Retro68/gcc/libcilkrts/runtime/worker_mutex.h
2014-09-21 19:33:12 +02:00

132 lines
4.2 KiB
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/* worker_mutex.h -*-C++-*-
*
*************************************************************************
*
* @copyright
* Copyright (C) 2009-2013, Intel Corporation
* All rights reserved.
*
* @copyright
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* @copyright
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
* WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
**************************************************************************/
/**
* @file worker_mutex.h
*
* @brief Support for Cilk runtime mutexes.
*
* Cilk runtime mutexes are implemented as simple spin loops.
*/
#ifndef INCLUDED_WORKER_MUTEX_DOT_H
#define INCLUDED_WORKER_MUTEX_DOT_H
#include <cilk/common.h>
#include "rts-common.h"
__CILKRTS_BEGIN_EXTERN_C
/**
* Mutexes are treated as an abstract data type within the Cilk
* runtime system. They are implemented as simple spin loops and
* owned by a __cilkrts_worker.
*/
typedef struct mutex {
/** Mutex spin loop variable. 0 if unowned, 1 if owned. */
volatile int lock;
/** Worker that owns the mutex. Must be 0 if mutex is unowned. */
__cilkrts_worker *owner;
} mutex;
/**
* @brief Initialize a Cilk mutex.
*
* @param m Mutex to be initialized.
*/
COMMON_PORTABLE
void __cilkrts_mutex_init(struct mutex *m);
/**
* @brief Acquire a Cilk mutex.
*
* If statistics are being gathered, the time spent
* acquiring the mutex will be attributed to the specified worker.
*
* @param w Worker that will become the owner of this mutex.
* @param m Mutex to be initialized.
*/
COMMON_PORTABLE
void __cilkrts_mutex_lock(__cilkrts_worker *w,
struct mutex *m);
/**
* @brief Attempt to lock a Cilk mutex and fail if it isn't available.
*
* If statistics are being gathered, the time spent acquiring the
* mutex will be attributed to the specified worker.
*
* @param w Worker that will become the owner of this mutex.
* @param m Mutex to be acquired.
*
* @return 1 if the mutex was acquired.
* @return 0 if the mutex was not acquired.
*/
COMMON_PORTABLE
int __cilkrts_mutex_trylock(__cilkrts_worker *w,
struct mutex *m);
/**
* @brief Release a Cilk mutex.
*
* If statistics are being gathered, the time spent
* acquiring the mutex will be attributed to the specified worker.
*
* @pre The mutex must be owned by the worker.
*
* @param w Worker that owns this mutex.
* @param m Mutex to be released.
*/
COMMON_PORTABLE
void __cilkrts_mutex_unlock(__cilkrts_worker *w,
struct mutex *m);
/**
* @brief Deallocate a Cilk mutex. Currently does nothing.
*
* @param w Unused.
* @param m Mutex to be deallocated.
*/
COMMON_PORTABLE
void __cilkrts_mutex_destroy(__cilkrts_worker *w,
struct mutex *m);
__CILKRTS_END_EXTERN_C
#endif // ! defined(INCLUDED_WORKER_MUTEX_DOT_H)