Make TimelineEventBlocks reclaimable

runtime/vm/timeline.h

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_TIMELINE_H_
 #define VM_TIMELINE_H_
 
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
 
@@ skipping 27 matching lines @@
   // Shutdown timeline system. Not thread safe.
   static void Shutdown();
 
   // Access the global recorder. Not thread safe.
   static TimelineEventRecorder* recorder();
 
   static bool EnableStreamByDefault(const char* stream_name);
 
   static TimelineStream* GetVMStream();
 
+  // Reclaim all |TimelineEventBlock|s that are owned by the current isolate.
+  static void ReclaimIsolateBlocks();
+
+  // Reclaim all |TimelineEventBlocks|s that are owned by all isolates and
+  // the global block owned by the VM.
+  static void ReclaimAllBlocks();
+
 #define ISOLATE_TIMELINE_STREAM_FLAGS(name, not_used)                          \
   static const bool* Stream##name##EnabledFlag() {                             \
     return &stream_##name##_enabled_;                                          \
   }                                                                            \
   static void SetStream##name##Enabled(bool enabled) {                         \
     stream_##name##_enabled_ = enabled;                                        \
   }
   ISOLATE_TIMELINE_STREAM_LIST(ISOLATE_TIMELINE_STREAM_FLAGS)
 #undef ISOLATE_TIMELINE_STREAM_FLAGS
 
  private:
+  static void ReclaimBlocksForIsolate(Isolate* isolate);
+
   static TimelineEventRecorder* recorder_;
   static TimelineStream* vm_stream_;
 
 #define ISOLATE_TIMELINE_STREAM_DECLARE_FLAG(name, not_used)                   \
   static bool stream_##name##_enabled_;
   ISOLATE_TIMELINE_STREAM_LIST(ISOLATE_TIMELINE_STREAM_DECLARE_FLAG)
 #undef ISOLATE_TIMELINE_STREAM_DECLARE_FLAG
 
   friend class TimelineRecorderOverride;
+  friend class ReclaimBlocksIsolateVisitor;
 };
 
 
 // You should get a |TimelineEvent| from a |TimelineStream|.
 class TimelineEvent {
  public:
   // Keep in sync with StateBits below.
   enum EventType {
     kNone,
     kDuration,
@@ skipping 376 matching lines @@
 
 class IsolateTimelineEventFilter : public TimelineEventFilter {
  public:
   explicit IsolateTimelineEventFilter(Isolate* isolate);
 
   bool IncludeBlock(TimelineEventBlock* block) {
     if (block == NULL) {
       return false;
     }
     // Not empty, not open, and isolate match.
-    return !block->IsEmpty() &&
+    return !block->IsEmpty() && !block->open() &&

[turnidge, 2015/09/24 17:05:52]

Consider in_use instead of open?

[Cutch, 2015/09/24 18:14:16]

Done.

            (block->isolate() == isolate_);
   }
 
  private:
   Isolate* isolate_;
 };
 
 
 // Recorder of |TimelineEvent|s.
 class TimelineEventRecorder {
@@ skipping 18 matching lines @@
   virtual TimelineEventBlock* GetNewBlockLocked(Isolate* isolate) = 0;
 
   // Utility method(s).
   void PrintJSONMeta(JSONArray* array) const;
   TimelineEvent* ThreadBlockStartEvent();
   TimelineEvent* GlobalBlockStartEvent();
 
   Mutex lock_;
   // Only accessed under |lock_|.
   TimelineEventBlock* global_block_;
-  void FinishGlobalBlock();
+  void ReclaimGlobalBlock();
 
   uintptr_t async_id_;
 
   friend class ThreadRegistry;
   friend class TimelineEvent;
   friend class TimelineEventBlockIterator;
   friend class TimelineStream;
   friend class TimelineTestHelper;
   friend class Timeline;
   friend class Isolate;
@@ skipping 98 matching lines @@
   TimelineEventBlock* Next();
 
  private:
   TimelineEventBlock* current_;
   TimelineEventRecorder* recorder_;
 };
 
 }  // namespace dart
 
 #endif  // VM_TIMELINE_H_