third_party/WebKit/Source/platform/heap/BlinkGCMemoryDumpProvider.cpp

// Copyright 2015 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 "platform/heap/BlinkGCMemoryDumpProvider.h"

#include "base/trace_event/heap_profiler_allocation_context_tracker.h"
#include "base/trace_event/heap_profiler_allocation_register.h"
#include "base/trace_event/memory_allocator_dump.h"
#include "base/trace_event/process_memory_dump.h"
#include "base/trace_event/trace_event_memory_overhead.h"
#include "platform/heap/Handle.h"
#include "platform/web_process_memory_dump_impl.h"
#include "public/platform/Platform.h"
#include "public/platform/WebMemoryAllocatorDump.h"
#include "wtf/StdLibExtras.h"
#include "wtf/Threading.h"

namespace blink {
namespace {

void dumpMemoryTotals(base::trace_event::ProcessMemoryDump* memoryDump)
{
    base::trace_event::MemoryAllocatorDump* allocatorDump = memoryDump->CreateAllocatorDump("blink_gc");
    allocatorDump->AddScalar("size", "bytes", ProcessHeap::totalAllocatedSpace());

    base::trace_event::MemoryAllocatorDump* objectsDump = memoryDump->CreateAllocatorDump("blink_gc/allocated_objects");

    // ThreadHeap::markedObjectSize() can be underestimated if we're still in the
    // process of lazy sweeping.
    objectsDump->AddScalar("size", "bytes", ProcessHeap::totalAllocatedObjectSize() + ProcessHeap::totalMarkedObjectSize());
}

void reportAllocation(Address address, size_t size, const char* typeName)
{
    BlinkGCMemoryDumpProvider::instance()->insert(address, size, typeName);
}

void reportFree(Address address)
{
    BlinkGCMemoryDumpProvider::instance()->remove(address);
}

} // namespace

BlinkGCMemoryDumpProvider* BlinkGCMemoryDumpProvider::instance()
{
    DEFINE_STATIC_LOCAL(BlinkGCMemoryDumpProvider, instance, ());
    return &instance;
}

BlinkGCMemoryDumpProvider::~BlinkGCMemoryDumpProvider()
{
}

bool BlinkGCMemoryDumpProvider::OnMemoryDump(const base::trace_event::MemoryDumpArgs& args, base::trace_event::ProcessMemoryDump* memoryDump)
{
    using base::trace_event::MemoryDumpLevelOfDetail;
    MemoryDumpLevelOfDetail levelOfDetail = args.level_of_detail;
    // In the case of a detailed dump perform a mark-only GC pass to collect
    // more detailed stats.
    if (levelOfDetail == MemoryDumpLevelOfDetail::DETAILED)
        ThreadHeap::collectGarbage(BlinkGC::NoHeapPointersOnStack, BlinkGC::TakeSnapshot, BlinkGC::ForcedGC);
    dumpMemoryTotals(memoryDump);

    if (m_isHeapProfilingEnabled) {
        // Overhead should always be reported, regardless of light vs. heavy.
        base::trace_event::TraceEventMemoryOverhead overhead;
        base::hash_map<base::trace_event::AllocationContext, base::trace_event::AllocationMetrics> metricsByContext;
        {
            MutexLocker locker(m_allocationRegisterMutex);
            if (levelOfDetail == MemoryDumpLevelOfDetail::DETAILED) {
                for (const auto& allocSize : *m_allocationRegister) {
                    base::trace_event::AllocationMetrics& metrics = metricsByContext[allocSize.context];
                    metrics.size += allocSize.size;
                    metrics.count++;
                }
            }
            m_allocationRegister->EstimateTraceMemoryOverhead(&overhead);
        }
        memoryDump->DumpHeapUsage(metricsByContext, overhead, "blink_gc");
    }

    // Merge all dumps collected by ThreadHeap::collectGarbage.
    if (levelOfDetail == MemoryDumpLevelOfDetail::DETAILED)
        memoryDump->TakeAllDumpsFrom(m_currentProcessMemoryDump.get());
    return true;
}

void BlinkGCMemoryDumpProvider::OnHeapProfilingEnabled(bool enabled)
{
    if (enabled) {
        {
            MutexLocker locker(m_allocationRegisterMutex);
            if (!m_allocationRegister)
                m_allocationRegister.reset(new base::trace_event::AllocationRegister());
        }
        HeapAllocHooks::setAllocationHook(reportAllocation);
        HeapAllocHooks::setFreeHook(reportFree);
    } else {
        HeapAllocHooks::setAllocationHook(nullptr);
        HeapAllocHooks::setFreeHook(nullptr);
    }
    m_isHeapProfilingEnabled = enabled;
}

base::trace_event::MemoryAllocatorDump* BlinkGCMemoryDumpProvider::createMemoryAllocatorDumpForCurrentGC(const String& absoluteName)
{
    // TODO(bashi): Change type name of |absoluteName|.
    return m_currentProcessMemoryDump->CreateAllocatorDump(absoluteName.utf8().data());
}

void BlinkGCMemoryDumpProvider::clearProcessDumpForCurrentGC()
{
    m_currentProcessMemoryDump->Clear();
}

BlinkGCMemoryDumpProvider::BlinkGCMemoryDumpProvider()
    : m_currentProcessMemoryDump(new base::trace_event::ProcessMemoryDump(nullptr))
    , m_isHeapProfilingEnabled(false)
{
}

void BlinkGCMemoryDumpProvider::insert(Address address, size_t size, const char* typeName)
{
    base::trace_event::AllocationContext context = base::trace_event::AllocationContextTracker::GetInstanceForCurrentThread()->GetContextSnapshot();
    context.type_name = typeName;
    MutexLocker locker(m_allocationRegisterMutex);
    if (m_allocationRegister)
        m_allocationRegister->Insert(address, size, context);
}

void BlinkGCMemoryDumpProvider::remove(Address address)
{
    MutexLocker locker(m_allocationRegisterMutex);
    if (m_allocationRegister)
        m_allocationRegister->Remove(address);
}

} // namespace blink