[heap] Add concurrency-safe refilling to compaction spaces

src/heap/mark-compact.cc

Index: src/heap/mark-compact.cc
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index f64ed35be1b37b0938c2e6dc74f10aff2f755a08..e0012900b99fb5ce2afc65ab8239ed9294eb4e30 100644
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -547,6 +547,14 @@ void MarkCompactCollector::SweepOrWaitUntilSweepingCompleted(Page* page) {
 }
 
 
+void MarkCompactCollector::SweepAndRefill(CompactionSpace* space) {
+  if (!heap()->concurrent_sweeping_enabled() || !IsSweepingCompleted()) {

[Hannes Payer (out of office), 2015/10/22 11:05:13]

Let's factor this condition out into a separate function, since it is used
somewhere else as well.

[Michael Lippautz, 2015/10/22 12:50:38]

As discussed offline, the condition we want is actually different.

+    SweepInParallel(heap()->paged_space(space->identity()), 0);
+  }
+  space->RefillFreeList();
+}
+
+
 void MarkCompactCollector::EnsureSweepingCompleted() {
   DCHECK(sweeping_in_progress_ == true);