src/share/vm/runtime/globals.hpp

*** 1553,1562 ****
--- 1553,1566 ----
            range(0, 100)                                                     \
                                                                              \
    product(uint, ParallelGCThreads, 0,                                       \
            "Number of parallel threads parallel gc will use")                \
                                                                              \
+   diagnostic(bool, UseSemaphoreGCThreadsSynchronization, true,              \
+             "Use semaphore synchronization for the GC Threads, "            \
+             "instead of synchronization based on mutexes")                  \
+                                                                             \
    product(bool, UseDynamicNumberOfGCThreads, false,                         \
            "Dynamically choose the number of parallel threads "              \
            "parallel gc will use")                                           \
                                                                              \
    diagnostic(bool, ForceDynamicNumberOfGCThreads, false,                    \