gcc/libcilkrts/include/cilktools/fake_mutex.h

93 lines
2.9 KiB
C++

/* fake_mutex.h -*-C++-*-
*
*************************************************************************
*
* @copyright
* Copyright (C) 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.
*
**************************************************************************
*
* Cilkscreen fake mutexes are provided to indicate to the Cilkscreen race
* detector that a race should be ignored.
*
* NOTE: This class does not provide mutual exclusion. You should use the
* mutual exclusion constructs provided by TBB or your operating system to
* protect against real data races.
*/
#ifndef FAKE_MUTEX_H_INCLUDED
#define FAKE_MUTEX_H_INCLUDED
#include <cilktools/cilkscreen.h>
namespace cilkscreen
{
class fake_mutex
{
public:
fake_mutex() : locked(false)
{
}
~fake_mutex()
{
__CILKRTS_ASSERT(! locked);
}
// Wait until mutex is available, then enter
void lock()
{
__cilkscreen_acquire_lock(&locked);
__CILKRTS_ASSERT(! locked);
locked = true;
}
// A fake mutex is always available
bool try_lock() { lock(); return true; }
// Releases the mutex
void unlock()
{
__CILKRTS_ASSERT(locked);
locked = false;
__cilkscreen_release_lock(&locked);
}
private:
bool locked;
};
} // namespace cilk
#endif // FAKE_MUTEX_H_INCLUDED