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diff --git a/storage/innobase/include/srv0conc.h b/storage/innobase/include/srv0conc.h
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+/*****************************************************************************
+
+Copyright (c) 2011, Oracle and/or its affiliates. All Rights Reserved.
+
+Portions of this file contain modifications contributed and copyrighted by
+Google, Inc. Those modifications are gratefully acknowledged and are described
+briefly in the InnoDB documentation. The contributions by Google are
+incorporated with their permission, and subject to the conditions contained in
+the file COPYING.Google.
+
+Portions of this file contain modifications contributed and copyrighted
+by Percona Inc.. Those modifications are
+gratefully acknowledged and are described briefly in the InnoDB
+documentation. The contributions by Percona Inc. are incorporated with
+their permission, and subject to the conditions contained in the file
+COPYING.Percona.
+
+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 Street, Suite 500, Boston, MA 02110-1335 USA
+
+*****************************************************************************/
+
+/**************************************************//**
+@file srv/srv0conc.h
+
+InnoDB concurrency manager header file
+
+Created 2011/04/18 Sunny Bains
+*******************************************************/
+
+#ifndef srv_conc_h
+#define srv_conc_h
+
+/** We are prepared for a situation that we have this many threads waiting for
+a semaphore inside InnoDB. innobase_start_or_create_for_mysql() sets the
+value. */
+
+extern	ulint	srv_max_n_threads;
+
+/** The following controls how many threads we let inside InnoDB concurrently:
+threads waiting for locks are not counted into the number because otherwise
+we could get a deadlock. Value of 0 will disable the concurrency check. */
+
+extern ulong	srv_thread_concurrency;
+
+/*********************************************************************//**
+Initialise the concurrency management data structures */
+void
+srv_conc_init(void);
+/*===============*/
+
+/*********************************************************************//**
+Free the concurrency management data structures */
+void
+srv_conc_free(void);
+/*===============*/
+
+/*********************************************************************//**
+Puts an OS thread to wait if there are too many concurrent threads
+(>= srv_thread_concurrency) inside InnoDB. The threads wait in a FIFO queue. */
+UNIV_INTERN
+void
+srv_conc_enter_innodb(
+/*==================*/
+	trx_t*	trx);		/*!< in: transaction object associated
+				with the thread */
+
+/*********************************************************************//**
+This lets a thread enter InnoDB regardless of the number of threads inside
+InnoDB. This must be called when a thread ends a lock wait. */
+UNIV_INTERN
+void
+srv_conc_force_enter_innodb(
+/*========================*/
+	trx_t*	trx);		/*!< in: transaction object associated with
+				the thread */
+
+/*********************************************************************//**
+This must be called when a thread exits InnoDB in a lock wait or at the
+end of an SQL statement. */
+UNIV_INTERN
+void
+srv_conc_force_exit_innodb(
+/*=======================*/
+	trx_t*	trx);		/*!< in: transaction object associated with
+				the thread */
+
+/*********************************************************************//**
+Get the count of threads waiting inside InnoDB. */
+UNIV_INTERN
+ulint
+srv_conc_get_waiting_threads(void);
+/*==============================*/
+
+/*********************************************************************//**
+Get the count of threads active inside InnoDB. */
+UNIV_INTERN
+ulint
+srv_conc_get_active_threads(void);
+/*==============================*/
+
+#endif /* srv_conc_h */