| // 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 <unordered_map> |
| |
| #include "base/base_export.h" |
| #include "base/macros.h" |
| #include "base/trace_event/heap_profiler_allocation_context.h" |
| |
| namespace base { |
| namespace trace_event { |
| |
| class HeapProfilerSerializationState; |
| 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 std::unordered_map<AllocationContext, AllocationMetrics>& |
| metrics_by_context, |
| const HeapProfilerSerializationState& heap_profiler_serialization_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; |
| size_t count; |
| |
| // References a backtrace in the stack frame deduplicator. -1 means empty |
| // backtrace (the root of the tree). |
| int stack_frame_id; |
| |
| // References a type name in the type name deduplicator. -1 indicates that |
| // the size is the cumulative size for all types (the root of the tree). |
| int type_id; |
| }; |
| |
| // Comparison operator to enable putting |Entry| in a |std::set|. |
| 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 |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, |
| 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 std::unordered_map<AllocationContext, AllocationMetrics>& |
| metrics_by_context); |
| |
| private: |
| // Inserts an |Entry| for |Bucket| into |entries_|. Returns false if the |
| // entry was present before, true if it was not. |
| bool AddEntryForBucket(const Bucket& bucket); |
| |
| // Recursively breaks down a bucket into smaller buckets and adds entries for |
| // the buckets worth dumping to |entries_|. |
| void BreakDown(const Bucket& bucket); |
| |
| // The collection of entries that is filled by |Summarize|. |
| 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_ |