allocation in some cases. RETURNS 0 OK !0 Error NOTES Reports the error to the console */ int Event_scheduler::load_events_from_db(THD *thd) { TABLE *table; READ_RECORD read_record_info; int ret= -1; uint count= 0; DBUG_ENTER("evex_load_events_from_db"); pthread_mutex_lock(&LOCK_mutex); if (mode > MANAGER_STARTING) { DBUG_ASSERT(0); sql_print_error("SCHEDULER: Trying to load events while already running."); pthread_mutex_unlock(&LOCK_mutex); DBUG_RETURN(EVEX_GENERAL_ERROR); } pthread_mutex_unlock(&LOCK_mutex); if ((ret= evex_open_event_table(thd, TL_READ, &table))) { sql_print_error("SCHEDULER: Table mysql.event is damaged. Can not open."); DBUG_RETURN(EVEX_OPEN_TABLE_FAILED); } init_read_record(&read_record_info, thd, table ,NULL,1,0); while (!(read_record_info.read_record(&read_record_info))) { Event_timed *et; if (!(et= new Event_timed)) { DBUG_PRINT("load_events_from_db", ("Out of memory")); ret= -1; goto end; } DBUG_PRINT("load_events_from_db", ("Loading event from row.")); if ((ret= et->load_from_row(&manager_root, table))) { sql_print_error("SCHEDULER: Error while loading from mysql.event. " "Table probably corrupted"); goto end; } if (et->status != MYSQL_EVENT_ENABLED) { DBUG_PRINT("load_events_from_db",("%s is disabled",et->name.str)); delete et; continue; } DBUG_PRINT("load_events_from_db", ("Event %s loaded from row. Time to compile", et->name.str)); switch (ret= et->compile(thd, &manager_root)) { case EVEX_MICROSECOND_UNSUP: sql_print_error("SCHEDULER: mysql.event is tampered. MICROSECOND is not " "supported but found in mysql.event"); goto end; case EVEX_COMPILE_ERROR: sql_print_error("SCHEDULER: Error while compiling %s.%s. Aborting load.", et->dbname.str, et->name.str); goto end; default: break; } /* let's find when to be executed */ if (et->compute_next_execution_time()) { sql_print_error("SCHEDULER: Error while computing execution time of %s.%s." " Skipping", et->dbname.str, et->name.str); continue; } DBUG_PRINT("load_events_from_db", ("Adding to the exec list.")); queue_insert_safe(&queue, (byte *) et); DBUG_PRINT("load_events_from_db", ("%p %*s", et, et->name.length,et->name.str)); count++; } ret= 0; end: end_read_record(&read_record_info); /* Force close to free memory */ thd->version--; close_thread_tables(thd); if (!ret) sql_print_information("SCHEDULER: Loaded %d event%s", count, (count == 1)?"":"s"); DBUG_PRINT("info", ("Status code %d. Loaded %d event(s)", ret, count)); DBUG_RETURN(ret); } /* Opens mysql.db and mysql.user and checks whether: 1. mysql.db has column Event_priv at column 20 (0 based); 2. mysql.user has column Event_priv at column 29 (0 based); Synopsis Event_scheduler::check_system_tables() */ void Event_scheduler::check_system_tables() { THD *thd= current_thd; TABLE_LIST tables; bool not_used; Open_tables_state backup; /* thd is 0x0 during boot of the server. Later it's !=0x0 */ if (!thd) return; thd->reset_n_backup_open_tables_state(&backup); bzero((char*) &tables, sizeof(tables)); tables.db= (char*) "mysql"; tables.table_name= tables.alias= (char*) "db"; tables.lock_type= TL_READ; if (simple_open_n_lock_tables(thd, &tables)) sql_print_error("Cannot open mysql.db"); else { table_check_intact(tables.table, MYSQL_DB_FIELD_COUNT, mysql_db_table_fields, &mysql_db_table_last_check,ER_CANNOT_LOAD_FROM_TABLE); close_thread_tables(thd); } bzero((char*) &tables, sizeof(tables)); tables.db= (char*) "mysql"; tables.table_name= tables.alias= (char*) "user"; tables.lock_type= TL_READ; if (simple_open_n_lock_tables(thd, &tables)) sql_print_error("Cannot open mysql.db"); else { if (tables.table->s->fields < 29 || strncmp(tables.table->field[29]->field_name, STRING_WITH_LEN("Event_priv"))) sql_print_error("mysql.user has no `Event_priv` column at position 29"); close_thread_tables(thd); } thd->restore_backup_open_tables_state(&backup); } #ifndef DBUG_OFF #define ERR_W_MSG(cond, msg) \ { \ sql_print_information("Testing %s", msg); \ DBUG_PRINT("info",("Testing %s", msg)); \ protocol->prepare_for_resend(); \ protocol->store(msg, strlen(msg), system_charset_info); \ if (!(cond)){ \ protocol->store((char*)STRING_WITH_LEN("ERROR"), system_charset_info); \ ret= protocol->write(); \ goto err; \ } else {\ protocol->store((char*)STRING_WITH_LEN("OK"), system_charset_info); \ ret= protocol->write(); \ if (ret) \ goto err; \ } \ } bool Event_scheduler::run_tests(THD *thd) { Protocol *protocol= thd->protocol; Event_scheduler *mgr; List field_list; int ret; struct timespec abstime; int exec_count=0; DBUG_ENTER("evex_manager_tester"); field_list.push_back(new Item_empty_string("Test", 100)); field_list.push_back(new Item_empty_string("Result", 5)); if (protocol->send_fields(&field_list, Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF)) DBUG_RETURN(true); Event_timed et; et.dbname.str= (char *)"test"; et.dbname.length= strlen("test"); et.name.str= (char *)"event_name"; et.name.length= strlen("event_name"); et.definer.str= (char *)"root@localhost"; et.definer.length= strlen("root@localhost"); et.body.str= (char *) "select 1 from dual"; et.body.length= strlen("select 1 from dual"); et.expression= 3; et.interval= INTERVAL_SECOND; et.ends_null= true; my_tz_UTC->gmt_sec_to_TIME(&et.starts, time(NULL) + 10); Event_timed et2; et2.dbname.str= (char *)"test"; et2.dbname.length= strlen("test"); et2.name.str= (char *)"event_name2"; et2.name.length= strlen("event_name2"); et2.definer.str= (char *)"root@localhost"; et2.definer.length= strlen("root@localhost"); et2.body.str= (char *) "select 2 from dual"; et2.body.length= strlen("select 2 from dual"); et2.expression= 5; et2.interval= INTERVAL_SECOND; et2.ends_null= true; my_tz_UTC->gmt_sec_to_TIME(&et2.starts, time(NULL) + 15); uint tmp; /* Force new manager instantiation */ ERR_W_MSG(!Event_scheduler::destroy(), "Destroy old manager"); ERR_W_MSG(!Event_scheduler::ston, "Old manager"); mgr= Event_scheduler::get_instance(); ERR_W_MSG(mgr, "Create new manager"); ERR_W_MSG((mgr->mode == Event_scheduler::MANAGER_INIT), "Test manager mode "); ERR_W_MSG(mgr->events_count() == -1, "Test count"); ERR_W_MSG(!db_create_event(thd, &et, false, &tmp), "Create event on disk"); ERR_W_MSG(!mgr->start(), "Start manager"); mgr->add_event(thd, &et, false); ERR_W_MSG(mgr->events_count() == 2, "Test count wo check"); mgr->add_event(thd, &et, true); ERR_W_MSG(mgr->events_count() == 2, "Test count with check"); mgr->add_event(thd, &et, false); ERR_W_MSG(mgr->events_count() == 3, "Test count wo check"); mgr->add_event(thd, &et2, true); ERR_W_MSG(mgr->events_count() == 3, "Test count after add of et2"); ERR_W_MSG(!db_create_event(thd, &et2, false, &tmp), "Create event et2 on disk"); mgr->add_event(thd, &et2, true); ERR_W_MSG(mgr->events_count() == 4, "Test count after add of et2 (again)"); mgr->drop_event(thd, &et, Event_scheduler::EVENT_STOP_SYNC); ERR_W_MSG(mgr->events_count() == 3, "Test delete 1"); mgr->drop_event(thd, &et, Event_scheduler::EVENT_STOP_SYNC); ERR_W_MSG(mgr->events_count() == 2, "Test delete 2"); mgr->drop_event(thd, &et, Event_scheduler::EVENT_STOP_SYNC); ERR_W_MSG(mgr->events_count() == 1, "Test delete 3"); et2.body.str= (char *) "select 212 from dual"; et2.body.length= strlen("select 212 from dual"); mgr->replace_event(thd, &et2, Event_scheduler::EVENT_STOP_SYNC); ERR_W_MSG(mgr->events_count() == 1, "Test delete 4"); /* Here we will get an empty line because kill_one_thread() which is used by ::shutdown() calls send_eof(). */ ERR_W_MSG(!mgr->shutdown(EVENT_STOP_SYNC), "Shutdown the manager"); ERR_W_MSG(!et.drop(thd), "et.drop()"); ERR_W_MSG(!et2.drop(thd), "et2.drop()"); /* New test starting */ ERR_W_MSG(!mgr->start(), "Start manager again and sleep 2s"); ERR_W_MSG(mgr->start()== Event_scheduler::EVENT_OP_ALREADY_RUNNING, "Try to start again"); pthread_mutex_lock(&mgr->LOCK_executed); ERR_W_MSG(!db_create_event(thd, &et, false, &tmp), "Disk Create event et1"); ERR_W_MSG(!db_create_event(thd, &et2, false, &tmp),"Disk Create event et2"); ERR_W_MSG(!mgr->add_event(thd, &et, true), "Add et to the queue, step 1"); ERR_W_MSG(mgr->events_count() == 1, "Add et to queue, step 2"); ERR_W_MSG(!mgr->add_event(thd, &et2, true), "Add et2 to the queue, step 1"); ERR_W_MSG(mgr->events_count() == 2, "Add et2 to the queue, step 2"); /* now there should be 2 events */ /* 16 sec test */ abstime.tv_nsec= 0; abstime.tv_sec= time(NULL) + 13; while (ETIMEDOUT != pthread_cond_timedwait(&mgr->COND_executed, &mgr->LOCK_executed, &abstime)) { exec_count++; sql_print_information("Exec_count=%d", exec_count); } pthread_mutex_unlock(&mgr->LOCK_executed); sql_print_information("Exec_count=%d", exec_count); ERR_W_MSG(exec_count == 8, "Execution count"); /* Here we will get an empty line because kill_one_thread() which is used by ::shutdown() calls send_eof(). */ ERR_W_MSG(!mgr->shutdown(EVENT_STOP_SYNC), "Shutdown manager"); ERR_W_MSG(mgr->shutdown(EVENT_STOP_SYNC)== Event_scheduler::EVENT_OP_NOT_RUNNING, "Shutdown manager again for checking"); ERR_W_MSG(!Event_scheduler::destroy(), "Destroy new manager"); ERR_W_MSG(!Event_scheduler::ston, "Singleton"); ERR_W_MSG(!et.drop(thd), "et.drop()"); ERR_W_MSG(!et2.drop(thd), "et2.drop()"); ERR_W_MSG(TRUE, "All Tests"); send_eof(thd); DBUG_RETURN(false); err: mgr->shutdown(EVENT_STOP_SYNC); Event_scheduler::destroy(); send_eof(thd); DBUG_RETURN(true); } #endif --- New file --- +++ sql/event_scheduler.h 06/04/04 22:41:48 #ifndef _EVENT_MANAGER_H_ #define _EVENT_MANAGER_H_ class THD; /* Locking hierarchy: ->LOCK_executed (used for counting of forks together with COND_executed) ->LOCK_manager --->LOCK_mutex (protects `mode`) ----->LOCK_workers_count (protects `workers_count`) ----->LOCK_last_worker_exit (for COND_last_worker_exit) */ class Event_scheduler { public: /* This mutex is public so we can initialize it during server startup. The reason to initialize it there is that we use singleton and this mutex guards creation and destruction of the singleton object. */ static pthread_mutex_t LOCK_manager; /* Storage for @@event_scheduler */ static my_bool manager_working; /* SYNC or ASYNC stop of running events */ enum event_drop_mode { EVENT_STOP_ASYNC = 1, EVENT_STOP_SYNC =2 }; /* The life cycle of a manager */ enum event_manager_mode { MANAGER_INIT= 0, MANAGER_STARTING, MANAGER_CANTSTART, MANAGER_RUNNING, MANAGER_SHUTDOWN, MANAGER_STOPPED, }; /* Return codes */ enum event_manager_op_code { EVENT_OP_OK= 0, EVENT_OP_CANTFORK, EVENT_OP_CANTSTART, EVENT_OP_ALREADY_RUNNING, EVENT_OP_NOT_RUNNING, EVENT_OP_CANT_KILL, EVENT_OP_CANT_INIT }; /* Singleton access */ static Event_scheduler* get_instance(); bool add_event(THD *thd, Event_timed *et, bool check_existance); bool drop_event(THD *thd, Event_timed *etn, enum event_drop_mode drop_mode); bool replace_event(THD *thd, Event_timed *et, enum event_drop_mode replace_mode); /* LOCKING PROTOCOL: Does not do any locking. The caller is responsible to lock and signal. */ Event_timed * find_event(Event_timed *etn, bool remove_from_q); bool trigger_event(THD *thd, Event_timed *etn) { DBUG_ASSERT(0);} int events_count(); enum event_manager_op_code start(); bool run(THD *thd); enum event_manager_op_code shutdown(enum event_drop_mode stop_mode); /* Call this only at the end of the server. */ static bool destroy() { pthread_mutex_lock(&LOCK_manager); if (ston && ston->mode == MANAGER_RUNNING) { /* the master thread should not be running */ DBUG_ASSERT(0); return true; } delete ston; ston= NULL; pthread_mutex_unlock(&LOCK_manager); return false; } static enum event_manager_op_code event_scheduler_var_update(my_bool new_value); static enum event_manager_op_code register_worker_thread(ulong thd_id); static enum event_manager_op_code deregister_worker_thread(ulong thd_id); #ifndef DBUG_OFF static bool run_tests(THD *thd); pthread_cond_t COND_executed; pthread_mutex_t LOCK_executed; #endif protected: void workers_increment(ulong thd_id); void workers_decrement(ulong thd_id); /* helper functions */ bool execute_top(THD *thd); void clean_queue(THD *thd); static void check_system_tables(); Event_timed * load_and_compile_event(THD *thd, Event_timed *etn); int load_events_from_db(THD *thd); private: /* Prevent use of these */ Event_scheduler(const Event_scheduler &); void operator=(Event_scheduler &); /* Singleton is used */ Event_scheduler():thread_id(0), workers_count(0) {} /* LOCK PROCOTOL: Expects that this method is synchronized */ ~Event_scheduler() { /* ToDo: Wait if there are elements on the queue */ pthread_mutex_lock(&LOCK_mutex); ston->mode= MANAGER_SHUTDOWN; pthread_mutex_unlock(&LOCK_mutex); delete_queue(&queue); pthread_cond_destroy(&COND_new_work); pthread_cond_destroy(&COND_started); #ifndef DBUG_OFF pthread_cond_destroy(&COND_executed); pthread_mutex_destroy(&LOCK_executed); #endif mode= MANAGER_STOPPED; pthread_mutex_destroy(&LOCK_mutex); } /* Singleton instance */ static Event_scheduler *ston; /* This is the current status of the life-cycle of the manager. */ enum event_manager_mode mode; /* LOCK_mutex is the mutex which protects the access to the manager's queue as well as used when signalling COND_new_work, COND_started and COND_shutdown. */ pthread_mutex_t LOCK_mutex; pthread_mutex_t LOCK_last_worker_exit; /* Holds the thread id of the executor thread or 0 if the executor is not running. It is used by ::shutdown() to know which thread to kill with kill_one_thread(). The latter wake ups a thread if it is waiting on a conditional variable and sets thd->killed to non-zero. */ ulong thread_id; /* COND_new_work is a conditional used to signal