1 | // |
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2 | // Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo |
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3 | // |
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4 | // The contents of this file are covered under the licence agreement in the |
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5 | // file "LICENCE" distributed with Cforall. |
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6 | // |
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7 | // monitor_desc.c -- |
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8 | // |
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9 | // Author : Thierry Delisle |
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10 | // Created On : Thd Feb 23 12:27:26 2017 |
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11 | // Last Modified By : Peter A. Buhr |
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12 | // Last Modified On : Mon Jul 31 14:59:05 2017 |
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13 | // Update Count : 3 |
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14 | // |
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15 | |
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16 | #include "monitor" |
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17 | |
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18 | #include <stdlib> |
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19 | #include <inttypes.h> |
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20 | |
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21 | #include "libhdr.h" |
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22 | #include "kernel_private.h" |
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23 | |
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24 | #include "bits/algorithms.h" |
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25 | |
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26 | //----------------------------------------------------------------------------- |
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27 | // Forward declarations |
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28 | static inline void set_owner ( monitor_desc * this, thread_desc * owner ); |
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29 | static inline void set_owner ( monitor_desc * storage [], __lock_size_t count, thread_desc * owner ); |
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30 | static inline void set_mask ( monitor_desc * storage [], __lock_size_t count, const __waitfor_mask_t & mask ); |
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31 | static inline void reset_mask( monitor_desc * this ); |
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32 | |
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33 | static inline thread_desc * next_thread( monitor_desc * this ); |
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34 | static inline bool is_accepted( monitor_desc * this, const __monitor_group_t & monitors ); |
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35 | |
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36 | static inline void lock_all ( __spinlock_t * locks [], __lock_size_t count ); |
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37 | static inline void lock_all ( monitor_desc * source [], __spinlock_t * /*out*/ locks [], __lock_size_t count ); |
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38 | static inline void unlock_all( __spinlock_t * locks [], __lock_size_t count ); |
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39 | static inline void unlock_all( monitor_desc * locks [], __lock_size_t count ); |
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40 | |
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41 | static inline void save ( monitor_desc * ctx [], __lock_size_t count, __spinlock_t * locks [], unsigned int /*out*/ recursions [], __waitfor_mask_t /*out*/ masks [] ); |
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42 | static inline void restore( monitor_desc * ctx [], __lock_size_t count, __spinlock_t * locks [], unsigned int /*in */ recursions [], __waitfor_mask_t /*in */ masks [] ); |
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43 | |
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44 | static inline void init ( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] ); |
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45 | static inline void init_push( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] ); |
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46 | |
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47 | static inline thread_desc * check_condition ( __condition_criterion_t * ); |
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48 | static inline void brand_condition ( condition & ); |
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49 | static inline [thread_desc *, int] search_entry_queue( const __waitfor_mask_t &, monitor_desc * monitors [], __lock_size_t count ); |
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50 | |
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51 | forall(dtype T | sized( T )) |
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52 | static inline __lock_size_t insert_unique( T * array [], __lock_size_t & size, T * val ); |
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53 | static inline __lock_size_t count_max ( const __waitfor_mask_t & mask ); |
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54 | static inline __lock_size_t aggregate ( monitor_desc * storage [], const __waitfor_mask_t & mask ); |
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55 | |
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56 | #ifndef __CFA_LOCK_NO_YIELD |
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57 | #define DO_LOCK lock_yield |
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58 | #else |
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59 | #define DO_LOCK lock |
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60 | #endif |
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61 | |
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62 | //----------------------------------------------------------------------------- |
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63 | // Useful defines |
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64 | #define wait_ctx(thrd, user_info) /* Create the necessary information to use the signaller stack */ \ |
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65 | __condition_node_t waiter = { thrd, count, user_info }; /* Create the node specific to this wait operation */ \ |
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66 | __condition_criterion_t criteria[count]; /* Create the creteria this wait operation needs to wake up */ \ |
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67 | init( count, monitors, waiter, criteria ); /* Link everything together */ \ |
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68 | |
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69 | #define wait_ctx_primed(thrd, user_info) /* Create the necessary information to use the signaller stack */ \ |
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70 | __condition_node_t waiter = { thrd, count, user_info }; /* Create the node specific to this wait operation */ \ |
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71 | __condition_criterion_t criteria[count]; /* Create the creteria this wait operation needs to wake up */ \ |
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72 | init_push( count, monitors, waiter, criteria ); /* Link everything together and push it to the AS-Stack */ \ |
