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 | // kernel.c -- |
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8 | // |
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9 | // Author : Thierry Delisle |
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10 | // Created On : Tue Jan 17 12:27:26 2017 |
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11 | // Last Modified By : Peter A. Buhr |
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12 | // Last Modified On : Tue Feb 4 13:03:15 2020 |
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13 | // Update Count : 58 |
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14 | // |
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15 | |
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16 | #define __cforall_thread__ |
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17 | // #define __CFA_DEBUG_PRINT_RUNTIME_CORE__ |
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18 | |
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19 | //C Includes |
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20 | #include <stddef.h> |
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21 | #include <errno.h> |
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22 | #include <string.h> |
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23 | extern "C" { |
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24 | #include <stdio.h> |
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25 | #include <fenv.h> |
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26 | #include <sys/resource.h> |
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27 | #include <signal.h> |
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28 | #include <unistd.h> |
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29 | #include <limits.h> // PTHREAD_STACK_MIN |
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30 | #include <sys/mman.h> // mprotect |
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31 | } |
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32 | |
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33 | //CFA Includes |
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34 | #include "time.hfa" |
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35 | #include "kernel_private.hfa" |
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36 | #include "preemption.hfa" |
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37 | #include "startup.hfa" |
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38 | |
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39 | //Private includes |
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40 | #define __CFA_INVOKE_PRIVATE__ |
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41 | #include "invoke.h" |
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42 | |
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43 | |
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44 | //----------------------------------------------------------------------------- |
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45 | // Some assembly required |
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46 | #if defined( __i386 ) |
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47 | #define CtxGet( ctx ) \ |
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48 | __asm__ volatile ( \ |
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49 | "movl %%esp,%0\n"\ |
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50 | "movl %%ebp,%1\n"\ |
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51 | : "=rm" (ctx.SP),\ |
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52 | "=rm" (ctx.FP) \ |
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53 | ) |
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54 | |
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55 | // mxcr : SSE Status and Control bits (control bits are preserved across function calls) |
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56 | // fcw : X87 FPU control word (preserved across function calls) |
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57 | #define __x87_store \ |
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58 | uint32_t __mxcr; \ |
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59 | uint16_t __fcw; \ |
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60 | __asm__ volatile ( \ |
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61 | "stmxcsr %0\n" \ |
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62 | "fnstcw %1\n" \ |
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63 | : "=m" (__mxcr),\ |
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64 | "=m" (__fcw) \ |
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65 | ) |
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66 | |
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67 | #define __x87_load \ |
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68 | __asm__ volatile ( \ |
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69 | "fldcw %1\n" \ |
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70 | "ldmxcsr %0\n" \ |
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71 | ::"m" (__mxcr),\ |
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72 | "m" (__fcw) \ |
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73 | ) |
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74 | |
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75 | #elif defined( __x86_64 ) |
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76 | #define CtxGet( ctx ) \ |
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77 | __asm__ volatile ( \ |
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78 | "movq %%rsp,%0\n"\ |
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79 | "movq %%rbp,%1\n"\ |
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80 | : "=rm" (ctx.SP),\ |
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81 | "=rm" (ctx.FP) \ |
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82 | ) |
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83 | |
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84 | #define __x87_store \ |
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85 | uint32_t __mxcr; \ |
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86 | uint16_t __fcw; \ |
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87 | __asm__ volatile ( \ |
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88 | "stmxcsr %0\n" \ |
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89 | "fnstcw %1\n" \ |
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90 | : "=m" (__mxcr),\ |
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91 | "=m" (__fcw) \ |
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92 | ) |
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93 | |
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94 | #define __x87_load \ |
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95 | __asm__ volatile ( \ |
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96 | "fldcw %1\n" \ |
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97 | "ldmxcsr %0\n" \ |
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98 | :: "m" (__mxcr),\ |
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99 | "m" (__fcw) \ |
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100 | ) |
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101 | |
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102 | |
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103 | #elif defined( __ARM_ARCH ) |
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104 | #define CtxGet( ctx ) __asm__ ( \ |
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105 | "mov %0,%%sp\n" \ |
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106 | "mov %1,%%r11\n" \ |
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107 | : "=rm" (ctx.SP), "=rm" (ctx.FP) ) |
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108 | #else |
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109 | #error unknown hardware architecture |
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110 | #endif |
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111 | |
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112 | //----------------------------------------------------------------------------- |
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113 | //Start and stop routine for the kernel, declared first to make sure they run first |
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114 | static void __kernel_startup (void) __attribute__(( constructor( STARTUP_PRIORITY_KERNEL ) )); |
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115 | static void __kernel_shutdown(void) __attribute__(( destructor ( STARTUP_PRIORITY_KERNEL ) )); |
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116 | |
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117 | //----------------------------------------------------------------------------- |
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118 | // Kernel Scheduling logic |
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119 | static $thread * __next_thread(cluster * this); |
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120 | static void __run_thread(processor * this, $thread * dst); |
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121 | static $thread * __halt(processor * this); |
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122 | static bool __wake_one(cluster * cltr); |
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123 | static bool __wake_proc(processor *); |
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124 | |
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125 | //----------------------------------------------------------------------------- |
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126 | // Kernel storage |
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127 | KERNEL_STORAGE(cluster, mainCluster); |
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128 | KERNEL_STORAGE(processor, mainProcessor); |
