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Diffstat (limited to 'sql/scheduler.cc')
| -rw-r--r-- | sql/scheduler.cc | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/sql/scheduler.cc b/sql/scheduler.cc new file mode 100644 index 00000000000..ecf49e633ab --- /dev/null +++ b/sql/scheduler.cc @@ -0,0 +1,153 @@ +/* Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved. + Copyright (c) 2012, 2013, Monty Program 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; version 2 of the License. + + 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ + +/* + Implementation for the thread scheduler +*/ + +#ifdef USE_PRAGMA_INTERFACE +#pragma implementation +#endif + +#include "sql_connect.h" // init_new_connection_handler_thread +#include "scheduler.h" +#include "mysqld.h" +#include "sql_class.h" +#include "sql_callback.h" +#include <violite.h> + +/* + End connection, in case when we are using 'no-threads' +*/ + +static bool no_threads_end(THD *thd, bool put_in_cache) +{ + unlink_thd(thd); + return 1; // Abort handle_one_connection +} + +/** @internal + Helper functions to allow mysys to call the thread scheduler when + waiting for locks. +*/ + +/**@{*/ +extern "C" +{ +static void scheduler_wait_lock_begin(void) { + thd_wait_begin(NULL, THD_WAIT_TABLE_LOCK); +} + +static void scheduler_wait_lock_end(void) { + thd_wait_end(NULL); +} + +static void scheduler_wait_sync_begin(void) { + thd_wait_begin(NULL, THD_WAIT_SYNC); +} + +static void scheduler_wait_sync_end(void) { + thd_wait_end(NULL); +} + +static void scheduler_wait_net_begin(void) { + thd_wait_begin(NULL, THD_WAIT_NET); +} + +static void scheduler_wait_net_end(void) { + thd_wait_end(NULL); +} + +}; +/**@}*/ + +/** + 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. + */ +void scheduler_init() { + thr_set_lock_wait_callback(scheduler_wait_lock_begin, + scheduler_wait_lock_end); + thr_set_sync_wait_callback(scheduler_wait_sync_begin, + scheduler_wait_sync_end); + + vio_set_wait_callback(scheduler_wait_net_begin, + scheduler_wait_net_end); +} + + +/** + Kill notification callback, used by one-thread-per-connection + and threadpool scheduler. + + Wakes up a thread that is stuck in read/poll/epoll/event-poll + routines used by threadpool, such that subsequent attempt to + read from client connection will result in IO error. +*/ + +void post_kill_notification(THD *thd) +{ + DBUG_ENTER("post_kill_notification"); + if (current_thd == thd || thd->system_thread) + DBUG_VOID_RETURN; + + if (thd->net.vio) + vio_shutdown(thd->net.vio, SHUT_RD); + DBUG_VOID_RETURN; +} + +/* + Initialize scheduler for --thread-handling=one-thread-per-connection +*/ + +#ifndef EMBEDDED_LIBRARY + + +void one_thread_per_connection_scheduler(scheduler_functions *func, + ulong *arg_max_connections, + uint *arg_connection_count) +{ + scheduler_init(); + func->max_threads= *arg_max_connections + 1; + func->max_connections= arg_max_connections; + func->connection_count= arg_connection_count; + func->init_new_connection_thread= init_new_connection_handler_thread; + func->add_connection= create_thread_to_handle_connection; + func->end_thread= one_thread_per_connection_end; + func->post_kill_notification= post_kill_notification; +} +#endif + +/* + Initailize scheduler for --thread-handling=no-threads +*/ + +void one_thread_scheduler(scheduler_functions *func) +{ + scheduler_init(); + func->max_threads= 1; + func->max_connections= &max_connections; + func->connection_count= &connection_count; +#ifndef EMBEDDED_LIBRARY + func->init_new_connection_thread= init_new_connection_handler_thread; + func->add_connection= handle_connection_in_main_thread; +#endif + func->end_thread= no_threads_end; +} + |