[heap] GCTracer: Record details for incremental marking

src/heap/gc-tracer.h

Index: src/heap/gc-tracer.h
diff --git a/src/heap/gc-tracer.h b/src/heap/gc-tracer.h
index 531bba3cea78090e3cc47c5c48e54f3d0547655a..a11823e984f63ba1f25c3ddcca0c607e81571b50 100644
--- a/src/heap/gc-tracer.h
+++ b/src/heap/gc-tracer.h
@@ -60,12 +60,15 @@ inline BytesAndDuration MakeBytesAndDuration(uint64_t bytes, double duration) {
 
 enum ScavengeSpeedMode { kForAllObjects, kForSurvivedObjects };
 
-#define INCREMENTAL_SCOPES(F)                \
-  F(MC_INCREMENTAL_WRAPPER_PROLOGUE)         \
-  F(MC_INCREMENTAL_WRAPPER_TRACING)          \
-  F(MC_INCREMENTAL_FINALIZE)                 \
-  F(MC_INCREMENTAL_FINALIZE_OBJECT_GROUPING) \
-  F(MC_INCREMENTAL_EXTERNAL_EPILOGUE)        \
+#define INCREMENTAL_SCOPES(F)                                      \
+  /* MC_INCREMENTAL is the top-level incremental marking scope. */ \
+  F(MC_INCREMENTAL)                                                \
+  F(MC_INCREMENTAL_WRAPPER_PROLOGUE)                               \
+  F(MC_INCREMENTAL_WRAPPER_TRACING)                                \
+  F(MC_INCREMENTAL_FINALIZE)                                       \
+  F(MC_INCREMENTAL_FINALIZE_BODY)                                  \
+  F(MC_INCREMENTAL_FINALIZE_OBJECT_GROUPING)                       \
+  F(MC_INCREMENTAL_EXTERNAL_EPILOGUE)                              \
   F(MC_INCREMENTAL_EXTERNAL_PROLOGUE)
 
 #define TRACER_SCOPES(F)                      \
@@ -128,9 +131,30 @@ enum ScavengeSpeedMode { kForAllObjects, kForSurvivedObjects };
 
 // GCTracer collects and prints ONE line after each garbage collector
 // invocation IFF --trace_gc is used.
-// TODO(ernstm): Unit tests.
 class GCTracer {
  public:
+  struct IncrementalMarkingInfos {
+    IncrementalMarkingInfos()
+        : cumulative_duration(0), longest_step(0), steps(0) {}
+
+    void Update(double duration) {
+      steps++;
+      cumulative_duration += duration;
+      if (duration > longest_step) {
+        longest_step = duration;
+      }
+    }
+
+    void ResetCurrentCycle() {
+      longest_step = 0;
+      steps = 0;
+    }
+
+    double cumulative_duration;
+    double longest_step;
+    int steps;
+  };
+
   class Scope {
    public:
     enum ScopeId {
@@ -139,7 +163,7 @@ class GCTracer {
 #undef DEFINE_SCOPE
           NUMBER_OF_SCOPES,
 
-      FIRST_INCREMENTAL_SCOPE = MC_INCREMENTAL_WRAPPER_PROLOGUE,
+      FIRST_INCREMENTAL_SCOPE = MC_INCREMENTAL,
       LAST_INCREMENTAL_SCOPE = MC_INCREMENTAL_EXTERNAL_PROLOGUE,
       NUMBER_OF_INCREMENTAL_SCOPES =
           LAST_INCREMENTAL_SCOPE - FIRST_INCREMENTAL_SCOPE + 1
@@ -168,9 +192,6 @@ class GCTracer {
       START = 3
     };
 
-    // Default constructor leaves the event uninitialized.
-    Event() {}
-
     Event(Type type, const char* gc_reason, const char* collector_reason);
 
     // Returns a string describing the event type.
@@ -213,19 +234,10 @@ class GCTracer {
 
     // Size of new space objects in constructor.
     intptr_t new_space_object_size;
+
     // Size of survived new space objects in destructor.
     intptr_t survived_new_space_object_size;
 
-    // Number of incremental marking steps since creation of tracer.
-    // (value at start of event)
-    int cumulative_incremental_marking_steps;
-
-    // Incremental marking steps since
-    // - last event for SCAVENGER events
-    // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR
-    // events
-    int incremental_marking_steps;
-
     // Bytes marked since creation of tracer (value at start of event).
     intptr_t cumulative_incremental_marking_bytes;
 
@@ -235,16 +247,6 @@ class GCTracer {
     // events
     intptr_t incremental_marking_bytes;
 
-    // Cumulative duration of incremental marking steps since creation of
-    // tracer. (value at start of event)
-    double cumulative_incremental_marking_duration;
-
-    // Duration of incremental marking steps since
-    // - last event for SCAVENGER events
-    // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR
-    // events
-    double incremental_marking_duration;
-
     // Cumulative pure duration of incremental marking steps since creation of
     // tracer. (value at start of event)
     double cumulative_pure_incremental_marking_duration;
@@ -255,37 +257,12 @@ class GCTracer {
     // events
     double pure_incremental_marking_duration;
 
