Add configurable limit to allocations in heap profiler.

base/trace_event/heap_profiler_heap_dump_writer.h

 // 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.
 
 #ifndef BASE_TRACE_EVENT_HEAP_PROFILER_HEAP_DUMP_WRITER_H_
 #define BASE_TRACE_EVENT_HEAP_PROFILER_HEAP_DUMP_WRITER_H_
 
 #include <stddef.h>
 
 #include <memory>
 #include <set>
 
 #include "base/base_export.h"
 #include "base/containers/hash_tables.h"
 #include "base/macros.h"
 #include "base/trace_event/heap_profiler_allocation_context.h"
 
 namespace base {
 namespace trace_event {
 
+class MemoryDumpSessionState;
 class StackFrameDeduplicator;
 class TracedValue;
 class TypeNameDeduplicator;
 
 // Aggregates |metrics_by_context|, recursively breaks down the heap, and
 // returns a traced value with an "entries" array that can be dumped in the
 // trace log, following the format described in https://goo.gl/KY7zVE. The
 // number of entries is kept reasonable because long tails are not included.
 BASE_EXPORT std::unique_ptr<TracedValue> ExportHeapDump(
     const hash_map<AllocationContext, AllocationMetrics>& metrics_by_context,
-    StackFrameDeduplicator* stack_frame_deduplicator,
-    TypeNameDeduplicator* type_name_deduplicator);
+    const MemoryDumpSessionState& session_state);
 
 namespace internal {
 
 namespace {
 struct Bucket;
 }
 
 // An entry in the "entries" array as described in https://goo.gl/KY7zVE.
 struct BASE_EXPORT Entry {
   size_t size;
@@ skipping 12 matching lines @@
 BASE_EXPORT bool operator<(Entry lhs, Entry rhs);
 
 // Serializes entries to an "entries" array in a traced value.
 BASE_EXPORT std::unique_ptr<TracedValue> Serialize(const std::set<Entry>& dump);
 
 // Helper class to dump a snapshot of an |AllocationRegister| or other heap
 // bookkeeping structure into a |TracedValue|. This class is intended to be
 // used as a one-shot local instance on the stack.
 class BASE_EXPORT HeapDumpWriter {
  public:
-  // The |StackFrameDeduplicator| and |TypeNameDeduplicator| are not owned. The
-  // heap dump writer assumes exclusive access to them during the lifetime of
-  // the dump writer.
+  // The |stack_frame_deduplicator| and |type_name_deduplicator| are not owned.
+  // The heap dump writer assumes exclusive access to them during the lifetime
+  // of the dump writer. The heap dumps are broken down for allocations bigger
+  // than |breakdown_threshold_bytes|.
   HeapDumpWriter(StackFrameDeduplicator* stack_frame_deduplicator,
-                 TypeNameDeduplicator* type_name_deduplicator);
+                 TypeNameDeduplicator* type_name_deduplicator,
+                 uint32_t breakdown_threshold_bytes);
 
   ~HeapDumpWriter();
 
   // Aggregates allocations to compute the total size of the heap, then breaks
   // down the heap recursively. This produces the values that should be dumped
   // in the "entries" array. The number of entries is kept reasonable because
   // long tails are not included. Use |Serialize| to convert to a traced value.
   const std::set<Entry>& Summarize(
       const hash_map<AllocationContext, AllocationMetrics>& metrics_by_context);
 
@@ skipping 10 matching lines @@
   std::set<Entry> entries_;
 
   // Helper for generating the |stackFrames| dictionary. Not owned, must outlive
   // this heap dump writer instance.
   StackFrameDeduplicator* const stack_frame_deduplicator_;
 
   // Helper for converting type names to IDs. Not owned, must outlive this heap
   // dump writer instance.
   TypeNameDeduplicator* const type_name_deduplicator_;
 
+  // Minimum size of an allocation for which an allocation bucket will be
+  // broken down with children.
+  uint32_t breakdown_threshold_bytes_;
+
   DISALLOW_COPY_AND_ASSIGN(HeapDumpWriter);
 };
 
 }  // namespace internal
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_HEAP_PROFILER_HEAP_DUMP_WRITER_H_