[ac7d5ef0] | 1 | /* |
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| 2 | * Thread Queue Handler |
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| 3 | * |
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| 4 | * |
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| 5 | * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994. |
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| 6 | * On-Line Applications Research Corporation (OAR). |
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| 7 | * All rights assigned to U.S. Government, 1994. |
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| 8 | * |
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| 9 | * This material may be reproduced by or for the U.S. Government pursuant |
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| 10 | * to the copyright license under the clause at DFARS 252.227-7013. This |
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| 11 | * notice must appear in all copies of this file and its derivatives. |
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| 12 | * |
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| 13 | * $Id$ |
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| 14 | */ |
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| 15 | |
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| 16 | #include <rtems/system.h> |
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[5e9b32b] | 17 | #include <rtems/score/chain.h> |
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| 18 | #include <rtems/score/isr.h> |
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| 19 | #include <rtems/score/object.h> |
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| 20 | #include <rtems/score/states.h> |
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| 21 | #include <rtems/score/thread.h> |
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| 22 | #include <rtems/score/threadq.h> |
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| 23 | #include <rtems/score/tqdata.h> |
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[3a4ae6c] | 24 | |
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[ac7d5ef0] | 25 | /*PAGE |
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| 26 | * |
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| 27 | * _Thread_queue_Initialize |
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| 28 | * |
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| 29 | * This routine initializes the specified threadq. |
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| 30 | * |
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| 31 | * Input parameters: |
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[3a4ae6c] | 32 | * the_thread_queue - pointer to a threadq header |
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| 33 | * the_class - class of the object to which this belongs |
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| 34 | * discipline - queueing discipline |
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| 35 | * state - state of waiting threads |
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| 36 | * proxy_extract_callout - MP specific callout |
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| 37 | * timeout_status - return on a timeout |
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[ac7d5ef0] | 38 | * |
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| 39 | * Output parameters: NONE |
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| 40 | */ |
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| 41 | |
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| 42 | void _Thread_queue_Initialize( |
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[7f6a24ab] | 43 | Thread_queue_Control *the_thread_queue, |
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| 44 | Objects_Classes the_class, |
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| 45 | Thread_queue_Disciplines the_discipline, |
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| 46 | States_Control state, |
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[3a4ae6c] | 47 | Thread_queue_Extract_callout proxy_extract_callout, |
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| 48 | unsigned32 timeout_status |
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[ac7d5ef0] | 49 | ) |
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| 50 | { |
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| 51 | unsigned32 index; |
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| 52 | |
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[7f6a24ab] | 53 | _Thread_queue_Extract_table[ the_class ] = proxy_extract_callout; |
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| 54 | |
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[3a4ae6c] | 55 | the_thread_queue->state = state; |
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| 56 | the_thread_queue->discipline = the_discipline; |
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| 57 | the_thread_queue->timeout_status = timeout_status; |
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[107ce47b] | 58 | the_thread_queue->sync_state = THREAD_QUEUE_SYNCHRONIZED; |
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[ac7d5ef0] | 59 | |
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[7f6a24ab] | 60 | switch ( the_discipline ) { |
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| 61 | case THREAD_QUEUE_DISCIPLINE_FIFO: |
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| 62 | _Chain_Initialize_empty( &the_thread_queue->Queues.Fifo ); |
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| 63 | break; |
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| 64 | case THREAD_QUEUE_DISCIPLINE_PRIORITY: |
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| 65 | for( index=0 ; |
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| 66 | index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ; |
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| 67 | index++) |
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| 68 | _Chain_Initialize_empty( &the_thread_queue->Queues.Priority[index] ); |
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| 69 | break; |
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| 70 | } |
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[ac7d5ef0] | 71 | |
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| 72 | } |
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| 73 | |
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| 74 | /*PAGE |
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| 75 | * |
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| 76 | * _Thread_queue_Enqueue |
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| 77 | * |
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| 78 | * This routine blocks a thread, places it on a thread, and optionally |
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| 79 | * starts a timeout timer. |
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| 80 | * |
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| 81 | * Input parameters: |
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| 82 | * the_thread_queue - pointer to threadq |
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| 83 | * timeout - interval to wait |
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| 84 | * |
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| 85 | * Output parameters: NONE |
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| 86 | * |
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| 87 | * INTERRUPT LATENCY: |
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| 88 | * only case |
