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1 /* |
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2 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved. |
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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4 * |
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5 * This code is free software; you can redistribute it and/or modify it |
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6 * under the terms of the GNU General Public License version 2 only, as |
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7 * published by the Free Software Foundation. |
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8 * |
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9 * This code is distributed in the hope that it will be useful, but WITHOUT |
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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12 * version 2 for more details (a copy is included in the LICENSE file that |
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13 * accompanied this code). |
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14 * |
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15 * You should have received a copy of the GNU General Public License version |
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16 * 2 along with this work; if not, write to the Free Software Foundation, |
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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18 * |
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
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22 */ |
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23 |
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24 #ifndef SHARE_GC_Z_ZMARKTERMINATE_INLINE_HPP |
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25 #define SHARE_GC_Z_ZMARKTERMINATE_INLINE_HPP |
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26 |
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27 #include "runtime/atomic.hpp" |
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28 #include "runtime/orderAccess.hpp" |
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29 |
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30 inline ZMarkTerminate::ZMarkTerminate() : |
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31 _nworkers(0), |
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32 _nworking_stage0(0), |
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33 _nworking_stage1(0) {} |
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34 |
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35 inline bool ZMarkTerminate::enter_stage(volatile uint* nworking_stage) { |
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36 return Atomic::sub(1u, nworking_stage) == 0; |
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37 } |
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38 |
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39 inline void ZMarkTerminate::exit_stage(volatile uint* nworking_stage) { |
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40 Atomic::add(1u, nworking_stage); |
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41 } |
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42 |
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43 inline bool ZMarkTerminate::try_exit_stage(volatile uint* nworking_stage) { |
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44 uint nworking = Atomic::load(nworking_stage); |
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45 |
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46 for (;;) { |
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47 if (nworking == 0) { |
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48 return false; |
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49 } |
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50 |
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51 const uint new_nworking = nworking + 1; |
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52 const uint prev_nworking = Atomic::cmpxchg(new_nworking, nworking_stage, nworking); |
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53 if (prev_nworking == nworking) { |
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54 // Success |
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55 return true; |
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56 } |
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57 |
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58 // Retry |
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59 nworking = prev_nworking; |
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60 } |
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61 } |
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62 |
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63 inline void ZMarkTerminate::reset(uint nworkers) { |
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64 _nworkers = _nworking_stage0 = _nworking_stage1 = nworkers; |
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65 } |
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66 |
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67 inline bool ZMarkTerminate::enter_stage0() { |
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68 return enter_stage(&_nworking_stage0); |
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69 } |
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70 |
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71 inline void ZMarkTerminate::exit_stage0() { |
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72 exit_stage(&_nworking_stage0); |
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73 } |
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74 |
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75 inline bool ZMarkTerminate::try_exit_stage0() { |
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76 return try_exit_stage(&_nworking_stage0); |
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77 } |
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78 |
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79 inline bool ZMarkTerminate::enter_stage1() { |
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80 return enter_stage(&_nworking_stage1); |
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81 } |
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82 |
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83 inline bool ZMarkTerminate::try_exit_stage1() { |
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84 return try_exit_stage(&_nworking_stage1); |
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85 } |
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86 |
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87 #endif // SHARE_GC_Z_ZMARKTERMINATE_INLINE_HPP |