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