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| 89 | */ |
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| 90 | |
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| 91 | void _Thread_queue_Enqueue( |
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| 92 | Thread_queue_Control *the_thread_queue, |
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[3a4ae6c] | 93 | Watchdog_Interval timeout |
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[ac7d5ef0] | 94 | ) |
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| 95 | { |
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| 96 | Thread_Control *the_thread; |
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| 97 | |
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| 98 | the_thread = _Thread_Executing; |
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| 99 | |
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[3a4ae6c] | 100 | if ( _Thread_MP_Is_receive( the_thread ) && the_thread->receive_packet ) |
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[ac7d5ef0] | 101 | the_thread = _Thread_MP_Allocate_proxy( the_thread_queue->state ); |
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| 102 | else |
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| 103 | _Thread_Set_state( the_thread, the_thread_queue->state ); |
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| 104 | |
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| 105 | if ( timeout ) { |
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| 106 | _Watchdog_Initialize( |
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| 107 | &the_thread->Timer, |
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| 108 | _Thread_queue_Timeout, |
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| 109 | the_thread->Object.id, |
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| 110 | NULL |
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| 111 | ); |
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| 112 | |
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[8d0b7d96] | 113 | _Watchdog_Insert_ticks( &the_thread->Timer, timeout ); |
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[ac7d5ef0] | 114 | } |
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| 115 | |
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| 116 | switch( the_thread_queue->discipline ) { |
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[7f6a24ab] | 117 | case THREAD_QUEUE_DISCIPLINE_FIFO: |
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[ac7d5ef0] | 118 | _Thread_queue_Enqueue_fifo( the_thread_queue, the_thread, timeout ); |
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| 119 | break; |
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[7f6a24ab] | 120 | case THREAD_QUEUE_DISCIPLINE_PRIORITY: |
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[caaa47c] | 121 | _Thread_queue_Enqueue_priority( the_thread_queue, the_thread, timeout ); |
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[ac7d5ef0] | 122 | break; |
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| 123 | } |
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| 124 | } |
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| 125 | |
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| 126 | /*PAGE |
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| 127 | * |
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| 128 | * _Thread_queue_Dequeue |
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| 129 | * |
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| 130 | * This routine removes a thread from the specified threadq. If the |
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[3a4ae6c] | 131 | * threadq discipline is FIFO, it unblocks a thread, and cancels its |
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[ac7d5ef0] | 132 | * timeout timer. Priority discipline is processed elsewhere. |
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| 133 | * |
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| 134 | * Input parameters: |
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| 135 | * the_thread_queue - pointer to threadq |
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| 136 | * |
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| 137 | * Output parameters: |
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| 138 | * returns - thread dequeued or NULL |
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| 139 | * |
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| 140 | * INTERRUPT LATENCY: |
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| 141 | * check sync |
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| 142 | */ |
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| 143 | |
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| 144 | Thread_Control *_Thread_queue_Dequeue( |
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| 145 | Thread_queue_Control *the_thread_queue |
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| 146 | ) |
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| 147 | { |
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| 148 | Thread_Control *the_thread; |
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| 149 | |
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| 150 | switch ( the_thread_queue->discipline ) { |
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[7f6a24ab] | 151 | case THREAD_QUEUE_DISCIPLINE_FIFO: |
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[ac7d5ef0] | 152 | the_thread = _Thread_queue_Dequeue_fifo( the_thread_queue ); |
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| 153 | break; |
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[7f6a24ab] | 154 | case THREAD_QUEUE_DISCIPLINE_PRIORITY: |
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[ac7d5ef0] | 155 | the_thread = _Thread_queue_Dequeue_priority( the_thread_queue ); |
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| 156 | break; |
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| 157 | default: /* this is only to prevent warnings */ |
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| 158 | the_thread = NULL; |
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| 159 | break; |
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| 160 | } |
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| 161 | |
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[caaa47c] | 162 | return( the_thread ); |
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[ac7d5ef0] | 163 | } |
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| 164 | |
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[7f6a24ab] | 165 | /*PAGE |
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| 166 | * |
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| 167 | * _Thread_queue_Extract_with_proxy |
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| 168 | * |
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| 169 | * This routine extracts the_thread from the_thread_queue |
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| 170 | * and insures that if there is a proxy for this task on |
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| 171 | * another node, it is also dealt with. |
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| 172 | * |
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| 173 | * XXX |
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| 174 | */ |
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| 175 | |
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| 176 | boolean _Thread_queue_Extract_with_proxy( |
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| 177 | Thread_Control *the_thread |
