projects / urcu.git / blame
| Commit | Line | Data |
|---|---|---|
| d4de4869 MD |
1 | /* |
| 2 | * futex.spin: Promela code to validate futex wakeup algorithm. | |
| 3 | * | |
| 4 | * Algorithm verified : | |
| 5 | * | |
| 6 | * queue = 0; | |
| 7 | * fut = 0; | |
| 8 | * runvar = 0; | |
| 9 | * | |
| 10 | * Waker | |
| 11 | * queue = 1; | |
| 12 | * if (fut == -1) { | |
| 13 | * fut = 0; | |
| 14 | * } | |
| 15 | * | |
| 16 | * Waiter | |
| 17 | * while (1) { | |
| 18 | * progress: | |
| 19 | * fut = fut - 1; | |
| 20 | * if (queue == 1) { | |
| 21 | * fut = 0; | |
| 22 | * } else { | |
| 23 | * if (fut == -1) { | |
| 24 | * while (fut == -1) { } | |
| 25 | * } | |
| 26 | * } | |
| 27 | * queue = 0; | |
| 28 | * } | |
| 29 | * | |
| 30 | * if queue = 1, then !_np | |
| 31 | * | |
| 32 | * This program is free software; you can redistribute it and/or modify | |
| 33 | * it under the terms of the GNU General Public License as published by | |
| 34 | * the Free Software Foundation; either version 2 of the License, or | |
| 35 | * (at your option) any later version. | |
| 36 | * | |
| 37 | * This program is distributed in the hope that it will be useful, | |
| 38 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 39 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 40 | * GNU General Public License for more details. | |
| 41 | * | |
| 42 | * You should have received a copy of the GNU General Public License | |
| 43 | * along with this program; if not, write to the Free Software | |
| 44 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
| 45 | * | |
| 46 | * Copyright (c) 2009 Mathieu Desnoyers | |
| 47 | */ | |
| 48 | ||
| 29f38067 MD |
49 | #define get_pid() (_pid) |
| 50 | ||
| 51 | int queue[2] = 0; | |
| d4de4869 MD |
52 | int fut = 0; |
| 53 | ||
| 29f38067 | 54 | active [2] proctype waker() |
| d4de4869 | 55 | { |
| 29f38067 MD |
56 | assert(get_pid() < 2); |
| 57 | ||
| 58 | queue[get_pid()] = 1; | |
| d4de4869 MD |
59 | |
| 60 | if | |
| 61 | :: (fut == -1) -> | |
| 62 | fut = 0; | |
| 63 | :: else -> | |
| 64 | skip; | |
| 65 | fi; | |
| 66 | ||
| 29f38067 | 67 | queue[get_pid()] = 1; |
| d4de4869 MD |
68 | |
| 69 | if | |
| 70 | :: (fut == -1) -> | |
| 71 | fut = 0; | |
| 72 | :: else -> | |
| 73 | skip; | |
| 74 | fi; | |
| 75 | ||
| 76 | #ifdef INJ_QUEUE_NO_WAKE | |
| 29f38067 | 77 | queue[get_pid()] = 1; |
| d4de4869 MD |
78 | #endif |
| 79 | } | |
| 80 | ||
| 81 | ||
| 82 | active proctype waiter() | |
| 83 | { | |
| 84 | do | |
| 85 | :: 1 -> | |
| 86 | #ifndef INJ_LATE_DEC | |
| 87 | fut = fut - 1; | |
| 88 | #endif | |
| 89 | if | |
| 29f38067 | 90 | :: (queue[0] == 1 || queue[1] == 1) -> |
| d4de4869 MD |
91 | #ifndef INJ_LATE_DEC |
| 92 | fut = 0; | |
| 93 | #endif | |
| 94 | skip; | |
| 95 | :: else -> | |
| 96 | #ifdef INJ_LATE_DEC | |
| 97 | fut = fut - 1; | |
| 98 | #endif | |
| 99 | if | |
| 100 | :: (fut == -1) -> | |
| 101 | do | |
| 102 | :: 1 -> | |
| 103 | if | |
| 104 | :: (fut == -1) -> | |
| d4de4869 MD |
105 | skip; |
| 106 | :: else -> | |
| 107 | break; | |
| 108 | fi; | |
| 109 | od; | |
| 110 | :: else -> | |
| 111 | skip; | |
| 112 | fi; | |
| 113 | fi; | |
| 9b35d5dc | 114 | progress: |
| 29f38067 MD |
115 | if |
| 116 | :: queue[0] == 1 -> | |
| 117 | queue[0] = 0; | |
| 118 | fi; | |
| 119 | if | |
| 120 | :: queue[1] == 1 -> | |
| 121 | queue[1] = 0; | |
| 122 | fi; | |
| d4de4869 MD |
123 | od; |
| 124 | } |