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 : Thu Jul 9 06:22:54 2020 |
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13 | // Update Count : 66 |
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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 | #include <stdio.h> |
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24 | #include <fenv.h> |
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25 | #include <signal.h> |
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26 | #include <unistd.h> |
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27 | #include <limits.h> // PTHREAD_STACK_MIN |
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28 | #include <sys/mman.h> // mprotect |
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29 | extern "C" { |
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30 | #include <sys/resource.h> |
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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 bool __has_next_thread(cluster * this); |
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121 | static void __run_thread(processor * this, $thread * dst); |
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122 | static bool __wake_proc(processor *); |
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123 | static bool __wake_one(struct __processor_id_t * id, cluster * cltr); |
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124 | static void __halt(processor * this); |
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125 | |
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126 | //----------------------------------------------------------------------------- |
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127 | // Kernel storage |
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128 | KERNEL_STORAGE(cluster, mainCluster); |
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129 | KERNEL_STORAGE(processor, mainProcessor); |
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130 | KERNEL_STORAGE($thread, mainThread); |
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131 | KERNEL_STORAGE(__stack_t, mainThreadCtx); |
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132 | KERNEL_STORAGE(__scheduler_RWLock_t, __scheduler_lock); |
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133 | #if !defined(__CFA_NO_STATISTICS__) |
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134 | KERNEL_STORAGE(__stats_t, mainProcStats); |
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135 | #endif |
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136 | |
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137 | cluster * mainCluster; |
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138 | processor * mainProcessor; |
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139 | $thread * mainThread; |
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140 | __scheduler_RWLock_t * __scheduler_lock; |
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141 | |
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142 | extern "C" { |
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143 | struct { __dllist_t(cluster) list; __spinlock_t lock; } __cfa_dbg_global_clusters; |
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144 | } |
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145 | |
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146 | size_t __page_size = 0; |
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147 | |
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148 | //----------------------------------------------------------------------------- |
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149 | // Global state |
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150 | thread_local struct KernelThreadData kernelTLS __attribute__ ((tls_model ( "initial-exec" ))) @= { |
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151 | NULL, // cannot use 0p |
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152 | NULL, |
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153 | NULL, |
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154 | { 1, false, false }, |
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155 | }; |
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156 | |
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157 | //----------------------------------------------------------------------------- |
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158 | // Struct to steal stack |
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159 | struct current_stack_info_t { |
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160 | __stack_t * storage; // pointer to stack object |
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161 | void * base; // base of stack |
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162 | void * limit; // stack grows towards stack limit |
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163 | void * context; // address of cfa_context_t |
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164 | }; |
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165 | |
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166 | void ?{}( current_stack_info_t & this ) { |
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167 | __stack_context_t ctx; |
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168 | CtxGet( ctx ); |
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169 | this.base = ctx.FP; |
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170 | |
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171 | rlimit r; |
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172 | getrlimit( RLIMIT_STACK, &r); |
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173 | size_t size = r.rlim_cur; |
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174 | |
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175 | this.limit = (void *)(((intptr_t)this.base) - size); |
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176 | this.context = &storage_mainThreadCtx; |
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177 | } |
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178 | |
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179 | //----------------------------------------------------------------------------- |
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180 | // Main thread construction |
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181 | |
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182 | void ?{}( $coroutine & this, current_stack_info_t * info) with( this ) { |
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183 | stack.storage = info->storage; |
