1 /*
   2  * Copyright (c) 2016, 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_SHENANDOAHTASKQUEUE_INLINE_HPP
  25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHTASKQUEUE_INLINE_HPP
  26 
  27 #include "gc_implementation/shenandoah/shenandoahHeap.inline.hpp"
  28 #include "utilities/stack.inline.hpp"
  29 
  30 template <class E, MEMFLAGS F, unsigned int N>
  31 bool BufferedOverflowTaskQueue<E, F, N>::pop(E &t) {
  32   if (!_buf_empty) {
  33     t = _elem;
  34     _buf_empty = true;
  35     return true;
  36   }
  37 
  38   if (taskqueue_t::pop_local(t)) {
  39     return true;
  40   }
  41 
  42   return taskqueue_t::pop_overflow(t);
  43 }
  44 
  45 template <class E, MEMFLAGS F, unsigned int N>
  46 inline bool BufferedOverflowTaskQueue<E, F, N>::push(E t) {
  47   if (_buf_empty) {
  48     _elem = t;
  49     _buf_empty = false;
  50   } else {
  51     bool pushed = taskqueue_t::push(_elem);
  52     assert(pushed, "overflow queue should always succeed pushing");
  53     _elem = t;
  54   }
  55   return true;
  56 }
  57 
  58 template <class E, MEMFLAGS F, unsigned int N>
  59 void BufferedOverflowTaskQueue<E, F, N>::clear() {
  60   _buf_empty = true;
  61   taskqueue_t::set_empty();
  62   taskqueue_t::overflow_stack()->clear();
  63 }
  64 
  65 
  66 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHTASKQUEUE_HPP