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| 178 | ) |
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| 179 | { |
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| 180 | States_Control state; |
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| 181 | Objects_Classes the_class; |
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| 182 | Thread_queue_Extract_callout proxy_extract_callout; |
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| 183 | |
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| 184 | state = the_thread->current_state; |
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| 185 | |
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| 186 | if ( _States_Is_waiting_on_thread_queue( state ) ) { |
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| 187 | if ( _States_Is_waiting_for_rpc_reply( state ) && |
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| 188 | _States_Is_locally_blocked( state ) ) { |
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| 189 | |
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[3a4ae6c] | 190 | the_class = _Objects_Get_class( the_thread->Wait.id ); |
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[7f6a24ab] | 191 | |
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| 192 | proxy_extract_callout = _Thread_queue_Extract_table[ the_class ]; |
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| 193 | |
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| 194 | if ( proxy_extract_callout ) |
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| 195 | (*proxy_extract_callout)( the_thread ); |
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| 196 | } |
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| 197 | _Thread_queue_Extract( the_thread->Wait.queue, the_thread ); |
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| 198 | |
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| 199 | return TRUE; |
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| 200 | } |
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| 201 | return FALSE; |
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| 202 | } |
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| 203 | |
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[ac7d5ef0] | 204 | /*PAGE |
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| 205 | * |
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| 206 | * _Thread_queue_Extract |
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| 207 | * |
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| 208 | * This routine removes a specific thread from the specified threadq, |
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| 209 | * deletes any timeout, and unblocks the thread. |
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| 210 | * |
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| 211 | * Input parameters: |
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| 212 | * the_thread_queue - pointer to a threadq header |
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| 213 | * the_thread - pointer to a thread control block |
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| 214 | * |
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| 215 | * Output parameters: NONE |
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| 216 | * |
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| 217 | * INTERRUPT LATENCY: NONE |
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| 218 | */ |
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| 219 | |
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| 220 | void _Thread_queue_Extract( |
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| 221 | Thread_queue_Control *the_thread_queue, |
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| 222 | Thread_Control *the_thread |
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| 223 | ) |
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| 224 | { |
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| 225 | switch ( the_thread_queue->discipline ) { |
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[7f6a24ab] | 226 | case THREAD_QUEUE_DISCIPLINE_FIFO: |
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[ac7d5ef0] | 227 | _Thread_queue_Extract_fifo( the_thread_queue, the_thread ); |
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| 228 | break; |
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[7f6a24ab] | 229 | case THREAD_QUEUE_DISCIPLINE_PRIORITY: |
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[ac7d5ef0] | 230 | _Thread_queue_Extract_priority( the_thread_queue, the_thread ); |
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| 231 | break; |
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| 232 | } |
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| 233 | } |
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| 234 | |
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| 235 | /*PAGE |
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| 236 | * |
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| 237 | * _Thread_queue_Flush |
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| 238 | * |
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| 239 | * This kernel routine flushes the given thread queue. |
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| 240 | * |
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| 241 | * Input parameters: |
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[3a4ae6c] | 242 | * the_thread_queue - pointer to threadq to be flushed |
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| 243 | * remote_extract_callout - pointer to routine which extracts a remote thread |
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| 244 | * status - status to return to the thread |
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[ac7d5ef0] | 245 | * |
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| 246 | * Output parameters: NONE |
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| 247 | */ |
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| 248 | |
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| 249 | void _Thread_queue_Flush( |
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| 250 | Thread_queue_Control *the_thread_queue, |
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[3a4ae6c] | 251 | Thread_queue_Flush_callout remote_extract_callout, |
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| 252 | unsigned32 status |
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[ac7d5ef0] | 253 | ) |
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| 254 | { |
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| 255 | Thread_Control *the_thread; |
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| 256 | |
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| 257 | while ( (the_thread = _Thread_queue_Dequeue( the_thread_queue )) ) { |
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| 258 | if ( _Objects_Is_local_id( the_thread->Object.id ) ) |
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[3a4ae6c] | 259 | the_thread->Wait.return_code = status; |
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[ac7d5ef0] | 260 | else |
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| 261 | ( *remote_extract_callout )( the_thread ); |
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| 262 | } |
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| 263 | } |
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| 264 | |
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| 265 | /*PAGE |
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| 266 | * |
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| 267 | * _Thread_queue_First |
