third_party/WebKit/Source/platform/TaskSynchronizer.cpp

/*
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 *     its contributors may be used to endorse or promote products derived
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#include "platform/TaskSynchronizer.h"

#include "platform/heap/SafePoint.h"
#include "platform/heap/ThreadState.h"

namespace blink {

TaskSynchronizer::TaskSynchronizer()
    : m_taskCompleted(false)
{
}

void TaskSynchronizer::waitForTaskCompletion()
{
    if (ThreadState::current()) {
        // Prevent the deadlock between park request by other threads and blocking
        // by m_synchronousCondition.
        SafePointScope scope(BlinkGC::HeapPointersOnStack);
        waitForTaskCompletionInternal();
    } else {
        // If this thread is already detached, we no longer need to enter a safe point scope.
        waitForTaskCompletionInternal();
    }
}

void TaskSynchronizer::waitForTaskCompletionInternal()
{
    m_synchronousMutex.lock();
    while (!m_taskCompleted)
        m_synchronousCondition.wait(m_synchronousMutex);
    m_synchronousMutex.unlock();
}

void TaskSynchronizer::taskCompleted()
{
    m_synchronousMutex.lock();
    m_taskCompleted = true;
    m_synchronousCondition.signal();
    m_synchronousMutex.unlock();
}

} // namespace blink