- Fine grain locking of free list when sweeping concurrently.

runtime/vm/pages.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/pages.h"
 
 #include "platform/assert.h"
 #include "vm/compiler_stats.h"
 #include "vm/gc_marker.h"
 #include "vm/gc_sweeper.h"
@@ skipping 704 matching lines @@
       }
       // Advance to the next page.
       page = next_page;
     }
 
     prev_page = NULL;
     page = exec_pages_;
     FreeList* freelist = &freelist_[HeapPage::kExecutable];
     while (page != NULL) {
       HeapPage* next_page = page->next();
-      bool page_in_use = sweeper.SweepPage(page, freelist);
+      bool page_in_use = sweeper.SweepPage(page, freelist, true);
       if (page_in_use) {
         prev_page = page;
       } else {
         FreePage(page, prev_page);
       }
       // Advance to the next page.
       page = next_page;
     }
 
     mid3 = OS::GetCurrentTimeMicros();
 
     if (!FLAG_concurrent_sweep) {
       // Sweep all regular sized pages now.
       prev_page = NULL;
       page = pages_;
       while (page != NULL) {
         HeapPage* next_page = page->next();
-        bool page_in_use = sweeper.SweepPage(page, &freelist_[page->type()]);
+        bool page_in_use = sweeper.SweepPage(
+            page, &freelist_[page->type()], true);
         if (page_in_use) {
           prev_page = page;
         } else {
           FreePage(page, prev_page);
         }
         // Advance to the next page.
         page = next_page;
       }
       if (FLAG_verify_after_gc) {
         OS::PrintErr("Verifying after sweeping...");
@@ skipping 242 matching lines @@
     return 0;
   } else {
     ASSERT(total_time >= gc_time);
     int result= static_cast<int>((static_cast<double>(gc_time) /
                              static_cast<double>(total_time)) * 100);
     return result;
   }
 }
 
 }  // namespace dart