1 /*
   2  * Copyright (c) 2017, 2018, 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_SHENANDOAHWORKGROUP_HPP
  25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHWORKGROUP_HPP
  26 
  27 #include "gc/shared/workgroup.hpp"
  28 #include "gc/shenandoah/shenandoahTaskqueue.hpp"
  29 #include "memory/allocation.hpp"
  30 
  31 class ShenandoahObjToScanQueueSet;
  32 
  33 class ShenandoahWorkerScope : public StackObj {
  34 private:
  35   uint      _n_workers;
  36   WorkGang* _workers;
  37 public:
  38   ShenandoahWorkerScope(WorkGang* workers, uint nworkers, const char* msg, bool do_check = true);
  39   ~ShenandoahWorkerScope();
  40 };
  41 
  42 class ShenandoahPushWorkerScope : StackObj {
  43 protected:
  44   uint      _n_workers;
  45   uint      _old_workers;
  46   WorkGang* _workers;
  47 
  48 public:
  49   ShenandoahPushWorkerScope(WorkGang* workers, uint nworkers, bool do_check = true);
  50   ~ShenandoahPushWorkerScope();
  51 };
  52 
  53 class ShenandoahPushWorkerQueuesScope : public ShenandoahPushWorkerScope {
  54 private:
  55   ShenandoahObjToScanQueueSet* _queues;
  56 
  57 public:
  58   ShenandoahPushWorkerQueuesScope(WorkGang* workers, ShenandoahObjToScanQueueSet* queues, uint nworkers, bool do_check = true);
  59   ~ShenandoahPushWorkerQueuesScope();
  60 };
  61 
  62 class ShenandoahWorkGang : public WorkGang {
  63 private:
  64   bool     _initialize_gclab;
  65 public:
  66   ShenandoahWorkGang(const char* name,
  67            uint workers,
  68            bool are_GC_task_threads,
  69            bool are_ConcurrentGC_threads) :
  70     WorkGang(name, workers, are_GC_task_threads, are_ConcurrentGC_threads), _initialize_gclab(false) {
  71     }
  72 
  73   // Create a GC worker and install it into the work gang.
  74   // We need to initialize gclab for dynamic allocated workers
  75   AbstractGangWorker* install_worker(uint which);
  76 
  77   // We allow _active_workers < _total_workers when UseDynamicNumberOfGCThreads is off.
  78   // We use the same WorkGang for concurrent and parallel processing, and honor
  79   // ConcGCThreads and ParallelGCThreads settings
  80   virtual uint active_workers() const {
  81     assert(_active_workers > 0, "no active worker");
  82     assert(_active_workers <= _total_workers,
  83            "_active_workers: %u > _total_workers: %u", _active_workers, _total_workers);
  84     return _active_workers;
  85   }
  86 
  87   void set_initialize_gclab() { assert(!_initialize_gclab, "Can only enable once"); _initialize_gclab = true; }
  88 };
  89 
  90 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHWORKGROUP_HPP