- Stop-the-world sweep uses pre-locked free list access.

runtime/vm/gc_sweeper.cc

Index: runtime/vm/gc_sweeper.cc
===================================================================
--- runtime/vm/gc_sweeper.cc	(revision 39397)
+++ runtime/vm/gc_sweeper.cc	(working copy)
@@ -45,7 +45,7 @@
       }
       if ((current != start) || (free_end != end)) {
         // Only add to the free list if not covering the whole page.
-        freelist->Free(current, obj_size);
+        freelist->FreeLocked(current, obj_size);

[koda, 2014/08/20 13:52:22]

SweepPage now assumes that 'freelist' is locked, so you should document this
precondition in the method's specification.

[Ivan Posva, 2014/08/20 14:10:20]

Done.

       }
     }
     current += obj_size;