[ac7d5ef0] | 1 | /* |
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| 2 | * Thread 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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[63edbb3f] | 13 | * $Id$ |
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[ac7d5ef0] | 14 | */ |
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| 15 | |
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| 16 | #include <rtems/system.h> |
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| 17 | #include <rtems/config.h> |
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| 18 | #include <rtems/context.h> |
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| 19 | #include <rtems/fatal.h> |
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| 20 | #include <rtems/init.h> |
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| 21 | #include <rtems/intthrd.h> |
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| 22 | #include <rtems/isr.h> |
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| 23 | #include <rtems/modes.h> |
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| 24 | #include <rtems/object.h> |
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| 25 | #include <rtems/priority.h> |
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| 26 | #include <rtems/states.h> |
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| 27 | #include <rtems/thread.h> |
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| 28 | #include <rtems/userext.h> |
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| 29 | #include <rtems/wkspace.h> |
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| 30 | |
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| 31 | /*PAGE |
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| 32 | * |
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| 33 | * _Thread_Handler_initialization |
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| 34 | * |
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| 35 | * This routine initializes all thread manager related data structures. |
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| 36 | * |
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| 37 | * Input parameters: |
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| 38 | * maximum_tasks - number of tasks to initialize |
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| 39 | * ticks_per_timeslice - clock ticks per quantum |
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| 40 | * |
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| 41 | * Output parameters: NONE |
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| 42 | */ |
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| 43 | |
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| 44 | void _Thread_Handler_initialization( |
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| 45 | unsigned32 maximum_tasks, |
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| 46 | unsigned32 ticks_per_timeslice, |
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| 47 | unsigned32 maximum_proxies |
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| 48 | ) |
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| 49 | { |
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| 50 | unsigned32 index; |
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| 51 | |
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| 52 | _Context_Switch_necessary = FALSE; |
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| 53 | _Thread_Executing = NULL; |
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| 54 | _Thread_Heir = NULL; |
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| 55 | _Thread_Allocated_fp = NULL; |
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| 56 | |
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| 57 | _Thread_Ticks_remaining_in_timeslice = ticks_per_timeslice; |
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| 58 | _Thread_Ticks_per_timeslice = ticks_per_timeslice; |
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| 59 | |
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| 60 | _Objects_Initialize_information( |
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| 61 | &_Thread_Information, |
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[9863dbf] | 62 | OBJECTS_RTEMS_TASKS, |
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[ac7d5ef0] | 63 | TRUE, |
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| 64 | maximum_tasks, |
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| 65 | sizeof( Thread_Control ) |
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| 66 | ); |
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| 67 | |
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| 68 | _Thread_Ready_chain = _Workspace_Allocate_or_fatal_error( |
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| 69 | (RTEMS_MAXIMUM_PRIORITY + 1) * sizeof(Chain_Control) |
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| 70 | ); |
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| 71 | |
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| 72 | for ( index=0; index <= RTEMS_MAXIMUM_PRIORITY ; index++ ) |
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| 73 | _Chain_Initialize_empty( &_Thread_Ready_chain[ index ] ); |
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| 74 | |
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| 75 | _Thread_MP_Handler_initialization( maximum_proxies ); |
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| 76 | } |
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| 77 | |
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| 78 | /*PAGE |
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| 79 | * |
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| 80 | * _Thread_Start_multitasking |
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| 81 | * |
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| 82 | * This kernel routine readies the requested thread, the thread chain |
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| 83 | * is adjusted. A new heir thread may be selected. |
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| 84 | * |
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| 85 | * Input parameters: |
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| 86 | * system_thread - pointer to system initialization thread control block |
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| 87 | * idle_thread - pointer to idle thread control block |
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| 88 | * |
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| 89 | * Output parameters: NONE |
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| 90 | * |
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| 91 | * NOTE: This routine uses the "blocking" heir selection mechanism. |
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| 92 | * This insures the correct heir after a thread restart. |
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| 93 | * |
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| 94 | * INTERRUPT LATENCY: |
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| 95 | * ready chain |
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| 96 | * select heir |
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| 97 | */ |
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| 98 | |
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| 99 | void _Thread_Start_multitasking( |
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| 100 | Thread_Control *system_thread, |
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| 101 | Thread_Control *idle_thread |
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| 102 | ) |
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| 103 | { |
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| 104 | |
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| 105 | _Thread_Executing = |
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| 106 | _Thread_Heir = |
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| 107 | _Thread_MP_Receive = system_thread; |
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| 108 | |
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| 109 | /* |
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| 110 | * Scheduling will not work "correctly" until the above |
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| 111 | * statements have been executed. |
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| 112 | */ |
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| 113 | |
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| 114 | _Thread_Ready( system_thread ); |
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| 115 | _Thread_Ready( idle_thread ); |
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| 116 | |
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| 117 | _Context_Switch_necessary = FALSE; |
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| 118 | |
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| 119 | _Context_Switch( &_Thread_BSP_context, &system_thread->Registers ); |
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| 120 | |
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| 121 | } |
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| 122 | |
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| 123 | /*PAGE |
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| 124 | * |
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| 125 | * _Thread_Dispatch |
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| 126 | * |
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| 127 | * This kernel routine determines if a dispatch is needed, and if so |
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| 128 | * dispatches to the heir thread. Once the heir is running an attempt |
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| 129 | * is made to dispatch any ASRs. |
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| 130 | * |
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| 131 | * ALTERNATE ENTRY POINTS: |
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| 132 | * void _Thread_Enable_dispatch(); |
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| 133 | * |
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| 134 | * Input parameters: NONE |
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| 135 | * |
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| 136 | * Output parameters: NONE |
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| 137 | * |
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| 138 | * INTERRUPT LATENCY: |
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| 139 | * dispatch thread |
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| 140 | * no dispatch thread |
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| 141 | */ |
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| 142 | |
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| 143 | #if ( CPU_INLINE_ENABLE_DISPATCH == FALSE ) |
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| 144 | void _Thread_Enable_dispatch( void ) |
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| 145 | { |
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| 146 | if ( --_Thread_Dispatch_disable_level ) |
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| 147 | return; |
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| 148 | _Thread_Dispatch(); |
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| 149 | } |
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| 150 | #endif |
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| 151 | |
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| 152 | void _Thread_Dispatch( void ) |
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| 153 | { |
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| 154 | Thread_Control *executing; |
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| 155 | Thread_Control *heir; |
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| 156 | ISR_Level level; |
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| 157 | rtems_signal_set signal_set; |
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| 158 | rtems_mode previous_mode; |
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| 159 | |
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| 160 | executing = _Thread_Executing; |
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| 161 | _ISR_Disable( level ); |
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| 162 | while ( _Context_Switch_necessary == TRUE ) { |
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| 163 | heir = _Thread_Heir; |
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| 164 | _Thread_Dispatch_disable_level = 1; |
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| 165 | _Context_Switch_necessary = FALSE; |
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| 166 | _Thread_Executing = heir; |
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| 167 | _ISR_Enable( level ); |
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| 168 | |
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| 169 | _User_extensions_Task_switch( executing, heir ); |
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| 170 | |
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| 171 | _Thread_Ticks_remaining_in_timeslice = _Thread_Ticks_per_timeslice; |
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| 172 | |
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| 173 | /* |
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| 174 | * If the CPU has hardware floating point, then we must address saving |
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| 175 | * and restoring it as part of the context switch. |
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| 176 | * |
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| 177 | * The second conditional compilation section selects the algorithm used |
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| 178 | * to context switch between floating point tasks. The deferred algorithm |
