blob: 2592f974bc38bfef3575f79e705ba697a3f51c9b [file] [log] [blame]
// Copyright 2017 The Chromium 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 <memory>
#include <unordered_map>
#include <vector>
#include "base/atomicops.h"
#include "base/base_export.h"
#include "base/macros.h"
#include "base/synchronization/lock.h"
#include "base/trace_event/heap_profiler_allocation_register.h"
namespace base {
namespace trace_event {
class TraceEventMemoryOverhead;
// This container holds allocations, and context for each allocation [in the
// form of a back trace].
// This container is thread-safe.
class BASE_EXPORT ShardedAllocationRegister {
using MetricsMap = std::unordered_map<AllocationContext, AllocationMetrics>;
struct OutputMetrics {
// Total size of allocated objects.
size_t size;
// Total count of allocated objects.
size_t count;
// This class must be enabled before calling Insert() or Remove(). Once the
// class is enabled, it's okay if Insert() or Remove() is called [due to
// races] after the class is disabled.
void SetEnabled();
void SetDisabled();
bool is_enabled() const { return !!base::subtle::Acquire_Load(&enabled_); }
// Inserts allocation details into the container. If the address was present
// already, its details are updated. |address| must not be null.
// Returns true if an insert occurred. Inserts may fail because the table
// is full.
bool Insert(const void* address,
size_t size,
const AllocationContext& context);
// Removes the address from the container if it is present. It is ok to call
// this with a null pointer.
void Remove(const void* address);
// Finds allocation for the address and fills |out_allocation|.
bool Get(const void* address,
AllocationRegister::Allocation* out_allocation) const;
// Estimates memory overhead including |sizeof(AllocationRegister)|.
void EstimateTraceMemoryOverhead(TraceEventMemoryOverhead* overhead) const;
// Updates |map| with all allocated objects and their statistics.
// Returns aggregate statistics.
OutputMetrics UpdateAndReturnsMetrics(MetricsMap& map) const;
struct RegisterAndLock {
AllocationRegister allocation_register;
Lock lock;
std::unique_ptr<RegisterAndLock[]> allocation_registers_;
// This member needs to be checked on every allocation and deallocation [fast
// path] when heap profiling is enabled. Using a lock here causes significant
// contention.
base::subtle::Atomic32 enabled_;
} // namespace trace_event
} // namespace base