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 #include "precompiled.hpp"
  25 
  26 #include "gc/shared/workerPolicy.hpp"
  27 #include "gc/shenandoah/shenandoahWorkerPolicy.hpp"
  28 #include "runtime/thread.hpp"
  29 
  30 uint ShenandoahWorkerPolicy::_prev_par_marking     = 0;
  31 uint ShenandoahWorkerPolicy::_prev_conc_marking    = 0;
  32 uint ShenandoahWorkerPolicy::_prev_conc_evac       = 0;
  33 uint ShenandoahWorkerPolicy::_prev_fullgc          = 0;
  34 uint ShenandoahWorkerPolicy::_prev_degengc         = 0;
  35 uint ShenandoahWorkerPolicy::_prev_stw_traversal   = 0;
  36 uint ShenandoahWorkerPolicy::_prev_conc_traversal  = 0;
  37 uint ShenandoahWorkerPolicy::_prev_conc_update_ref = 0;
  38 uint ShenandoahWorkerPolicy::_prev_par_update_ref  = 0;
  39 uint ShenandoahWorkerPolicy::_prev_conc_cleanup    = 0;
  40 uint ShenandoahWorkerPolicy::_prev_conc_reset      = 0;
  41 
  42 uint ShenandoahWorkerPolicy::calc_workers_for_init_marking() {
  43   uint active_workers = (_prev_par_marking == 0) ? ParallelGCThreads : _prev_par_marking;
  44 
  45   _prev_par_marking =
  46     WorkerPolicy::calc_active_workers(ParallelGCThreads,
  47                                       active_workers,
  48                                       Threads::number_of_non_daemon_threads());
  49   return _prev_par_marking;
  50 }
  51 
  52 uint ShenandoahWorkerPolicy::calc_workers_for_conc_marking() {
  53   uint active_workers = (_prev_conc_marking == 0) ?  ConcGCThreads : _prev_conc_marking;
  54   _prev_conc_marking =
  55     WorkerPolicy::calc_active_conc_workers(ConcGCThreads,
  56                                            active_workers,
  57                                            Threads::number_of_non_daemon_threads());
  58   return _prev_conc_marking;
  59 }
  60 
  61 // Reuse the calculation result from init marking
  62 uint ShenandoahWorkerPolicy::calc_workers_for_final_marking() {
  63   return _prev_par_marking;
  64 }
  65 
  66 // Calculate workers for concurrent evacuation (concurrent GC)
  67 uint ShenandoahWorkerPolicy::calc_workers_for_conc_evac() {
  68   uint active_workers = (_prev_conc_evac == 0) ? ConcGCThreads : _prev_conc_evac;
  69   _prev_conc_evac =
  70     WorkerPolicy::calc_active_conc_workers(ConcGCThreads,
  71                                            active_workers,
  72                                            Threads::number_of_non_daemon_threads());
  73   return _prev_conc_evac;
  74 }
  75 
  76 // Calculate workers for parallel fullgc
  77 uint ShenandoahWorkerPolicy::calc_workers_for_fullgc() {
  78   uint active_workers = (_prev_fullgc == 0) ?  ParallelGCThreads : _prev_fullgc;
  79   _prev_fullgc =
  80     WorkerPolicy::calc_active_workers(ParallelGCThreads,
  81                                       active_workers,
  82                                       Threads::number_of_non_daemon_threads());
  83   return _prev_fullgc;
  84 }
  85 
  86 // Calculate workers for parallel degenerated gc
  87 uint ShenandoahWorkerPolicy::calc_workers_for_stw_degenerated() {
  88   uint active_workers = (_prev_degengc == 0) ?  ParallelGCThreads : _prev_degengc;
  89   _prev_degengc =
  90     WorkerPolicy::calc_active_workers(ParallelGCThreads,
  91                                       active_workers,
  92                                       Threads::number_of_non_daemon_threads());
  93   return _prev_degengc;
  94 }
  95 
  96 // Calculate workers for Stop-the-world traversal GC
  97 uint ShenandoahWorkerPolicy::calc_workers_for_stw_traversal() {
  98   uint active_workers = (_prev_stw_traversal == 0) ? ParallelGCThreads : _prev_stw_traversal;
  99   _prev_stw_traversal =
 100     WorkerPolicy::calc_active_workers(ParallelGCThreads,
 101                                       active_workers,
 102                                       Threads::number_of_non_daemon_threads());
 103   return _prev_stw_traversal;
 104 }
 105 
 106 // Calculate workers for concurent traversal GC
 107 uint ShenandoahWorkerPolicy::calc_workers_for_conc_traversal() {
 108   uint active_workers = (_prev_conc_traversal == 0) ? ConcGCThreads : _prev_conc_traversal;
 109   _prev_conc_traversal =
 110     WorkerPolicy::calc_active_conc_workers(ConcGCThreads,
 111                                            active_workers,
 112                                            Threads::number_of_non_daemon_threads());
 113   return _prev_conc_traversal;
 114 }
 115 
 116 // Calculate workers for concurrent reference update
 117 uint ShenandoahWorkerPolicy::calc_workers_for_conc_update_ref() {
 118   uint active_workers = (_prev_conc_update_ref == 0) ? ConcGCThreads : _prev_conc_update_ref;
 119   _prev_conc_update_ref =
 120     WorkerPolicy::calc_active_conc_workers(ConcGCThreads,
 121                                            active_workers,
 122                                            Threads::number_of_non_daemon_threads());
 123   return _prev_conc_update_ref;
 124 }
 125 
 126 // Calculate workers for parallel reference update
 127 uint ShenandoahWorkerPolicy::calc_workers_for_final_update_ref() {
 128   uint active_workers = (_prev_par_update_ref == 0) ? ParallelGCThreads : _prev_par_update_ref;
 129   _prev_par_update_ref =
 130     WorkerPolicy::calc_active_workers(ParallelGCThreads,
 131                                       active_workers,
 132                                       Threads::number_of_non_daemon_threads());
 133   return _prev_par_update_ref;
 134 }
 135 
 136 uint ShenandoahWorkerPolicy::calc_workers_for_conc_preclean() {
 137   // Precleaning is single-threaded
 138   return 1;
 139 }
 140 
 141 uint ShenandoahWorkerPolicy::calc_workers_for_conc_cleanup() {
 142   uint active_workers = (_prev_conc_cleanup == 0) ? ConcGCThreads : _prev_conc_cleanup;
 143   _prev_conc_cleanup =
 144           WorkerPolicy::calc_active_conc_workers(ConcGCThreads,
 145                                                  active_workers,
 146                                                  Threads::number_of_non_daemon_threads());
 147   return _prev_conc_cleanup;
 148 }
 149 
 150 uint ShenandoahWorkerPolicy::calc_workers_for_conc_reset() {
 151   uint active_workers = (_prev_conc_reset == 0) ? ConcGCThreads : _prev_conc_reset;
 152   _prev_conc_reset =
 153           WorkerPolicy::calc_active_conc_workers(ConcGCThreads,
 154                                                  active_workers,
 155                                                  Threads::number_of_non_daemon_threads());
 156   return _prev_conc_reset;
 157 }