v8/src/sweeper-thread.cc
2014-06-05 12:14:47 +00:00

87 lines
2.2 KiB
C++

// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/sweeper-thread.h"
#include "src/v8.h"
#include "src/isolate.h"
#include "src/v8threads.h"
namespace v8 {
namespace internal {
static const int kSweeperThreadStackSize = 64 * KB;
SweeperThread::SweeperThread(Isolate* isolate)
: Thread(Thread::Options("v8:SweeperThread", kSweeperThreadStackSize)),
isolate_(isolate),
heap_(isolate->heap()),
collector_(heap_->mark_compact_collector()),
start_sweeping_semaphore_(0),
end_sweeping_semaphore_(0),
stop_semaphore_(0) {
ASSERT(!FLAG_job_based_sweeping);
base::NoBarrier_Store(&stop_thread_, static_cast<base::AtomicWord>(false));
}
void SweeperThread::Run() {
Isolate::SetIsolateThreadLocals(isolate_, NULL);
DisallowHeapAllocation no_allocation;
DisallowHandleAllocation no_handles;
DisallowHandleDereference no_deref;
while (true) {
start_sweeping_semaphore_.Wait();
if (base::Acquire_Load(&stop_thread_)) {
stop_semaphore_.Signal();
return;
}
collector_->SweepInParallel(heap_->old_data_space());
collector_->SweepInParallel(heap_->old_pointer_space());
end_sweeping_semaphore_.Signal();
}
}
void SweeperThread::Stop() {
base::Release_Store(&stop_thread_, static_cast<base::AtomicWord>(true));
start_sweeping_semaphore_.Signal();
stop_semaphore_.Wait();
Join();
}
void SweeperThread::StartSweeping() {
start_sweeping_semaphore_.Signal();
}
void SweeperThread::WaitForSweeperThread() {
end_sweeping_semaphore_.Wait();
}
bool SweeperThread::SweepingCompleted() {
bool value = end_sweeping_semaphore_.WaitFor(TimeDelta::FromSeconds(0));
if (value) {
end_sweeping_semaphore_.Signal();
}
return value;
}
int SweeperThread::NumberOfThreads(int max_available) {
if (!FLAG_concurrent_sweeping && !FLAG_parallel_sweeping) return 0;
if (FLAG_sweeper_threads > 0) return FLAG_sweeper_threads;
if (FLAG_concurrent_sweeping) return max_available - 1;
ASSERT(FLAG_parallel_sweeping);
return max_available;
}
} } // namespace v8::internal