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| 268 | * |
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| 269 | * This routines returns a pointer to the first thread on the |
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| 270 | * specified threadq. |
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| 271 | * |
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| 272 | * Input parameters: |
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| 273 | * the_thread_queue - pointer to thread queue |
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| 274 | * |
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| 275 | * Output parameters: |
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| 276 | * returns - first thread or NULL |
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| 277 | */ |
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| 278 | |
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| 279 | Thread_Control *_Thread_queue_First( |
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| 280 | Thread_queue_Control *the_thread_queue |
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| 281 | ) |
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| 282 | { |
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| 283 | Thread_Control *the_thread; |
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| 284 | |
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| 285 | switch ( the_thread_queue->discipline ) { |
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[7f6a24ab] | 286 | case THREAD_QUEUE_DISCIPLINE_FIFO: |
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[ac7d5ef0] | 287 | the_thread = _Thread_queue_First_fifo( the_thread_queue ); |
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| 288 | break; |
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[7f6a24ab] | 289 | case THREAD_QUEUE_DISCIPLINE_PRIORITY: |
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[ac7d5ef0] | 290 | the_thread = _Thread_queue_First_priority( the_thread_queue ); |
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| 291 | break; |
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| 292 | default: /* this is only to prevent warnings */ |
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| 293 | the_thread = NULL; |
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| 294 | break; |
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| 295 | } |
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| 296 | |
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| 297 | return the_thread; |
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| 298 | } |
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| 299 | |
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| 300 | /*PAGE |
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| 301 | * |
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| 302 | * _Thread_queue_Timeout |
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| 303 | * |
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| 304 | * This routine processes a thread which timeouts while waiting on |
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| 305 | * a thread queue. It is called by the watchdog handler. |
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| 306 | * |
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| 307 | * Input parameters: |
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| 308 | * id - thread id |
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| 309 | * |
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| 310 | * Output parameters: NONE |
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| 311 | */ |
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| 312 | |
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| 313 | void _Thread_queue_Timeout( |
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| 314 | Objects_Id id, |
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| 315 | void *ignored |
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| 316 | ) |
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| 317 | { |
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[caaa47c] | 318 | Thread_Control *the_thread; |
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| 319 | Thread_queue_Control *the_thread_queue; |
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| 320 | Objects_Locations location; |
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[ac7d5ef0] | 321 | |
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| 322 | the_thread = _Thread_Get( id, &location ); |
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| 323 | switch ( location ) { |
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| 324 | case OBJECTS_ERROR: |
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| 325 | case OBJECTS_REMOTE: /* impossible */ |
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| 326 | break; |
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| 327 | case OBJECTS_LOCAL: |
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[caaa47c] | 328 | the_thread_queue = the_thread->Wait.queue; |
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| 329 | |
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[107ce47b] | 330 | if ( the_thread_queue->sync_state != THREAD_QUEUE_SYNCHRONIZED && |
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| 331 | _Thread_Is_executing( the_thread ) ) { |
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[caaa47c] | 332 | if ( the_thread_queue->sync_state != THREAD_QUEUE_SATISFIED ) |
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| 333 | the_thread_queue->sync_state = THREAD_QUEUE_TIMEOUT; |
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| 334 | } else { |
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| 335 | the_thread->Wait.return_code = the_thread->Wait.queue->timeout_status; |
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| 336 | _Thread_queue_Extract( the_thread->Wait.queue, the_thread ); |
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| 337 | } |
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[ac7d5ef0] | 338 | _Thread_Unnest_dispatch(); |
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| 339 | break; |
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| 340 | } |
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| 341 | } |
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| 342 | |
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| 343 | /*PAGE |
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| 344 | * |
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| 345 | * _Thread_queue_Enqueue_fifo |
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| 346 | * |
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| 347 | * This routine blocks a thread, places it on a thread, and optionally |
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| 348 | * starts a timeout timer. |
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| 349 | * |
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| 350 | * Input parameters: |
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| 351 | * the_thread_queue - pointer to threadq |
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| 352 | * the_thread - pointer to the thread to block |
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| 353 | * timeout - interval to wait |
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| 354 | * |
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| 355 | * Output parameters: NONE |
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| 356 | * |
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| 357 | * INTERRUPT LATENCY: |