that there is a change of the queue that should inform the executor thread that new event should be executed sooner than previously expected, because of add/replace event. */ pthread_cond_t COND_new_work; /* COND_started is a conditional used to synchronize the thread in which ::start() was called and the spawned thread. ::start() spawns a new thread and then waits on COND_started but also checks when awaken that `mode` is either MODE_RUNNING or MODE_CANTSTART. Then it returns back. */ pthread_cond_t COND_started; /* COND_shutdown is a conditional very similar to COND_started in it usage but is used during ::shutdown() call. ::shutdown() kills the executor thread and then waits for COND_shutdown to be signalled by the latter. When this happens and `mode` is set back by the executor thread to MODE_INIT, to guarantee protection against spurious wake-ups, ::shutdown() returns. */ pthread_cond_t COND_shutdown; /* COND_last_worker_exit is a conditional signaled by a worker thread when the workers_count reaches 0. This notifies the manager thread that it shoud continue with the clean up. */ pthread_cond_t COND_last_worker_exit; MEM_ROOT manager_root; QUEUE queue; /* Number of running threads. It can differ from workers.elements because workers_count is incremented before forking of a new thread to prevent the following race condition: 1. Thread forked (and stops) 2. Manager shutdown and does not see the forked thread because it hasn't called ::register_worker_thread() and frees the Event_timed object 3. The forked thread tries to access the Event_timed object */ int workers_count; /* DYNAMIC_ARRAY which holds the id of the threads which are spawned, so we can kill them during shutdown. Hence, no need to go over the whole list of events in memory and ask everyone to kill itself, if running. Additional gain is that an event can be run, with this code, in more than one threads but in every thread the sp_head has to be compiled again, because it's not reentrant and is tightly coupled to class THD. */ DYNAMIC_ARRAY workers; }; #endif /* _EVENT_MANAGER_H_ */ --- 1.47/sql/event_timed.cc 2006-03-17 09:36:32 +01:00 +++ 1.48/sql/event_timed.cc 2006-04-04 22:41:46 +02:00 @@ -927,6 +927,9 @@ Event_timed::compute_next_execution_time goto ret; } ret: + sql_print_information("SCHEDULER: Next execution at [%04d-%02d-%02d %02d:%02d:%02d UTC]", + execute_at.year, execute_at.month, execute_at.day, + execute_at.hour, execute_at.minute, execute_at.second); DBUG_RETURN(false); err: @@ -1545,4 +1548,21 @@ Event_timed::spawn_unlock(THD *thd) } VOID(pthread_mutex_unlock(&this->LOCK_running)); return ret; +} + + +/* + Kills a running event + Synopsis + Event_timed::kill_thread() + + Returns + 0 OK + !0 Error +*/ + +int +Event_timed::kill_thread() +{ + return false; } --- 1.180/sql/set_var.cc 2006-03-21 10:54:21 +01:00 +++ 1.181/sql/set_var.cc 2006-04-04 22:41:47 +02:00 @@ -221,9 +221,11 @@ sys_var_long_ptr sys_delayed_insert_time &delayed_insert_timeout); sys_var_long_ptr sys_delayed_queue_size("delayed_queue_size", &delayed_queue_size); + +#include "event_scheduler.h" sys_var_event_executor sys_event_executor("event_scheduler", (my_bool *) - &event_executor_running_global_var); + &Event_scheduler::manager_working); sys_var_long_ptr sys_expire_logs_days("expire_logs_days", &expire_logs_days); sys_var_bool_ptr sys_flush("flush", &myisam_flush);