| /* |
| * 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. |
| */ |
| |
| #include "config.h" |
| |
| #if ENABLE(THREADING_GENERIC) |
| |
| #include "ParallelJobs.h" |
| #include <wtf/NumberOfCores.h> |
| |
| namespace WTF { |
| |
| Vector< RefPtr<ParallelEnvironment::ThreadPrivate> >* ParallelEnvironment::s_threadPool = 0; |
| |
| ParallelEnvironment::ParallelEnvironment(ThreadFunction threadFunction, size_t sizeOfParameter, int requestedJobNumber) : |
| m_threadFunction(threadFunction), |
| m_sizeOfParameter(sizeOfParameter) |
| { |
| ASSERT_ARG(requestedJobNumber, requestedJobNumber >= 1); |
| |
| int maxNumberOfCores = numberOfProcessorCores(); |
| |
| if (!requestedJobNumber || requestedJobNumber > maxNumberOfCores) |
| requestedJobNumber = static_cast<unsigned>(maxNumberOfCores); |
| |
| if (!s_threadPool) |
| s_threadPool = new Vector< RefPtr<ThreadPrivate> >(); |
| |
| // The main thread should be also a worker. |
| int maxNumberOfNewThreads = requestedJobNumber - 1; |
| |
| for (int i = 0; i < maxNumberOfCores && m_threads.size() < static_cast<unsigned>(maxNumberOfNewThreads); ++i) { |
| if (s_threadPool->size() < static_cast<unsigned>(i) + 1U) |
| s_threadPool->append(ThreadPrivate::create()); |
| |
| if ((*s_threadPool)[i]->tryLockFor(this)) |
| m_threads.append((*s_threadPool)[i]); |
| } |
| |
| m_numberOfJobs = m_threads.size() + 1; |
| } |
| |
| void ParallelEnvironment::execute(void* parameters) |
| { |
| unsigned char* currentParameter = static_cast<unsigned char*>(parameters); |
| size_t i; |
| for (i = 0; i < m_threads.size(); ++i) { |
| m_threads[i]->execute(m_threadFunction, currentParameter); |
| currentParameter += m_sizeOfParameter; |
| } |
| |
| // The work for the main thread. |
| (*m_threadFunction)(currentParameter); |
| |
| // Wait until all jobs are done. |
| for (i = 0; i < m_threads.size(); ++i) |
| m_threads[i]->waitForFinish(); |
| } |
| |
| bool ParallelEnvironment::ThreadPrivate::tryLockFor(ParallelEnvironment* parent) |
| { |
| bool locked = m_mutex.tryLock(); |
| |
| if (!locked) |
| return false; |
| |
| if (m_parent) { |
| m_mutex.unlock(); |
| return false; |
| } |
| |
| if (!m_threadID) |
| m_threadID = createThread(&ParallelEnvironment::ThreadPrivate::workerThread, this, "Parallel worker"); |
| |
| if (m_threadID) |
| m_parent = parent; |
| |
| m_mutex.unlock(); |
| return m_threadID; |
| } |
| |
| void ParallelEnvironment::ThreadPrivate::execute(ThreadFunction threadFunction, void* parameters) |
| { |
| MutexLocker lock(m_mutex); |
| |
| m_threadFunction = threadFunction; |
| m_parameters = parameters; |
| m_running = true; |
| m_threadCondition.signal(); |
| } |
| |
| void ParallelEnvironment::ThreadPrivate::waitForFinish() |
| { |
| MutexLocker lock(m_mutex); |
| |
| while (m_running) |
| m_threadCondition.wait(m_mutex); |
| } |
| |
| void ParallelEnvironment::ThreadPrivate::workerThread(void* threadData) |
| { |
| ThreadPrivate* sharedThread = reinterpret_cast<ThreadPrivate*>(threadData); |
| MutexLocker lock(sharedThread->m_mutex); |
| |
| while (sharedThread->m_threadID) { |
| if (sharedThread->m_running) { |
| (*sharedThread->m_threadFunction)(sharedThread->m_parameters); |
| sharedThread->m_running = false; |
| sharedThread->m_parent = 0; |
| sharedThread->m_threadCondition.signal(); |
| } |
| |
| sharedThread->m_threadCondition.wait(sharedThread->m_mutex); |
| } |
| } |
| |
| } // namespace WTF |
| #endif // ENABLE(THREADING_GENERIC) |