[heap] Abort AdvanceIncrementalMarking when we do not make marking progress.

src/heap/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/heap/incremental-marking.h"
 
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
 #include "src/conversions.h"
 #include "src/heap/gc-idle-time-handler.h"
@@ skipping 1012 matching lines @@
 
   if (step_size_in_bytes == 0) {
     step_size_in_bytes = GCIdleTimeHandler::EstimateMarkingStepSize(
         GCIdleTimeHandler::kIncrementalMarkingStepTimeInMs,
         heap()
             ->tracer()
             ->FinalIncrementalMarkCompactSpeedInBytesPerMillisecond());
   }
 
   double remaining_time_in_ms = 0.0;
+  intptr_t bytes_processed = 0;
   do {
-    Step(step_size_in_bytes, step_actions.completion_action,
-         step_actions.force_marking, step_actions.force_completion);
+    bytes_processed =
+        Step(step_size_in_bytes, step_actions.completion_action,
+             step_actions.force_marking, step_actions.force_completion);
     remaining_time_in_ms =
         deadline_in_ms - heap()->MonotonicallyIncreasingTimeInMs();
-  } while (remaining_time_in_ms >=
+  } while (bytes_processed > 0 &&
+           remaining_time_in_ms >=
                2.0 * GCIdleTimeHandler::kIncrementalMarkingStepTimeInMs &&
            !IsComplete() &&
            !heap()->mark_compact_collector()->marking_deque()->IsEmpty());
   return remaining_time_in_ms;
 }
 
 
 void IncrementalMarking::OldSpaceStep(intptr_t allocated) {
   if (IsStopped() && ShouldActivateEvenWithoutIdleNotification()) {
     heap()->StartIncrementalMarking(Heap::kNoGCFlags, kNoGCCallbackFlags,
@@ skipping 127 matching lines @@
     if (state_ == SWEEPING) {
       if (heap_->mark_compact_collector()->sweeping_in_progress() &&
           (heap_->mark_compact_collector()->IsSweepingCompleted() ||
            !FLAG_concurrent_sweeping)) {
         heap_->mark_compact_collector()->EnsureSweepingCompleted();
       }
       if (!heap_->mark_compact_collector()->sweeping_in_progress()) {
         bytes_scanned_ = 0;
         StartMarking();
       }
-    } else if (state_ == MARKING) {

[Hannes Payer (out of office), 2016/04/01 12:48:24]

This is a slight policy change. However, I don't think there is much harm when
we do steps after sweeping.

+    }
+    if (state_ == MARKING) {
       bytes_processed = ProcessMarkingDeque(bytes_to_process);
       if (heap_->mark_compact_collector()->marking_deque()->IsEmpty()) {
         if (completion == FORCE_COMPLETION ||
             IsIdleMarkingDelayCounterLimitReached()) {
           if (!finalize_marking_completed_) {
             FinalizeMarking(action);
           } else {
             MarkingComplete(action);
           }
         } else {
@@ skipping 45 matching lines @@
 void IncrementalMarking::IncrementIdleMarkingDelayCounter() {
   idle_marking_delay_counter_++;
 }
 
 
 void IncrementalMarking::ClearIdleMarkingDelayCounter() {
   idle_marking_delay_counter_ = 0;
 }
 }  // namespace internal
 }  // namespace v8