[tracing] Switch to new heap dump format.

base/trace_event/malloc_dump_provider.cc

 // 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 "base/trace_event/malloc_dump_provider.h"
 
 #include <stddef.h>
 
 #include "base/allocator/allocator_extension.h"
 #include "base/allocator/allocator_shim.h"
 #include "base/allocator/features.h"
 #include "base/debug/profiler.h"
 #include "base/trace_event/heap_profiler_allocation_context.h"
 #include "base/trace_event/heap_profiler_allocation_context_tracker.h"
 #include "base/trace_event/heap_profiler_allocation_register.h"
-#include "base/trace_event/heap_profiler_heap_dump_writer.h"
+#include "base/trace_event/heap_profiler_event_writer.h"
 #include "base/trace_event/process_memory_dump.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "build/build_config.h"
 
 #if defined(OS_MACOSX)
 #include <malloc/malloc.h>
 #else
 #include <malloc.h>
 #endif
 #if defined(OS_WIN)
@@ skipping 253 matching lines @@
                           MemoryAllocatorDump::kUnitsBytes,
                           resident_size - allocated_objects_size);
   }
 
   // Heap profiler dumps.
   if (!heap_profiler_enabled_)
     return true;
 
   // The dumps of the heap profiler should be created only when heap profiling
   // was enabled (--enable-heap-profiling) AND a DETAILED dump is requested.
   // However, when enabled, the overhead of the heap profiler should be always

[ssid, 2017/03/16 02:09:20]

I think this comment should be moved to process_memory_dump.cc

   // reported to avoid oscillations of the malloc total in LIGHT dumps.
 
   tid_dumping_heap_ = PlatformThread::CurrentId();
   // At this point the Insert/RemoveAllocation hooks will ignore this thread.
   // Enclosing all the temporariy data structures in a scope, so that the heap
   // profiler does not see unabalanced malloc/free calls from these containers.
   {
-    TraceEventMemoryOverhead overhead;
-    hash_map<AllocationContext, AllocationMetrics> metrics_by_context;
-    {
-      AutoLock lock(allocation_register_lock_);
-      if (allocation_register_) {
-        if (args.level_of_detail == MemoryDumpLevelOfDetail::DETAILED) {
-          for (const auto& alloc_size : *allocation_register_) {
-            AllocationMetrics& metrics = metrics_by_context[alloc_size.context];
-            metrics.size += alloc_size.size;
-            metrics.count++;
-          }
-        }
-        allocation_register_->EstimateTraceMemoryOverhead(&overhead);
-      }
-    }  // lock(allocation_register_lock_)
-    pmd->DumpHeapUsage(metrics_by_context, overhead, "malloc");
+    AutoLock lock(allocation_register_lock_);
+    if (allocation_register_) {
+      pmd->DumpHeapUsage(*allocation_register_, "malloc");
+    }
   }
   tid_dumping_heap_ = kInvalidThreadId;
 
   return true;
 }
 
 void MallocDumpProvider::OnHeapProfilingEnabled(bool enabled) {
 #if BUILDFLAG(USE_EXPERIMENTAL_ALLOCATOR_SHIM)
   if (enabled) {
     {
@@ skipping 45 matching lines @@
       tid_dumping_heap_ == PlatformThread::CurrentId())
     return;
   AutoLock lock(allocation_register_lock_);
   if (!allocation_register_)
     return;
   allocation_register_->Remove(address);
 }
 
 }  // namespace trace_event
 }  // namespace base