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// Copyright 2020 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/heap/local-heap.h"
#include <memory>
#include "src/base/platform/mutex.h"
#include "src/handles/local-handles.h"
#include "src/heap/heap-inl.h"
#include "src/heap/safepoint.h"
namespace v8 {
namespace internal {
LocalHeap::LocalHeap(Heap* heap,
std::unique_ptr<PersistentHandles> persistent_handles)
: heap_(heap),
state_(ThreadState::Running),
safepoint_requested_(false),
allocation_failed_(false),
prev_(nullptr),
next_(nullptr),
handles_(new LocalHandles),
persistent_handles_(std::move(persistent_handles)),
old_space_allocator_(this, heap->old_space()) {
heap_->safepoint()->AddLocalHeap(this);
if (persistent_handles_) {
persistent_handles_->Attach(this);
}
}
LocalHeap::~LocalHeap() {
// Give up LAB before parking thread
old_space_allocator_.FreeLinearAllocationArea();
// Park thread since removing the local heap could block.
EnsureParkedBeforeDestruction();
heap_->safepoint()->RemoveLocalHeap(this);
}
Handle<Object> LocalHeap::NewPersistentHandle(Address value) {
if (!persistent_handles_) {
persistent_handles_.reset(
heap_->isolate()->NewPersistentHandles().release());
}
return persistent_handles_->NewHandle(value);
}
std::unique_ptr<PersistentHandles> LocalHeap::DetachPersistentHandles() {
if (persistent_handles_) persistent_handles_->Detach();
return std::move(persistent_handles_);
}
bool LocalHeap::IsParked() {
base::MutexGuard guard(&state_mutex_);
return state_ == ThreadState::Parked;
}
void LocalHeap::Park() {
base::MutexGuard guard(&state_mutex_);
CHECK(state_ == ThreadState::Running);
state_ = ThreadState::Parked;
state_change_.NotifyAll();
}
void LocalHeap::Unpark() {
base::MutexGuard guard(&state_mutex_);
CHECK(state_ == ThreadState::Parked);
state_ = ThreadState::Running;
}
void LocalHeap::EnsureParkedBeforeDestruction() {
base::MutexGuard guard(&state_mutex_);
state_ = ThreadState::Parked;
state_change_.NotifyAll();
}
void LocalHeap::RequestSafepoint() {
safepoint_requested_.store(true, std::memory_order_relaxed);
}
bool LocalHeap::IsSafepointRequested() {
return safepoint_requested_.load(std::memory_order_relaxed);
}
void LocalHeap::Safepoint() {
if (IsSafepointRequested()) {
ClearSafepointRequested();
EnterSafepoint();
}
}
void LocalHeap::ClearSafepointRequested() {
safepoint_requested_.store(false, std::memory_order_relaxed);
}
void LocalHeap::EnterSafepoint() { heap_->safepoint()->EnterFromThread(this); }
void LocalHeap::FreeLinearAllocationArea() {
old_space_allocator_.FreeLinearAllocationArea();
}
void LocalHeap::MakeLinearAllocationAreaIterable() {
old_space_allocator_.MakeLinearAllocationAreaIterable();
}
void LocalHeap::MarkLinearAllocationAreaBlack() {
old_space_allocator_.MarkLinearAllocationAreaBlack();
}
void LocalHeap::UnmarkLinearAllocationArea() {
old_space_allocator_.UnmarkLinearAllocationArea();
}
} // namespace internal
} // namespace v8
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