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73 | |
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74 | #define monitor_ctx( mons, cnt ) /* Define that create the necessary struct for internal/external scheduling operations */ \ |
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75 | monitor_desc ** monitors = mons; /* Save the targeted monitors */ \ |
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76 | __lock_size_t count = cnt; /* Save the count to a local variable */ \ |
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77 | unsigned int recursions[ count ]; /* Save the current recursion levels to restore them later */ \ |
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78 | __waitfor_mask_t masks [ count ]; /* Save the current waitfor masks to restore them later */ \ |
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79 | __spinlock_t * locks [ count ]; /* We need to pass-in an array of locks to BlockInternal */ \ |
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80 | |
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81 | #define monitor_save save ( monitors, count, locks, recursions, masks ) |
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82 | #define monitor_restore restore( monitors, count, locks, recursions, masks ) |
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83 | |
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84 | |
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85 | //----------------------------------------------------------------------------- |
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86 | // Enter/Leave routines |
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87 | |
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88 | |
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89 | extern "C" { |
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90 | // Enter single monitor |
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91 | static void __enter_monitor_desc( monitor_desc * this, const __monitor_group_t & group ) { |
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92 | // Lock the monitor spinlock |
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93 | DO_LOCK( this->lock DEBUG_CTX2 ); |
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94 | thread_desc * thrd = this_thread; |
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95 | |
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96 | LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entering mon %p (%p)\n", thrd, this, this->owner); |
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97 | |
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98 | if( !this->owner ) { |
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99 | // No one has the monitor, just take it |
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100 | set_owner( this, thrd ); |
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101 | |
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102 | LIB_DEBUG_PRINT_SAFE("Kernel : mon is free \n"); |
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103 | } |
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104 | else if( this->owner == thrd) { |
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105 | // We already have the monitor, just note how many times we took it |
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106 | this->recursion += 1; |
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107 | |
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108 | LIB_DEBUG_PRINT_SAFE("Kernel : mon already owned \n"); |
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109 | } |
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110 | else if( is_accepted( this, group) ) { |
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111 | // Some one was waiting for us, enter |
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112 | set_owner( this, thrd ); |
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113 | |
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114 | // Reset mask |
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115 | reset_mask( this ); |
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116 | |
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117 | LIB_DEBUG_PRINT_SAFE("Kernel : mon accepts \n"); |
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118 | } |
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119 | else { |
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120 | LIB_DEBUG_PRINT_SAFE("Kernel : blocking \n"); |
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121 | |
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122 | // Some one else has the monitor, wait in line for it |
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123 | append( this->entry_queue, thrd ); |
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124 | BlockInternal( &this->lock ); |
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125 | |
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126 | LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entered mon %p\n", thrd, this); |
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127 | |
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128 | // BlockInternal will unlock spinlock, no need to unlock ourselves |
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129 | return; |
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130 | } |
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131 | |
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132 | LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entered mon %p\n", thrd, this); |
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133 | |
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134 | // Release the lock and leave |
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135 | unlock( this->lock ); |
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136 | return; |
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137 | } |
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138 | |
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139 | static void __enter_monitor_dtor( monitor_desc * this, fptr_t func ) { |
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140 | // Lock the monitor spinlock |
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141 | DO_LOCK( this->lock DEBUG_CTX2 ); |
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142 | thread_desc * thrd = this_thread; |
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143 | |
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144 | LIB_DEBUG_PRINT_SAFE("Kernel : %10p Entering dtor for mon %p (%p)\n", thrd, this, this->owner); |
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145 | |
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146 | |
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147 | if( !this->owner ) { |
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148 | LIB_DEBUG_PRINT_SAFE("Kernel : Destroying free mon %p\n", this); |
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149 | |
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150 | // No one has the monitor, just take it |
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151 | set_owner( this, thrd ); |
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152 | |
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153 | unlock( this->lock ); |
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154 | return; |
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155 | } |
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156 | else if( this->owner == thrd) { |
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157 | // We already have the monitor... but where about to destroy it so the nesting will fail |
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158 | // Abort! |
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159 | abortf("Attempt to destroy monitor %p by thread \"%.256s\" (%p) in nested mutex."); |
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160 | } |
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161 | |
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162 | __lock_size_t count = 1; |
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163 | monitor_desc ** monitors = &this; |
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164 | __monitor_group_t group = { &this, 1, func }; |
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165 | if( is_accepted( this, group) ) { |
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166 | LIB_DEBUG_PRINT_SAFE("Kernel : mon accepts dtor, block and signal it \n"); |
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167 | |
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168 | // Wake the thread that is waiting for this |
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169 | __condition_criterion_t * urgent = pop( this->signal_stack ); |
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170 | verify( urgent ); |
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171 | |
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172 | // Reset mask |
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173 | reset_mask( this ); |
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174 | |
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175 | // Create the node specific to this wait operation |
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176 | wait_ctx_primed( this_thread, 0 ) |
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177 | |
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178 | // Some one else has the monitor, wait for him to finish and then run |
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179 | BlockInternal( &this->lock, urgent->owner->waiting_thread ); |
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180 | |
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181 | // Some one was waiting for us, enter |
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182 | set_owner( this, thrd ); |
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183 | } |
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184 | else { |
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185 | LIB_DEBUG_PRINT_SAFE("Kernel : blocking \n"); |
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186 | |
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187 | wait_ctx( this_thread, 0 ) |
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188 | this->dtor_node = &waiter; |
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189 | |
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190 | // Some one else has the monitor, wait in line for it |
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191 | append( this->entry_queue, thrd ); |
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192 | BlockInternal( &this->lock ); |
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193 | |
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194 | // BlockInternal will unlock spinlock, no need to unlock ourselves |
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195 | return; |
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196 | } |
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197 | |
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198 | LIB_DEBUG_PRINT_SAFE("Kernel : Destroying %p\n", this); |
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199 | |
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200 | } |
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201 | |
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202 | // Leave single monitor |
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203 | void __leave_monitor_desc( monitor_desc * this ) { |
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204 | // Lock the monitor spinlock, DO_LOCK to reduce contention |
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205 | DO_LOCK( this->lock DEBUG_CTX2 ); |
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206 | |
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207 | LIB_DEBUG_PRINT_SAFE("Kernel : %10p Leaving mon %p (%p)\n", this_thread, this, this->owner); |
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208 | |
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209 | verifyf( this_thread == this->owner, "Expected owner to be %p, got %p (r: %i, m: %p)", this_thread, this->owner, this->recursion, this ); |
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210 | |
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211 | // Leaving a recursion level, decrement the counter |
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212 | this->recursion -= 1; |
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213 | |
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214 | // If we haven't left the last level of recursion |
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215 | // it means we don't need to do anything |
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216 | if( this->recursion != 0) { |
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217 | LIB_DEBUG_PRINT_SAFE("Kernel : recursion still %d\n", this->recursion); |
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218 | unlock( this->lock ); |
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219 | return; |
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220 | } |
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221 | |
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222 | // Get the next thread, will be null on low contention monitor |
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223 | thread_desc * new_owner = next_thread( this ); |
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224 | |
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225 | // We can now let other threads in safely |
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226 | unlock( this->lock ); |
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227 | |
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228 | //We need to wake-up the thread |
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229 | WakeThread( new_owner ); |
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230 | } |
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231 | |
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232 | // Leave single monitor for the last time |
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233 | void __leave_dtor_monitor_desc( monitor_desc * this ) { |
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234 | LIB_DEBUG_DO( |
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235 | if( this_thread != this->owner ) { |
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236 | abortf("Destroyed monitor %p has inconsistent owner, expected %p got %p.\n", this, this_thread, this->owner); |
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237 | } |
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238 | if( this->recursion != 1 ) { |
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239 | abortf("Destroyed monitor %p has %d outstanding nested calls.\n", this, this->recursion - 1); |
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240 | } |
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241 | ) |
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242 | } |
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243 | |
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244 | // Leave the thread monitor |
