1 | /** |
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2 | * @file timerserver.c |
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3 | * |
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4 | * Timer Manager - rtems_timer_initiate_server directive along with |
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5 | * the Timer Server Body and support routines |
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6 | * |
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7 | * @note Data specific to the Timer Server is declared in this |
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8 | * file as the Timer Server so it does not have to be in the |
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9 | * minimum footprint. It is only really required when |
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10 | * task-based timers are used. Since task-based timers can |
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11 | * not be started until the server is initiated, this structure |
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12 | * does not have to be initialized until then. |
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13 | */ |
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14 | |
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15 | /* COPYRIGHT (c) 1989-2008. |
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16 | * On-Line Applications Research Corporation (OAR). |
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17 | * |
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18 | * Copyright (c) 2009, 2017 embedded brains GmbH. |
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19 | * |
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20 | * The license and distribution terms for this file may be |
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21 | * found in the file LICENSE in this distribution or at |
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22 | * http://www.rtems.org/license/LICENSE. |
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23 | */ |
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24 | |
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25 | #if HAVE_CONFIG_H |
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26 | #include "config.h" |
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27 | #endif |
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28 | |
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29 | #include <rtems.h> |
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30 | #include <rtems/rtems/timerimpl.h> |
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31 | #include <rtems/rtems/tasksimpl.h> |
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32 | #include <rtems/score/onceimpl.h> |
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33 | #include <rtems/score/todimpl.h> |
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34 | |
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35 | static Timer_server_Control _Timer_server_Default; |
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36 | |
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37 | static void _Timer_server_Acquire( |
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38 | Timer_server_Control *ts, |
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39 | ISR_lock_Context *lock_context |
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40 | ) |
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41 | { |
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42 | _ISR_lock_ISR_disable_and_acquire( &ts->Lock, lock_context ); |
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43 | } |
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44 | |
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45 | static void _Timer_server_Release( |
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46 | Timer_server_Control *ts, |
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47 | ISR_lock_Context *lock_context |
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48 | ) |
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49 | { |
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50 | _ISR_lock_Release_and_ISR_enable( &ts->Lock, lock_context ); |
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51 | } |
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52 | |
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53 | void _Timer_server_Routine_adaptor( Watchdog_Control *the_watchdog ) |
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54 | { |
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55 | Timer_Control *the_timer; |
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56 | ISR_lock_Context lock_context; |
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57 | Per_CPU_Control *cpu; |
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58 | Timer_server_Control *ts; |
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59 | bool wakeup; |
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60 | |
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61 | ts = _Timer_server; |
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62 | _Assert( ts != NULL ); |
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63 | the_timer = RTEMS_CONTAINER_OF( the_watchdog, Timer_Control, Ticker ); |
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64 | |
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65 | _Timer_server_Acquire( ts, &lock_context ); |
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66 | |
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67 | _Assert( _Watchdog_Get_state( &the_timer->Ticker ) == WATCHDOG_INACTIVE ); |
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68 | _Watchdog_Set_state( &the_timer->Ticker, WATCHDOG_PENDING ); |
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69 | cpu = _Watchdog_Get_CPU( &the_timer->Ticker ); |
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70 | the_timer->stop_time = _Timer_Get_CPU_ticks( cpu ); |
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71 | wakeup = _Chain_Is_empty( &ts->Pending ); |
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72 | _Chain_Append_unprotected( &ts->Pending, &the_timer->Ticker.Node.Chain ); |
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73 | |
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74 | _Timer_server_Release( ts, &lock_context ); |
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75 | |
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76 | if ( wakeup ) { |
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77 | (void) rtems_event_system_send( ts->server_id, RTEMS_EVENT_SYSTEM_SERVER ); |
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78 | } |
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79 | } |
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80 | |
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81 | /** |
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82 | * @brief Timer server body. |
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83 | * |
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84 | * This is the server for task based timers. This task executes whenever a |
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85 | * task-based timer should fire. It services both "after" and "when" timers. |
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86 | * It is not created automatically but must be created explicitly by the |
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87 | * application before task-based timers may be initiated. The parameter |
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88 | * @a arg points to the corresponding timer server control block. |
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89 | */ |
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90 | static rtems_task _Timer_server_Body( |
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91 | rtems_task_argument arg |
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92 | ) |
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93 | { |
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94 | Timer_server_Control *ts = (Timer_server_Control *) arg; |
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95 | #if defined(RTEMS_SCORE_THREAD_ENABLE_RESOURCE_COUNT) |
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96 | Thread_Control *executing = _Thread_Get_executing(); |
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97 | #endif |
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98 | |
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99 | while ( true ) { |
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100 | ISR_lock_Context lock_context; |
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101 | rtems_event_set events; |
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102 | |
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103 | _Timer_server_Acquire( ts, &lock_context ); |
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104 | |
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105 | while ( true ) { |
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106 | Watchdog_Control *the_watchdog; |
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107 | Timer_Control *the_timer; |
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108 | rtems_timer_service_routine_entry routine; |
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109 | Objects_Id id; |
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110 | void *user_data; |
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111 | |
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112 | the_watchdog = (Watchdog_Control *) _Chain_Get_unprotected( &ts->Pending ); |
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113 | if ( the_watchdog == NULL ) { |
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114 | break; |
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115 | } |
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116 | |
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117 | _Assert( _Watchdog_Get_state( the_watchdog ) == WATCHDOG_PENDING ); |
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118 | _Watchdog_Set_state( the_watchdog, WATCHDOG_INACTIVE ); |
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119 | the_timer = RTEMS_CONTAINER_OF( the_watchdog, Timer_Control, Ticker ); |
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120 | routine = the_timer->routine; |
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121 | id = the_timer->Object.id; |
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122 | user_data = the_timer->user_data; |
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123 | |
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124 | _Timer_server_Release( ts, &lock_context ); |
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125 | |
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126 | ( *routine )( id, user_data ); |
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127 | #if defined(RTEMS_SCORE_THREAD_ENABLE_RESOURCE_COUNT) |
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128 | _Assert( !_Thread_Owns_resources( executing ) ); |
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129 | #endif |
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130 | |
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131 | _Timer_server_Acquire( ts, &lock_context ); |
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132 | } |
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133 | |
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134 | _Timer_server_Release( ts, &lock_context ); |
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135 | |
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136 | (void) rtems_event_system_receive( |
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137 | RTEMS_EVENT_SYSTEM_SERVER, |
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138 | RTEMS_EVENT_ALL | RTEMS_WAIT, |
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139 | RTEMS_NO_TIMEOUT, |
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140 | &events |
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141 | ); |
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142 | } |
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143 | } |
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144 | |
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145 | static rtems_status_code _Timer_server_Initiate( |
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146 | rtems_task_priority priority, |
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147 | size_t stack_size, |
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148 | rtems_attribute attribute_set |
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149 | ) |
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150 | { |
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151 | rtems_status_code status; |
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152 | rtems_id id; |
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153 | Timer_server_Control *ts; |
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154 | |
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155 | /* |
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156 | * Just to make sure this is only called once. |
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157 | */ |
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158 | if ( _Timer_server != NULL ) { |
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159 | return RTEMS_INCORRECT_STATE; |
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160 | } |
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161 | |
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162 | if ( priority == RTEMS_TIMER_SERVER_DEFAULT_PRIORITY ) { |
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163 | priority = PRIORITY_PSEUDO_ISR; |
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164 | } |
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165 | |
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166 | /* |
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167 | * Create the Timer Server with the name the name of "TIME". The attribute |
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168 | * RTEMS_SYSTEM_TASK allows us to set a priority to 0 which will makes it |
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169 | * higher than any other task in the system. It can be viewed as a low |
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170 | * priority interrupt. It is also always NO_PREEMPT so it looks like |
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171 | * an interrupt to other tasks. |
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172 | * |
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173 | * We allow the user to override the default priority because the Timer |
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174 | * Server can invoke TSRs which must adhere to language run-time or |
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175 | * other library rules. For example, if using a TSR written in Ada the |
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176 | * Server should run at the same priority as the priority Ada task. |
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177 | * Otherwise, the priority ceiling for the mutex used to protect the |
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178 | * GNAT run-time is violated. |
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179 | */ |
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180 | status = rtems_task_create( |
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181 | rtems_build_name('T','I','M','E'), |
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182 | priority, |
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183 | stack_size, |
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184 | rtems_configuration_is_smp_enabled() ? |
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185 | RTEMS_DEFAULT_MODES : /* no preempt is not supported for SMP */ |
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186 | RTEMS_NO_PREEMPT, /* no preempt is like an interrupt */ |
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187 | /* user may want floating point but we need */ |
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188 | /* system task specified for 0 priority */ |
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189 | attribute_set | RTEMS_SYSTEM_TASK, |
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190 | &id |
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191 | ); |
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192 | if (status != RTEMS_SUCCESSFUL) { |
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193 | return status; |
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194 | } |
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195 | |
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196 | /* |
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197 | * Do all the data structure initialization before starting the |
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198 | * Timer Server so we do not have to have a critical section. |
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199 | */ |
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200 | |
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201 | ts = &_Timer_server_Default; |
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202 | _ISR_lock_Initialize( &ts->Lock, "Timer Server" ); |
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203 | _Chain_Initialize_empty( &ts->Pending ); |
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204 | ts->server_id = id; |
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205 | |
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206 | /* |
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207 | * The default timer server is now available. |
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208 | */ |
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209 | _Timer_server = ts; |
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210 | |
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211 | /* |
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212 | * Start the timer server |
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213 | */ |
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214 | status = rtems_task_start( |
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215 | id, |
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216 | _Timer_server_Body, |
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217 | (rtems_task_argument) ts |
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218 | ); |
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219 | _Assert( status == RTEMS_SUCCESSFUL ); |
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220 | |
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221 | return status; |
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222 | } |
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223 | |
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224 | rtems_status_code rtems_timer_initiate_server( |
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225 | rtems_task_priority priority, |
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226 | size_t stack_size, |
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227 | rtems_attribute attribute_set |
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228 | ) |
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229 | { |
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230 | rtems_status_code status; |
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231 | Thread_Life_state thread_life_state; |
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232 | |
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233 | thread_life_state = _Once_Lock(); |
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234 | status = _Timer_server_Initiate( priority, stack_size, attribute_set ); |
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235 | _Once_Unlock( thread_life_state ); |
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236 | |
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237 | return status; |
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238 | } |
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