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| 358 | * only case |
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| 359 | */ |
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| 360 | |
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| 361 | void _Thread_queue_Enqueue_fifo ( |
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| 362 | Thread_queue_Control *the_thread_queue, |
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| 363 | Thread_Control *the_thread, |
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[3a4ae6c] | 364 | Watchdog_Interval timeout |
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[ac7d5ef0] | 365 | ) |
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| 366 | { |
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[107ce47b] | 367 | ISR_Level level; |
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| 368 | Thread_queue_States sync_state; |
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[ac7d5ef0] | 369 | |
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| 370 | _ISR_Disable( level ); |
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| 371 | |
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[107ce47b] | 372 | sync_state = the_thread_queue->sync_state; |
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| 373 | the_thread_queue->sync_state = THREAD_QUEUE_SYNCHRONIZED; |
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| 374 | |
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| 375 | switch ( sync_state ) { |
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| 376 | case THREAD_QUEUE_SYNCHRONIZED: |
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| 377 | /* |
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| 378 | * This should never happen. It indicates that someone did not |
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| 379 | * enter a thread queue critical section. |
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| 380 | */ |
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| 381 | break; |
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[f00a0522] | 382 | |
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[caaa47c] | 383 | case THREAD_QUEUE_NOTHING_HAPPENED: |
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| 384 | _Chain_Append_unprotected( |
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| 385 | &the_thread_queue->Queues.Fifo, |
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| 386 | &the_thread->Object.Node |
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| 387 | ); |
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| 388 | _ISR_Enable( level ); |
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| 389 | return; |
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[ac7d5ef0] | 390 | |
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[caaa47c] | 391 | case THREAD_QUEUE_TIMEOUT: |
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| 392 | the_thread->Wait.return_code = the_thread->Wait.queue->timeout_status; |
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| 393 | _ISR_Enable( level ); |
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| 394 | break; |
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[ac7d5ef0] | 395 | |
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[caaa47c] | 396 | case THREAD_QUEUE_SATISFIED: |
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| 397 | if ( _Watchdog_Is_active( &the_thread->Timer ) ) { |
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| 398 | _Watchdog_Deactivate( &the_thread->Timer ); |
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| 399 | _ISR_Enable( level ); |
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| 400 | (void) _Watchdog_Remove( &the_thread->Timer ); |
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| 401 | } else |
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| 402 | _ISR_Enable( level ); |
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| 403 | break; |
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[ac7d5ef0] | 404 | } |
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| 405 | |
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[caaa47c] | 406 | /* |
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| 407 | * Global objects with thread queue's should not be operated on from an |
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| 408 | * ISR. But the sync code still must allow short timeouts to be processed |
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| 409 | * correctly. |
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| 410 | */ |
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| 411 | |
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| 412 | _Thread_Unblock( the_thread ); |
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[ac7d5ef0] | 413 | |
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| 414 | if ( !_Objects_Is_local_id( the_thread->Object.id ) ) |
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| 415 | _Thread_MP_Free_proxy( the_thread ); |
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| 416 | |
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| 417 | } |
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| 418 | |
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| 419 | /*PAGE |
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| 420 | * |
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| 421 | * _Thread_queue_Dequeue_fifo |
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| 422 | * |
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| 423 | * This routine removes a thread from the specified threadq. |
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| 424 | * |
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| 425 | * Input parameters: |
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| 426 | * the_thread_queue - pointer to threadq |
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| 427 | * |
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| 428 | * Output parameters: |
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| 429 | * returns - thread dequeued or NULL |
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| 430 | * |
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| 431 | * INTERRUPT LATENCY: |
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| 432 | * check sync |
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[3a4ae6c] | 433 | * FIFO |
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[ac7d5ef0] | 434 | */ |
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| 435 | |
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| 436 | Thread_Control *_Thread_queue_Dequeue_fifo( |
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| 437 | Thread_queue_Control *the_thread_queue |
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| 438 | ) |
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| 439 | { |
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| 440 | ISR_Level level; |
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| 441 | Thread_Control *the_thread; |
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| 442 | |
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| 443 | _ISR_Disable( level ); |
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| 444 | if ( !_Chain_Is_empty( &the_thread_queue->Queues.Fifo ) ) { |
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| 445 | |
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| 446 | the_thread = (Thread_Control *) |
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| 447 | _Chain_Get_first_unprotected( &the_thread_queue->Queues.Fifo ); |
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| 448 | |
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| 449 | if ( !_Watchdog_Is_active( &the_thread->Timer ) ) { |
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| 450 | _ISR_Enable( level ); |
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| 451 | _Thread_Unblock( the_thread ); |
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| 452 | } else { |
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| 453 | _Watchdog_Deactivate( &the_thread->Timer ); |
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| 454 | _ISR_Enable( level ); |
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| 455 | (void) _Watchdog_Remove( &the_thread->Timer ); |
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| 456 | _Thread_Unblock( the_thread ); |
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| 457 | } |
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| 458 | |
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| 459 | if ( !_Objects_Is_local_id( the_thread->Object.id ) ) |
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| 460 | _Thread_MP_Free_proxy( the_thread ); |
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| 461 | |
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[caaa47c] | 462 | return the_thread; |
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[107ce47b] | 463 | } |
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| 464 | |
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| 465 | switch ( the_thread_queue->sync_state ) { |
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| 466 | case THREAD_QUEUE_SYNCHRONIZED: |
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| 467 | case THREAD_QUEUE_SATISFIED: |
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| 468 | _ISR_Enable( level ); |
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| 469 | return NULL; |
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| 470 | |
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| 471 | case THREAD_QUEUE_NOTHING_HAPPENED: |
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| 472 | case THREAD_QUEUE_TIMEOUT: |
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| 473 | the_thread_queue->sync_state = THREAD_QUEUE_SATISFIED; |
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| 474 | _ISR_Enable( level ); |
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| 475 | return _Thread_Executing; |
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[ac7d5ef0] | 476 | } |
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[107ce47b] | 477 | return NULL; /* this is only to prevent warnings */ |
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[ac7d5ef0] | 478 | } |
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| 479 | |
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| 480 | /*PAGE |
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| 481 | * |
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| 482 | * _Thread_queue_Extract_fifo |
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| 483 | * |
---|
| 484 | * This routine removes a specific thread from the specified threadq, |
---|
| 485 | * deletes any timeout, and unblocks the thread. |
---|
| 486 | * |
---|
| 487 | * Input parameters: |
---|
| 488 | * the_thread_queue - pointer to a threadq header |
---|
| 489 | * the_thread - pointer to the thread to block |
---|
| 490 | * |
---|
| 491 | * Output parameters: NONE |
---|
| 492 | * |
---|
| 493 | * INTERRUPT LATENCY: |
---|
| 494 | * EXTRACT_FIFO |
---|
| 495 | */ |
---|
| 496 | |
---|
| 497 | void _Thread_queue_Extract_fifo( |
---|
| 498 | Thread_queue_Control *the_thread_queue, |
---|
| 499 | Thread_Control *the_thread |
---|
| 500 | ) |
---|
| 501 | { |
---|
| 502 | ISR_Level level; |
---|
| 503 | |
---|
| 504 | _ISR_Disable( level ); |
---|
| 505 | |
---|
| 506 | if ( !_States_Is_waiting_on_thread_queue( the_thread->current_state ) ) { |
---|
| 507 | _ISR_Enable( level ); |
---|
| 508 | return; |
---|
| 509 | } |
---|
| 510 | |
---|
| 511 | _Chain_Extract_unprotected( &the_thread->Object.Node ); |
---|
| 512 | |
---|
| 513 | if ( !_Watchdog_Is_active( &the_thread->Timer ) ) { |
---|
| 514 | _ISR_Enable( level ); |
---|
| 515 | } else { |
---|
| 516 | _Watchdog_Deactivate( &the_thread->Timer ); |
---|
| 517 | _ISR_Enable( level ); |
---|
| 518 | (void) _Watchdog_Remove( &the_thread->Timer ); |
---|
| 519 | } |
---|
| 520 | |
---|
[7f6a24ab] | 521 | _Thread_Unblock( the_thread ); |
---|
| 522 | |
---|
[ac7d5ef0] | 523 | if ( !_Objects_Is_local_id( the_thread->Object.id ) ) |
---|
| 524 | _Thread_MP_Free_proxy( the_thread ); |
---|
[7f6a24ab] | 525 | |
---|
[ac7d5ef0] | 526 | } |
---|
| 527 | |
---|
| 528 | /*PAGE |
---|
| 529 | * |
---|
| 530 | * _Thread_queue_First_fifo |
---|
| 531 | * |
---|
| 532 | * This routines returns a pointer to the first thread on the |
---|
| 533 | * specified threadq. |
---|
| 534 | * |
---|
| 535 | * Input parameters: |
---|
| 536 | * the_thread_queue - pointer to threadq |
---|
| 537 | * |
---|
| 538 | * Output parameters: |
---|
| 539 | * returns - first thread or NULL |
---|
| 540 | */ |
---|
| 541 | |
---|
| 542 | Thread_Control *_Thread_queue_First_fifo( |
---|
| 543 | Thread_queue_Control *the_thread_queue |
---|
| 544 | ) |
---|
| 545 | { |
---|
| 546 | if ( !_Chain_Is_empty( &the_thread_queue->Queues.Fifo ) ) |
---|
| 547 | return (Thread_Control *) the_thread_queue->Queues.Fifo.first; |
---|
| 548 | |
---|
| 549 | return NULL; |
---|
| 550 | } |
---|
| 551 | |
---|
| 552 | /*PAGE |
---|
| 553 | * |
---|
| 554 | * _Thread_queue_Enqueue_priority |
---|
| 555 | * |
---|
| 556 | * This routine blocks a thread, places it on a thread, and optionally |
---|
| 557 | * starts a timeout timer. |
---|
| 558 | * |
---|
| 559 | * Input parameters: |
---|
| 560 | * the_thread_queue - pointer to threadq |
---|
| 561 | * thread - thread to insert |
---|
| 562 | * timeout - timeout interval in ticks |
---|
| 563 | * |
---|
| 564 | * Output parameters: NONE |
---|
| 565 | * |
---|
| 566 | * INTERRUPT LATENCY: |
---|
| 567 | * forward less than |
---|
| 568 | * forward equal |
---|
| 569 | */ |
---|
| 570 | |
---|
| 571 | void _Thread_queue_Enqueue_priority( |
---|
| 572 | Thread_queue_Control *the_thread_queue, |
---|
| 573 | Thread_Control *the_thread, |
---|
[3a4ae6c] | 574 | Watchdog_Interval timeout |
---|
[ac7d5ef0] | 575 | ) |
---|
| 576 | { |
---|
[107ce47b] | 577 | Priority_Control search_priority; |
---|
| 578 | Thread_Control *search_thread; |
---|
| 579 | ISR_Level level; |
---|
| 580 | Chain_Control *header; |
---|
| 581 | unsigned32 header_index; |
---|
| 582 | Chain_Node *the_node; |
---|
| 583 | Chain_Node *next_node; |
---|
| 584 | Chain_Node *previous_node; |
---|
| 585 | Chain_Node *search_node; |
---|
| 586 | Priority_Control priority; |
---|
| 587 | States_Control block_state; |
---|
| 588 | Thread_queue_States sync_state; |
---|
[ac7d5ef0] | 589 | |
---|
| 590 | _Chain_Initialize_empty( &the_thread->Wait.Block2n ); |
---|
| 591 | |
---|
| 592 | priority = the_thread->current_priority; |
---|
| 593 | header_index = _Thread_queue_Header_number( priority ); |
---|
| 594 | header = &the_thread_queue->Queues.Priority[ header_index ]; |
---|
| 595 | block_state = the_thread_queue->state; |
---|
| 596 | |
---|
| 597 | if ( _Thread_queue_Is_reverse_search( priority ) ) |
---|
| 598 | goto restart_reverse_search; |
---|
| 599 | |
---|
| 600 | restart_forward_search: |
---|
[3a4ae6c] | 601 | search_priority = PRIORITY_MINIMUM - 1; |
---|
[ac7d5ef0] | 602 | _ISR_Disable( level ); |
---|
| 603 | search_thread = (Thread_Control *) header->first; |
---|
| 604 | while ( !_Chain_Is_tail( header, (Chain_Node *)search_thread ) ) { |
---|
| 605 | search_priority = search_thread->current_priority; |
---|
| 606 | if ( priority <= search_priority ) |
---|
| 607 | break; |
---|
| 608 | |
---|
| 609 | #if ( CPU_UNROLL_ENQUEUE_PRIORITY == TRUE ) |
---|
| 610 | search_thread = (Thread_Control *) search_thread->Object.Node.next; |
---|
| 611 | if ( _Chain_Is_tail( header, (Chain_Node *)search_thread ) ) |
---|
| 612 | break; |
---|
| 613 | search_priority = search_thread->current_priority; |
---|
| 614 | if ( priority <= search_priority ) |
---|
| 615 | break; |
---|
| 616 | #endif |
---|
| 617 | _ISR_Flash( level ); |
---|
| 618 | if ( !_States_Are_set( search_thread->current_state, block_state) ) { |
---|
| 619 | _ISR_Enable( level ); |
---|
| 620 | goto restart_forward_search; |
---|
| 621 | } |
---|
| 622 | search_thread = |
---|
| 623 | (Thread_Control *)search_thread->Object.Node.next; |
---|
| 624 | } |
---|
| 625 | |
---|
[f00a0522] | 626 | if ( the_thread_queue->sync_state != THREAD_QUEUE_NOTHING_HAPPENED ) |
---|
[107ce47b] | 627 | goto synchronize; |
---|
| 628 | |
---|
| 629 | the_thread_queue->sync_state = THREAD_QUEUE_SYNCHRONIZED; |
---|
[f00a0522] | 630 | |
---|
[ac7d5ef0] | 631 | if ( priority == search_priority ) |
---|
| 632 | goto equal_priority; |
---|
| 633 | |
---|
| 634 | search_node = (Chain_Node *) search_thread; |
---|
| 635 | previous_node = search_node->previous; |
---|
| 636 | the_node = (Chain_Node *) the_thread; |
---|
| 637 | |
---|
| 638 | the_node->next = search_node; |
---|
| 639 | the_node->previous = previous_node; |
---|
| 640 | previous_node->next = the_node; |
---|
| 641 | search_node->previous = the_node; |
---|
| 642 | _ISR_Enable( level ); |
---|
| 643 | return; |
---|
| 644 | |
---|
| 645 | restart_reverse_search: |
---|
[3a4ae6c] | 646 | search_priority = PRIORITY_MAXIMUM + 1; |
---|
[ac7d5ef0] | 647 | |
---|
| 648 | _ISR_Disable( level ); |
---|
| 649 | search_thread = (Thread_Control *) header->last; |
---|
| 650 | while ( !_Chain_Is_head( header, (Chain_Node *)search_thread ) ) { |
---|
| 651 | search_priority = search_thread->current_priority; |
---|
| 652 | if ( priority >= search_priority ) |
---|
| 653 | break; |
---|
| 654 | #if ( CPU_UNROLL_ENQUEUE_PRIORITY == TRUE ) |
---|
| 655 | search_thread = (Thread_Control *) search_thread->Object.Node.previous; |
---|
| 656 | if ( _Chain_Is_head( header, (Chain_Node *)search_thread ) ) |
---|
| 657 | break; |
---|
| 658 | search_priority = search_thread->current_priority; |
---|
| 659 | if ( priority >= search_priority ) |
---|
| 660 | break; |
---|
| 661 | #endif |
---|
| 662 | _ISR_Flash( level ); |
---|
| 663 | if ( !_States_Are_set( search_thread->current_state, block_state) ) { |
---|
| 664 | _ISR_Enable( level ); |
---|
| 665 | goto restart_reverse_search; |
---|
| 666 | } |
---|
| 667 | search_thread = (Thread_Control *) |
---|
| 668 | search_thread->Object.Node.previous; |
---|
| 669 | } |
---|
| 670 | |
---|
[f00a0522] | 671 | if ( the_thread_queue->sync_state != THREAD_QUEUE_NOTHING_HAPPENED ) |
---|
[107ce47b] | 672 | goto synchronize; |
---|
| 673 | |
---|
| 674 | the_thread_queue->sync_state = THREAD_QUEUE_SYNCHRONIZED; |
---|
[f00a0522] | 675 | |
---|
[ac7d5ef0] | 676 | if ( priority == search_priority ) |
---|
| 677 | goto equal_priority; |
---|
| 678 | |
---|
| 679 | search_node = (Chain_Node *) search_thread; |
---|
| 680 | next_node = search_node->next; |
---|
| 681 | the_node = (Chain_Node *) the_thread; |
---|
| 682 | |
---|
| 683 | the_node->next = next_node; |
---|
| 684 | the_node->previous = search_node; |
---|
| 685 | search_node->next = the_node; |
---|
| 686 | next_node->previous = the_node; |
---|
| 687 | _ISR_Enable( level ); |
---|
| 688 | return; |
---|
| 689 | |
---|
| 690 | equal_priority: /* add at end of priority group */ |
---|
| 691 | search_node = _Chain_Tail( &search_thread->Wait.Block2n ); |
---|
| 692 | previous_node = search_node->previous; |
---|
| 693 | the_node = (Chain_Node *) the_thread; |
---|
| 694 | |
---|
| 695 | the_node->next = search_node; |
---|
| 696 | the_node->previous = previous_node; |
---|
| 697 | previous_node->next = the_node; |
---|
| 698 | search_node->previous = the_node; |
---|
| 699 | _ISR_Enable( level ); |
---|
| 700 | return; |
---|
| 701 | |
---|
[107ce47b] | 702 | synchronize: |
---|
[caaa47c] | 703 | |
---|
[107ce47b] | 704 | sync_state = the_thread_queue->sync_state; |
---|
| 705 | the_thread_queue->sync_state = THREAD_QUEUE_SYNCHRONIZED; |
---|
| 706 | |
---|
| 707 | switch ( sync_state ) { |
---|
| 708 | case THREAD_QUEUE_SYNCHRONIZED: |
---|
| 709 | /* |
---|
| 710 | * This should never happen. It indicates that someone did not |
---|
| 711 | * enter a thread queue critical section. |
---|
| 712 | */ |
---|
| 713 | break; |
---|
| 714 | |
---|
[caaa47c] | 715 | case THREAD_QUEUE_NOTHING_HAPPENED: |
---|
| 716 | /* |
---|
| 717 | * All of this was dealt with above. This should never happen. |
---|
| 718 | */ |
---|
| 719 | break; |
---|
| 720 | |
---|
| 721 | case THREAD_QUEUE_TIMEOUT: |
---|
| 722 | the_thread->Wait.return_code = the_thread->Wait.queue->timeout_status; |
---|
| 723 | _ISR_Enable( level ); |
---|
| 724 | break; |
---|
| 725 | |
---|
| 726 | case THREAD_QUEUE_SATISFIED: |
---|
| 727 | if ( _Watchdog_Is_active( &the_thread->Timer ) ) { |
---|
| 728 | _Watchdog_Deactivate( &the_thread->Timer ); |
---|
| 729 | _ISR_Enable( level ); |
---|
| 730 | (void) _Watchdog_Remove( &the_thread->Timer ); |
---|
| 731 | } else |
---|
| 732 | _ISR_Enable( level ); |
---|
| 733 | break; |
---|
[ac7d5ef0] | 734 | } |
---|
[caaa47c] | 735 | |
---|
| 736 | /* |
---|
| 737 | * Global objects with thread queue's should not be operated on from an |
---|
| 738 | * ISR. But the sync code still must allow short timeouts to be processed |
---|
| 739 | * correctly. |
---|
| 740 | */ |
---|
| 741 | |
---|
| 742 | _Thread_Unblock( the_thread ); |
---|
| 743 | |
---|
[ac7d5ef0] | 744 | if ( !_Objects_Is_local_id( the_thread->Object.id ) ) |
---|
| 745 | _Thread_MP_Free_proxy( the_thread ); |
---|
| 746 | } |
---|
| 747 | |
---|
| 748 | /*PAGE |
---|
| 749 | * |
---|
| 750 | * _Thread_queue_Dequeue_priority |
---|
| 751 | * |
---|
[3a4ae6c] | 752 | * This routine removes a thread from the specified PRIORITY based |
---|
[ac7d5ef0] | 753 | * threadq, unblocks it, and cancels its timeout timer. |
---|
| 754 | * |
---|
| 755 | * Input parameters: |
---|
| 756 | * the_thread_queue - pointer to thread queue |
---|
| 757 | * |
---|
| 758 | * Output parameters: |
---|
| 759 | * returns - thread dequeued or NULL |
---|
| 760 | * |
---|
| 761 | * INTERRUPT LATENCY: |
---|
| 762 | * only case |
---|
| 763 | */ |
---|
| 764 | |
---|
| 765 | Thread_Control *_Thread_queue_Dequeue_priority( |
---|
| 766 | Thread_queue_Control *the_thread_queue |
---|
| 767 | ) |
---|
| 768 | { |
---|
[107ce47b] | 769 | unsigned32 index; |
---|
| 770 | ISR_Level level; |
---|
| 771 | Thread_Control *the_thread = NULL; /* just to remove warnings */ |
---|
[ac7d5ef0] | 772 | Thread_Control *new_first_thread; |
---|
| 773 | Chain_Node *new_first_node; |
---|
| 774 | Chain_Node *new_second_node; |
---|
| 775 | Chain_Node *last_node; |
---|
| 776 | Chain_Node *next_node; |
---|
| 777 | Chain_Node *previous_node; |
---|
| 778 | |
---|
[caaa47c] | 779 | _ISR_Disable( level ); |
---|
[ac7d5ef0] | 780 | for( index=0 ; |
---|
| 781 | index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ; |
---|
| 782 | index++ ) { |
---|
| 783 | if ( !_Chain_Is_empty( &the_thread_queue->Queues.Priority[ index ] ) ) { |
---|
| 784 | the_thread = (Thread_Control *) |
---|
| 785 | the_thread_queue->Queues.Priority[ index ].first; |
---|
| 786 | goto dequeue; |
---|
| 787 | } |
---|
| 788 | } |
---|
[caaa47c] | 789 | |
---|
[107ce47b] | 790 | switch ( the_thread_queue->sync_state ) { |
---|
| 791 | case THREAD_QUEUE_SYNCHRONIZED: |
---|
| 792 | case THREAD_QUEUE_SATISFIED: |
---|
| 793 | _ISR_Enable( level ); |
---|
| 794 | return NULL; |
---|
[caaa47c] | 795 | |
---|
[107ce47b] | 796 | case THREAD_QUEUE_NOTHING_HAPPENED: |
---|
| 797 | case THREAD_QUEUE_TIMEOUT: |
---|
| 798 | the_thread_queue->sync_state = THREAD_QUEUE_SATISFIED; |
---|
| 799 | _ISR_Enable( level ); |
---|
| 800 | return _Thread_Executing; |
---|
| 801 | } |
---|
[ac7d5ef0] | 802 | |
---|
| 803 | dequeue: |
---|
| 804 | new_first_node = the_thread->Wait.Block2n.first; |
---|
| 805 | new_first_thread = (Thread_Control *) new_first_node; |
---|
| 806 | next_node = the_thread->Object.Node.next; |
---|
| 807 | previous_node = the_thread->Object.Node.previous; |
---|
| 808 | |
---|
| 809 | if ( !_Chain_Is_empty( &the_thread->Wait.Block2n ) ) { |
---|
| 810 | last_node = the_thread->Wait.Block2n.last; |
---|
| 811 | new_second_node = new_first_node->next; |
---|
| 812 | |
---|
| 813 | previous_node->next = new_first_node; |
---|
| 814 | next_node->previous = new_first_node; |
---|
| 815 | new_first_node->next = next_node; |
---|
| 816 | new_first_node->previous = previous_node; |
---|
| 817 | |
---|
| 818 | if ( !_Chain_Has_only_one_node( &the_thread->Wait.Block2n ) ) { |
---|
| 819 | /* > two threads on 2-n */ |
---|
| 820 | new_second_node->previous = |
---|
| 821 | _Chain_Head( &new_first_thread->Wait.Block2n ); |
---|
| 822 | |
---|
| 823 | new_first_thread->Wait.Block2n.first = new_second_node; |
---|
| 824 | new_first_thread->Wait.Block2n.last = last_node; |
---|
| 825 | |
---|
| 826 | last_node->next = _Chain_Tail( &new_first_thread->Wait.Block2n ); |
---|
| 827 | } |
---|
| 828 | } else { |
---|
| 829 | previous_node->next = next_node; |
---|
| 830 | next_node->previous = previous_node; |
---|
| 831 | } |
---|
| 832 | |
---|
| 833 | if ( !_Watchdog_Is_active( &the_thread->Timer ) ) { |
---|
| 834 | _ISR_Enable( level ); |
---|
| 835 | _Thread_Unblock( the_thread ); |
---|
| 836 | } else { |
---|
| 837 | _Watchdog_Deactivate( &the_thread->Timer ); |
---|
| 838 | _ISR_Enable( level ); |
---|
| 839 | (void) _Watchdog_Remove( &the_thread->Timer ); |
---|
| 840 | _Thread_Unblock( the_thread ); |
---|
| 841 | } |
---|
| 842 | |
---|
| 843 | if ( !_Objects_Is_local_id( the_thread->Object.id ) ) |
---|
| 844 | _Thread_MP_Free_proxy( the_thread ); |
---|
| 845 | return( the_thread ); |
---|
| 846 | } |
---|
| 847 | |
---|
| 848 | /*PAGE |
---|
| 849 | * |
---|
| 850 | * _Thread_queue_Extract_priority |
---|
| 851 | * |
---|
| 852 | * This routine removes a specific thread from the specified threadq, |
---|
| 853 | * deletes any timeout, and unblocks the thread. |
---|
| 854 | * |
---|
| 855 | * Input parameters: |
---|
| 856 | * the_thread_queue - pointer to a threadq header |
---|
| 857 | * the_thread - pointer to a thread control block |
---|
| 858 | * |
---|
| 859 | * Output parameters: NONE |
---|
| 860 | * |
---|
| 861 | * INTERRUPT LATENCY: |
---|
| 862 | * EXTRACT_PRIORITY |
---|
| 863 | */ |
---|
| 864 | |
---|
| 865 | void _Thread_queue_Extract_priority( |
---|
| 866 | Thread_queue_Control *the_thread_queue, |
---|
| 867 | Thread_Control *the_thread |
---|
| 868 | ) |
---|
| 869 | { |
---|
| 870 | ISR_Level level; |
---|
| 871 | Chain_Node *the_node; |
---|
| 872 | Chain_Node *next_node; |
---|
| 873 | Chain_Node *previous_node; |
---|
| 874 | Thread_Control *new_first_thread; |
---|
| 875 | Chain_Node *new_first_node; |
---|
| 876 | Chain_Node *new_second_node; |
---|
| 877 | Chain_Node *last_node; |
---|
| 878 | |
---|
| 879 | the_node = (Chain_Node *) the_thread; |
---|
| 880 | _ISR_Disable( level ); |
---|
| 881 | if ( _States_Is_waiting_on_thread_queue( the_thread->current_state ) ) { |
---|
| 882 | next_node = the_node->next; |
---|
| 883 | previous_node = the_node->previous; |
---|
| 884 | |
---|
| 885 | if ( !_Chain_Is_empty( &the_thread->Wait.Block2n ) ) { |
---|
| 886 | new_first_node = the_thread->Wait.Block2n.first; |
---|
| 887 | new_first_thread = (Thread_Control *) new_first_node; |
---|
| 888 | last_node = the_thread->Wait.Block2n.last; |
---|
| 889 | new_second_node = new_first_node->next; |
---|
| 890 | |
---|
| 891 | previous_node->next = new_first_node; |
---|
| 892 | next_node->previous = new_first_node; |
---|
| 893 | new_first_node->next = next_node; |
---|
| 894 | new_first_node->previous = previous_node; |
---|
| 895 | |
---|
| 896 | if ( !_Chain_Has_only_one_node( &the_thread->Wait.Block2n ) ) { |
---|
| 897 | /* > two threads on 2-n */ |
---|
| 898 | new_second_node->previous = |
---|
| 899 | _Chain_Head( &new_first_thread->Wait.Block2n ); |
---|
| 900 | new_first_thread->Wait.Block2n.first = new_second_node; |
---|
| 901 | |
---|
| 902 | new_first_thread->Wait.Block2n.last = last_node; |
---|
| 903 | last_node->next = _Chain_Tail( &new_first_thread->Wait.Block2n ); |
---|
| 904 | } |
---|
| 905 | } else { |
---|
| 906 | previous_node->next = next_node; |
---|
| 907 | next_node->previous = previous_node; |
---|
| 908 | } |
---|
| 909 | |
---|
| 910 | if ( !_Watchdog_Is_active( &the_thread->Timer ) ) { |
---|
| 911 | _ISR_Enable( level ); |
---|
| 912 | _Thread_Unblock( the_thread ); |
---|
| 913 | } else { |
---|
| 914 | _Watchdog_Deactivate( &the_thread->Timer ); |
---|
| 915 | _ISR_Enable( level ); |
---|
| 916 | (void) _Watchdog_Remove( &the_thread->Timer ); |
---|
| 917 | _Thread_Unblock( the_thread ); |
---|
| 918 | } |
---|
| 919 | |
---|
| 920 | if ( !_Objects_Is_local_id( the_thread->Object.id ) ) |
---|
| 921 | _Thread_MP_Free_proxy( the_thread ); |
---|
| 922 | } |
---|
| 923 | else |
---|
| 924 | _ISR_Enable( level ); |
---|
| 925 | } |
---|
| 926 | |
---|
| 927 | /*PAGE |
---|
| 928 | * |
---|
| 929 | * _Thread_queue_First_priority |
---|
| 930 | * |
---|
| 931 | * This routines returns a pointer to the first thread on the |
---|
| 932 | * specified threadq. |
---|
| 933 | * |
---|
| 934 | * Input parameters: |
---|
| 935 | * the_thread_queue - pointer to thread queue |
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| 936 | * |
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| 937 | * Output parameters: |
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| 938 | * returns - first thread or NULL |
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| 939 | */ |
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| 940 | |
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| 941 | Thread_Control *_Thread_queue_First_priority ( |
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| 942 | Thread_queue_Control *the_thread_queue |
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| 943 | ) |
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| 944 | { |
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| 945 | unsigned32 index; |
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| 946 | |
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| 947 | for( index=0 ; |
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| 948 | index < TASK_QUEUE_DATA_NUMBER_OF_PRIORITY_HEADERS ; |
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| 949 | index++ ) { |
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| 950 | if ( !_Chain_Is_empty( &the_thread_queue->Queues.Priority[ index ] ) ) |
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| 951 | return (Thread_Control *) |
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| 952 | the_thread_queue->Queues.Priority[ index ].first; |
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| 953 | } |
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| 954 | return NULL; |
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| 955 | } |
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