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184 | with(*stack.storage) { |
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185 | limit = info->limit; |
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186 | base = info->base; |
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187 | } |
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188 | __attribute__((may_alias)) intptr_t * istorage = (intptr_t*) &stack.storage; |
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189 | *istorage |= 0x1; |
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190 | name = "Main Thread"; |
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191 | state = Start; |
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192 | starter = 0p; |
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193 | last = 0p; |
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194 | cancellation = 0p; |
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195 | } |
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196 | |
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197 | void ?{}( $thread & this, current_stack_info_t * info) with( this ) { |
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198 | ticket = 1; |
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199 | state = Start; |
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200 | self_cor{ info }; |
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201 | curr_cor = &self_cor; |
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202 | curr_cluster = mainCluster; |
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203 | self_mon.owner = &this; |
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204 | self_mon.recursion = 1; |
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205 | self_mon_p = &self_mon; |
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206 | link.next = 0p; |
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207 | link.prev = 0p; |
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208 | |
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209 | node.next = 0p; |
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210 | node.prev = 0p; |
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211 | doregister(curr_cluster, this); |
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212 | |
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213 | monitors{ &self_mon_p, 1, (fptr_t)0 }; |
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214 | } |
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215 | |
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216 | //----------------------------------------------------------------------------- |
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217 | // Processor coroutine |
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218 | void ?{}(processorCtx_t & this) { |
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219 | |
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220 | } |
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221 | |
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222 | // Construct the processor context of non-main processors |
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223 | static void ?{}(processorCtx_t & this, processor * proc, current_stack_info_t * info) { |
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224 | (this.__cor){ info }; |
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225 | this.proc = proc; |
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226 | } |
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227 | |
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228 | static void * __invoke_processor(void * arg); |
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229 | |
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230 | void ?{}(processor & this, const char name[], cluster & _cltr) with( this ) { |
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231 | this.name = name; |
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232 | this.cltr = &_cltr; |
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233 | id = -1u; |
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234 | terminated{ 0 }; |
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235 | destroyer = 0p; |
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236 | do_terminate = false; |
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237 | preemption_alarm = 0p; |
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238 | pending_preemption = false; |
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239 | runner.proc = &this; |
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240 | |
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241 | #if !defined(__CFA_NO_STATISTICS__) |
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242 | print_stats = 0; |
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243 | print_halts = false; |
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244 | #endif |
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245 | |
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246 | idle{}; |
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247 | |
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248 | __cfadbg_print_safe(runtime_core, "Kernel : Starting core %p\n", &this); |
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249 | |
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250 | this.stack = __create_pthread( &this.kernel_thread, __invoke_processor, (void *)&this ); |
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251 | __atomic_fetch_add( &cltr->nprocessors, 1u, __ATOMIC_SEQ_CST ); |
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252 | |
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253 | __cfadbg_print_safe(runtime_core, "Kernel : core %p created\n", &this); |
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254 | } |
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255 | |
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256 | void ^?{}(processor & this) with( this ){ |
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257 | if( ! __atomic_load_n(&do_terminate, __ATOMIC_ACQUIRE) ) { |
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258 | __cfadbg_print_safe(runtime_core, "Kernel : core %p signaling termination\n", &this); |
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259 | |
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260 | __atomic_store_n(&do_terminate, true, __ATOMIC_RELAXED); |
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261 | __wake_proc( &this ); |
