Set unswept free bytes for concurent sweeper.

src/spaces.h

Index: src/spaces.h
diff --git a/src/spaces.h b/src/spaces.h
index 07daacfdf63d7c530f9694544435a4c1275121fc..cc536d1897a978a06d5832f4d5fa6df180396b71 100644
--- a/src/spaces.h
+++ b/src/spaces.h
@@ -1751,11 +1751,19 @@ class PagedSpace : public Space {
     unswept_free_bytes_ += (p->area_size() - p->LiveBytes());
   }
 
+  void DecreaseUnsweptFreeBytes(int by) {

[Michael Starzinger, 2013/02/28 13:09:52]

Let's rename this to DecrementUnsweptFreeBytes() which is in line with the other
names.

[Hannes Payer (out of office), 2013/02/28 14:42:34]

Done.

+    unswept_free_bytes_ -= by;
+  }
+
   void DecreaseUnsweptFreeBytes(Page* p) {
     ASSERT(ShouldBeSweptLazily(p));
     unswept_free_bytes_ -= (p->area_size() - p->LiveBytes());
   }
 
+  void ResetUnsweptFreeBytes() {
+    unswept_free_bytes_ = 0;
+  }
+
   bool AdvanceSweeper(intptr_t bytes_to_sweep);
 
   // When parallel sweeper threads are active this function waits