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diff --git a/include/mysql/service_thd_wait.h b/include/mysql/service_thd_wait.h
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+/* Copyright (C) 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
+   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+#ifndef MYSQL_SERVICE_THD_WAIT_INCLUDED
+#define MYSQL_SERVICE_THD_WAIT_INCLUDED
+
+/**
+  @file include/mysql/service_thd_wait.h
+  This service provides functions for plugins and storage engines to report
+  when they are going to sleep/stall.
+  
+  SYNOPSIS
+  thd_wait_begin() - call just before a wait begins
+  thd                     Thread object
+                          Use NULL if the thd is NOT known.
+  wait_type               Type of wait
+                          1 -- short wait (e.g. for mutex)
+                          2 -- medium wait (e.g. for disk io)
+                          3 -- large wait (e.g. for locked row/table)
+  NOTES
+    This is used by the threadpool to have better knowledge of which
+    threads that currently are actively running on CPUs. When a thread
+    reports that it's going to sleep/stall, the threadpool scheduler is
+    free to start another thread in the pool most likely. The expected wait
+    time is simply an indication of how long the wait is expected to
+    become, the real wait time could be very different.
+
+  thd_wait_end() called immediately after the wait is complete
+
+  thd_wait_end() MUST be called if thd_wait_begin() was called.
+
+  Using thd_wait_...() service is optional but recommended.  Using it will
+  improve performance as the thread pool will be more active at managing the
+  thread workload.
+*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum _thd_wait_type_e {
+  THD_WAIT_MUTEX= 1,
+  THD_WAIT_DISKIO= 2,
+  THD_WAIT_ROW_TABLE_LOCK= 3,
+  THD_WAIT_GLOBAL_LOCK= 4
+} thd_wait_type;
+
+extern struct thd_wait_service_st {
+  void (*thd_wait_begin_func)(MYSQL_THD, thd_wait_type);
+  void (*thd_wait_end_func)(MYSQL_THD);
+} *thd_wait_service;
+
+#ifdef MYSQL_DYNAMIC_PLUGIN
+
+#define thd_wait_begin(_THD, _WAIT_TYPE) \
+  thd_wait_service->thd_wait_begin_func(_THD, _WAIT_TYPE)
+#define thd_wait_end(_THD) thd_wait_service->thd_wait_end_func(_THD)
+
+#else
+
+void thd_wait_begin(MYSQL_THD thd, thd_wait_type wait_type);
+void thd_wait_end(MYSQL_THD thd);
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+