diff options
Diffstat (limited to 'sql/scheduler.cc')
| -rw-r--r-- | sql/scheduler.cc | 162 |
1 files changed, 126 insertions, 36 deletions
diff --git a/sql/scheduler.cc b/sql/scheduler.cc index 10009246428..19f8ddc7355 100644 --- a/sql/scheduler.cc +++ b/sql/scheduler.cc @@ -25,55 +25,98 @@ #include "unireg.h" // REQUIRED: for other includes #include "scheduler.h" #include "sql_connect.h" // init_new_connection_handler_thread +#include "scheduler.h" +#include "sql_callback.h" /* - 'Dummy' functions to be used when we don't need any handling for a scheduler - event - */ + End connection, in case when we are using 'no-threads' +*/ -static bool init_dummy(void) {return 0;} -static void post_kill_dummy(THD* thd) {} -static void end_dummy(void) {} -static bool end_thread_dummy(THD *thd, bool cache_thread) { return 0; } +static bool no_threads_end(THD *thd, bool put_in_cache) +{ + unlink_thd(thd); + mysql_mutex_unlock(&LOCK_thread_count); + return 1; // Abort handle_one_connection +} -/* - Initialize default scheduler with dummy functions so that setup functions - only need to declare those that are relvant for their usage +static scheduler_functions one_thread_scheduler_functions= +{ + 1, // max_threads + NULL, // init + init_new_connection_handler_thread, // init_new_connection_thread + handle_connection_in_main_thread, // add_connection + NULL, // thd_wait_begin + NULL, // thd_wait_end + NULL, // post_kill_notification + no_threads_end, // end_thread + NULL, // end +}; + +static scheduler_functions one_thread_per_connection_scheduler_functions= +{ + 0, // max_threads + NULL, // init + init_new_connection_handler_thread, // init_new_connection_thread + create_thread_to_handle_connection, // add_connection + NULL, // thd_wait_begin + NULL, // thd_wait_end + NULL, // post_kill_notification + one_thread_per_connection_end, // end_thread + NULL, // end +}; + + +scheduler_functions *thread_scheduler= + &one_thread_per_connection_scheduler_functions; + +/** @internal + Helper functions to allow mysys to call the thread scheduler when + waiting for locks. */ -scheduler_functions::scheduler_functions() - :init(init_dummy), - init_new_connection_thread(init_new_connection_handler_thread), - add_connection(0), // Must be defined - post_kill_notification(post_kill_dummy), - end_thread(end_thread_dummy), end(end_dummy) -{} +/**@{*/ +static void scheduler_wait_begin(void) { + MYSQL_CALLBACK(thread_scheduler, + thd_wait_begin, (current_thd, THD_WAIT_ROW_TABLE_LOCK)); +} +static void scheduler_wait_end(void) { + MYSQL_CALLBACK(thread_scheduler, thd_wait_end, (current_thd)); +} +/**@}*/ + +/** + Common scheduler init function. + + The scheduler is either initialized by calling + one_thread_scheduler() or one_thread_per_connection_scheduler() in + mysqld.cc, so this init function will always be called. + */ +static void scheduler_init() { + thr_set_lock_wait_callback(scheduler_wait_begin, scheduler_wait_end); +} /* - End connection, in case when we are using 'no-threads' + Initialize scheduler for --thread-handling=one-thread-per-connection */ -static bool no_threads_end(THD *thd, bool put_in_cache) +#ifndef EMBEDDED_LIBRARY +void one_thread_per_connection_scheduler() { - unlink_thd(thd); - mysql_mutex_unlock(&LOCK_thread_count); - return 1; // Abort handle_one_connection + scheduler_init(); + one_thread_per_connection_scheduler_functions.max_threads= max_connections; + thread_scheduler= &one_thread_per_connection_scheduler_functions; } - +#endif /* Initailize scheduler for --thread-handling=no-threads */ -void one_thread_scheduler(scheduler_functions* func) +void one_thread_scheduler() { - func->max_threads= 1; -#ifndef EMBEDDED_LIBRARY - func->add_connection= handle_connection_in_main_thread; -#endif - func->init_new_connection_thread= init_dummy; - func->end_thread= no_threads_end; + scheduler_init(); + thread_scheduler= &one_thread_scheduler_functions; } @@ -81,11 +124,58 @@ void one_thread_scheduler(scheduler_functions* func) Initialize scheduler for --thread-handling=one-thread-per-connection */ -#ifndef EMBEDDED_LIBRARY -void one_thread_per_connection_scheduler(scheduler_functions* func) +/* + thd_scheduler keeps the link between THD and events. + It's embedded in the THD class. +*/ + +thd_scheduler::thd_scheduler() + : m_psi(NULL), data(NULL) { - func->max_threads= max_connections; - func->add_connection= create_thread_to_handle_connection; - func->end_thread= one_thread_per_connection_end; +#ifndef DBUG_OFF + dbug_explain[0]= '\0'; + set_explain= FALSE; +#endif } -#endif /* EMBEDDED_LIBRARY */ + + +thd_scheduler::~thd_scheduler() +{ +} + +static scheduler_functions *saved_thread_scheduler; +static uint saved_thread_handling; + +extern "C" +int my_thread_scheduler_set(scheduler_functions *scheduler) +{ + DBUG_ASSERT(scheduler != 0); + + if (scheduler == NULL) + return 1; + + saved_thread_scheduler= thread_scheduler; + saved_thread_handling= thread_handling; + thread_scheduler= scheduler; + // Scheduler loaded dynamically + thread_handling= SCHEDULER_TYPES_COUNT; + return 0; +} + + +extern "C" +int my_thread_scheduler_reset() +{ + DBUG_ASSERT(saved_thread_scheduler != NULL); + + if (saved_thread_scheduler == NULL) + return 1; + + thread_scheduler= saved_thread_scheduler; + thread_handling= saved_thread_handling; + saved_thread_scheduler= 0; + return 0; +} + + + |