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262 | |
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263 | P( terminated ); |
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264 | verify( kernelTLS.this_processor != &this); |
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265 | } |
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266 | |
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267 | int err = pthread_join( kernel_thread, 0p ); |
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268 | if( err != 0 ) abort("KERNEL ERROR: joining processor %p caused error %s\n", &this, strerror(err)); |
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269 | |
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270 | free( this.stack ); |
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271 | |
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272 | __atomic_fetch_sub( &cltr->nprocessors, 1u, __ATOMIC_SEQ_CST ); |
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273 | } |
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274 | |
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275 | void ?{}(cluster & this, const char name[], Duration preemption_rate, unsigned io_flags) with( this ) { |
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276 | this.name = name; |
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277 | this.preemption_rate = preemption_rate; |
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278 | this.nprocessors = 0; |
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279 | ready_queue{}; |
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280 | |
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281 | #if !defined(__CFA_NO_STATISTICS__) |
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282 | print_stats = 0; |
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283 | stats = alloc(); |
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284 | __init_stats( stats ); |
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285 | #endif |
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286 | |
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287 | threads{ __get }; |
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288 | |
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289 | __kernel_io_startup( this, io_flags, &this == mainCluster ); |
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290 | |
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291 | doregister(this); |
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292 | } |
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293 | |
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294 | void ^?{}(cluster & this) { |
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295 | __kernel_io_shutdown( this, &this == mainCluster ); |
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296 | |
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297 | #if !defined(__CFA_NO_STATISTICS__) |
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298 | if( 0 != this.print_stats ) { |
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299 | __print_stats( this.stats, this.print_stats, true, this.name, (void*)&this ); |
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300 | } |
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301 | free( this.stats ); |
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302 | #endif |
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303 | |
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304 | unregister(this); |
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305 | } |
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306 | |
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307 | //============================================================================================= |
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308 | // Kernel Scheduling logic |
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309 | //============================================================================================= |
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310 | //Main of the processor contexts |
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311 | void main(processorCtx_t & runner) { |
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312 | // Because of a bug, we couldn't initialized the seed on construction |
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313 | // Do it here |
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314 | kernelTLS.rand_seed ^= rdtscl(); |
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315 | |
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316 | processor * this = runner.proc; |
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317 | verify(this); |
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318 | |
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319 | __cfadbg_print_safe(runtime_core, "Kernel : core %p starting\n", this); |
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320 | |
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321 | // register the processor unless it's the main thread which is handled in the boot sequence |
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322 | if(this != mainProcessor) { |
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323 | this->id = doregister((__processor_id_t*)this); |
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324 | #if !defined(__CFA_NO_STATISTICS__) |
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325 | if( this->print_halts ) { |
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326 | __cfaabi_bits_print_safe( STDOUT_FILENO, "Processor : %d - %s (%p)\n", this->id, this->name, (void*)this); |
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327 | } |
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328 | #endif |
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329 | |
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330 | // Lock the RWlock so no-one pushes/pops while we are changing the queue |
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331 | uint_fast32_t last_size = ready_mutate_lock(); |
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332 | |
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333 | // Adjust the ready queue size |
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334 | ready_queue_grow( this->cltr ); |
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335 | |
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336 | // Unlock the RWlock |
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337 | ready_mutate_unlock( last_size ); |
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338 | } |
