1 /*
   2  * Copyright (c) 2013, 2017, Red Hat, Inc. and/or its affiliates.
   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 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHCOLLECTORPOLICY_HPP
  25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHCOLLECTORPOLICY_HPP
  26 
  27 #include "gc/shared/gcTrace.hpp"
  28 #include "gc/shared/gcTimer.hpp"
  29 #include "gc/shared/collectorPolicy.hpp"
  30 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
  31 #include "gc/shenandoah/shenandoahHeap.hpp"
  32 #include "runtime/arguments.hpp"
  33 #include "utilities/numberSeq.hpp"
  34 
  35 class ShenandoahCollectionSet;
  36 class ShenandoahConnectionMatrix;
  37 class ShenandoahFreeSet;
  38 class ShenandoahHeap;
  39 class ShenandoahHeuristics;
  40 class outputStream;
  41 
  42 class ShenandoahCollectorPolicy: public CollectorPolicy {
  43 private:
  44   size_t _success_concurrent_gcs;
  45   size_t _success_degenerated_gcs;
  46   size_t _success_full_gcs;
  47   size_t _alloc_failure_degenerated;
  48   size_t _alloc_failure_degenerated_upgrade_to_full;
  49   size_t _alloc_failure_full;
  50   size_t _explicit_concurrent;
  51   size_t _explicit_full;
  52   size_t _degen_points[ShenandoahHeap::_DEGENERATED_LIMIT];
  53 
  54   ShenandoahSharedFlag _in_shutdown;
  55 
  56   ShenandoahHeuristics* _heuristics;
  57   ShenandoahTracer* _tracer;
  58 
  59   size_t _cycle_counter;
  60 
  61 
  62 public:
  63   ShenandoahCollectorPolicy();
  64 
  65   virtual ShenandoahCollectorPolicy* as_pgc_policy();
  66 
  67   BarrierSet::Name barrier_set_name();
  68 
  69   HeapWord* mem_allocate_work(size_t size,
  70                               bool is_tlab,
  71                               bool* gc_overhead_limit_was_exceeded);
  72 
  73   HeapWord* satisfy_failed_allocation(size_t size, bool is_tlab);
  74 
  75   void initialize_alignments();
  76 
  77   void post_heap_initialize();
  78 
  79   void record_gc_start();
  80   void record_gc_end();
  81   ShenandoahHeuristics* heuristics() { return _heuristics;}
  82   // TODO: This is different from gc_end: that one encompasses one VM operation.
  83   // These two encompass the entire cycle.
  84   void record_cycle_start();
  85   void record_cycle_end();
  86 
  87   void record_phase_time(ShenandoahPhaseTimings::Phase phase, double secs);
  88 
  89   void record_success_concurrent();
  90   void record_success_degenerated();
  91   void record_success_full();
  92   void record_alloc_failure_to_degenerated(ShenandoahHeap::ShenandoahDegenPoint point);
  93   void record_alloc_failure_to_full();
  94   void record_degenerated_upgrade_to_full();
  95   void record_explicit_to_concurrent();
  96   void record_explicit_to_full();
  97 
  98   bool should_start_normal_gc();
  99   ShenandoahHeap::GCCycleMode should_start_traversal_gc();
 100   bool can_do_traversal_gc();
 101 
 102   // Returns true when there should be a separate concurrent reference
 103   // updating phase after evacuation.
 104   bool should_start_update_refs();
 105   bool update_refs();
 106 
 107   bool should_degenerate_cycle();
 108 
 109 
 110   void record_peak_occupancy();
 111 
 112   void record_shutdown();
 113   bool is_at_shutdown();
 114 
 115   void choose_collection_set(ShenandoahCollectionSet* collection_set,
 116                              bool minor = false);
 117 
 118   bool should_process_references();
 119   bool should_unload_classes();
 120 
 121   ShenandoahTracer* tracer() {return _tracer;}
 122 
 123   size_t cycle_counter() const;
 124 
 125   void print_gc_stats(outputStream* out) const;
 126 };
 127 
 128 
 129 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHCOLLECTORPOLICY_HPP