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