Enable sharding of AllocationRegister on desktop.

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 <unordered_map>
 
 #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/sharded_allocation_register.h"
 #include "base/trace_event/trace_event_memory_overhead.h"
 #include "platform/heap/Handle.h"
 #include "platform/instrumentation/tracing/web_memory_allocator_dump.h"
 #include "platform/wtf/StdLibExtras.h"
 #include "platform/wtf/Threading.h"
 #include "public/platform/Platform.h"
 
 namespace blink {
 namespace {
 
@@ skipping 36 matching lines @@
   using base::trace_event::MemoryDumpLevelOfDetail;
   MemoryDumpLevelOfDetail level_of_detail = args.level_of_detail;
   // In the case of a detailed dump perform a mark-only GC pass to collect
   // more detailed stats.
   if (level_of_detail == MemoryDumpLevelOfDetail::DETAILED)
     ThreadState::Current()->CollectGarbage(BlinkGC::kNoHeapPointersOnStack,
                                            BlinkGC::kTakeSnapshot,
                                            BlinkGC::kForcedGC);
   DumpMemoryTotals(memory_dump);
 
-  if (is_heap_profiling_enabled_) {
+  if (allocation_register_->IsEnabled()) {
     // Overhead should always be reported, regardless of light vs. heavy.
     base::trace_event::TraceEventMemoryOverhead overhead;
     std::unordered_map<base::trace_event::AllocationContext,
                        base::trace_event::AllocationMetrics>
         metrics_by_context;
-    {
-      MutexLocker locker(allocation_register_mutex_);
-      if (level_of_detail == MemoryDumpLevelOfDetail::DETAILED) {
-        for (const auto& alloc_size : *allocation_register_) {
-          base::trace_event::AllocationMetrics& metrics =
-              metrics_by_context[alloc_size.context];
-          metrics.size += alloc_size.size;
-          metrics.count++;
-        }
-      }
-      allocation_register_->EstimateTraceMemoryOverhead(&overhead);
+    if (level_of_detail == MemoryDumpLevelOfDetail::DETAILED) {
+      allocation_register_->UpdateAndReturnsMetrics(metrics_by_context);
     }
+    allocation_register_->EstimateTraceMemoryOverhead(&overhead);
     memory_dump->DumpHeapUsage(metrics_by_context, overhead, "blink_gc");
   }
 
   // Merge all dumps collected by ThreadHeap::collectGarbage.
   if (level_of_detail == MemoryDumpLevelOfDetail::DETAILED)
     memory_dump->TakeAllDumpsFrom(current_process_memory_dump_.get());
   return true;
 }
 
 void BlinkGCMemoryDumpProvider::OnHeapProfilingEnabled(bool enabled) {
   if (enabled) {
-    {
-      MutexLocker locker(allocation_register_mutex_);
-      if (!allocation_register_)
-        allocation_register_.reset(new base::trace_event::AllocationRegister());
-    }
+    if (!allocation_register_->IsInitialized())
+      allocation_register_->Initialize();
     HeapAllocHooks::SetAllocationHook(ReportAllocation);
     HeapAllocHooks::SetFreeHook(ReportFree);
   } else {
     HeapAllocHooks::SetAllocationHook(nullptr);
     HeapAllocHooks::SetFreeHook(nullptr);
   }
-  is_heap_profiling_enabled_ = enabled;
+  allocation_register_->SetEnabled(enabled);
 }
 
 base::trace_event::MemoryAllocatorDump*
 BlinkGCMemoryDumpProvider::CreateMemoryAllocatorDumpForCurrentGC(
     const String& absolute_name) {
   // TODO(bashi): Change type name of |absoluteName|.
   return current_process_memory_dump_->CreateAllocatorDump(
       absolute_name.Utf8().data());
 }
 
 void BlinkGCMemoryDumpProvider::ClearProcessDumpForCurrentGC() {
   current_process_memory_dump_->Clear();
 }
 
 BlinkGCMemoryDumpProvider::BlinkGCMemoryDumpProvider()
-    : current_process_memory_dump_(new base::trace_event::ProcessMemoryDump(
+    : allocation_register_(new base::trace_event::ShardedAllocationRegister),
+      current_process_memory_dump_(new base::trace_event::ProcessMemoryDump(
           nullptr,
-          {base::trace_event::MemoryDumpLevelOfDetail::DETAILED})),
-      is_heap_profiling_enabled_(false) {}
+          {base::trace_event::MemoryDumpLevelOfDetail::DETAILED})) {}
 
 void BlinkGCMemoryDumpProvider::insert(Address address,
                                        size_t size,
                                        const char* type_name) {
   base::trace_event::AllocationContext context;
   if (!base::trace_event::AllocationContextTracker::
            GetInstanceForCurrentThread()
                ->GetContextSnapshot(&context))
     return;
   context.type_name = type_name;
-  MutexLocker locker(allocation_register_mutex_);
-  if (allocation_register_)
-    allocation_register_->Insert(address, size, context);
+  if (!allocation_register_->IsEnabled())
+    return;
+  allocation_register_->Insert(address, size, context);
 }
 
 void BlinkGCMemoryDumpProvider::Remove(Address address) {
-  MutexLocker locker(allocation_register_mutex_);
-  if (allocation_register_)
-    allocation_register_->Remove(address);
+  if (!allocation_register_->IsEnabled())
+    return;
+  allocation_register_->Remove(address);
 }
 
 }  // namespace blink