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245 | // last routine called by a thread. |
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246 | // Should never return |
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247 | void __leave_thread_monitor( thread_desc * thrd ) { |
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248 | monitor_desc * this = &thrd->self_mon; |
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249 | |
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250 | // Lock the monitor now |
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251 | DO_LOCK( this->lock DEBUG_CTX2 ); |
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252 | |
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253 | disable_interrupts(); |
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254 | |
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255 | thrd->self_cor.state = Halted; |
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256 | |
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257 | verifyf( thrd == this->owner, "Expected owner to be %p, got %p (r: %i, m: %p)", thrd, this->owner, this->recursion, this ); |
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258 | |
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259 | // Leaving a recursion level, decrement the counter |
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260 | this->recursion -= 1; |
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261 | |
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262 | // If we haven't left the last level of recursion |
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263 | // it must mean there is an error |
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264 | if( this->recursion != 0) { abortf("Thread internal monitor has unbalanced recursion"); } |
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265 | |
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266 | // Fetch the next thread, can be null |
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267 | thread_desc * new_owner = next_thread( this ); |
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268 | |
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269 | // Leave the thread, this will unlock the spinlock |
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270 | // Use leave thread instead of BlockInternal which is |
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271 | // specialized for this case and supports null new_owner |
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272 | LeaveThread( &this->lock, new_owner ); |
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273 | |
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274 | // Control flow should never reach here! |
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275 | } |
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276 | } |
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277 | |
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278 | // Enter multiple monitor |
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279 | // relies on the monitor array being sorted |
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280 | static inline void enter( __monitor_group_t monitors ) { |
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281 | for( __lock_size_t i = 0; i < monitors.size; i++) { |
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282 | __enter_monitor_desc( monitors.list[i], monitors ); |
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283 | } |
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284 | } |
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285 | |
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286 | // Leave multiple monitor |
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287 | // relies on the monitor array being sorted |
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288 | static inline void leave(monitor_desc * monitors [], __lock_size_t count) { |
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289 | for( __lock_size_t i = count - 1; i >= 0; i--) { |
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290 | __leave_monitor_desc( monitors[i] ); |
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291 | } |
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292 | } |
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293 | |
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294 | // Ctor for monitor guard |
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295 | // Sorts monitors before entering |
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296 | void ?{}( monitor_guard_t & this, monitor_desc * m [], __lock_size_t count, fptr_t func ) { |
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297 | // Store current array |
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298 | this.m = m; |
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299 | this.count = count; |
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300 | |
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301 | // Sort monitors based on address -> TODO use a sort specialized for small numbers |
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302 | __libcfa_small_sort(this.m, count); |
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303 | |
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304 | // Save previous thread context |
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305 | this.[prev_mntrs, prev_count, prev_func] = this_thread->monitors.[list, size, func]; |
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306 | |
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307 | // Update thread context (needed for conditions) |
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308 | this_thread->monitors.[list, size, func] = [m, count, func]; |
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309 | |
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310 | // LIB_DEBUG_PRINT_SAFE("MGUARD : enter %d\n", count); |
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311 | |
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312 | // Enter the monitors in order |
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313 | __monitor_group_t group = {this.m, this.count, func}; |
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314 | enter( group ); |
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315 | |
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316 | // LIB_DEBUG_PRINT_SAFE("MGUARD : entered\n"); |
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317 | } |
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318 | |
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319 | |
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320 | // Dtor for monitor guard |
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321 | void ^?{}( monitor_guard_t & this ) { |
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322 | // LIB_DEBUG_PRINT_SAFE("MGUARD : leaving %d\n", this.count); |
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323 | |
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324 | // Leave the monitors in order |
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325 | leave( this.m, this.count ); |
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326 | |
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327 | // LIB_DEBUG_PRINT_SAFE("MGUARD : left\n"); |
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328 | |
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329 | // Restore thread context |
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330 | this_thread->monitors.[list, size, func] = this.[prev_mntrs, prev_count, prev_func]; |
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331 | } |
