[apple/javascriptcore.git] / wtf / ParallelJobsLibdispatch.h

/*
 * 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 {

static const int maxParallelThreads = 2;

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)
    {
        if (!requestedJobNumber || requestedJobNumber > maxParallelThreads)
            requestedJobNumber = maxParallelThreads;

        ASSERT(requestedJobNumber > 0);

        m_numberOfJobs = requestedJobNumber;
    }

    int numberOfJobs()
    {
        return m_numberOfJobs;
    }

    void execute(unsigned char* parameters)
    {
        // libdispatch is NOT supported inside a template
        dispatch_queue_t parallelJobsQueue = dispatch_queue_create("ParallelJobs", 0);

        for (int i = 0; i < m_numberOfJobs - 1; ++i) {
            dispatch_async(parallelJobsQueue, ^{(*m_threadFunction)(parameters);});
            parameters += m_sizeOfParameter;
        }

        // The work for the main thread. Wait until all jobs are done.
        dispatch_sync(parallelJobsQueue, ^{(*m_threadFunction)(parameters);});
    }

private:
    ThreadFunction m_threadFunction;
    size_t m_sizeOfParameter;
    int m_numberOfJobs;
};

} // namespace WTF

#endif // ENABLE(THREADING_LIBDISPATCH)

#endif // ParallelJobsLibdispatch_h
Commit	Line	Data
14957cd0 A	1	/*
	2	* Copyright (C) 2011 University of Szeged
	3	* Copyright (C) 2011 Gabor Loki <loki@webkit.org>
	4	* All rights reserved.
	5	*
	6	* Redistribution and use in source and binary forms, with or without
	7	* modification, are permitted provided that the following conditions
	8	* are met:
	9	* 1. Redistributions of source code must retain the above copyright
	10	* notice, this list of conditions and the following disclaimer.
	11	* 2. Redistributions in binary form must reproduce the above copyright
	12	* notice, this list of conditions and the following disclaimer in the
	13	* documentation and/or other materials provided with the distribution.
	14	*
	15	* THIS SOFTWARE IS PROVIDED BY UNIVERSITY OF SZEGED ``AS IS'' AND ANY
	16	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	17	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	18	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL UNIVERSITY OF SZEGED OR
	19	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	20	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	21	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	22	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
	23	* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	24	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	25	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	26	*/
	27
	28	#ifndef ParallelJobsLibdispatch_h
	29	#define ParallelJobsLibdispatch_h
	30
	31	#if ENABLE(THREADING_LIBDISPATCH)
	32
	33	#include <dispatch/dispatch.h>
	34
	35	namespace WTF {
	36
	37	static const int maxParallelThreads = 2;
	38
	39	class ParallelEnvironment {
	40	WTF_MAKE_FAST_ALLOCATED;
	41	public:
	42	typedef void (ThreadFunction)(void);
	43
	44	ParallelEnvironment(ThreadFunction threadFunction, size_t sizeOfParameter, int requestedJobNumber) :
	45	m_threadFunction(threadFunction),
	46	m_sizeOfParameter(sizeOfParameter)
	47	{
	48	if (!requestedJobNumber \|\| requestedJobNumber > maxParallelThreads)
	49	requestedJobNumber = maxParallelThreads;
	50
	51	ASSERT(requestedJobNumber > 0);
	52
	53	m_numberOfJobs = requestedJobNumber;
	54	}
	55
	56	int numberOfJobs()
	57	{
	58	return m_numberOfJobs;
	59	}
	60
	61	void execute(unsigned char* parameters)
	62	{
	63	// libdispatch is NOT supported inside a template
	64	dispatch_queue_t parallelJobsQueue = dispatch_queue_create("ParallelJobs", 0);
65
66	for (int i = 0; i < m_numberOfJobs - 1; ++i) {
67	dispatch_async(parallelJobsQueue, ^{(*m_threadFunction)(parameters);});
68	parameters += m_sizeOfParameter;
69	}
70
71	// The work for the main thread. Wait until all jobs are done.
72	dispatch_sync(parallelJobsQueue, ^{(*m_threadFunction)(parameters);});
73	}
74
75	private:
76	ThreadFunction m_threadFunction;
77	size_t m_sizeOfParameter;
78	int m_numberOfJobs;
79	};
80
81	} // namespace WTF
82
83	#endif // ENABLE(THREADING_LIBDISPATCH)
84
85	#endif // ParallelJobsLibdispatch_h