darling-WTF/wtf/ParallelJobsLibdispatch.h
2017-08-12 09:27:19 -07:00

74 lines
2.6 KiB
C++

/*
* Copyright (C) 2011 University of Szeged
* Copyright (C) 2011 Gabor Loki <loki@webkit.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY UNIVERSITY OF SZEGED ``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 UNIVERSITY OF SZEGED 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.
*/
#ifndef ParallelJobsLibdispatch_h
#define ParallelJobsLibdispatch_h
#if ENABLE(THREADING_LIBDISPATCH)
#include <dispatch/dispatch.h>
namespace WTF {
class ParallelEnvironment {
WTF_MAKE_FAST_ALLOCATED;
public:
typedef void (*ThreadFunction)(void*);
ParallelEnvironment(ThreadFunction threadFunction, size_t sizeOfParameter, int requestedJobNumber)
: m_threadFunction(threadFunction)
, m_sizeOfParameter(sizeOfParameter)
, m_numberOfJobs(requestedJobNumber)
{
// We go with the requested number of jobs. libdispatch will distribute the work optimally.
ASSERT_ARG(requestedJobNumber, requestedJobNumber > 0);
}
int numberOfJobs()
{
return m_numberOfJobs;
}
void execute(unsigned char* parameters)
{
static dispatch_queue_t globalQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_apply(m_numberOfJobs, globalQueue, ^(size_t i) { (*m_threadFunction)(parameters + (m_sizeOfParameter * i)); });
}
private:
ThreadFunction m_threadFunction;
size_t m_sizeOfParameter;
int m_numberOfJobs;
};
} // namespace WTF
#endif // ENABLE(THREADING_LIBDISPATCH)
#endif // ParallelJobsLibdispatch_h