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332 | |
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333 | // Ctor for monitor guard |
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334 | // Sorts monitors before entering |
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335 | void ?{}( monitor_dtor_guard_t & this, monitor_desc * m [], fptr_t func ) { |
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336 | // Store current array |
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337 | this.m = *m; |
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338 | |
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339 | // Save previous thread context |
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340 | this.[prev_mntrs, prev_count, prev_func] = this_thread->monitors.[list, size, func]; |
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341 | |
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342 | // Update thread context (needed for conditions) |
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343 | this_thread->monitors.[list, size, func] = [m, 1, func]; |
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344 | |
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345 | __enter_monitor_dtor( this.m, func ); |
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346 | } |
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347 | |
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348 | // Dtor for monitor guard |
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349 | void ^?{}( monitor_dtor_guard_t & this ) { |
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350 | // Leave the monitors in order |
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351 | __leave_dtor_monitor_desc( this.m ); |
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352 | |
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353 | // Restore thread context |
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354 | this_thread->monitors.[list, size, func] = this.[prev_mntrs, prev_count, prev_func]; |
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355 | } |
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356 | |
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357 | //----------------------------------------------------------------------------- |
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358 | // Internal scheduling types |
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359 | void ?{}(__condition_node_t & this, thread_desc * waiting_thread, __lock_size_t count, uintptr_t user_info ) { |
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360 | this.waiting_thread = waiting_thread; |
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361 | this.count = count; |
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362 | this.next = NULL; |
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363 | this.user_info = user_info; |
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364 | } |
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365 | |
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366 | void ?{}(__condition_criterion_t & this ) { |
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367 | this.ready = false; |
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368 | this.target = NULL; |
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369 | this.owner = NULL; |
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370 | this.next = NULL; |
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371 | } |
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372 | |
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373 | void ?{}(__condition_criterion_t & this, monitor_desc * target, __condition_node_t & owner ) { |
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374 | this.ready = false; |
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375 | this.target = target; |
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376 | this.owner = &owner; |
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377 | this.next = NULL; |
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378 | } |
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379 | |
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380 | //----------------------------------------------------------------------------- |
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381 | // Internal scheduling |
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382 | void wait( condition & this, uintptr_t user_info = 0 ) { |
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383 | brand_condition( this ); |
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384 | |
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385 | // Check that everything is as expected |
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386 | assertf( this.monitors != NULL, "Waiting with no monitors (%p)", this.monitors ); |
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387 | verifyf( this.monitor_count != 0, "Waiting with 0 monitors (%"PRIiFAST16")", this.monitor_count ); |
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388 | verifyf( this.monitor_count < 32u, "Excessive monitor count (%"PRIiFAST16")", this.monitor_count ); |
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389 | |
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390 | // Create storage for monitor context |
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391 | monitor_ctx( this.monitors, this.monitor_count ); |
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392 | |
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393 | // Create the node specific to this wait operation |
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394 | wait_ctx( this_thread, user_info ); |
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395 | |
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396 | // Append the current wait operation to the ones already queued on the condition |
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397 | // We don't need locks for that since conditions must always be waited on inside monitor mutual exclusion |
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398 | append( this.blocked, &waiter ); |
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399 | |
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400 | // Lock all monitors (aggregates the locks as well) |
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401 | lock_all( monitors, locks, count ); |
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402 | |
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403 | // Find the next thread(s) to run |
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404 | __lock_size_t thread_count = 0; |
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405 | thread_desc * threads[ count ]; |
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406 | __builtin_memset( threads, 0, sizeof( threads ) ); |
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407 | |
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408 | // Save monitor states |
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409 | monitor_save; |
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410 | |
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411 | // Remove any duplicate threads |
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412 | for( __lock_size_t i = 0; i < count; i++) { |
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413 | thread_desc * new_owner = next_thread( monitors[i] ); |
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414 | insert_unique( threads, thread_count, new_owner ); |
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415 | } |
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416 | |
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417 | // Everything is ready to go to sleep |
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418 | BlockInternal( locks, count, threads, thread_count ); |
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419 | |
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420 | // We are back, restore the owners and recursions |
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421 | monitor_restore; |
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422 | } |
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423 | |
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424 | bool signal( condition & this ) { |
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425 | if( is_empty( this ) ) { return false; } |
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426 | |
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427 | //Check that everything is as expected |
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428 | verify( this.monitors ); |
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429 | verify( this.monitor_count != 0 ); |
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430 | |
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431 | //Some more checking in debug |
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432 | LIB_DEBUG_DO( |
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433 | thread_desc * this_thrd = this_thread; |
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434 | if ( this.monitor_count != this_thrd->monitors.size ) { |
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435 | abortf( "Signal on condition %p made with different number of monitor(s), expected %i got %i", &this, this.monitor_count, this_thrd->monitors.size ); |
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436 | } |
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437 | |
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438 | for(int i = 0; i < this.monitor_count; i++) { |
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439 | if ( this.monitors[i] != this_thrd->monitors.list[i] ) { |
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440 | abortf( "Signal on condition %p made with different monitor, expected %p got %i", &this, this.monitors[i], this_thrd->monitors.list[i] ); |
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441 | } |
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442 | } |
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443 | ); |
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444 | |
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445 | __lock_size_t count = this.monitor_count; |
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446 | |
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447 | // Lock all monitors |
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448 | lock_all( this.monitors, NULL, count ); |
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449 | |
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450 | //Pop the head of the waiting queue |
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451 | __condition_node_t * node = pop_head( this.blocked ); |
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452 | |
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453 | //Add the thread to the proper AS stack |
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454 | for(int i = 0; i < count; i++) { |
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455 | __condition_criterion_t * crit = &node->criteria[i]; |
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456 | assert( !crit->ready ); |
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457 | push( crit->target->signal_stack, crit ); |
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458 | } |
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459 | |
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460 | //Release |
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461 | unlock_all( this.monitors, count ); |
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462 | |
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463 | return true; |
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464 | } |
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465 | |
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466 | bool signal_block( condition & this ) { |
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467 | if( !this.blocked.head ) { return false; } |
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468 | |
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469 | //Check that everything is as expected |
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470 | verifyf( this.monitors != NULL, "Waiting with no monitors (%p)", this.monitors ); |
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471 | verifyf( this.monitor_count != 0, "Waiting with 0 monitors (%"PRIiFAST16")", this.monitor_count ); |
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472 | |
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473 | // Create storage for monitor context |
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474 | monitor_ctx( this.monitors, this.monitor_count ); |
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475 | |
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476 | // Lock all monitors (aggregates the locks them as well) |
---|
477 | lock_all( monitors, locks, count ); |
---|
478 | |
---|
479 | // Create the node specific to this wait operation |
---|
480 | wait_ctx_primed( this_thread, 0 ) |
---|
481 | |
---|
482 | //save contexts |
---|
483 | monitor_save; |
---|
484 | |
---|
485 | //Find the thread to run |
---|
486 | thread_desc * signallee = pop_head( this.blocked )->waiting_thread; |
---|
487 | set_owner( monitors, count, signallee ); |
---|
488 | |
---|
489 | LIB_DEBUG_PRINT_BUFFER_DECL( "Kernel : signal_block condition %p (s: %p)\n", &this, signallee ); |
---|
490 | |
---|
491 | //Everything is ready to go to sleep |
---|
492 | BlockInternal( locks, count, &signallee, 1 ); |
---|
493 | |
---|
494 | |
---|
495 | // WE WOKE UP |
---|
496 | |
---|
497 | |
---|
498 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : signal_block returned\n" ); |
---|
499 | |
---|
500 | //We are back, restore the masks and recursions |
---|
501 | monitor_restore; |
---|
502 | |
---|
503 | return true; |
---|
504 | } |
---|
505 | |
---|
506 | // Access the user_info of the thread waiting at the front of the queue |
---|
507 | uintptr_t front( condition & this ) { |
---|
508 | verifyf( !is_empty(this), |
---|
509 | "Attempt to access user data on an empty condition.\n" |
---|
510 | "Possible cause is not checking if the condition is empty before reading stored data." |
---|
511 | ); |
---|
512 | return this.blocked.head->user_info; |
---|
513 | } |
---|
514 | |
---|
515 | //----------------------------------------------------------------------------- |
---|
516 | // External scheduling |
---|
517 | // cases to handle : |
---|
518 | // - target already there : |
---|
519 | // block and wake |
---|
520 | // - dtor already there |
---|
521 | // put thread on signaller stack |
---|
522 | // - non-blocking |
---|
523 | // return else |
---|
524 | // - timeout |
---|
525 | // return timeout |
---|
526 | // - block |
---|
527 | // setup mask |
---|
528 | // block |
---|
529 | void __waitfor_internal( const __waitfor_mask_t & mask, int duration ) { |
---|
530 | // This statment doesn't have a contiguous list of monitors... |
---|
531 | // Create one! |
---|
532 | __lock_size_t max = count_max( mask ); |
---|
533 | monitor_desc * mon_storage[max]; |
---|
534 | __builtin_memset( mon_storage, 0, sizeof( mon_storage ) ); |
---|
535 | __lock_size_t actual_count = aggregate( mon_storage, mask ); |
---|
536 | |
---|
537 | LIB_DEBUG_PRINT_BUFFER_DECL( "Kernel : waitfor %d (s: %d, m: %d)\n", actual_count, mask.size, (__lock_size_t)max); |
---|
538 | |
---|
539 | if(actual_count == 0) return; |
---|
540 | |
---|
541 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : waitfor internal proceeding\n"); |
---|
542 | |
---|
543 | // Create storage for monitor context |
---|
544 | monitor_ctx( mon_storage, actual_count ); |
---|
545 | |
---|
546 | // Lock all monitors (aggregates the locks as well) |
---|
547 | lock_all( monitors, locks, count ); |
---|
548 | |
---|
549 | { |
---|
550 | // Check if the entry queue |
---|
551 | thread_desc * next; int index; |
---|
552 | [next, index] = search_entry_queue( mask, monitors, count ); |
---|
553 | |
---|
554 | if( next ) { |
---|
555 | *mask.accepted = index; |
---|
556 | if( mask.clauses[index].is_dtor ) { |
---|
557 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : dtor already there\n"); |
---|
558 | verifyf( mask.clauses[index].size == 1 , "ERROR: Accepted dtor has more than 1 mutex parameter." ); |
---|
559 | |
---|
560 | monitor_desc * mon2dtor = mask.clauses[index].list[0]; |
---|
561 | verifyf( mon2dtor->dtor_node, "ERROR: Accepted monitor has no dtor_node." ); |
---|
562 | |
---|
563 | __condition_criterion_t * dtor_crit = mon2dtor->dtor_node->criteria; |
---|
564 | push( mon2dtor->signal_stack, dtor_crit ); |
---|
565 | |
---|
566 | unlock_all( locks, count ); |
---|
567 | } |
---|
568 | else { |
---|
569 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : thread present, baton-passing\n"); |
---|
570 | |
---|
571 | // Create the node specific to this wait operation |
---|
572 | wait_ctx_primed( this_thread, 0 ); |
---|
573 | |
---|
574 | // Save monitor states |
---|
575 | monitor_save; |
---|
576 | |
---|
577 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : baton of %d monitors : ", count ); |
---|
578 | #ifdef __CFA_DEBUG_PRINT__ |
---|
579 | for( int i = 0; i < count; i++) { |
---|
580 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "%p %p ", monitors[i], monitors[i]->signal_stack.top ); |
---|
581 | } |
---|
582 | #endif |
---|
583 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "\n"); |
---|
584 | |
---|
585 | // Set the owners to be the next thread |
---|
586 | set_owner( monitors, count, next ); |
---|
587 | |
---|
588 | // Everything is ready to go to sleep |
---|
589 | BlockInternal( locks, count, &next, 1 ); |
---|
590 | |
---|
591 | // We are back, restore the owners and recursions |
---|
592 | monitor_restore; |
---|
593 | |
---|
594 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : thread present, returned\n"); |
---|
595 | } |
---|
596 | |
---|
597 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : accepted %d\n", *mask.accepted); |
---|
598 | |
---|
599 | return; |
---|
600 | } |
---|
601 | } |
---|
602 | |
---|
603 | |
---|
604 | if( duration == 0 ) { |
---|
605 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : non-blocking, exiting\n"); |
---|
606 | |
---|
607 | unlock_all( locks, count ); |
---|
608 | |
---|
609 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : accepted %d\n", *mask.accepted); |
---|
610 | return; |
---|
611 | } |
---|
612 | |
---|
613 | |
---|
614 | verifyf( duration < 0, "Timeout on waitfor statments not supported yet."); |
---|
615 | |
---|
616 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : blocking waitfor\n"); |
---|
617 | |
---|
618 | // Create the node specific to this wait operation |
---|
619 | wait_ctx_primed( this_thread, 0 ); |
---|
620 | |
---|
621 | monitor_save; |
---|
622 | set_mask( monitors, count, mask ); |
---|
623 | |
---|
624 | for( __lock_size_t i = 0; i < count; i++) { |
---|
625 | verify( monitors[i]->owner == this_thread ); |
---|
626 | } |
---|
627 | |
---|
628 | //Everything is ready to go to sleep |
---|
629 | BlockInternal( locks, count ); |
---|
630 | |
---|
631 | |
---|
632 | // WE WOKE UP |
---|
633 | |
---|
634 | |
---|
635 | //We are back, restore the masks and recursions |
---|
636 | monitor_restore; |
---|
637 | |
---|
638 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : exiting\n"); |
---|
639 | |
---|
640 | LIB_DEBUG_PRINT_BUFFER_LOCAL( "Kernel : accepted %d\n", *mask.accepted); |
---|
641 | } |
---|
642 | |
---|
643 | //----------------------------------------------------------------------------- |
---|
644 | // Utilities |
---|
645 | |
---|
646 | static inline void set_owner( monitor_desc * this, thread_desc * owner ) { |
---|
647 | // LIB_DEBUG_PRINT_SAFE("Kernal : Setting owner of %p to %p ( was %p)\n", this, owner, this->owner ); |
---|
648 | |
---|
649 | //Pass the monitor appropriately |
---|
650 | this->owner = owner; |
---|
651 | |
---|
652 | //We are passing the monitor to someone else, which means recursion level is not 0 |
---|
653 | this->recursion = owner ? 1 : 0; |
---|
654 | } |
---|
655 | |
---|
656 | static inline void set_owner( monitor_desc * monitors [], __lock_size_t count, thread_desc * owner ) { |
---|
657 | monitors[0]->owner = owner; |
---|
658 | monitors[0]->recursion = 1; |
---|
659 | for( __lock_size_t i = 1; i < count; i++ ) { |
---|
660 | monitors[i]->owner = owner; |
---|
661 | monitors[i]->recursion = 0; |
---|
662 | } |
---|
663 | } |
---|
664 | |
---|
665 | static inline void set_mask( monitor_desc * storage [], __lock_size_t count, const __waitfor_mask_t & mask ) { |
---|
666 | for( __lock_size_t i = 0; i < count; i++) { |
---|
667 | storage[i]->mask = mask; |
---|
668 | } |
---|
669 | } |
---|
670 | |
---|
671 | static inline void reset_mask( monitor_desc * this ) { |
---|
672 | this->mask.accepted = NULL; |
---|
673 | this->mask.clauses = NULL; |
---|
674 | this->mask.size = 0; |
---|
675 | } |
---|
676 | |
---|
677 | static inline thread_desc * next_thread( monitor_desc * this ) { |
---|
678 | //Check the signaller stack |
---|
679 | LIB_DEBUG_PRINT_SAFE("Kernel : mon %p AS-stack top %p\n", this, this->signal_stack.top); |
---|
680 | __condition_criterion_t * urgent = pop( this->signal_stack ); |
---|
681 | if( urgent ) { |
---|
682 | //The signaller stack is not empty, |
---|
683 | //regardless of if we are ready to baton pass, |
---|
684 | //we need to set the monitor as in use |
---|
685 | set_owner( this, urgent->owner->waiting_thread ); |
---|
686 | |
---|
687 | return check_condition( urgent ); |
---|
688 | } |
---|
689 | |
---|
690 | // No signaller thread |
---|
691 | // Get the next thread in the entry_queue |
---|
692 | thread_desc * new_owner = pop_head( this->entry_queue ); |
---|
693 | set_owner( this, new_owner ); |
---|
694 | |
---|
695 | return new_owner; |
---|
696 | } |
---|
697 | |
---|
698 | static inline bool is_accepted( monitor_desc * this, const __monitor_group_t & group ) { |
---|
699 | __acceptable_t * it = this->mask.clauses; // Optim |
---|
700 | __lock_size_t count = this->mask.size; |
---|
701 | |
---|
702 | // Check if there are any acceptable functions |
---|
703 | if( !it ) return false; |
---|
704 | |
---|
705 | // If this isn't the first monitor to test this, there is no reason to repeat the test. |
---|
706 | if( this != group[0] ) return group[0]->mask.accepted >= 0; |
---|
707 | |
---|
708 | // For all acceptable functions check if this is the current function. |
---|
709 | for( __lock_size_t i = 0; i < count; i++, it++ ) { |
---|
710 | if( *it == group ) { |
---|
711 | *this->mask.accepted = i; |
---|
712 | return true; |
---|
713 | } |
---|
714 | } |
---|
715 | |
---|
716 | // No function matched |
---|
717 | return false; |
---|
718 | } |
---|
719 | |
---|
720 | static inline void init( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] ) { |
---|
721 | for( __lock_size_t i = 0; i < count; i++) { |
---|
722 | (criteria[i]){ monitors[i], waiter }; |
---|
723 | } |
---|
724 | |
---|
725 | waiter.criteria = criteria; |
---|
726 | } |
---|
727 | |
---|
728 | static inline void init_push( __lock_size_t count, monitor_desc * monitors [], __condition_node_t & waiter, __condition_criterion_t criteria [] ) { |
---|
729 | for( __lock_size_t i = 0; i < count; i++) { |
---|
730 | (criteria[i]){ monitors[i], waiter }; |
---|
731 | LIB_DEBUG_PRINT_SAFE( "Kernel : target %p = %p\n", criteria[i].target, &criteria[i] ); |
---|
732 | push( criteria[i].target->signal_stack, &criteria[i] ); |
---|
733 | } |
---|
734 | |
---|
735 | waiter.criteria = criteria; |
---|
736 | } |
---|
737 | |
---|
738 | static inline void lock_all( __spinlock_t * locks [], __lock_size_t count ) { |
---|
739 | for( __lock_size_t i = 0; i < count; i++ ) { |
---|
740 | DO_LOCK( *locks[i] DEBUG_CTX2 ); |
---|
741 | } |
---|
742 | } |
---|
743 | |
---|
744 | static inline void lock_all( monitor_desc * source [], __spinlock_t * /*out*/ locks [], __lock_size_t count ) { |
---|
745 | for( __lock_size_t i = 0; i < count; i++ ) { |
---|
746 | __spinlock_t * l = &source[i]->lock; |
---|
747 | DO_LOCK( *l DEBUG_CTX2 ); |
---|
748 | if(locks) locks[i] = l; |
---|
749 | } |
---|
750 | } |
---|
751 | |
---|
752 | static inline void unlock_all( __spinlock_t * locks [], __lock_size_t count ) { |
---|
753 | for( __lock_size_t i = 0; i < count; i++ ) { |
---|
754 | unlock( *locks[i] ); |
---|
755 | } |
---|
756 | } |
---|
757 | |
---|
758 | static inline void unlock_all( monitor_desc * locks [], __lock_size_t count ) { |
---|
759 | for( __lock_size_t i = 0; i < count; i++ ) { |
---|
760 | unlock( locks[i]->lock ); |
---|
761 | } |
---|
762 | } |
---|
763 | |
---|
764 | static inline void save( |
---|
765 | monitor_desc * ctx [], |
---|
766 | __lock_size_t count, |
---|
767 | __attribute((unused)) __spinlock_t * locks [], |
---|
768 | unsigned int /*out*/ recursions [], |
---|
769 | __waitfor_mask_t /*out*/ masks [] |
---|
770 | ) { |
---|
771 | for( __lock_size_t i = 0; i < count; i++ ) { |
---|
772 | recursions[i] = ctx[i]->recursion; |
---|
773 | masks[i] = ctx[i]->mask; |
---|
774 | } |
---|
775 | } |
---|
776 | |
---|
777 | static inline void restore( |
---|
778 | monitor_desc * ctx [], |
---|
779 | __lock_size_t count, |
---|
780 | __spinlock_t * locks [], |
---|
781 | unsigned int /*out*/ recursions [], |
---|
782 | __waitfor_mask_t /*out*/ masks [] |
---|
783 | ) { |
---|
784 | lock_all( locks, count ); |
---|
785 | for( __lock_size_t i = 0; i < count; i++ ) { |
---|
786 | ctx[i]->recursion = recursions[i]; |
---|
787 | ctx[i]->mask = masks[i]; |
---|
788 | } |
---|
789 | unlock_all( locks, count ); |
---|
790 | } |
---|
791 | |
---|
792 | // Function has 2 different behavior |
---|
793 | // 1 - Marks a monitors as being ready to run |
---|
794 | // 2 - Checks if all the monitors are ready to run |
---|
795 | // if so return the thread to run |
---|
796 | static inline thread_desc * check_condition( __condition_criterion_t * target ) { |
---|
797 | __condition_node_t * node = target->owner; |
---|
798 | unsigned short count = node->count; |
---|
799 | __condition_criterion_t * criteria = node->criteria; |
---|
800 | |
---|
801 | bool ready2run = true; |
---|
802 | |
---|
803 | for( int i = 0; i < count; i++ ) { |
---|
804 | |
---|
805 | // LIB_DEBUG_PRINT_SAFE( "Checking %p for %p\n", &criteria[i], target ); |
---|
806 | if( &criteria[i] == target ) { |
---|
807 | criteria[i].ready = true; |
---|
808 | // LIB_DEBUG_PRINT_SAFE( "True\n" ); |
---|
809 | } |
---|
810 | |
---|
811 | ready2run = criteria[i].ready && ready2run; |
---|
812 | } |
---|
813 | |
---|
814 | LIB_DEBUG_PRINT_SAFE( "Kernel : Runing %i (%p)\n", ready2run, ready2run ? node->waiting_thread : NULL ); |
---|
815 | return ready2run ? node->waiting_thread : NULL; |
---|
816 | } |
---|
817 | |
---|
818 | static inline void brand_condition( condition & this ) { |
---|
819 | thread_desc * thrd = this_thread; |
---|
820 | if( !this.monitors ) { |
---|
821 | // LIB_DEBUG_PRINT_SAFE("Branding\n"); |
---|
822 | assertf( thrd->monitors.list != NULL, "No current monitor to brand condition %p", thrd->monitors.list ); |
---|
823 | this.monitor_count = thrd->monitors.size; |
---|
824 | |
---|
825 | this.monitors = malloc( this.monitor_count * sizeof( *this.monitors ) ); |
---|
826 | for( int i = 0; i < this.monitor_count; i++ ) { |
---|
827 | this.monitors[i] = thrd->monitors.list[i]; |
---|
828 | } |
---|
829 | } |
---|
830 | } |
---|
831 | |
---|
832 | static inline [thread_desc *, int] search_entry_queue( const __waitfor_mask_t & mask, monitor_desc * monitors [], __lock_size_t count ) { |
---|
833 | |
---|
834 | __thread_queue_t & entry_queue = monitors[0]->entry_queue; |
---|
835 | |
---|
836 | // For each thread in the entry-queue |
---|
837 | for( thread_desc ** thrd_it = &entry_queue.head; |
---|
838 | *thrd_it; |
---|
839 | thrd_it = &(*thrd_it)->next |
---|
840 | ) { |
---|
841 | // For each acceptable check if it matches |
---|
842 | int i = 0; |
---|
843 | __acceptable_t * end = mask.clauses + mask.size; |
---|
844 | for( __acceptable_t * it = mask.clauses; it != end; it++, i++ ) { |
---|
845 | // Check if we have a match |
---|
846 | if( *it == (*thrd_it)->monitors ) { |
---|
847 | |
---|
848 | // If we have a match return it |
---|
849 | // after removeing it from the entry queue |
---|
850 | return [remove( entry_queue, thrd_it ), i]; |
---|
851 | } |
---|
852 | } |
---|
853 | } |
---|
854 | |
---|
855 | return [0, -1]; |
---|
856 | } |
---|
857 | |
---|
858 | forall(dtype T | sized( T )) |
---|
859 | static inline __lock_size_t insert_unique( T * array [], __lock_size_t & size, T * val ) { |
---|
860 | if( !val ) return size; |
---|
861 | |
---|
862 | for( __lock_size_t i = 0; i <= size; i++) { |
---|
863 | if( array[i] == val ) return size; |
---|
864 | } |
---|
865 | |
---|
866 | array[size] = val; |
---|
867 | size = size + 1; |
---|
868 | return size; |
---|
869 | } |
---|
870 | |
---|
871 | static inline __lock_size_t count_max( const __waitfor_mask_t & mask ) { |
---|
872 | __lock_size_t max = 0; |
---|
873 | for( __lock_size_t i = 0; i < mask.size; i++ ) { |
---|
874 | max += mask.clauses[i].size; |
---|
875 | } |
---|
876 | return max; |
---|
877 | } |
---|
878 | |
---|
879 | static inline __lock_size_t aggregate( monitor_desc * storage [], const __waitfor_mask_t & mask ) { |
---|
880 | __lock_size_t size = 0; |
---|
881 | for( __lock_size_t i = 0; i < mask.size; i++ ) { |
---|
882 | __libcfa_small_sort( mask.clauses[i].list, mask.clauses[i].size ); |
---|
883 | for( __lock_size_t j = 0; j < mask.clauses[i].size; j++) { |
---|
884 | insert_unique( storage, size, mask.clauses[i].list[j] ); |
---|
885 | } |
---|
886 | } |
---|
887 | // TODO insertion sort instead of this |
---|
888 | __libcfa_small_sort( storage, size ); |
---|
889 | return size; |
---|
890 | } |
---|
891 | |
---|
892 | void ?{}( __condition_blocked_queue_t & this ) { |
---|
893 | this.head = NULL; |
---|
894 | this.tail = &this.head; |
---|
895 | } |
---|
896 | |
---|
897 | void append( __condition_blocked_queue_t & this, __condition_node_t * c ) { |
---|
898 | verify(this.tail != NULL); |
---|
899 | *this.tail = c; |
---|
900 | this.tail = &c->next; |
---|
901 | } |
---|
902 | |
---|
903 | __condition_node_t * pop_head( __condition_blocked_queue_t & this ) { |
---|
904 | __condition_node_t * head = this.head; |
---|
905 | if( head ) { |
---|
906 | this.head = head->next; |
---|
907 | if( !head->next ) { |
---|
908 | this.tail = &this.head; |
---|
909 | } |
---|
910 | head->next = NULL; |
---|
911 | } |
---|
912 | return head; |
---|
913 | } |
---|
914 | |
---|
915 | // Local Variables: // |
---|
916 | // mode: c // |
---|
917 | // tab-width: 4 // |
---|
918 | // End: // |
---|