Wait for sweeper threads in EnsureSweeperProgress() only if the main thread finished its sweeping p…

src/spaces.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2535 matching lines @@
     allocation_info_.limit = NULL;
   }
 }
 
 
 bool PagedSpace::EnsureSweeperProgress(intptr_t size_in_bytes) {
   MarkCompactCollector* collector = heap()->mark_compact_collector();
   if (collector->AreSweeperThreadsActivated()) {
     if (collector->IsConcurrentSweepingInProgress()) {
       if (collector->StealMemoryFromSweeperThreads(this) < size_in_bytes) {
-        collector->WaitUntilSweepingCompleted();
-        collector->FinalizeSweeping();
-        return true;
+        if (!collector->sequential_sweeping()) {
+          collector->WaitUntilSweepingCompleted();
+          collector->FinalizeSweeping();
+          return true;
+        }
       }
       return false;
     }
     return true;
   } else {
     return AdvanceSweeper(size_in_bytes);
   }
 }
 
 
@@ skipping 559 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal