1 /*
   2  * Copyright (c) 2013, 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 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_HPP
  25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_HPP
  26 
  27 #include "utilities/taskqueue.hpp"
  28 #include "gc_implementation/shenandoah/shenandoahOopClosures.hpp"
  29 #include "gc_implementation/shenandoah/shenandoahTaskqueue.hpp"
  30 #include "gc_implementation/shenandoah/shenandoahPhaseTimings.hpp"
  31 
  32 class ShenandoahStrDedupQueue;
  33 
  34 class ShenandoahConcurrentMark: public CHeapObj<mtGC> {
  35 private:
  36   ShenandoahHeap* _heap;
  37   ShenandoahObjToScanQueueSet* _task_queues;
  38 
  39 public:
  40   void initialize(uint workers);
  41   void cancel();
  42 
  43 // ---------- Marking loop and tasks
  44 //
  45 private:
  46   template <class T>
  47   inline void do_task(ShenandoahObjToScanQueue* q, T* cl, ShenandoahLiveData* live_data, ShenandoahMarkTask* task);
  48 
  49   template <class T>
  50   inline void do_chunked_array_start(ShenandoahObjToScanQueue* q, T* cl, oop array);
  51 
  52   template <class T>
  53   inline void do_chunked_array(ShenandoahObjToScanQueue* q, T* cl, oop array, int chunk, int pow);
  54 
  55   inline void count_liveness(ShenandoahLiveData* live_data, oop obj);
  56 
  57   template <class T, bool CANCELLABLE>
  58   void mark_loop_work(T* cl, ShenandoahLiveData* live_data, uint worker_id, ShenandoahTaskTerminator *t);
  59 
  60   template <bool CANCELLABLE>
  61   void mark_loop_prework(uint worker_id, ShenandoahTaskTerminator *terminator, ReferenceProcessor *rp, bool strdedup);
  62 
  63 public:
  64   void mark_loop(uint worker_id, ShenandoahTaskTerminator* terminator, ReferenceProcessor *rp,
  65                  bool cancellable, bool strdedup) {
  66     if (cancellable) {
  67       mark_loop_prework<true>(worker_id, terminator, rp, strdedup);
  68     } else {
  69       mark_loop_prework<false>(worker_id, terminator, rp, strdedup);
  70     }
  71   }
  72 
  73   template<class T, UpdateRefsMode UPDATE_REFS, StringDedupMode STRING_DEDUP>
  74   static inline void mark_through_ref(T* p, ShenandoahHeap* heap, ShenandoahObjToScanQueue* q, ShenandoahMarkingContext* const mark_context, ShenandoahStrDedupQueue* dq = NULL);
  75 
  76   void mark_from_roots();
  77   void finish_mark_from_roots(bool full_gc);
  78 
  79   void mark_roots(ShenandoahPhaseTimings::Phase root_phase);
  80   void update_roots(ShenandoahPhaseTimings::Phase root_phase);
  81   void update_thread_roots(ShenandoahPhaseTimings::Phase root_phase);
  82 
  83 // ---------- Weak references
  84 //
  85 private:
  86   void weak_refs_work(bool full_gc);
  87   void weak_refs_work_doit(bool full_gc);
  88 
  89 public:
  90   void weak_roots_work(bool full_gc);
  91   void preclean_weak_refs();
  92 
  93 // ---------- Concurrent code cache
  94 //
  95 private:
  96   ShenandoahSharedFlag _claimed_codecache;
  97 
  98 public:
  99   void concurrent_scan_code_roots(uint worker_id, ReferenceProcessor* rp);
 100   bool claim_codecache();
 101   void clear_claim_codecache();
 102 
 103 // ---------- Helpers
 104 // Used from closures, need to be public
 105 //
 106 public:
 107   ShenandoahObjToScanQueue* get_queue(uint worker_id);
 108   ShenandoahObjToScanQueueSet* task_queues() { return _task_queues; }
 109 
 110 };
 111 
 112 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_HPP