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129 | KERNEL_STORAGE($thread, mainThread); |
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130 | KERNEL_STORAGE(__stack_t, mainThreadCtx); |
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131 | |
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132 | cluster * mainCluster; |
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133 | processor * mainProcessor; |
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134 | $thread * mainThread; |
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135 | |
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136 | extern "C" { |
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137 | struct { __dllist_t(cluster) list; __spinlock_t lock; } __cfa_dbg_global_clusters; |
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138 | } |
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139 | |
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140 | size_t __page_size = 0; |
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141 | |
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142 | //----------------------------------------------------------------------------- |
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143 | // Global state |
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144 | thread_local struct KernelThreadData kernelTLS __attribute__ ((tls_model ( "initial-exec" ))) = { |
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145 | NULL, // cannot use 0p |
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146 | NULL, |
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147 | { 1, false, false }, |
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148 | 6u //this should be seeded better but due to a bug calling rdtsc doesn't work |
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149 | }; |
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150 | |
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151 | //----------------------------------------------------------------------------- |
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152 | // Struct to steal stack |
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153 | struct current_stack_info_t { |
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154 | __stack_t * storage; // pointer to stack object |
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155 | void * base; // base of stack |
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156 | void * limit; // stack grows towards stack limit |
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157 | void * context; // address of cfa_context_t |
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158 | }; |
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159 | |
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160 | void ?{}( current_stack_info_t & this ) { |
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161 | __stack_context_t ctx; |
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162 | CtxGet( ctx ); |
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163 | this.base = ctx.FP; |
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164 | |
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165 | rlimit r; |
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166 | getrlimit( RLIMIT_STACK, &r); |
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167 | size_t size = r.rlim_cur; |
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168 | |
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169 | this.limit = (void *)(((intptr_t)this.base) - size); |
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170 | this.context = &storage_mainThreadCtx; |
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171 | } |
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172 | |
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173 | //----------------------------------------------------------------------------- |
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174 | // Main thread construction |
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175 | |
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176 | void ?{}( $coroutine & this, current_stack_info_t * info) with( this ) { |
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177 | stack.storage = info->storage; |
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178 | with(*stack.storage) { |
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179 | limit = info->limit; |
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180 | base = info->base; |
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181 | } |
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182 | __attribute__((may_alias)) intptr_t * istorage = (intptr_t*) &stack.storage; |
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183 | *istorage |= 0x1; |
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184 | name = "Main Thread"; |
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185 | state = Start; |
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186 | starter = 0p; |
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187 | last = 0p; |
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188 | cancellation = 0p; |
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189 | } |
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190 | |
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191 | void ?{}( $thread & this, current_stack_info_t * info) with( this ) { |
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192 | state = Start; |
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193 | self_cor{ info }; |
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194 | curr_cor = &self_cor; |
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195 | curr_cluster = mainCluster; |
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196 | self_mon.owner = &this; |
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197 | self_mon.recursion = 1; |
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198 | self_mon_p = &self_mon; |
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199 | link.next = 0p; |
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200 | link.prev = 0p; |
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201 | |
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202 | node.next = 0p; |
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203 | node.prev = 0p; |
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204 | doregister(curr_cluster, this); |
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205 | |
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206 | monitors{ &self_mon_p, 1, (fptr_t)0 }; |
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207 | } |
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208 | |
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209 | //----------------------------------------------------------------------------- |
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210 | // Processor coroutine |
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211 | void ?{}(processorCtx_t & this) { |
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212 | |
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213 | } |
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214 | |
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215 | // Construct the processor context of non-main processors |
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216 | static void ?{}(processorCtx_t & this, processor * proc, current_stack_info_t * info) { |
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217 | (this.__cor){ info }; |
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218 | this.proc = proc; |
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219 | } |
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220 | |
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221 | static void * __invoke_processor(void * arg); |
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222 | |
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223 | void ?{}(processor & this, const char name[], cluster & cltr) with( this ) { |
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224 | this.name = name; |
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225 | this.cltr = &cltr; |
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226 | id = -1u; |
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227 | terminated{ 0 }; |
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228 | destroyer = 0p; |
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229 | do_terminate = false; |
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230 | preemption_alarm = 0p; |
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231 | pending_preemption = false; |
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232 | runner.proc = &this; |
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233 | |
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234 | idle{}; |
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235 | |
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236 | __cfadbg_print_safe(runtime_core, "Kernel : Starting core %p\n", &this); |
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237 | |
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238 | this.stack = __create_pthread( &this.kernel_thread, __invoke_processor, (void *)&this ); |
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239 | |
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240 | __cfadbg_print_safe(runtime_core, "Kernel : core %p created\n", &this); |
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241 | } |
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242 | |
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243 | void ^?{}(processor & this) with( this ){ |
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244 | if( ! __atomic_load_n(&do_terminate, __ATOMIC_ACQUIRE) ) { |
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245 | __cfadbg_print_safe(runtime_core, "Kernel : core %p signaling termination\n", &this); |
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246 | |
