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+/* Copyright (c) 2007, 2013, Oracle and/or its affiliates.
+ Copyright (c) 2012, 2014, SkySQL 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 02110-1335 USA */
+
+/*
+ Implementation for the thread scheduler
+*/
+
+#ifdef USE_PRAGMA_INTERFACE
+#pragma implementation
+#endif
+
+#include "mariadb.h"
+#include "mysqld.h"
+#include "scheduler.h"
+#include "sql_class.h"
+#include "sql_callback.h"
+#include <violite.h>
+
+/** @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,
+ Atomic_counter<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->add_connection= create_thread_to_handle_connection;
+ func->post_kill_notification= post_kill_notification;
+}
+#else
+void handle_connection_in_main_thread(CONNECT *connect)
+{
+}
+#endif
+
+/*
+ Initialize scheduler for --thread-handling=no-threads
+*/
+
+void one_thread_scheduler(scheduler_functions *func,
+ Atomic_counter<uint> *arg_connection_count)
+{
+ scheduler_init();
+ func->max_threads= 1;
+ func->max_connections= &max_connections;
+ func->connection_count= arg_connection_count;
+ func->add_connection= handle_connection_in_main_thread;
+}