src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp

rev 2870 : 7117303: VM uses non-monotonic time source and complains that it is non-monotonic
Summary: Replaces calls to os::javaTimeMillis(), which does not guarantee montonicity, in GC code to os::javaTimeNanos() with a suitable conversion factor. os::javaTimeNanos is guaranteed monotonic if the underlying platform provides a monotonic timesource. Changes in OS files are to make use of the newly defined constants in globalDefinitions.hpp.
Reviewed-by: dholmes

*** 3396,3416 ****
             "live objects skipped because closure is full");
    }
  }
  
  jlong PSParallelCompact::millis_since_last_gc() {
!   jlong ret_val = os::javaTimeMillis() - _time_of_last_gc;
    // XXX See note in genCollectedHeap::millis_since_last_gc().
    if (ret_val < 0) {
!     NOT_PRODUCT(warning("time warp: %d", ret_val);)
      return 0;
    }
    return ret_val;
  }
  
  void PSParallelCompact::reset_millis_since_last_gc() {
!   _time_of_last_gc = os::javaTimeMillis();
  }
  
  ParMarkBitMap::IterationStatus MoveAndUpdateClosure::copy_until_full()
  {
    if (source() != destination()) {
--- 3396,3421 ----
             "live objects skipped because closure is full");
    }
  }
  
  jlong PSParallelCompact::millis_since_last_gc() {
!   // We need a montonically increasing time in ms but os::javaTimeMillis()
!   // does not guarantee montonicity.
!   jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
!   jlong ret_val = now - _time_of_last_gc;
    // XXX See note in genCollectedHeap::millis_since_last_gc().
    if (ret_val < 0) {
!     NOT_PRODUCT(warning("time warp: "INT64_FORMAT, ret_val);)
      return 0;
    }
    return ret_val;
  }
  
  void PSParallelCompact::reset_millis_since_last_gc() {
!   // We need a montonically increasing time in ms but os::javaTimeMillis()
!   // does not guarantee montonicity.
!   _time_of_last_gc = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
  }
  
  ParMarkBitMap::IterationStatus MoveAndUpdateClosure::copy_until_full()
  {
    if (source() != destination()) {