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247 | __atomic_store_n(&do_terminate, true, __ATOMIC_RELAXED); |
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248 | __wake_proc( &this ); |
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249 | |
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250 | P( terminated ); |
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251 | verify( kernelTLS.this_processor != &this); |
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252 | } |
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253 | |
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254 | int err = pthread_join( kernel_thread, 0p ); |
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255 | if( err != 0 ) abort("KERNEL ERROR: joining processor %p caused error %s\n", &this, strerror(err)); |
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256 | |
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257 | free( this.stack ); |
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258 | } |
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259 | |
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260 | void ?{}(cluster & this, const char name[], Duration preemption_rate, unsigned io_flags) with( this ) { |
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261 | this.name = name; |
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262 | this.preemption_rate = preemption_rate; |
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263 | ready_queue{}; |
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264 | ready_lock{}; |
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265 | |
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266 | #if !defined(__CFA_NO_STATISTICS__) |
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267 | print_stats = false; |
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268 | #endif |
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269 | |
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270 | procs{ __get }; |
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271 | idles{ __get }; |
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272 | threads{ __get }; |
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273 | |
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274 | __kernel_io_startup( this, io_flags, &this == mainCluster ); |
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275 | |
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276 | doregister(this); |
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277 | } |
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278 | |
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279 | void ^?{}(cluster & this) { |
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280 | __kernel_io_shutdown( this, &this == mainCluster ); |
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281 | |
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282 | unregister(this); |
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283 | } |
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284 | |
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285 | //============================================================================================= |
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286 | // Kernel Scheduling logic |
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287 | //============================================================================================= |
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288 | //Main of the processor contexts |
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289 | void main(processorCtx_t & runner) { |
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290 | // Because of a bug, we couldn't initialized the seed on construction |
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291 | // Do it here |
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292 | kernelTLS.rand_seed ^= rdtscl(); |
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293 | |
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294 | processor * this = runner.proc; |
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295 | verify(this); |
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296 | |
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297 | __cfadbg_print_safe(runtime_core, "Kernel : core %p starting\n", this); |
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298 | |
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299 | // register the processor unless it's the main thread which is handled in the boot sequence |
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300 | if(this != mainProcessor) { |
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301 | this->id = doregister2(this->cltr, this); |
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302 | ready_queue_grow( this->cltr ); |
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303 | } |
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304 | |
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305 | doregister(this->cltr, this); |
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306 | |
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307 | { |
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308 | // Setup preemption data |
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309 | preemption_scope scope = { this }; |
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310 | |
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311 | __cfadbg_print_safe(runtime_core, "Kernel : core %p started\n", this); |
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312 | |
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313 | $thread * readyThread = 0p; |
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314 | for( unsigned int spin_count = 0; ! __atomic_load_n(&this->do_terminate, __ATOMIC_SEQ_CST); spin_count++ ) { |
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315 | // Try to get the next thread |
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316 | readyThread = __next_thread( this->cltr ); |
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317 | |
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318 | // If no ready thread |
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319 | if( readyThread == 0p ) { |
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320 | // Block until a thread is ready |
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321 | readyThread = __halt(this); |
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322 | } |
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323 | |
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324 | // Check if we actually found a thread |
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325 | if( readyThread ) { |
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326 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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327 | /* paranoid */ verifyf( readyThread->state == Ready || readyThread->preempted != __NO_PREEMPTION, "state : %d, preempted %d\n", readyThread->state, readyThread->preempted); |
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328 | /* paranoid */ verifyf( readyThread->link.next == 0p, "Expected null got %p", readyThread->link.next ); |
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329 | |
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330 | // We found a thread run it |
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331 | __run_thread(this, readyThread); |
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332 | |
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333 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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334 | } |
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335 | } |
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336 | |
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337 | __cfadbg_print_safe(runtime_core, "Kernel : core %p stopping\n", this); |
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338 | } |
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339 | |
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340 | unregister(this->cltr, this); |
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341 | |
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342 | V( this->terminated ); |
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343 | |
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344 | // unregister the processor unless it's the main thread which is handled in the boot sequence |
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345 | if(this != mainProcessor) { |
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346 | ready_queue_shrink( this->cltr ); |
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347 | unregister2(this->cltr, this); |
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348 | } |
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349 | else { |
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350 | // HACK : the coroutine context switch expects this_thread to be set |
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351 | // and it make sense for it to be set in all other cases except here |
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352 | // fake it |
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353 | kernelTLS.this_thread = mainThread; |
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354 | } |
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355 | |
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356 | __cfadbg_print_safe(runtime_core, "Kernel : core %p terminated\n", this); |
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357 | |
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358 | stats_tls_tally(this->cltr); |
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359 | } |
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360 | |
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361 | static int * __volatile_errno() __attribute__((noinline)); |
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362 | static int * __volatile_errno() { asm(""); return &errno; } |
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363 | |
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364 | // KERNEL ONLY |
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365 | // runThread runs a thread by context switching |
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366 | // from the processor coroutine to the target thread |
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367 | static void __run_thread(processor * this, $thread * thrd_dst) { |
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368 | $coroutine * proc_cor = get_coroutine(this->runner); |
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369 | |
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370 | // Update global state |
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371 | kernelTLS.this_thread = thrd_dst; |
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372 | |
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373 | // set state of processor coroutine to inactive |
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374 | verify(proc_cor->state == Active); |
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375 | proc_cor->state = Blocked; |
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376 | |
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377 | // Actually run the thread |
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378 | RUNNING: while(true) { |
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379 | if(unlikely(thrd_dst->preempted)) { |
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380 | thrd_dst->preempted = __NO_PREEMPTION; |
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381 | verify(thrd_dst->state == Active || thrd_dst->state == Rerun); |
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382 | } else { |
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383 | verify(thrd_dst->state == Blocked || thrd_dst->state == Ready); // Ready means scheduled normally, blocked means rerun |
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384 | thrd_dst->state = Active; |
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385 | } |
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386 | |
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387 | __cfaabi_dbg_debug_do( |
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388 | thrd_dst->park_stale = true; |
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389 | thrd_dst->unpark_stale = true; |
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390 | ) |
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391 | |
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392 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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393 | /* paranoid */ verify( kernelTLS.this_thread == thrd_dst ); |
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394 | /* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) < ((uintptr_t)__get_stack(thrd_dst->curr_cor)->base ) || thrd_dst->curr_cor == proc_cor, "ERROR : Destination $thread %p has been corrupted.\n StackPointer too small.\n", thrd_dst ); // add escape condition if we are setting up the processor |
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395 | /* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) > ((uintptr_t)__get_stack(thrd_dst->curr_cor)->limit) || thrd_dst->curr_cor == proc_cor, "ERROR : Destination $thread %p has been corrupted.\n StackPointer too large.\n", thrd_dst ); // add escape condition if we are setting up the processor |
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396 | |
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397 | // set context switch to the thread that the processor is executing |
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398 | verify( thrd_dst->context.SP ); |
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399 | __cfactx_switch( &proc_cor->context, &thrd_dst->context ); |
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400 | // when __cfactx_switch returns we are back in the processor coroutine |
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401 | |
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402 | /* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) > ((uintptr_t)__get_stack(thrd_dst->curr_cor)->limit), "ERROR : Destination $thread %p has been corrupted.\n StackPointer too large.\n", thrd_dst ); |
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403 | /* paranoid */ verifyf( ((uintptr_t)thrd_dst->context.SP) < ((uintptr_t)__get_stack(thrd_dst->curr_cor)->base ), "ERROR : Destination $thread %p has been corrupted.\n StackPointer too small.\n", thrd_dst ); |
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404 | /* paranoid */ verify( kernelTLS.this_thread == thrd_dst ); |
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405 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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406 | |
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407 | |
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408 | // We just finished running a thread, there are a few things that could have happened. |
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409 | // 1 - Regular case : the thread has blocked and now one has scheduled it yet. |
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410 | // 2 - Racy case : the thread has blocked but someone has already tried to schedule it. |
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411 | // 4 - Preempted |
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412 | // In case 1, we may have won a race so we can't write to the state again. |
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413 | // In case 2, we lost the race so we now own the thread. |
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414 | |
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415 | if(unlikely(thrd_dst->preempted != __NO_PREEMPTION)) { |
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416 | // The thread was preempted, reschedule it and reset the flag |
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417 | __schedule_thread( thrd_dst ); |
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418 | break RUNNING; |
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419 | } |
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420 | |
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421 | // set state of processor coroutine to active and the thread to inactive |
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422 | static_assert(sizeof(thrd_dst->state) == sizeof(int)); |
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423 | enum coroutine_state old_state = __atomic_exchange_n(&thrd_dst->state, Blocked, __ATOMIC_SEQ_CST); |
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424 | __cfaabi_dbg_debug_do( thrd_dst->park_result = old_state; ) |
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425 | switch(old_state) { |
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426 | case Halted: |
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427 | // The thread has halted, it should never be scheduled/run again, leave it back to Halted and move on |
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428 | thrd_dst->state = Halted; |
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429 | |
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430 | // We may need to wake someone up here since |
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431 | unpark( this->destroyer __cfaabi_dbg_ctx2 ); |
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432 | this->destroyer = 0p; |
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433 | break RUNNING; |
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434 | case Active: |
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435 | // This is case 1, the regular case, nothing more is needed |
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436 | break RUNNING; |
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437 | case Rerun: |
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438 | // This is case 2, the racy case, someone tried to run this thread before it finished blocking |
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439 | // In this case, just run it again. |
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440 | continue RUNNING; |
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441 | default: |
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442 | // This makes no sense, something is wrong abort |
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443 | abort("Finished running a thread that was Blocked/Start/Primed %d\n", old_state); |
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444 | } |
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445 | } |
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446 | |
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447 | // Just before returning to the processor, set the processor coroutine to active |
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448 | proc_cor->state = Active; |
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449 | kernelTLS.this_thread = 0p; |
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450 | } |
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451 | |
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452 | // KERNEL_ONLY |
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453 | void returnToKernel() { |
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454 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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455 | $coroutine * proc_cor = get_coroutine(kernelTLS.this_processor->runner); |
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456 | $thread * thrd_src = kernelTLS.this_thread; |
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457 | |
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458 | // Run the thread on this processor |
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459 | { |
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460 | int local_errno = *__volatile_errno(); |
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461 | #if defined( __i386 ) || defined( __x86_64 ) |
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462 | __x87_store; |
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463 | #endif |
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464 | verify( proc_cor->context.SP ); |
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465 | __cfactx_switch( &thrd_src->context, &proc_cor->context ); |
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466 | #if defined( __i386 ) || defined( __x86_64 ) |
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467 | __x87_load; |
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468 | #endif |
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469 | *__volatile_errno() = local_errno; |
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470 | } |
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471 | |
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472 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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473 | /* paranoid */ verifyf( ((uintptr_t)thrd_src->context.SP) < ((uintptr_t)__get_stack(thrd_src->curr_cor)->base ), "ERROR : Returning $thread %p has been corrupted.\n StackPointer too small.\n", thrd_src ); |
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474 | /* paranoid */ verifyf( ((uintptr_t)thrd_src->context.SP) > ((uintptr_t)__get_stack(thrd_src->curr_cor)->limit), "ERROR : Returning $thread %p has been corrupted.\n StackPointer too large.\n", thrd_src ); |
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475 | } |
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476 | |
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477 | // KERNEL_ONLY |
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478 | // Context invoker for processors |
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479 | // This is the entry point for processors (kernel threads) |
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480 | // It effectively constructs a coroutine by stealing the pthread stack |
---|
481 | static void * __invoke_processor(void * arg) { |
---|
482 | processor * proc = (processor *) arg; |
---|
483 | kernelTLS.this_processor = proc; |
---|
484 | kernelTLS.this_thread = 0p; |
---|
485 | kernelTLS.preemption_state.[enabled, disable_count] = [false, 1]; |
---|
486 | // SKULLDUGGERY: We want to create a context for the processor coroutine |
---|
487 | // which is needed for the 2-step context switch. However, there is no reason |
---|
488 | // to waste the perfectly valid stack create by pthread. |
---|
489 | current_stack_info_t info; |
---|
490 | __stack_t ctx; |
---|
491 | info.storage = &ctx; |
---|
492 | (proc->runner){ proc, &info }; |
---|
493 | |
---|
494 | __cfaabi_dbg_print_safe("Coroutine : created stack %p\n", get_coroutine(proc->runner)->stack.storage); |
---|
495 | |
---|
496 | //Set global state |
---|
497 | kernelTLS.this_thread = 0p; |
---|
498 | |
---|
499 | //We now have a proper context from which to schedule threads |
---|
500 | __cfadbg_print_safe(runtime_core, "Kernel : core %p created (%p, %p)\n", proc, &proc->runner, &ctx); |
---|
501 | |
---|
502 | // SKULLDUGGERY: Since the coroutine doesn't have its own stack, we can't |
---|
503 | // resume it to start it like it normally would, it will just context switch |
---|
504 | // back to here. Instead directly call the main since we already are on the |
---|
505 | // appropriate stack. |
---|
506 | get_coroutine(proc->runner)->state = Active; |
---|
507 | main( proc->runner ); |
---|
508 | get_coroutine(proc->runner)->state = Halted; |
---|
509 | |
---|
510 | // Main routine of the core returned, the core is now fully terminated |
---|
511 | __cfadbg_print_safe(runtime_core, "Kernel : core %p main ended (%p)\n", proc, &proc->runner); |
---|
512 | |
---|
513 | return 0p; |
---|
514 | } |
---|
515 | |
---|
516 | static void Abort( int ret, const char func[] ) { |
---|
517 | if ( ret ) { // pthread routines return errno values |
---|
518 | abort( "%s : internal error, error(%d) %s.", func, ret, strerror( ret ) ); |
---|
519 | } // if |
---|
520 | } // Abort |
---|
521 | |
---|
522 | void * __create_pthread( pthread_t * pthread, void * (*start)(void *), void * arg ) { |
---|
523 | pthread_attr_t attr; |
---|
524 | |
---|
525 | Abort( pthread_attr_init( &attr ), "pthread_attr_init" ); // initialize attribute |
---|
526 | |
---|
527 | size_t stacksize; |
---|
528 | // default stack size, normally defined by shell limit |
---|
529 | Abort( pthread_attr_getstacksize( &attr, &stacksize ), "pthread_attr_getstacksize" ); |
---|
530 | assert( stacksize >= PTHREAD_STACK_MIN ); |
---|
531 | |
---|
532 | void * stack; |
---|
533 | __cfaabi_dbg_debug_do( |
---|
534 | stack = memalign( __page_size, stacksize + __page_size ); |
---|
535 | // pthread has no mechanism to create the guard page in user supplied stack. |
---|
536 | if ( mprotect( stack, __page_size, PROT_NONE ) == -1 ) { |
---|
537 | abort( "mprotect : internal error, mprotect failure, error(%d) %s.", errno, strerror( errno ) ); |
---|
538 | } // if |
---|
539 | ); |
---|
540 | __cfaabi_dbg_no_debug_do( |
---|
541 | stack = malloc( stacksize ); |
---|
542 | ); |
---|
543 | |
---|
544 | Abort( pthread_attr_setstack( &attr, stack, stacksize ), "pthread_attr_setstack" ); |
---|
545 | |
---|
546 | Abort( pthread_create( pthread, &attr, start, arg ), "pthread_create" ); |
---|
547 | return stack; |
---|
548 | } |
---|
549 | |
---|
550 | // KERNEL_ONLY |
---|
551 | static void __kernel_first_resume( processor * this ) { |
---|
552 | $thread * src = mainThread; |
---|
553 | $coroutine * dst = get_coroutine(this->runner); |
---|
554 | |
---|
555 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
556 | |
---|
557 | kernelTLS.this_thread->curr_cor = dst; |
---|
558 | __stack_prepare( &dst->stack, 65000 ); |
---|
559 | __cfactx_start(main, dst, this->runner, __cfactx_invoke_coroutine); |
---|
560 | |
---|
561 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
562 | |
---|
563 | dst->last = &src->self_cor; |
---|
564 | dst->starter = dst->starter ? dst->starter : &src->self_cor; |
---|
565 | |
---|
566 | // make sure the current state is still correct |
---|
567 | /* paranoid */ verify(src->state == Ready); |
---|
568 | |
---|
569 | // context switch to specified coroutine |
---|
570 | verify( dst->context.SP ); |
---|
571 | __cfactx_switch( &src->context, &dst->context ); |
---|
572 | // when __cfactx_switch returns we are back in the src coroutine |
---|
573 | |
---|
574 | mainThread->curr_cor = &mainThread->self_cor; |
---|
575 | |
---|
576 | // make sure the current state has been update |
---|
577 | /* paranoid */ verify(src->state == Active); |
---|
578 | |
---|
579 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
580 | } |
---|
581 | |
---|
582 | // KERNEL_ONLY |
---|
583 | static void __kernel_last_resume( processor * this ) { |
---|
584 | $coroutine * src = &mainThread->self_cor; |
---|
585 | $coroutine * dst = get_coroutine(this->runner); |
---|
586 | |
---|
587 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
588 | verify( dst->starter == src ); |
---|
589 | verify( dst->context.SP ); |
---|
590 | |
---|
591 | // SKULLDUGGERY in debug the processors check that the |
---|
592 | // stack is still within the limit of the stack limits after running a thread. |
---|
593 | // that check doesn't make sense if we context switch to the processor using the |
---|
594 | // coroutine semantics. Since this is a special case, use the current context |
---|
595 | // info to populate these fields. |
---|
596 | __cfaabi_dbg_debug_do( |
---|
597 | __stack_context_t ctx; |
---|
598 | CtxGet( ctx ); |
---|
599 | mainThread->context.SP = ctx.SP; |
---|
600 | mainThread->context.FP = ctx.FP; |
---|
601 | ) |
---|
602 | |
---|
603 | // context switch to the processor |
---|
604 | __cfactx_switch( &src->context, &dst->context ); |
---|
605 | } |
---|
606 | |
---|
607 | //----------------------------------------------------------------------------- |
---|
608 | // Scheduler routines |
---|
609 | // KERNEL ONLY |
---|
610 | void __schedule_thread( $thread * thrd ) { |
---|
611 | /* paranoid */ verify( thrd ); |
---|
612 | /* paranoid */ verify( thrd->state != Halted ); |
---|
613 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
614 | /* paranoid */ #if defined( __CFA_WITH_VERIFY__ ) |
---|
615 | /* paranoid */ if( thrd->state == Blocked || thrd->state == Start ) assertf( thrd->preempted == __NO_PREEMPTION, |
---|
616 | "Error inactive thread marked as preempted, state %d, preemption %d\n", thrd->state, thrd->preempted ); |
---|
617 | /* paranoid */ if( thrd->preempted != __NO_PREEMPTION ) assertf(thrd->state == Active || thrd->state == Rerun, |
---|
618 | "Error preempted thread marked as not currently running, state %d, preemption %d\n", thrd->state, thrd->preempted ); |
---|
619 | /* paranoid */ #endif |
---|
620 | /* paranoid */ verifyf( thrd->link.next == 0p, "Expected null got %p", thrd->link.next ); |
---|
621 | |
---|
622 | if (thrd->preempted == __NO_PREEMPTION) thrd->state = Ready; |
---|
623 | |
---|
624 | ready_schedule_lock(thrd->curr_cluster, kernelTLS.this_processor); |
---|
625 | push( thrd->curr_cluster, thrd ); |
---|
626 | |
---|
627 | __wake_one(thrd->curr_cluster); |
---|
628 | ready_schedule_unlock(thrd->curr_cluster, kernelTLS.this_processor); |
---|
629 | |
---|
630 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
631 | } |
---|
632 | |
---|
633 | // KERNEL ONLY |
---|
634 | static $thread * __next_thread(cluster * this) with( *this ) { |
---|
635 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
636 | |
---|
637 | ready_schedule_lock(this, kernelTLS.this_processor); |
---|
638 | $thread * head = pop( this ); |
---|
639 | ready_schedule_unlock(this, kernelTLS.this_processor); |
---|
640 | |
---|
641 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
642 | return head; |
---|
643 | } |
---|
644 | |
---|
645 | // KERNEL ONLY unpark with out disabling interrupts |
---|
646 | void __unpark( $thread * thrd __cfaabi_dbg_ctx_param2 ) { |
---|
647 | static_assert(sizeof(thrd->state) == sizeof(int)); |
---|
648 | |
---|
649 | // record activity |
---|
650 | __cfaabi_dbg_debug_do( char * old_caller = thrd->unpark_caller; ) |
---|
651 | __cfaabi_dbg_record_thrd( *thrd, false, caller ); |
---|
652 | |
---|
653 | enum coroutine_state old_state = __atomic_exchange_n(&thrd->state, Rerun, __ATOMIC_SEQ_CST); |
---|
654 | __cfaabi_dbg_debug_do( thrd->unpark_result = old_state; ) |
---|
655 | switch(old_state) { |
---|
656 | case Active: |
---|
657 | // Wake won the race, the thread will reschedule/rerun itself |
---|
658 | break; |
---|
659 | case Blocked: |
---|
660 | /* paranoid */ verify( ! thrd->preempted != __NO_PREEMPTION ); |
---|
661 | |
---|
662 | // Wake lost the race, |
---|
663 | thrd->state = Blocked; |
---|
664 | __schedule_thread( thrd ); |
---|
665 | break; |
---|
666 | case Rerun: |
---|
667 | abort("More than one thread attempted to schedule thread %p\n", thrd); |
---|
668 | break; |
---|
669 | case Halted: |
---|
670 | case Start: |
---|
671 | case Primed: |
---|
672 | default: |
---|
673 | // This makes no sense, something is wrong abort |
---|
674 | abort(); |
---|
675 | } |
---|
676 | } |
---|
677 | |
---|
678 | void unpark( $thread * thrd __cfaabi_dbg_ctx_param2 ) { |
---|
679 | if( !thrd ) return; |
---|
680 | |
---|
681 | disable_interrupts(); |
---|
682 | __unpark( thrd __cfaabi_dbg_ctx_fwd2 ); |
---|
683 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
684 | } |
---|
685 | |
---|
686 | void park( __cfaabi_dbg_ctx_param ) { |
---|
687 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
688 | disable_interrupts(); |
---|
689 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
690 | /* paranoid */ verify( kernelTLS.this_thread->preempted == __NO_PREEMPTION ); |
---|
691 | |
---|
692 | // record activity |
---|
693 | __cfaabi_dbg_record_thrd( *kernelTLS.this_thread, true, caller ); |
---|
694 | |
---|
695 | returnToKernel(); |
---|
696 | |
---|
697 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
698 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
699 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
700 | |
---|
701 | } |
---|
702 | |
---|
703 | // KERNEL ONLY |
---|
704 | void __leave_thread() { |
---|
705 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
706 | returnToKernel(); |
---|
707 | abort(); |
---|
708 | } |
---|
709 | |
---|
710 | // KERNEL ONLY |
---|
711 | bool force_yield( __Preemption_Reason reason ) { |
---|
712 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
713 | disable_interrupts(); |
---|
714 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
715 | |
---|
716 | $thread * thrd = kernelTLS.this_thread; |
---|
717 | /* paranoid */ verify(thrd->state == Active || thrd->state == Rerun); |
---|
718 | |
---|
719 | // SKULLDUGGERY: It is possible that we are preempting this thread just before |
---|
720 | // it was going to park itself. If that is the case and it is already using the |
---|
721 | // intrusive fields then we can't use them to preempt the thread |
---|
722 | // If that is the case, abandon the preemption. |
---|
723 | bool preempted = false; |
---|
724 | if(thrd->link.next == 0p) { |
---|
725 | preempted = true; |
---|
726 | thrd->preempted = reason; |
---|
727 | returnToKernel(); |
---|
728 | } |
---|
729 | |
---|
730 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
731 | enable_interrupts_noPoll(); |
---|
732 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
733 | |
---|
734 | return preempted; |
---|
735 | } |
---|
736 | |
---|
737 | //============================================================================================= |
---|
738 | // Kernel Setup logic |
---|
739 | //============================================================================================= |
---|
740 | //----------------------------------------------------------------------------- |
---|
741 | // Kernel boot procedures |
---|
742 | static void __kernel_startup(void) { |
---|
743 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
744 | __cfadbg_print_safe(runtime_core, "Kernel : Starting\n"); |
---|
745 | |
---|
746 | __page_size = sysconf( _SC_PAGESIZE ); |
---|
747 | |
---|
748 | __cfa_dbg_global_clusters.list{ __get }; |
---|
749 | __cfa_dbg_global_clusters.lock{}; |
---|
750 | |
---|
751 | // Initialize the main cluster |
---|
752 | mainCluster = (cluster *)&storage_mainCluster; |
---|
753 | (*mainCluster){"Main Cluster"}; |
---|
754 | |
---|
755 | __cfadbg_print_safe(runtime_core, "Kernel : Main cluster ready\n"); |
---|
756 | |
---|
757 | // Start by initializing the main thread |
---|
758 | // SKULLDUGGERY: the mainThread steals the process main thread |
---|
759 | // which will then be scheduled by the mainProcessor normally |
---|
760 | mainThread = ($thread *)&storage_mainThread; |
---|
761 | current_stack_info_t info; |
---|
762 | info.storage = (__stack_t*)&storage_mainThreadCtx; |
---|
763 | (*mainThread){ &info }; |
---|
764 | |
---|
765 | __cfadbg_print_safe(runtime_core, "Kernel : Main thread ready\n"); |
---|
766 | |
---|
767 | |
---|
768 | |
---|
769 | // Construct the processor context of the main processor |
---|
770 | void ?{}(processorCtx_t & this, processor * proc) { |
---|
771 | (this.__cor){ "Processor" }; |
---|
772 | this.__cor.starter = 0p; |
---|
773 | this.proc = proc; |
---|
774 | } |
---|
775 | |
---|
776 | void ?{}(processor & this) with( this ) { |
---|
777 | name = "Main Processor"; |
---|
778 | cltr = mainCluster; |
---|
779 | terminated{ 0 }; |
---|
780 | do_terminate = false; |
---|
781 | preemption_alarm = 0p; |
---|
782 | pending_preemption = false; |
---|
783 | kernel_thread = pthread_self(); |
---|
784 | id = -1u; |
---|
785 | |
---|
786 | runner{ &this }; |
---|
787 | __cfadbg_print_safe(runtime_core, "Kernel : constructed main processor context %p\n", &runner); |
---|
788 | } |
---|
789 | |
---|
790 | // Initialize the main processor and the main processor ctx |
---|
791 | // (the coroutine that contains the processing control flow) |
---|
792 | mainProcessor = (processor *)&storage_mainProcessor; |
---|
793 | (*mainProcessor){}; |
---|
794 | |
---|
795 | mainProcessor->id = doregister2(mainCluster, mainProcessor); |
---|
796 | |
---|
797 | //initialize the global state variables |
---|
798 | kernelTLS.this_processor = mainProcessor; |
---|
799 | kernelTLS.this_thread = mainThread; |
---|
800 | |
---|
801 | // Enable preemption |
---|
802 | kernel_start_preemption(); |
---|
803 | |
---|
804 | // Add the main thread to the ready queue |
---|
805 | // once resume is called on mainProcessor->runner the mainThread needs to be scheduled like any normal thread |
---|
806 | __schedule_thread(mainThread); |
---|
807 | |
---|
808 | // SKULLDUGGERY: Force a context switch to the main processor to set the main thread's context to the current UNIX |
---|
809 | // context. Hence, the main thread does not begin through __cfactx_invoke_thread, like all other threads. The trick here is that |
---|
810 | // mainThread is on the ready queue when this call is made. |
---|
811 | __kernel_first_resume( kernelTLS.this_processor ); |
---|
812 | |
---|
813 | |
---|
814 | // THE SYSTEM IS NOW COMPLETELY RUNNING |
---|
815 | |
---|
816 | |
---|
817 | // Now that the system is up, finish creating systems that need threading |
---|
818 | __kernel_io_finish_start( *mainCluster ); |
---|
819 | |
---|
820 | |
---|
821 | __cfadbg_print_safe(runtime_core, "Kernel : Started\n--------------------------------------------------\n\n"); |
---|
822 | |
---|
823 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
824 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
825 | verify( TL_GET( preemption_state.enabled ) ); |
---|
826 | } |
---|
827 | |
---|
828 | static void __kernel_shutdown(void) { |
---|
829 | //Before we start shutting things down, wait for systems that need threading to shutdown |
---|
830 | __kernel_io_prepare_stop( *mainCluster ); |
---|
831 | |
---|
832 | /* paranoid */ verify( TL_GET( preemption_state.enabled ) ); |
---|
833 | disable_interrupts(); |
---|
834 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
835 | |
---|
836 | __cfadbg_print_safe(runtime_core, "\n--------------------------------------------------\nKernel : Shutting down\n"); |
---|
837 | |
---|
838 | // SKULLDUGGERY: Notify the mainProcessor it needs to terminates. |
---|
839 | // When its coroutine terminates, it return control to the mainThread |
---|
840 | // which is currently here |
---|
841 | __atomic_store_n(&mainProcessor->do_terminate, true, __ATOMIC_RELEASE); |
---|
842 | __kernel_last_resume( kernelTLS.this_processor ); |
---|
843 | mainThread->self_cor.state = Halted; |
---|
844 | |
---|
845 | // THE SYSTEM IS NOW COMPLETELY STOPPED |
---|
846 | |
---|
847 | // Disable preemption |
---|
848 | kernel_stop_preemption(); |
---|
849 | |
---|
850 | unregister2(mainCluster, mainProcessor); |
---|
851 | |
---|
852 | // Destroy the main processor and its context in reverse order of construction |
---|
853 | // These were manually constructed so we need manually destroy them |
---|
854 | void ^?{}(processor & this) with( this ){ |
---|
855 | /* paranoid */ verify( this.do_terminate == true ); |
---|
856 | __cfaabi_dbg_print_safe("Kernel : destroyed main processor context %p\n", &runner); |
---|
857 | } |
---|
858 | |
---|
859 | ^(*mainProcessor){}; |
---|
860 | |
---|
861 | // Final step, destroy the main thread since it is no longer needed |
---|
862 | |
---|
863 | // Since we provided a stack to this taxk it will not destroy anything |
---|
864 | /* paranoid */ verify(mainThread->self_cor.stack.storage == (__stack_t*)(((uintptr_t)&storage_mainThreadCtx)| 0x1)); |
---|
865 | ^(*mainThread){}; |
---|
866 | |
---|
867 | ^(*mainCluster){}; |
---|
868 | |
---|
869 | ^(__cfa_dbg_global_clusters.list){}; |
---|
870 | ^(__cfa_dbg_global_clusters.lock){}; |
---|
871 | |
---|
872 | __cfadbg_print_safe(runtime_core, "Kernel : Shutdown complete\n"); |
---|
873 | } |
---|
874 | |
---|
875 | //============================================================================================= |
---|
876 | // Kernel Idle Sleep |
---|
877 | //============================================================================================= |
---|
878 | static $thread * __halt(processor * this) with( *this ) { |
---|
879 | if( do_terminate ) return 0p; |
---|
880 | |
---|
881 | // First, lock the cluster idle |
---|
882 | lock( cltr->idle_lock __cfaabi_dbg_ctx2 ); |
---|
883 | |
---|
884 | // Check if we can find a thread |
---|
885 | if( $thread * found = __next_thread( cltr ) ) { |
---|
886 | unlock( cltr->idle_lock ); |
---|
887 | return found; |
---|
888 | } |
---|
889 | |
---|
890 | // Move this processor from the active list to the idle list |
---|
891 | move_to_front(cltr->procs, cltr->idles, *this); |
---|
892 | |
---|
893 | // Unlock the idle lock so we don't go to sleep with a lock |
---|
894 | unlock (cltr->idle_lock); |
---|
895 | |
---|
896 | // We are ready to sleep |
---|
897 | __cfadbg_print_safe(runtime_core, "Kernel : Processor %p ready to sleep\n", this); |
---|
898 | wait( idle ); |
---|
899 | |
---|
900 | // We have woken up |
---|
901 | __cfadbg_print_safe(runtime_core, "Kernel : Processor %p woke up and ready to run\n", this); |
---|
902 | |
---|
903 | // Get ourself off the idle list |
---|
904 | with( *cltr ) { |
---|
905 | lock (idle_lock __cfaabi_dbg_ctx2); |
---|
906 | move_to_front(idles, procs, *this); |
---|
907 | unlock(idle_lock); |
---|
908 | } |
---|
909 | |
---|
910 | // Don't check the ready queue again, we may not be in a position to run a thread |
---|
911 | return 0p; |
---|
912 | } |
---|
913 | |
---|
914 | // Wake a thread from the front if there are any |
---|
915 | static bool __wake_one(cluster * this) { |
---|
916 | // First, lock the cluster idle |
---|
917 | lock( this->idle_lock __cfaabi_dbg_ctx2 ); |
---|
918 | |
---|
919 | // Check if there is someone to wake up |
---|
920 | if( !this->idles.head ) { |
---|
921 | // Nope unlock and return false |
---|
922 | unlock( this->idle_lock ); |
---|
923 | return false; |
---|
924 | } |
---|
925 | |
---|
926 | // Wake them up |
---|
927 | __cfadbg_print_safe(runtime_core, "Kernel : waking Processor %p\n", this->idles.head); |
---|
928 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
929 | post( this->idles.head->idle ); |
---|
930 | |
---|
931 | // Unlock and return true |
---|
932 | unlock( this->idle_lock ); |
---|
933 | return true; |
---|
934 | } |
---|
935 | |
---|
936 | // Unconditionnaly wake a thread |
---|
937 | static bool __wake_proc(processor * this) { |
---|
938 | __cfadbg_print_safe(runtime_core, "Kernel : waking Processor %p\n", this); |
---|
939 | |
---|
940 | disable_interrupts(); |
---|
941 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
942 | bool ret = post( this->idle ); |
---|
943 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
944 | |
---|
945 | return ret; |
---|
946 | } |
---|
947 | |
---|
948 | //============================================================================================= |
---|
949 | // Unexpected Terminating logic |
---|
950 | //============================================================================================= |
---|
951 | static __spinlock_t kernel_abort_lock; |
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952 | static bool kernel_abort_called = false; |
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953 | |
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954 | void * kernel_abort(void) __attribute__ ((__nothrow__)) { |
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955 | // abort cannot be recursively entered by the same or different processors because all signal handlers return when |
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956 | // the globalAbort flag is true. |
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957 | lock( kernel_abort_lock __cfaabi_dbg_ctx2 ); |
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958 | |
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959 | // first task to abort ? |
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960 | if ( kernel_abort_called ) { // not first task to abort ? |
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961 | unlock( kernel_abort_lock ); |
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962 | |
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963 | sigset_t mask; |
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964 | sigemptyset( &mask ); |
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965 | sigaddset( &mask, SIGALRM ); // block SIGALRM signals |
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966 | sigaddset( &mask, SIGUSR1 ); // block SIGALRM signals |
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967 | sigsuspend( &mask ); // block the processor to prevent further damage during abort |
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968 | _exit( EXIT_FAILURE ); // if processor unblocks before it is killed, terminate it |
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969 | } |
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970 | else { |
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971 | kernel_abort_called = true; |
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972 | unlock( kernel_abort_lock ); |
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973 | } |
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974 | |
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975 | return kernelTLS.this_thread; |
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976 | } |
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977 | |
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978 | void kernel_abort_msg( void * kernel_data, char * abort_text, int abort_text_size ) { |
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979 | $thread * thrd = kernel_data; |
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980 | |
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981 | if(thrd) { |
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982 | int len = snprintf( abort_text, abort_text_size, "Error occurred while executing thread %.256s (%p)", thrd->self_cor.name, thrd ); |
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983 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
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984 | |
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985 | if ( &thrd->self_cor != thrd->curr_cor ) { |
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986 | len = snprintf( abort_text, abort_text_size, " in coroutine %.256s (%p).\n", thrd->curr_cor->name, thrd->curr_cor ); |
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987 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
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988 | } |
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989 | else { |
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990 | __cfaabi_bits_write( STDERR_FILENO, ".\n", 2 ); |
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991 | } |
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992 | } |
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993 | else { |
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994 | int len = snprintf( abort_text, abort_text_size, "Error occurred outside of any thread.\n" ); |
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995 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
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996 | } |
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997 | } |
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998 | |
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999 | int kernel_abort_lastframe( void ) __attribute__ ((__nothrow__)) { |
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1000 | return get_coroutine(kernelTLS.this_thread) == get_coroutine(mainThread) ? 4 : 2; |
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1001 | } |
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1002 | |
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1003 | static __spinlock_t kernel_debug_lock; |
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1004 | |
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1005 | extern "C" { |
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1006 | void __cfaabi_bits_acquire() { |
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1007 | lock( kernel_debug_lock __cfaabi_dbg_ctx2 ); |
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1008 | } |
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1009 | |
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1010 | void __cfaabi_bits_release() { |
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1011 | unlock( kernel_debug_lock ); |
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1012 | } |
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1013 | } |
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1014 | |
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1015 | //============================================================================================= |
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1016 | // Kernel Utilities |
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1017 | //============================================================================================= |
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1018 | //----------------------------------------------------------------------------- |
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1019 | // Locks |
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1020 | void ?{}( semaphore & this, int count = 1 ) { |
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1021 | (this.lock){}; |
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1022 | this.count = count; |
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1023 | (this.waiting){}; |
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1024 | } |
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1025 | void ^?{}(semaphore & this) {} |
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1026 | |
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1027 | bool P(semaphore & this) with( this ){ |
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1028 | lock( lock __cfaabi_dbg_ctx2 ); |