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| 179 | * can be significantly better in a system with few floating point tasks |
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| 180 | * because it reduces the total number of save and restore FP context |
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| 181 | * operations. However, this algorithm can not be used on all CPUs due |
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| 182 | * to unpredictable use of FP registers by some compilers for integer |
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| 183 | * operations. |
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| 184 | */ |
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| 185 | |
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| 186 | #if ( CPU_HARDWARE_FP == TRUE ) |
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| 187 | #if ( CPU_USE_DEFERRED_FP_SWITCH == TRUE ) |
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| 188 | if ( (heir->fp_context != NULL) && !_Thread_Is_allocated_fp( heir ) ) { |
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| 189 | if ( _Thread_Allocated_fp != NULL ) |
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| 190 | _Context_Save_fp( &_Thread_Allocated_fp->fp_context ); |
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| 191 | _Context_Restore_fp( &heir->fp_context ); |
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| 192 | _Thread_Allocated_fp = heir; |
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| 193 | } |
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| 194 | #else |
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| 195 | if ( executing->fp_context != NULL ) |
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| 196 | _Context_Save_fp( &executing->fp_context ); |
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| 197 | |
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| 198 | if ( heir->fp_context != NULL ) |
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| 199 | _Context_Restore_fp( &heir->fp_context ); |
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| 200 | #endif |
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| 201 | #endif |
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| 202 | |
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| 203 | _Context_Switch( &executing->Registers, &heir->Registers ); |
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| 204 | |
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| 205 | executing = _Thread_Executing; |
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| 206 | _ISR_Disable( level ); |
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| 207 | } |
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| 208 | |
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| 209 | _Thread_Dispatch_disable_level = 0; |
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| 210 | |
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| 211 | if ( _ASR_Are_signals_pending( &executing->Signal ) ) { |
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| 212 | signal_set = executing->Signal.signals_posted; |
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| 213 | executing->Signal.signals_posted = 0; |
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| 214 | _ISR_Enable( level ); |
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| 215 | |
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| 216 | executing->Signal.nest_level += 1; |
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| 217 | if (_Thread_Change_mode( executing->Signal.mode_set, |
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| 218 | RTEMS_ALL_MODE_MASKS, &previous_mode )) |
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| 219 | _Thread_Dispatch(); |
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| 220 | |
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| 221 | (*executing->Signal.handler)( signal_set ); |
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| 222 | |
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| 223 | executing->Signal.nest_level -= 1; |
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| 224 | if (_Thread_Change_mode( previous_mode, |
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| 225 | RTEMS_ALL_MODE_MASKS, &previous_mode )) |
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| 226 | _Thread_Dispatch(); |
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| 227 | } |
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| 228 | else |
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| 229 | _ISR_Enable( level ); |
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| 230 | } |
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| 231 | |
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| 232 | /*PAGE |
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| 233 | * |
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| 234 | * _Thread_Ready |
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| 235 | * |
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| 236 | * This kernel routine readies the requested thread, the thread chain |
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| 237 | * is adjusted. A new heir thread may be selected. |
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| 238 | * |
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| 239 | * Input parameters: |
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| 240 | * the_thread - pointer to thread control block |
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| 241 | * |
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| 242 | * Output parameters: NONE |
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| 243 | * |
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| 244 | * NOTE: This routine uses the "blocking" heir selection mechanism. |
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| 245 | * This insures the correct heir after a thread restart. |
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| 246 | * |
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| 247 | * INTERRUPT LATENCY: |
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| 248 | * ready chain |
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| 249 | * select heir |
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| 250 | */ |
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| 251 | |
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| 252 | void _Thread_Ready( |
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| 253 | Thread_Control *the_thread |
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| 254 | ) |
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| 255 | { |
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| 256 | ISR_Level level; |
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| 257 | Thread_Control *heir; |
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| 258 | |
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| 259 | _ISR_Disable( level ); |
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| 260 | |
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| 261 | the_thread->current_state = STATES_READY; |
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| 262 | |
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| 263 | _Priority_Add_to_bit_map( &the_thread->Priority_map ); |
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| 264 | |
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| 265 | _Chain_Append_unprotected( the_thread->ready, &the_thread->Object.Node ); |
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| 266 | |
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| 267 | _ISR_Flash( level ); |
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| 268 | |
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| 269 | _Thread_Calculate_heir(); |
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| 270 | |
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| 271 | heir = _Thread_Heir; |
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| 272 | |
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| 273 | if ( !_Thread_Is_executing( heir ) && |
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| 274 | _Modes_Is_preempt( _Thread_Executing->current_modes ) ) |
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| 275 | _Context_Switch_necessary = TRUE; |
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| 276 | |
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| 277 | _ISR_Enable( level ); |
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| 278 | } |
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| 279 | |
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| 280 | /*PAGE |
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| 281 | * |
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| 282 | * _Thread_Clear_state |
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| 283 | * |
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| 284 | * This kernel routine clears the appropriate states in the |
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| 285 | * requested thread. The thread ready chain is adjusted if |
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| 286 | * necessary and the Heir thread is set accordingly. |
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| 287 | * |
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| 288 | * Input parameters: |
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| 289 | * the_thread - pointer to thread control block |
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| 290 | * state - state set to clear |
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| 291 | * |
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| 292 | * Output parameters: NONE |
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| 293 | * |
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| 294 | * INTERRUPT LATENCY: |
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| 295 | * priority map |
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| 296 | * select heir |
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| 297 | */ |
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| 298 | |
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| 299 | void _Thread_Clear_state( |
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| 300 | Thread_Control *the_thread, |
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| 301 | States_Control state |
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| 302 | ) |
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| 303 | { |
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| 304 | ISR_Level level; |
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| 305 | |
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| 306 | _ISR_Disable( level ); |
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| 307 | the_thread->current_state = |
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| 308 | _States_Clear( state, the_thread->current_state ); |
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| 309 | |
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| 310 | if ( _States_Is_ready( the_thread->current_state ) ) { |
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| 311 | |
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| 312 | _Priority_Add_to_bit_map( &the_thread->Priority_map ); |
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| 313 | |
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| 314 | _Chain_Append_unprotected( the_thread->ready, &the_thread->Object.Node ); |
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| 315 | |
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| 316 | _ISR_Flash( level ); |
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| 317 | |
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| 318 | if ( the_thread->current_priority < _Thread_Heir->current_priority ) { |
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| 319 | _Thread_Heir = the_thread; |
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[3a5dbdc] | 320 | if ( _Modes_Is_preempt( _Thread_Executing->current_modes ) || |
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| 321 | the_thread->current_priority == 0 ) |
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[ac7d5ef0] | 322 | _Context_Switch_necessary = TRUE; |
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| 323 | } |
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| 324 | } |
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| 325 | _ISR_Enable( level ); |
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| 326 | } |
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| 327 | |
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| 328 | /*PAGE |
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| 329 | * |
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| 330 | * _Thread_Set_state |
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| 331 | * |
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| 332 | * This kernel routine sets the requested state in the THREAD. The |
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| 333 | * THREAD chain is adjusted if necessary. |
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| 334 | * |
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| 335 | * Input parameters: |
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| 336 | * the_thread - pointer to thread control block |
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| 337 | * state - state to be set |
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| 338 | * |
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| 339 | * Output parameters: NONE |
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| 340 | * |
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| 341 | * INTERRUPT LATENCY: |
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| 342 | * ready chain |
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| 343 | * select map |
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| 344 | */ |
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| 345 | |
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| 346 | void _Thread_Set_state( |
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| 347 | Thread_Control *the_thread, |
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| 348 | States_Control state |
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| 349 | ) |
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| 350 | { |
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| 351 | ISR_Level level; |
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| 352 | Chain_Control *ready; |
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| 353 | |
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| 354 | ready = the_thread->ready; |
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| 355 | _ISR_Disable( level ); |
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| 356 | if ( !_States_Is_ready( the_thread->current_state ) ) { |
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| 357 | the_thread->current_state = |
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| 358 | _States_Set( state, the_thread->current_state ); |
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| 359 | _ISR_Enable( level ); |
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| 360 | return; |
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| 361 | } |
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| 362 | |
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| 363 | the_thread->current_state = state; |
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| 364 | |
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| 365 | if ( _Chain_Has_only_one_node( ready ) ) { |
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| 366 | |
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| 367 | _Chain_Initialize_empty( ready ); |
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| 368 | _Priority_Remove_from_bit_map( &the_thread->Priority_map ); |
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| 369 | |
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| 370 | } else |
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| 371 | _Chain_Extract_unprotected( &the_thread->Object.Node ); |
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| 372 | |
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| 373 | _ISR_Flash( level ); |
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| 374 | |
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| 375 | if ( _Thread_Is_heir( the_thread ) ) |
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| 376 | _Thread_Calculate_heir(); |
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| 377 | |
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| 378 | if ( _Thread_Is_executing( the_thread ) ) |
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| 379 | _Context_Switch_necessary = TRUE; |
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| 380 | |
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| 381 | _ISR_Enable( level ); |
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| 382 | } |
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| 383 | |
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| 384 | /*PAGE |
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| 385 | * |
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| 386 | * _Thread_Set_transient |
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| 387 | * |
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| 388 | * This kernel routine places the requested thread in the transient state |
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| 389 | * which will remove it from the ready queue, if necessary. No |
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| 390 | * rescheduling is necessary because it is assumed that the transient |
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| 391 | * state will be cleared before dispatching is enabled. |
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| 392 | * |
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| 393 | * Input parameters: |
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| 394 | * the_thread - pointer to thread control block |
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| 395 | * |
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| 396 | * Output parameters: NONE |
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| 397 | * |
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| 398 | * INTERRUPT LATENCY: |
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| 399 | * only case |
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| 400 | */ |
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| 401 | |
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| 402 | void _Thread_Set_transient( |
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| 403 | Thread_Control *the_thread |
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| 404 | ) |
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| 405 | { |
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| 406 | ISR_Level level; |
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| 407 | unsigned32 old_state; |
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| 408 | Chain_Control *ready; |
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| 409 | |
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| 410 | ready = the_thread->ready; |
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| 411 | _ISR_Disable( level ); |
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| 412 | |
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| 413 | old_state = the_thread->current_state; |
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| 414 | the_thread->current_state = _States_Set( STATES_TRANSIENT, old_state ); |
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| 415 | |
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| 416 | if ( _States_Is_ready( old_state ) ) { |
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| 417 | if ( _Chain_Has_only_one_node( ready ) ) { |
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| 418 | |
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| 419 | _Chain_Initialize_empty( ready ); |
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| 420 | _Priority_Remove_from_bit_map( &the_thread->Priority_map ); |
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| 421 | |
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| 422 | } else |
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| 423 | _Chain_Extract_unprotected( &the_thread->Object.Node ); |
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| 424 | } |
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| 425 | |
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| 426 | _ISR_Enable( level ); |
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| 427 | |
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| 428 | } |
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| 429 | |
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| 430 | /*PAGE |
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| 431 | * |
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| 432 | * _Thread_Reset_timeslice |
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| 433 | * |
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| 434 | * This routine will remove the running thread from the ready chain |
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| 435 | * and place it immediately at the rear of this chain and then the |
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| 436 | * timeslice counter is reset. The heir THREAD will be updated if |
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| 437 | * the running is also the currently the heir. |
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| 438 | * |
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| 439 | * Input parameters: NONE |
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| 440 | * |
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| 441 | * Output parameters: NONE |
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| 442 | * |
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| 443 | * INTERRUPT LATENCY: |
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| 444 | * ready chain |
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| 445 | * select heir |
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| 446 | */ |
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| 447 | |
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| 448 | void _Thread_Reset_timeslice( void ) |
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| 449 | { |
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| 450 | ISR_Level level; |
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| 451 | Thread_Control *executing; |
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| 452 | Chain_Control *ready; |
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| 453 | |
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| 454 | executing = _Thread_Executing; |
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| 455 | ready = executing->ready; |
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| 456 | _ISR_Disable( level ); |
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| 457 | if ( _Chain_Has_only_one_node( ready ) ) { |
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| 458 | _Thread_Ticks_remaining_in_timeslice = _Thread_Ticks_per_timeslice; |
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| 459 | _ISR_Enable( level ); |
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| 460 | return; |
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| 461 | } |
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| 462 | _Chain_Extract_unprotected( &executing->Object.Node ); |
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| 463 | _Chain_Append_unprotected( ready, &executing->Object.Node ); |
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| 464 | |
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| 465 | _ISR_Flash( level ); |
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| 466 | |
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| 467 | if ( _Thread_Is_heir( executing ) ) |
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| 468 | _Thread_Heir = (Thread_Control *) ready->first; |
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| 469 | |
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| 470 | _Context_Switch_necessary = TRUE; |
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| 471 | |
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| 472 | _ISR_Enable( level ); |
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| 473 | } |
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| 474 | |
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| 475 | /*PAGE |
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| 476 | * |
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| 477 | * _Thread_Tickle_timeslice |
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| 478 | * |
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| 479 | * This scheduler routine determines if timeslicing is enabled |
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| 480 | * for the currently executing thread and, if so, updates the |
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| 481 | * timeslice count and checks for timeslice expiration. |
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| 482 | * |
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| 483 | * Input parameters: NONE |
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| 484 | * |
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| 485 | * Output parameters: NONE |
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| 486 | */ |
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| 487 | |
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| 488 | void _Thread_Tickle_timeslice( void ) |
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| 489 | { |
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| 490 | if ( ( _Modes_Is_timeslice(_Thread_Executing->current_modes) ) && |
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| 491 | ( _States_Is_ready( _Thread_Executing->current_state ) ) && |
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| 492 | ( --_Thread_Ticks_remaining_in_timeslice == 0 ) ) { |
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| 493 | _Thread_Reset_timeslice(); |
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| 494 | } |
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| 495 | } |
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| 496 | |
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| 497 | /*PAGE |
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| 498 | * |
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| 499 | * _Thread_Yield_processor |
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| 500 | * |
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| 501 | * This kernel routine will remove the running THREAD from the ready chain |
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| 502 | * and place it immediatly at the rear of this chain. Reset timeslice |
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| 503 | * and yield the processor functions both use this routine, therefore if |
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| 504 | * reset is TRUE and this is the only thread on the chain then the |
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| 505 | * timeslice counter is reset. The heir THREAD will be updated if the |
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| 506 | * running is also the currently the heir. |
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| 507 | * |
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| 508 | * Input parameters: NONE |
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| 509 | * |
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| 510 | * Output parameters: NONE |
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| 511 | * |
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| 512 | * INTERRUPT LATENCY: |
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| 513 | * ready chain |
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| 514 | * select heir |
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| 515 | */ |
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| 516 | |
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| 517 | void _Thread_Yield_processor( void ) |
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| 518 | { |
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| 519 | ISR_Level level; |
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| 520 | Thread_Control *executing; |
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| 521 | Chain_Control *ready; |
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| 522 | |
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| 523 | executing = _Thread_Executing; |
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| 524 | ready = executing->ready; |
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| 525 | _ISR_Disable( level ); |
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| 526 | if ( !_Chain_Has_only_one_node( ready ) ) { |
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| 527 | _Chain_Extract_unprotected( &executing->Object.Node ); |
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| 528 | _Chain_Append_unprotected( ready, &executing->Object.Node ); |
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| 529 | |
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| 530 | _ISR_Flash( level ); |
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| 531 | |
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| 532 | if ( _Thread_Is_heir( executing ) ) |
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| 533 | _Thread_Heir = (Thread_Control *) ready->first; |
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| 534 | _Context_Switch_necessary = TRUE; |
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| 535 | } |
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| 536 | else if ( !_Thread_Is_heir( executing ) ) |
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| 537 | _Context_Switch_necessary = TRUE; |
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| 538 | |
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| 539 | _ISR_Enable( level ); |
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| 540 | } |
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| 541 | |
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| 542 | /*PAGE |
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| 543 | * |
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| 544 | * _Thread_Load_environment |
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| 545 | * |
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| 546 | * Load starting environment for another thread from its start area in the |
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| 547 | * thread. Only called from t_restart and t_start. |
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| 548 | * |
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| 549 | * Input parameters: |
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| 550 | * the_thread - thread control block pointer |
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| 551 | * |
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| 552 | * Output parameters: NONE |
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| 553 | */ |
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| 554 | |
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| 555 | void _Thread_Load_environment( |
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| 556 | Thread_Control *the_thread |
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| 557 | ) |
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| 558 | { |
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| 559 | if ( the_thread->Start.fp_context ) { |
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| 560 | the_thread->fp_context = the_thread->Start.fp_context; |
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| 561 | _Context_Initialize_fp( &the_thread->fp_context ); |
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| 562 | } |
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| 563 | |
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| 564 | _Context_Initialize( |
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| 565 | &the_thread->Registers, |
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| 566 | the_thread->Start.Initial_stack.area, |
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| 567 | the_thread->Start.Initial_stack.size, |
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| 568 | _Modes_Get_interrupt_level( the_thread->Start.initial_modes ), |
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| 569 | _Thread_Handler |
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| 570 | ); |
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| 571 | |
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| 572 | } |
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| 573 | |
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| 574 | /*PAGE |
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| 575 | * |
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| 576 | * _Thread_Handler |
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| 577 | * |
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| 578 | * This routine is the default thread exitted error handler. It is |
---|
| 579 | * returned to when a thread exits. The configured fatal error handler |
---|
| 580 | * is invoked to process the exit. |
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| 581 | * |
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| 582 | * Input parameters: NONE |
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| 583 | * |
---|
| 584 | * Output parameters: NONE |
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| 585 | */ |
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| 586 | |
---|
| 587 | void _Thread_Handler( void ) |
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| 588 | { |
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| 589 | Thread_Control *executing; |
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| 590 | |
---|
| 591 | executing = _Thread_Executing; |
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| 592 | |
---|
| 593 | /* |
---|
[7979e35] | 594 | * Take care that 'begin' extensions get to complete before |
---|
| 595 | * 'switch' extensions can run. This means must keep dispatch |
---|
| 596 | * disabled until all 'begin' extensions complete. |
---|
[ac7d5ef0] | 597 | */ |
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[7979e35] | 598 | |
---|
[ac7d5ef0] | 599 | _User_extensions_Task_begin( executing ); |
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[7979e35] | 600 | |
---|
| 601 | /* |
---|
| 602 | * At this point, the dispatch disable level BETTER be 1. |
---|
| 603 | */ |
---|
[ac7d5ef0] | 604 | |
---|
[7979e35] | 605 | _Thread_Enable_dispatch(); |
---|
| 606 | |
---|
[ac7d5ef0] | 607 | (*executing->Start.entry_point)( executing->Start.initial_argument ); |
---|
| 608 | |
---|
| 609 | _User_extensions_Task_exitted( executing ); |
---|
| 610 | |
---|
| 611 | rtems_fatal_error_occurred( RTEMS_TASK_EXITTED ); |
---|
| 612 | } |
---|
| 613 | |
---|
| 614 | /*PAGE |
---|
| 615 | * |
---|
| 616 | * _Thread_Delay_ended |
---|
| 617 | * |
---|
| 618 | * This routine processes a thread whose delay period has ended. |
---|
| 619 | * It is called by the watchdog handler. |
---|
| 620 | * |
---|
| 621 | * Input parameters: |
---|
| 622 | * id - thread id |
---|
| 623 | * |
---|
| 624 | * Output parameters: NONE |
---|
| 625 | */ |
---|
| 626 | |
---|
| 627 | void _Thread_Delay_ended( |
---|
| 628 | Objects_Id id, |
---|
| 629 | void *ignored |
---|
| 630 | ) |
---|
| 631 | { |
---|
[45819022] | 632 | Thread_Control *the_thread; |
---|
| 633 | Objects_Locations location; |
---|
[ac7d5ef0] | 634 | |
---|
| 635 | the_thread = _Thread_Get( id, &location ); |
---|
| 636 | switch ( location ) { |
---|
| 637 | case OBJECTS_ERROR: |
---|
| 638 | case OBJECTS_REMOTE: /* impossible */ |
---|
| 639 | break; |
---|
| 640 | case OBJECTS_LOCAL: |
---|
| 641 | _Thread_Unblock( the_thread ); |
---|
| 642 | _Thread_Unnest_dispatch(); |
---|
| 643 | break; |
---|
| 644 | } |
---|
| 645 | } |
---|
| 646 | |
---|
| 647 | /*PAGE |
---|
| 648 | * |
---|
| 649 | * _Thread_Change_priority |
---|
| 650 | * |
---|
| 651 | * This kernel routine changes the priority of the thread. The |
---|
| 652 | * thread chain is adjusted if necessary. |
---|
| 653 | * |
---|
| 654 | * Input parameters: |
---|
| 655 | * the_thread - pointer to thread control block |
---|
| 656 | * new_priority - ultimate priority |
---|
| 657 | * |
---|
| 658 | * Output parameters: NONE |
---|
| 659 | * |
---|
| 660 | * INTERRUPT LATENCY: |
---|
| 661 | * ready chain |
---|
| 662 | * select heir |
---|
| 663 | */ |
---|
| 664 | |
---|
| 665 | void _Thread_Change_priority( |
---|
| 666 | Thread_Control *the_thread, |
---|
| 667 | rtems_task_priority new_priority |
---|
| 668 | ) |
---|
| 669 | { |
---|
| 670 | ISR_Level level; |
---|
| 671 | |
---|
| 672 | _Thread_Set_transient( the_thread ); |
---|
| 673 | |
---|
| 674 | if ( the_thread->current_priority != new_priority ) |
---|
| 675 | _Thread_Set_priority( the_thread, new_priority ); |
---|
| 676 | |
---|
| 677 | _ISR_Disable( level ); |
---|
| 678 | |
---|
| 679 | the_thread->current_state = |
---|
| 680 | _States_Clear( STATES_TRANSIENT, the_thread->current_state ); |
---|
| 681 | |
---|
| 682 | if ( ! _States_Is_ready( the_thread->current_state ) ) { |
---|
| 683 | _ISR_Enable( level ); |
---|
| 684 | return; |
---|
| 685 | } |
---|
| 686 | |
---|
| 687 | _Priority_Add_to_bit_map( &the_thread->Priority_map ); |
---|
| 688 | _Chain_Append_unprotected( the_thread->ready, &the_thread->Object.Node ); |
---|
| 689 | |
---|
| 690 | _ISR_Flash( level ); |
---|
| 691 | |
---|
| 692 | _Thread_Calculate_heir(); |
---|
| 693 | |
---|
| 694 | if ( !_Thread_Is_executing_also_the_heir() && |
---|
| 695 | _Modes_Is_preempt(_Thread_Executing->current_modes) ) |
---|
| 696 | _Context_Switch_necessary = TRUE; |
---|
| 697 | |
---|
| 698 | _ISR_Enable( level ); |
---|
| 699 | } |
---|
| 700 | |
---|
| 701 | /*PAGE |
---|
| 702 | * |
---|
| 703 | * _Thread_Set_priority |
---|
| 704 | * |
---|
| 705 | * This directive enables and disables several modes of |
---|
| 706 | * execution for the requesting thread. |
---|
| 707 | * |
---|
| 708 | * Input parameters: |
---|
| 709 | * the_thread - pointer to thread priority |
---|
| 710 | * new_priority - new priority |
---|
| 711 | * |
---|
| 712 | * Output: NONE |
---|
| 713 | */ |
---|
| 714 | |
---|
| 715 | void _Thread_Set_priority( |
---|
| 716 | Thread_Control *the_thread, |
---|
| 717 | rtems_task_priority new_priority |
---|
| 718 | ) |
---|
| 719 | { |
---|
| 720 | the_thread->current_priority = new_priority; |
---|
| 721 | the_thread->ready = &_Thread_Ready_chain[ new_priority ]; |
---|
| 722 | |
---|
| 723 | _Priority_Initialize_information( &the_thread->Priority_map, new_priority ); |
---|
| 724 | } |
---|
| 725 | |
---|
| 726 | /*PAGE |
---|
| 727 | * |
---|
| 728 | * _Thread_Change_mode |
---|
| 729 | * |
---|
| 730 | * This routine enables and disables several modes of |
---|
| 731 | * execution for the requesting thread. |
---|
| 732 | * |
---|
| 733 | * Input parameters: |
---|
| 734 | * mode - new mode |
---|
| 735 | * mask - mask |
---|
| 736 | * old_mode_set - address of previous mode |
---|
| 737 | * |
---|
| 738 | * Output: |
---|
| 739 | * *old_mode_set - previous mode |
---|
| 740 | * returns TRUE if scheduling necessary |
---|
| 741 | * |
---|
| 742 | * INTERRUPT LATENCY: |
---|
| 743 | * only one case |
---|
| 744 | */ |
---|
| 745 | |
---|
| 746 | boolean _Thread_Change_mode( |
---|
| 747 | unsigned32 new_mode_set, |
---|
| 748 | unsigned32 mask, |
---|
| 749 | unsigned32 *old_mode_set |
---|
| 750 | ) |
---|
| 751 | { |
---|
| 752 | rtems_mode changed; |
---|
| 753 | rtems_mode threads_new_mode_set; |
---|
| 754 | Thread_Control *executing; |
---|
| 755 | boolean need_dispatch; |
---|
| 756 | |
---|
| 757 | executing = _Thread_Executing; |
---|
| 758 | *old_mode_set = executing->current_modes; |
---|
| 759 | |
---|
| 760 | _Modes_Change( executing->current_modes, |
---|
| 761 | new_mode_set, mask, &threads_new_mode_set, &changed ); |
---|
| 762 | |
---|
| 763 | _Modes_Set_interrupt_level( threads_new_mode_set ); |
---|
| 764 | |
---|
| 765 | if ( _Modes_Mask_changed( changed, RTEMS_ASR_MASK ) ) |
---|
| 766 | _ASR_Swap_signals( &executing->Signal ); |
---|
| 767 | |
---|
| 768 | executing->current_modes = threads_new_mode_set; |
---|
| 769 | need_dispatch = TRUE; |
---|
| 770 | |
---|
| 771 | if ( !_States_Is_ready( executing->current_state ) || |
---|
| 772 | ( !_Thread_Is_heir( executing ) && |
---|
| 773 | _Modes_Is_preempt(threads_new_mode_set) ) ) |
---|
| 774 | |
---|
| 775 | _Context_Switch_necessary = TRUE; |
---|
| 776 | |
---|
| 777 | else if ( !_ASR_Are_signals_pending( &executing->Signal ) ) |
---|
| 778 | |
---|
| 779 | need_dispatch = FALSE; |
---|
| 780 | |
---|
| 781 | return need_dispatch; |
---|
| 782 | } |
---|
| 783 | |
---|
| 784 | /*PAGE |
---|
| 785 | * |
---|
| 786 | * _Thread_Get |
---|
| 787 | * |
---|
| 788 | * NOTE: If we are not using static inlines, this must be a real |
---|
| 789 | * subroutine call. |
---|
| 790 | */ |
---|
| 791 | |
---|
| 792 | #ifndef USE_INLINES |
---|
| 793 | |
---|
| 794 | STATIC INLINE Thread_Control *_Thread_Get ( |
---|
[45819022] | 795 | Objects_Id id, |
---|
| 796 | Objects_Locations *location |
---|
[ac7d5ef0] | 797 | ) |
---|
| 798 | { |
---|
| 799 | if ( _Objects_Are_ids_equal( id, OBJECTS_ID_OF_SELF ) ) { |
---|
| 800 | _Thread_Disable_dispatch(); |
---|
| 801 | *location = OBJECTS_LOCAL; |
---|
| 802 | return( _Thread_Executing ); |
---|
| 803 | } |
---|
| 804 | |
---|
| 805 | return (Thread_Control *) _Objects_Get( &_Thread_Information, id, location ); |
---|
| 806 | } |
---|
| 807 | #endif |
---|
| 808 | |
---|