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339 | |
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340 | { |
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341 | // Setup preemption data |
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342 | preemption_scope scope = { this }; |
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343 | |
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344 | __cfadbg_print_safe(runtime_core, "Kernel : core %p started\n", this); |
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345 | |
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346 | $thread * readyThread = 0p; |
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347 | for( unsigned int spin_count = 0;; spin_count++ ) { |
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348 | // Try to get the next thread |
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349 | readyThread = __next_thread( this->cltr ); |
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350 | |
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351 | // Check if we actually found a thread |
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352 | if( readyThread ) { |
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353 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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354 | /* paranoid */ verifyf( readyThread->state == Ready || readyThread->preempted != __NO_PREEMPTION, "state : %d, preempted %d\n", readyThread->state, readyThread->preempted); |
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355 | /* paranoid */ verifyf( readyThread->link.next == 0p, "Expected null got %p", readyThread->link.next ); |
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356 | __builtin_prefetch( readyThread->context.SP ); |
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357 | |
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358 | // We found a thread run it |
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359 | __run_thread(this, readyThread); |
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360 | |
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361 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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362 | } |
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363 | |
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364 | if(__atomic_load_n(&this->do_terminate, __ATOMIC_SEQ_CST)) break; |
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365 | |
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366 | if( !readyThread ) { |
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367 | // Block until a thread is ready |
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368 | __halt(this); |
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369 | } |
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370 | } |
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371 | |
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372 | __cfadbg_print_safe(runtime_core, "Kernel : core %p stopping\n", this); |
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373 | } |
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374 | |
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375 | V( this->terminated ); |
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376 | |
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377 | // unregister the processor unless it's the main thread which is handled in the boot sequence |
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378 | if(this != mainProcessor) { |
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379 | // Lock the RWlock so no-one pushes/pops while we are changing the queue |
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380 | uint_fast32_t last_size = ready_mutate_lock(); |
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381 | |
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382 | // Adjust the ready queue size |
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383 | ready_queue_shrink( this->cltr ); |
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384 | |
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385 | // Make sure we aren't on the idle queue |
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386 | #if !defined(__CFA_NO_STATISTICS__) |
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387 | bool removed = |
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388 | #endif |
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389 | unsafe_remove( this->cltr->idles, this ); |
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390 | |
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391 | #if !defined(__CFA_NO_STATISTICS__) |
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392 | if(removed) __tls_stats()->ready.sleep.exits++; |
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393 | #endif |
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394 | |
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395 | // Unlock the RWlock |
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396 | ready_mutate_unlock( last_size ); |
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397 | |
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398 | // Finally we don't need the read_lock any more |
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399 | unregister((__processor_id_t*)this); |
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400 | } |
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401 | else { |
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402 | // HACK : the coroutine context switch expects this_thread to be set |
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403 | // and it make sense for it to be set in all other cases except here |
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404 | // fake it |
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405 | kernelTLS.this_thread = mainThread; |
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406 | } |
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407 | |
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408 | __cfadbg_print_safe(runtime_core, "Kernel : core %p terminated\n", this); |
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409 | } |
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410 | |
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411 | static int * __volatile_errno() __attribute__((noinline)); |
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412 | static int * __volatile_errno() { asm(""); return &errno; } |
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413 | |
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414 | // KERNEL ONLY |
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415 | // runThread runs a thread by context switching |
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416 | // from the processor coroutine to the target thread |
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417 | static void __run_thread(processor * this, $thread * thrd_dst) { |
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418 | $coroutine * proc_cor = get_coroutine(this->runner); |
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419 | |
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420 | // Update global state |
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421 | kernelTLS.this_thread = thrd_dst; |
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422 | |
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423 | // set state of processor coroutine to inactive |
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424 | verify(proc_cor->state == Active); |
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425 | proc_cor->state = Blocked; |
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426 | |
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427 | // Actually run the thread |
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428 | RUNNING: while(true) { |
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429 | thrd_dst->preempted = __NO_PREEMPTION; |
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430 | thrd_dst->state = Active; |
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431 | |
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432 | __cfaabi_dbg_debug_do( |
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433 | thrd_dst->park_stale = true; |
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434 | thrd_dst->unpark_stale = true; |
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435 | ) |
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436 | |
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437 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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438 | /* paranoid */ verify( kernelTLS.this_thread == thrd_dst ); |
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439 | /* 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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440 | /* 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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441 | |
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442 | // set context switch to the thread that the processor is executing |
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443 | verify( thrd_dst->context.SP ); |
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444 | __cfactx_switch( &proc_cor->context, &thrd_dst->context ); |
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445 | // when __cfactx_switch returns we are back in the processor coroutine |
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446 | |
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447 | /* 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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448 | /* 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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449 | /* paranoid */ verify( kernelTLS.this_thread == thrd_dst ); |
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450 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
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451 | |
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452 | |
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453 | // We just finished running a thread, there are a few things that could have happened. |
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454 | // 1 - Regular case : the thread has blocked and now one has scheduled it yet. |
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455 | // 2 - Racy case : the thread has blocked but someone has already tried to schedule it. |
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456 | // 4 - Preempted |
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457 | // In case 1, we may have won a race so we can't write to the state again. |
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458 | // In case 2, we lost the race so we now own the thread. |
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459 | |
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460 | if(unlikely(thrd_dst->preempted != __NO_PREEMPTION)) { |
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461 | // The thread was preempted, reschedule it and reset the flag |
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462 | __schedule_thread( (__processor_id_t*)this, thrd_dst ); |
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463 | break RUNNING; |
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464 | } |
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465 | |
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466 | if(unlikely(thrd_dst->state == Halted)) { |
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467 | // The thread has halted, it should never be scheduled/run again |
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468 | // We may need to wake someone up here since |
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469 | unpark( this->destroyer __cfaabi_dbg_ctx2 ); |
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470 | this->destroyer = 0p; |
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471 | break RUNNING; |
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472 | } |
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473 | |
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474 | /* paranoid */ verify( thrd_dst->state == Active ); |
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475 | thrd_dst->state = Blocked; |
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476 | |
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477 | // set state of processor coroutine to active and the thread to inactive |
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478 | int old_ticket = __atomic_fetch_sub(&thrd_dst->ticket, 1, __ATOMIC_SEQ_CST); |
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479 | __cfaabi_dbg_debug_do( thrd_dst->park_result = old_ticket; ) |
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480 | switch(old_ticket) { |
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481 | case 1: |
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482 | // This is case 1, the regular case, nothing more is needed |