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1029 | count -= 1; |
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1030 | if ( count < 0 ) { |
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1031 | // queue current task |
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1032 | append( waiting, kernelTLS.this_thread ); |
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1033 | |
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1034 | // atomically release spin lock and block |
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1035 | unlock( lock ); |
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1036 | park( __cfaabi_dbg_ctx ); |
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1037 | return true; |
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1038 | } |
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1039 | else { |
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1040 | unlock( lock ); |
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1041 | return false; |
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1042 | } |
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1043 | } |
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1044 | |
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1045 | bool V(semaphore & this) with( this ) { |
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1046 | $thread * thrd = 0p; |
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1047 | lock( lock __cfaabi_dbg_ctx2 ); |
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1048 | count += 1; |
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1049 | if ( count <= 0 ) { |
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1050 | // remove task at head of waiting list |
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1051 | thrd = pop_head( waiting ); |
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1052 | } |
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1053 | |
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1054 | unlock( lock ); |
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1055 | |
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1056 | // make new owner |
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1057 | unpark( thrd __cfaabi_dbg_ctx2 ); |
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1058 | |
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1059 | return thrd != 0p; |
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1060 | } |
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1061 | |
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1062 | bool V(semaphore & this, unsigned diff) with( this ) { |
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1063 | $thread * thrd = 0p; |
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1064 | lock( lock __cfaabi_dbg_ctx2 ); |
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1065 | int release = max(-count, (int)diff); |
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1066 | count += diff; |
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1067 | for(release) { |
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1068 | unpark( pop_head( waiting ) __cfaabi_dbg_ctx2 ); |
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1069 | } |
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1070 | |
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1071 | unlock( lock ); |
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1072 | |
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1073 | return thrd != 0p; |
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1074 | } |
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1075 | |
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1076 | //----------------------------------------------------------------------------- |
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1077 | // Global Queues |
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1078 | void doregister( cluster & cltr ) { |
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1079 | lock ( __cfa_dbg_global_clusters.lock __cfaabi_dbg_ctx2); |
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1080 | push_front( __cfa_dbg_global_clusters.list, cltr ); |
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1081 | unlock ( __cfa_dbg_global_clusters.lock ); |
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1082 | } |
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1083 | |
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1084 | void unregister( cluster & cltr ) { |
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1085 | lock ( __cfa_dbg_global_clusters.lock __cfaabi_dbg_ctx2); |
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1086 | remove( __cfa_dbg_global_clusters.list, cltr ); |
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1087 | unlock( __cfa_dbg_global_clusters.lock ); |
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1088 | } |
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1089 | |
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1090 | void doregister( cluster * cltr, $thread & thrd ) { |
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1091 | lock (cltr->thread_list_lock __cfaabi_dbg_ctx2); |
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1092 | cltr->nthreads += 1; |
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1093 | push_front(cltr->threads, thrd); |
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1094 | unlock (cltr->thread_list_lock); |
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1095 | } |
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1096 | |
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1097 | void unregister( cluster * cltr, $thread & thrd ) { |
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1098 | lock (cltr->thread_list_lock __cfaabi_dbg_ctx2); |
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1099 | remove(cltr->threads, thrd ); |
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1100 | cltr->nthreads -= 1; |
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1101 | unlock(cltr->thread_list_lock); |
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1102 | } |
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1103 | |
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1104 | void doregister( cluster * cltr, processor * proc ) { |
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1105 | lock (cltr->idle_lock __cfaabi_dbg_ctx2); |
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1106 | cltr->nprocessors += 1; |
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1107 | push_front(cltr->procs, *proc); |
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1108 | unlock (cltr->idle_lock); |
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1109 | } |
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1110 | |
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1111 | void unregister( cluster * cltr, processor * proc ) { |
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1112 | lock (cltr->idle_lock __cfaabi_dbg_ctx2); |
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1113 | remove(cltr->procs, *proc ); |
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1114 | cltr->nprocessors -= 1; |
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1115 | unlock(cltr->idle_lock); |
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1116 | } |
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1117 | |
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1118 | //----------------------------------------------------------------------------- |
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1119 | // Debug |
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1120 | __cfaabi_dbg_debug_do( |
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1121 | extern "C" { |
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1122 | void __cfaabi_dbg_record_lock(__spinlock_t & this, const char prev_name[]) { |
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1123 | this.prev_name = prev_name; |
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1124 | this.prev_thrd = kernelTLS.this_thread; |
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1125 | } |
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1126 | |
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1127 | void __cfaabi_dbg_record_thrd($thread & this, bool park, const char prev_name[]) { |
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1128 | if(park) { |
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1129 | this.park_caller = prev_name; |
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1130 | this.park_stale = false; |
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1131 | } |
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1132 | else { |
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1133 | this.unpark_caller = prev_name; |
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1134 | this.unpark_stale = false; |
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1135 | } |
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1136 | } |
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1137 | } |
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1138 | ) |
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1139 | |
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1140 | //----------------------------------------------------------------------------- |
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1141 | // Debug |
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1142 | bool threading_enabled(void) __attribute__((const)) { |
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1143 | return true; |
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1144 | } |
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1145 | // Local Variables: // |
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1146 | // mode: c // |
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1147 | // tab-width: 4 // |
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1148 | // End: // |
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