1 /*
   2  * Copyright (c) 2019, Red Hat, Inc. All rights reserved.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 #include "precompiled.hpp"
  25 #include "gc/shenandoah/shenandoahTraversalMode.hpp"
  26 #include "gc/shenandoah/heuristics/shenandoahTraversalHeuristics.hpp"
  27 
  28 void ShenandoahTraversalMode::initialize_flags() const {
  29   FLAG_SET_DEFAULT(ShenandoahSATBBarrier,            false);
  30   FLAG_SET_DEFAULT(ShenandoahStoreValEnqueueBarrier, true);
  31   FLAG_SET_DEFAULT(ShenandoahKeepAliveBarrier,       false);
  32   FLAG_SET_DEFAULT(ShenandoahAllowMixedAllocs,       false);
  33 
  34   SHENANDOAH_ERGO_ENABLE_FLAG(ExplicitGCInvokesConcurrent);
  35   SHENANDOAH_ERGO_ENABLE_FLAG(ShenandoahImplicitGCInvokesConcurrent);
  36 
  37   // Final configuration checks
  38   SHENANDOAH_CHECK_FLAG_SET(ShenandoahLoadRefBarrier);
  39   SHENANDOAH_CHECK_FLAG_SET(ShenandoahStoreValEnqueueBarrier);
  40   SHENANDOAH_CHECK_FLAG_SET(ShenandoahCASBarrier);
  41   SHENANDOAH_CHECK_FLAG_SET(ShenandoahCloneBarrier);
  42 }
  43 
  44 ShenandoahHeuristics* ShenandoahTraversalMode::initialize_heuristics() const {
  45   if (ShenandoahGCHeuristics != NULL) {
  46     if (strcmp(ShenandoahGCHeuristics, "adaptive") == 0) {
  47       return new ShenandoahTraversalHeuristics();
  48     } else {
  49       vm_exit_during_initialization("Unknown -XX:ShenandoahGCHeuristics option");
  50     }
  51   }
  52   ShouldNotReachHere();
  53   return NULL;
  54 }