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483 | break RUNNING; |
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484 | case 2: |
---|
485 | // This is case 2, the racy case, someone tried to run this thread before it finished blocking |
---|
486 | // In this case, just run it again. |
---|
487 | continue RUNNING; |
---|
488 | default: |
---|
489 | // This makes no sense, something is wrong abort |
---|
490 | abort(); |
---|
491 | } |
---|
492 | } |
---|
493 | |
---|
494 | // Just before returning to the processor, set the processor coroutine to active |
---|
495 | proc_cor->state = Active; |
---|
496 | kernelTLS.this_thread = 0p; |
---|
497 | } |
---|
498 | |
---|
499 | // KERNEL_ONLY |
---|
500 | void returnToKernel() { |
---|
501 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
502 | $coroutine * proc_cor = get_coroutine(kernelTLS.this_processor->runner); |
---|
503 | $thread * thrd_src = kernelTLS.this_thread; |
---|
504 | |
---|
505 | #if !defined(__CFA_NO_STATISTICS__) |
---|
506 | struct processor * last_proc = kernelTLS.this_processor; |
---|
507 | #endif |
---|
508 | |
---|
509 | // Run the thread on this processor |
---|
510 | { |
---|
511 | int local_errno = *__volatile_errno(); |
---|
512 | #if defined( __i386 ) || defined( __x86_64 ) |
---|
513 | __x87_store; |
---|
514 | #endif |
---|
515 | verify( proc_cor->context.SP ); |
---|
516 | __cfactx_switch( &thrd_src->context, &proc_cor->context ); |
---|
517 | #if defined( __i386 ) || defined( __x86_64 ) |
---|
518 | __x87_load; |
---|
519 | #endif |
---|
520 | *__volatile_errno() = local_errno; |
---|
521 | } |
---|
522 | |
---|
523 | #if !defined(__CFA_NO_STATISTICS__) |
---|
524 | if(last_proc != kernelTLS.this_processor) { |
---|
525 | __tls_stats()->ready.threads.migration++; |
---|
526 | } |
---|
527 | #endif |
---|
528 | |
---|
529 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
530 | /* 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 ); |
---|
531 | /* 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 ); |
---|
532 | } |
---|
533 | |
---|
534 | // KERNEL_ONLY |
---|
535 | // Context invoker for processors |
---|
536 | // This is the entry point for processors (kernel threads) |
---|
537 | // It effectively constructs a coroutine by stealing the pthread stack |
---|
538 | static void * __invoke_processor(void * arg) { |
---|
539 | #if !defined( __CFA_NO_STATISTICS__ ) |
---|
540 | __stats_t local_stats; |
---|
541 | __init_stats( &local_stats ); |
---|
542 | kernelTLS.this_stats = &local_stats; |
---|
543 | #endif |
---|
544 | |
---|
545 | processor * proc = (processor *) arg; |
---|
546 | kernelTLS.this_processor = proc; |
---|
547 | kernelTLS.this_thread = 0p; |
---|
548 | kernelTLS.preemption_state.[enabled, disable_count] = [false, 1]; |
---|
549 | // SKULLDUGGERY: We want to create a context for the processor coroutine |
---|
550 | // which is needed for the 2-step context switch. However, there is no reason |
---|
551 | // to waste the perfectly valid stack create by pthread. |
---|
552 | current_stack_info_t info; |
---|
553 | __stack_t ctx; |
---|
554 | info.storage = &ctx; |
---|
555 | (proc->runner){ proc, &info }; |
---|
556 | |
---|
557 | __cfaabi_dbg_print_safe("Coroutine : created stack %p\n", get_coroutine(proc->runner)->stack.storage); |
---|
558 | |
---|
559 | //Set global state |
---|
560 | kernelTLS.this_thread = 0p; |
---|
561 | |
---|
562 | //We now have a proper context from which to schedule threads |
---|
563 | __cfadbg_print_safe(runtime_core, "Kernel : core %p created (%p, %p)\n", proc, &proc->runner, &ctx); |
---|
564 | |
---|
565 | // SKULLDUGGERY: Since the coroutine doesn't have its own stack, we can't |
---|
566 | // resume it to start it like it normally would, it will just context switch |
---|
567 | // back to here. Instead directly call the main since we already are on the |
---|
568 | // appropriate stack. |
---|
569 | get_coroutine(proc->runner)->state = Active; |
---|
570 | main( proc->runner ); |
---|
571 | get_coroutine(proc->runner)->state = Halted; |
---|
572 | |
---|
573 | // Main routine of the core returned, the core is now fully terminated |
---|
574 | __cfadbg_print_safe(runtime_core, "Kernel : core %p main ended (%p)\n", proc, &proc->runner); |
---|
575 | |
---|
576 | #if !defined(__CFA_NO_STATISTICS__) |
---|
577 | __tally_stats(proc->cltr->stats, &local_stats); |
---|
578 | if( 0 != proc->print_stats ) { |
---|
579 | __print_stats( &local_stats, proc->print_stats, true, proc->name, (void*)proc ); |
---|
580 | } |
---|
581 | #endif |
---|
582 | |
---|
583 | return 0p; |
---|
584 | } |
---|
585 | |
---|
586 | static void Abort( int ret, const char func[] ) { |
---|
587 | if ( ret ) { // pthread routines return errno values |
---|
588 | abort( "%s : internal error, error(%d) %s.", func, ret, strerror( ret ) ); |
---|
589 | } // if |
---|
590 | } // Abort |
---|
591 | |
---|
592 | void * __create_pthread( pthread_t * pthread, void * (*start)(void *), void * arg ) { |
---|
593 | pthread_attr_t attr; |
---|
594 | |
---|
595 | Abort( pthread_attr_init( &attr ), "pthread_attr_init" ); // initialize attribute |
---|
596 | |
---|
597 | size_t stacksize; |
---|
598 | // default stack size, normally defined by shell limit |
---|
599 | Abort( pthread_attr_getstacksize( &attr, &stacksize ), "pthread_attr_getstacksize" ); |
---|
600 | assert( stacksize >= PTHREAD_STACK_MIN ); |
---|
601 | |
---|
602 | void * stack; |
---|
603 | __cfaabi_dbg_debug_do( |
---|
604 | stack = memalign( __page_size, stacksize + __page_size ); |
---|
605 | // pthread has no mechanism to create the guard page in user supplied stack. |
---|
606 | if ( mprotect( stack, __page_size, PROT_NONE ) == -1 ) { |
---|
607 | abort( "mprotect : internal error, mprotect failure, error(%d) %s.", errno, strerror( errno ) ); |
---|
608 | } // if |
---|
609 | ); |
---|
610 | __cfaabi_dbg_no_debug_do( |
---|
611 | stack = malloc( stacksize ); |
---|
612 | ); |
---|
613 | |
---|
614 | Abort( pthread_attr_setstack( &attr, stack, stacksize ), "pthread_attr_setstack" ); |
---|
615 | |
---|
616 | Abort( pthread_create( pthread, &attr, start, arg ), "pthread_create" ); |
---|
617 | return stack; |
---|
618 | } |
---|
619 | |
---|
620 | // KERNEL_ONLY |
---|
621 | static void __kernel_first_resume( processor * this ) { |
---|
622 | $thread * src = mainThread; |
---|
623 | $coroutine * dst = get_coroutine(this->runner); |
---|
624 | |
---|
625 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
626 | |
---|
627 | kernelTLS.this_thread->curr_cor = dst; |
---|
628 | __stack_prepare( &dst->stack, 65000 ); |
---|
629 | __cfactx_start(main, dst, this->runner, __cfactx_invoke_coroutine); |
---|
630 | |
---|
631 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
632 | |
---|
633 | dst->last = &src->self_cor; |
---|
634 | dst->starter = dst->starter ? dst->starter : &src->self_cor; |
---|
635 | |
---|
636 | // make sure the current state is still correct |
---|
637 | /* paranoid */ verify(src->state == Ready); |
---|
638 | |
---|
639 | // context switch to specified coroutine |
---|
640 | verify( dst->context.SP ); |
---|
641 | __cfactx_switch( &src->context, &dst->context ); |
---|
642 | // when __cfactx_switch returns we are back in the src coroutine |
---|
643 | |
---|
644 | mainThread->curr_cor = &mainThread->self_cor; |
---|
645 | |
---|
646 | // make sure the current state has been update |
---|
647 | /* paranoid */ verify(src->state == Active); |
---|
648 | |
---|
649 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
650 | } |
---|
651 | |
---|
652 | // KERNEL_ONLY |
---|
653 | static void __kernel_last_resume( processor * this ) { |
---|
654 | $coroutine * src = &mainThread->self_cor; |
---|
655 | $coroutine * dst = get_coroutine(this->runner); |
---|
656 | |
---|
657 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
658 | verify( dst->starter == src ); |
---|
659 | verify( dst->context.SP ); |
---|
660 | |
---|
661 | // SKULLDUGGERY in debug the processors check that the |
---|
662 | // stack is still within the limit of the stack limits after running a thread. |
---|
663 | // that check doesn't make sense if we context switch to the processor using the |
---|
664 | // coroutine semantics. Since this is a special case, use the current context |
---|
665 | // info to populate these fields. |
---|
666 | __cfaabi_dbg_debug_do( |
---|
667 | __stack_context_t ctx; |
---|
668 | CtxGet( ctx ); |
---|
669 | mainThread->context.SP = ctx.SP; |
---|
670 | mainThread->context.FP = ctx.FP; |
---|
671 | ) |
---|
672 | |
---|
673 | // context switch to the processor |
---|
674 | __cfactx_switch( &src->context, &dst->context ); |
---|
675 | } |
---|
676 | |
---|
677 | //----------------------------------------------------------------------------- |
---|
678 | // Scheduler routines |
---|
679 | // KERNEL ONLY |
---|
680 | void __schedule_thread( struct __processor_id_t * id, $thread * thrd ) { |
---|
681 | /* paranoid */ verify( thrd ); |
---|
682 | /* paranoid */ verify( thrd->state != Halted ); |
---|
683 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
684 | /* paranoid */ #if defined( __CFA_WITH_VERIFY__ ) |
---|
685 | /* paranoid */ if( thrd->state == Blocked || thrd->state == Start ) assertf( thrd->preempted == __NO_PREEMPTION, |
---|
686 | "Error inactive thread marked as preempted, state %d, preemption %d\n", thrd->state, thrd->preempted ); |
---|
687 | /* paranoid */ if( thrd->preempted != __NO_PREEMPTION ) assertf(thrd->state == Active, |
---|
688 | "Error preempted thread marked as not currently running, state %d, preemption %d\n", thrd->state, thrd->preempted ); |
---|
689 | /* paranoid */ #endif |
---|
690 | /* paranoid */ verifyf( thrd->link.next == 0p, "Expected null got %p", thrd->link.next ); |
---|
691 | |
---|
692 | if (thrd->preempted == __NO_PREEMPTION) thrd->state = Ready; |
---|
693 | |
---|
694 | ready_schedule_lock ( id ); |
---|
695 | push( thrd->curr_cluster, thrd ); |
---|
696 | |
---|
697 | #if !defined(__CFA_NO_STATISTICS__) |
---|
698 | bool woke = |
---|
699 | #endif |
---|
700 | __wake_one(id, thrd->curr_cluster); |
---|
701 | |
---|
702 | #if !defined(__CFA_NO_STATISTICS__) |
---|
703 | if(woke) __tls_stats()->ready.sleep.wakes++; |
---|
704 | #endif |
---|
705 | ready_schedule_unlock( id ); |
---|
706 | |
---|
707 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
708 | } |
---|
709 | |
---|
710 | // KERNEL ONLY |
---|
711 | static $thread * __next_thread(cluster * this) with( *this ) { |
---|
712 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
713 | |
---|
714 | ready_schedule_lock ( (__processor_id_t*)kernelTLS.this_processor ); |
---|
715 | $thread * head = pop( this ); |
---|
716 | ready_schedule_unlock( (__processor_id_t*)kernelTLS.this_processor ); |
---|
717 | |
---|
718 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
719 | return head; |
---|
720 | } |
---|
721 | |
---|
722 | // KERNEL ONLY |
---|
723 | static bool __has_next_thread(cluster * this) with( *this ) { |
---|
724 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
725 | |
---|
726 | ready_schedule_lock ( (__processor_id_t*)kernelTLS.this_processor ); |
---|
727 | bool not_empty = query( this ); |
---|
728 | ready_schedule_unlock( (__processor_id_t*)kernelTLS.this_processor ); |
---|
729 | |
---|
730 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
731 | return not_empty; |
---|
732 | } |
---|
733 | |
---|
734 | // KERNEL ONLY unpark with out disabling interrupts |
---|
735 | void __unpark( struct __processor_id_t * id, $thread * thrd __cfaabi_dbg_ctx_param2 ) { |
---|
736 | // record activity |
---|
737 | __cfaabi_dbg_record_thrd( *thrd, false, caller ); |
---|
738 | |
---|
739 | int old_ticket = __atomic_fetch_add(&thrd->ticket, 1, __ATOMIC_SEQ_CST); |
---|
740 | __cfaabi_dbg_debug_do( thrd->unpark_result = old_ticket; thrd->unpark_state = thrd->state; ) |
---|
741 | switch(old_ticket) { |
---|
742 | case 1: |
---|
743 | // Wake won the race, the thread will reschedule/rerun itself |
---|
744 | break; |
---|
745 | case 0: |
---|
746 | /* paranoid */ verify( ! thrd->preempted != __NO_PREEMPTION ); |
---|
747 | /* paranoid */ verify( thrd->state == Blocked ); |
---|
748 | |
---|
749 | // Wake lost the race, |
---|
750 | __schedule_thread( id, thrd ); |
---|
751 | break; |
---|
752 | default: |
---|
753 | // This makes no sense, something is wrong abort |
---|
754 | abort(); |
---|
755 | } |
---|
756 | } |
---|
757 | |
---|
758 | void unpark( $thread * thrd __cfaabi_dbg_ctx_param2 ) { |
---|
759 | if( !thrd ) return; |
---|
760 | |
---|
761 | disable_interrupts(); |
---|
762 | __unpark( (__processor_id_t*)kernelTLS.this_processor, thrd __cfaabi_dbg_ctx_fwd2 ); |
---|
763 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
764 | } |
---|
765 | |
---|
766 | void park( __cfaabi_dbg_ctx_param ) { |
---|
767 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
768 | disable_interrupts(); |
---|
769 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
770 | /* paranoid */ verify( kernelTLS.this_thread->preempted == __NO_PREEMPTION ); |
---|
771 | |
---|
772 | // record activity |
---|
773 | __cfaabi_dbg_record_thrd( *kernelTLS.this_thread, true, caller ); |
---|
774 | |
---|
775 | returnToKernel(); |
---|
776 | |
---|
777 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
778 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
779 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