-    // Longest incremental marking step since start of marking (start of event).
-    double longest_incremental_marking_step;
-
-    // Number of incremental marking finalization steps since creation of
-    // tracer.
-    int cumulative_incremental_marking_finalization_steps;
-
-    // Cumulative pure duration of incremental marking steps since creation of
-    // tracer. (value at start of event)
-    double cumulative_incremental_marking_finalizaton_duration;
-
-    // Longest incremental marking finalization step since start of marking
-    // (start of event).
-    double longest_incremental_marking_finalization_step;
-
-    // Incremental marking finalization steps since
-    // - last event for SCAVENGER events
-    // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR
-    // events
-    int incremental_marking_finalizaton_steps;
-
-    // Duration of incremental marking finalization steps since
-    // - last event for SCAVENGER events
-    // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR
-    // events
-    double incremental_marking_finalization_duration;
-
-    double cumulative_incremental_scopes[Scope::NUMBER_OF_INCREMENTAL_SCOPES];
-
     // Amounts of time spent in different scopes during GC.
     double scopes[Scope::NUMBER_OF_SCOPES];
+
+    // Holds details for incremental marking scopes.
+    IncrementalMarkingInfos
+        incremental_marking_scopes[Scope::NUMBER_OF_INCREMENTAL_SCOPES];
   };
 
   static const int kThroughputTimeFrameMs = 5000;
@@ -315,8 +292,6 @@ class GCTracer {
   // Log an incremental marking step.
   void AddIncrementalMarkingStep(double duration, intptr_t bytes);
 
-  void AddIncrementalMarkingFinalizationStep(double duration);
-
   // Log time spent in marking.
   void AddMarkingTime(double duration) {
     cumulative_marking_duration_ += duration;
@@ -406,7 +381,15 @@ class GCTracer {
   // Discard all recorded survival events.
   void ResetSurvivalEvents();
 
-  void AddScopeSample(Scope::ScopeId scope, double duration);
+  V8_INLINE void AddScopeSample(Scope::ScopeId scope, double duration) {
+    DCHECK(scope < Scope::NUMBER_OF_SCOPES);
+    if (scope >= Scope::FIRST_INCREMENTAL_SCOPE &&
+        scope <= Scope::LAST_INCREMENTAL_SCOPE) {
+      incremental_marking_scopes_[scope].Update(duration);
+    } else {
+      current_.scopes[scope] += duration;
+    }
+  }
 
  private:
   FRIEND_TEST(GCTracer, AverageSpeed);
@@ -415,6 +398,7 @@ class GCTracer {
   FRIEND_TEST(GCTracerTest, NewSpaceAllocationThroughputWithProvidedTime);
   FRIEND_TEST(GCTracerTest, OldGenerationAllocationThroughputWithProvidedTime);
   FRIEND_TEST(GCTracerTest, RegularScope);
+  FRIEND_TEST(GCTracerTest, IncrementalMarkingDetails);
   FRIEND_TEST(GCTracerTest, IncrementalScope);
 
   // Returns the average speed of the events in the buffer.
@@ -424,6 +408,8 @@ class GCTracer {
   static double AverageSpeed(const RingBuffer<BytesAndDuration>& buffer,
                              const BytesAndDuration& initial, double time_ms);
 
+  void MergeBaseline(const Event& baseline);
+
   void ResetForTesting();
 
   // Print one detailed trace line in name=value format.
@@ -438,19 +424,6 @@ class GCTracer {
   // it can be included in later crash dumps.
   void PRINTF_FORMAT(2, 3) Output(const char* format, ...) const;
 
-  void ClearMarkCompactStatistics() {
-    cumulative_incremental_marking_steps_ = 0;
-    cumulative_incremental_marking_bytes_ = 0;
-    cumulative_incremental_marking_duration_ = 0;
-    cumulative_pure_incremental_marking_duration_ = 0;
-    longest_incremental_marking_step_ = 0;
-    cumulative_incremental_marking_finalization_steps_ = 0;
-    cumulative_incremental_marking_finalization_duration_ = 0;
-    longest_incremental_marking_finalization_step_ = 0;
-    cumulative_marking_duration_ = 0;
-    cumulative_sweeping_duration_ = 0;
-  }
-
   double TotalExternalTime() const {
     return current_.scopes[Scope::EXTERNAL_WEAK_GLOBAL_HANDLES] +
            current_.scopes[Scope::MC_EXTERNAL_EPILOGUE] +
@@ -474,9 +447,6 @@ class GCTracer {
   // Previous INCREMENTAL_MARK_COMPACTOR event.
   Event previous_incremental_mark_compactor_event_;
 
-  // Cumulative number of incremental marking steps since creation of tracer.
-  int cumulative_incremental_marking_steps_;
-
   // Cumulative size of incremental marking steps (in bytes) since creation of
   // tracer.
   intptr_t cumulative_incremental_marking_bytes_;
@@ -488,27 +458,14 @@ class GCTracer {
   // tracer.
   double cumulative_pure_incremental_marking_duration_;
 
-  // Longest incremental marking step since start of marking.
-  double longest_incremental_marking_step_;
-
-  // Cumulative number of incremental marking finalization steps since creation
-  // of tracer.
-  int cumulative_incremental_marking_finalization_steps_;
-
-  // Cumulative duration of incremental marking finalization steps since
-  // creation of tracer.
-  double cumulative_incremental_marking_finalization_duration_;
-
-  // Longest incremental marking finalization step since start of marking.
-  double longest_incremental_marking_finalization_step_;
-
   // Total marking time.
   // This timer is precise when run with --print-cumulative-gc-stat
   double cumulative_marking_duration_;
 
-  // Cumulative duration of incremental marking scopes since the creation of
-  // the tracer.
-  double cumulative_incremental_scopes_[Scope::NUMBER_OF_INCREMENTAL_SCOPES];
+  // Incremental scopes carry more information than just the duration. The infos
+  // here are merged back upon starting/stopping the GC tracer.
+  IncrementalMarkingInfos
+      incremental_marking_scopes_[Scope::NUMBER_OF_INCREMENTAL_SCOPES];
 
   // Total sweeping time on the main thread.
   // This timer is precise when run with --print-cumulative-gc-stat