Always trace garbage collection events in GCTracer.

src/incremental-marking.cc

 // Copyright 2012 the V8 project 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 "src/v8.h"
 
 #include "src/incremental-marking.h"
 
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
@@ skipping 848 matching lines @@
   // barriers before we get here and check them (marking can only take place on
   // allocation), so to reduce the lumpiness we don't use the write barriers
   // invoked since last step directly to determine the amount of work to do.
   intptr_t bytes_to_process =
       marking_speed_ * Max(allocated_, write_barriers_invoked_since_last_step_);
   allocated_ = 0;
   write_barriers_invoked_since_last_step_ = 0;
 
   bytes_scanned_ += bytes_to_process;
 
-  double start = 0;
-
-  if (FLAG_trace_incremental_marking || FLAG_trace_gc ||
-      FLAG_print_cumulative_gc_stat) {
-    start = base::OS::TimeCurrentMillis();
-  }
+  double start = base::OS::TimeCurrentMillis();
 
   if (state_ == SWEEPING) {
     if (heap_->mark_compact_collector()->sweeping_in_progress() &&
         heap_->mark_compact_collector()->IsSweepingCompleted()) {
       heap_->mark_compact_collector()->EnsureSweepingCompleted();
     }
     if (!heap_->mark_compact_collector()->sweeping_in_progress()) {
       bytes_scanned_ = 0;
       StartMarking(PREVENT_COMPACTION);
     }
@@ skipping 60 matching lines @@
       marking_speed_ += kMarkingSpeedAccelleration;
       marking_speed_ = static_cast<int>(
           Min(kMaxMarkingSpeed,
               static_cast<intptr_t>(marking_speed_ * 1.3)));
       if (FLAG_trace_gc) {
         PrintPID("Marking speed increased to %d\n", marking_speed_);
       }
     }
   }
 
-  if (FLAG_trace_incremental_marking || FLAG_trace_gc ||
-      FLAG_print_cumulative_gc_stat) {
-    double end = base::OS::TimeCurrentMillis();
-    double delta = (end - start);
-    heap_->tracer()->AddIncrementalMarkingStep(delta);
-    heap_->AddMarkingTime(delta);
-  }
+  double end = base::OS::TimeCurrentMillis();
+  double delta = (end - start);
+  heap_->tracer()->AddIncrementalMarkingStep(delta);
+  heap_->AddMarkingTime(delta);
 }
 
 
 void IncrementalMarking::ResetStepCounters() {
   steps_count_ = 0;
   old_generation_space_available_at_start_of_incremental_ =
       SpaceLeftInOldSpace();
   old_generation_space_used_at_start_of_incremental_ =
       heap_->PromotedTotalSize();
   bytes_rescanned_ = 0;
   marking_speed_ = kInitialMarkingSpeed;
   bytes_scanned_ = 0;
   write_barriers_invoked_since_last_step_ = 0;
 }
 
 
 int64_t IncrementalMarking::SpaceLeftInOldSpace() {
   return heap_->MaxOldGenerationSize() - heap_->PromotedSpaceSizeOfObjects();
 }
 
 } }  // namespace v8::internal