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// Copyright 2016 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.
#ifndef V8_ZONE_ACCOUNTING_ALLOCATOR_H_
#define V8_ZONE_ACCOUNTING_ALLOCATOR_H_
#include <atomic>
#include <memory>
#include "include/v8-platform.h"
#include "src/base/macros.h"
#include "src/logging/tracing-flags.h"
namespace v8 {
namespace base {
class BoundedPageAllocator;
} // namespace base
namespace internal {
class Segment;
class VirtualMemory;
class Zone;
class V8_EXPORT_PRIVATE AccountingAllocator {
public:
AccountingAllocator();
AccountingAllocator(const AccountingAllocator&) = delete;
AccountingAllocator& operator=(const AccountingAllocator&) = delete;
virtual ~AccountingAllocator();
// Allocates a new segment. Returns nullptr on failed allocation.
Segment* AllocateSegment(size_t bytes, bool supports_compression);
// Return unneeded segments to either insert them into the pool or release
// them if the pool is already full or memory pressure is high.
void ReturnSegment(Segment* memory, bool supports_compression);
size_t GetCurrentMemoryUsage() const {
return current_memory_usage_.load(std::memory_order_relaxed);
}
size_t GetMaxMemoryUsage() const {
return max_memory_usage_.load(std::memory_order_relaxed);
}
void TraceZoneCreation(const Zone* zone) {
if (V8_LIKELY(!TracingFlags::is_zone_stats_enabled())) return;
TraceZoneCreationImpl(zone);
}
void TraceZoneDestruction(const Zone* zone) {
if (V8_LIKELY(!TracingFlags::is_zone_stats_enabled())) return;
TraceZoneDestructionImpl(zone);
}
void TraceAllocateSegment(Segment* segment) {
if (V8_LIKELY(!TracingFlags::is_zone_stats_enabled())) return;
TraceAllocateSegmentImpl(segment);
}
protected:
virtual void TraceZoneCreationImpl(const Zone* zone) {}
virtual void TraceZoneDestructionImpl(const Zone* zone) {}
virtual void TraceAllocateSegmentImpl(Segment* segment) {}
private:
std::atomic<size_t> current_memory_usage_{0};
std::atomic<size_t> max_memory_usage_{0};
std::unique_ptr<VirtualMemory> reserved_area_;
std::unique_ptr<base::BoundedPageAllocator> bounded_page_allocator_;
ZoneBackingAllocator::MallocFn zone_backing_malloc_ = nullptr;
ZoneBackingAllocator::FreeFn zone_backing_free_ = nullptr;
};
} // namespace internal
} // namespace v8
#endif // V8_ZONE_ACCOUNTING_ALLOCATOR_H_
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