src/marking-thread.cc

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#include "marking-thread.h"

#include "v8.h"

#include "isolate.h"
#include "v8threads.h"

namespace v8 {
namespace internal {

MarkingThread::MarkingThread(Isolate* isolate)
     : Thread("MarkingThread"),
       isolate_(isolate),
       heap_(isolate->heap()),
       start_marking_semaphore_(OS::CreateSemaphore(0)),
       end_marking_semaphore_(OS::CreateSemaphore(0)),
       stop_semaphore_(OS::CreateSemaphore(0)) {
  NoBarrier_Store(&stop_thread_, static_cast<AtomicWord>(false));
  id_ = NoBarrier_AtomicIncrement(&id_counter_, 1);
}


Atomic32 MarkingThread::id_counter_ = -1;


void MarkingThread::Run() {
  Isolate::SetIsolateThreadLocals(isolate_, NULL);
  DisallowHeapAllocation no_allocation;
  DisallowHandleAllocation no_handles;
  DisallowHandleDereference no_deref;

  while (true) {
    start_marking_semaphore_->Wait();

    if (Acquire_Load(&stop_thread_)) {
      stop_semaphore_->Signal();
      return;
    }

    end_marking_semaphore_->Signal();
  }
}


void MarkingThread::Stop() {
  Release_Store(&stop_thread_, static_cast<AtomicWord>(true));
  start_marking_semaphore_->Signal();
  stop_semaphore_->Wait();
}


void MarkingThread::StartMarking() {
  start_marking_semaphore_->Signal();
}


void MarkingThread::WaitForMarkingThread() {
  end_marking_semaphore_->Wait();
}

} }  // namespace v8::internal