780 | |
---|
781 | } |
---|
782 | |
---|
783 | // KERNEL ONLY |
---|
784 | void __leave_thread() { |
---|
785 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
786 | returnToKernel(); |
---|
787 | abort(); |
---|
788 | } |
---|
789 | |
---|
790 | // KERNEL ONLY |
---|
791 | bool force_yield( __Preemption_Reason reason ) { |
---|
792 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
793 | disable_interrupts(); |
---|
794 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
795 | |
---|
796 | $thread * thrd = kernelTLS.this_thread; |
---|
797 | /* paranoid */ verify(thrd->state == Active); |
---|
798 | |
---|
799 | // SKULLDUGGERY: It is possible that we are preempting this thread just before |
---|
800 | // it was going to park itself. If that is the case and it is already using the |
---|
801 | // intrusive fields then we can't use them to preempt the thread |
---|
802 | // If that is the case, abandon the preemption. |
---|
803 | bool preempted = false; |
---|
804 | if(thrd->link.next == 0p) { |
---|
805 | preempted = true; |
---|
806 | thrd->preempted = reason; |
---|
807 | returnToKernel(); |
---|
808 | } |
---|
809 | |
---|
810 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
811 | enable_interrupts_noPoll(); |
---|
812 | /* paranoid */ verify( kernelTLS.preemption_state.enabled ); |
---|
813 | |
---|
814 | return preempted; |
---|
815 | } |
---|
816 | |
---|
817 | //============================================================================================= |
---|
818 | // Kernel Setup logic |
---|
819 | //============================================================================================= |
---|
820 | //----------------------------------------------------------------------------- |
---|
821 | // Kernel boot procedures |
---|
822 | static void __kernel_startup(void) { |
---|
823 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
824 | __cfadbg_print_safe(runtime_core, "Kernel : Starting\n"); |
---|
825 | |
---|
826 | __page_size = sysconf( _SC_PAGESIZE ); |
---|
827 | |
---|
828 | __cfa_dbg_global_clusters.list{ __get }; |
---|
829 | __cfa_dbg_global_clusters.lock{}; |
---|
830 | |
---|
831 | // Initialize the global scheduler lock |
---|
832 | __scheduler_lock = (__scheduler_RWLock_t*)&storage___scheduler_lock; |
---|
833 | (*__scheduler_lock){}; |
---|
834 | |
---|
835 | // Initialize the main cluster |
---|
836 | mainCluster = (cluster *)&storage_mainCluster; |
---|
837 | (*mainCluster){"Main Cluster"}; |
---|
838 | |
---|
839 | __cfadbg_print_safe(runtime_core, "Kernel : Main cluster ready\n"); |
---|
840 | |
---|
841 | // Start by initializing the main thread |
---|
842 | // SKULLDUGGERY: the mainThread steals the process main thread |
---|
843 | // which will then be scheduled by the mainProcessor normally |
---|
844 | mainThread = ($thread *)&storage_mainThread; |
---|
845 | current_stack_info_t info; |
---|
846 | info.storage = (__stack_t*)&storage_mainThreadCtx; |
---|
847 | (*mainThread){ &info }; |
---|
848 | |
---|
849 | __cfadbg_print_safe(runtime_core, "Kernel : Main thread ready\n"); |
---|
850 | |
---|
851 | |
---|
852 | |
---|
853 | // Construct the processor context of the main processor |
---|
854 | void ?{}(processorCtx_t & this, processor * proc) { |
---|
855 | (this.__cor){ "Processor" }; |
---|
856 | this.__cor.starter = 0p; |
---|
857 | this.proc = proc; |
---|
858 | } |
---|
859 | |
---|
860 | void ?{}(processor & this) with( this ) { |
---|
861 | name = "Main Processor"; |
---|
862 | cltr = mainCluster; |
---|
863 | terminated{ 0 }; |
---|
864 | do_terminate = false; |
---|
865 | preemption_alarm = 0p; |
---|
866 | pending_preemption = false; |
---|
867 | kernel_thread = pthread_self(); |
---|
868 | id = -1u; |
---|
869 | |
---|
870 | #if !defined(__CFA_NO_STATISTICS__) |
---|
871 | print_stats = false; |
---|
872 | print_halts = false; |
---|
873 | #endif |
---|
874 | |
---|
875 | runner{ &this }; |
---|
876 | __cfadbg_print_safe(runtime_core, "Kernel : constructed main processor context %p\n", &runner); |
---|
877 | |
---|
878 | __atomic_fetch_add( &cltr->nprocessors, 1u, __ATOMIC_SEQ_CST ); |
---|
879 | } |
---|
880 | |
---|
881 | // Initialize the main processor and the main processor ctx |
---|
882 | // (the coroutine that contains the processing control flow) |
---|
883 | mainProcessor = (processor *)&storage_mainProcessor; |
---|
884 | (*mainProcessor){}; |
---|
885 | |
---|
886 | mainProcessor->id = doregister( (__processor_id_t*)mainProcessor); |
---|
887 | |
---|
888 | //initialize the global state variables |
---|
889 | kernelTLS.this_processor = mainProcessor; |
---|
890 | kernelTLS.this_thread = mainThread; |
---|
891 | |
---|
892 | #if !defined( __CFA_NO_STATISTICS__ ) |
---|
893 | kernelTLS.this_stats = (__stats_t *)& storage_mainProcStats; |
---|
894 | __init_stats( kernelTLS.this_stats ); |
---|
895 | #endif |
---|
896 | |
---|
897 | // Enable preemption |
---|
898 | kernel_start_preemption(); |
---|
899 | |
---|
900 | // Add the main thread to the ready queue |
---|
901 | // once resume is called on mainProcessor->runner the mainThread needs to be scheduled like any normal thread |
---|
902 | __schedule_thread((__processor_id_t *)mainProcessor, mainThread); |
---|
903 | |
---|
904 | // SKULLDUGGERY: Force a context switch to the main processor to set the main thread's context to the current UNIX |
---|
905 | // context. Hence, the main thread does not begin through __cfactx_invoke_thread, like all other threads. The trick here is that |
---|
906 | // mainThread is on the ready queue when this call is made. |
---|
907 | __kernel_first_resume( kernelTLS.this_processor ); |
---|
908 | |
---|
909 | |
---|
910 | // THE SYSTEM IS NOW COMPLETELY RUNNING |
---|
911 | |
---|
912 | |
---|
913 | // Now that the system is up, finish creating systems that need threading |
---|
914 | __kernel_io_finish_start( *mainCluster ); |
---|
915 | |
---|
916 | |
---|
917 | __cfadbg_print_safe(runtime_core, "Kernel : Started\n--------------------------------------------------\n\n"); |
---|
918 | |
---|
919 | verify( ! kernelTLS.preemption_state.enabled ); |
---|
920 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
921 | verify( TL_GET( preemption_state.enabled ) ); |
---|
922 | } |
---|
923 | |
---|
924 | static void __kernel_shutdown(void) { |
---|
925 | //Before we start shutting things down, wait for systems that need threading to shutdown |
---|
926 | __kernel_io_prepare_stop( *mainCluster ); |
---|
927 | |
---|
928 | /* paranoid */ verify( TL_GET( preemption_state.enabled ) ); |
---|
929 | disable_interrupts(); |
---|
930 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
931 | |
---|
932 | __cfadbg_print_safe(runtime_core, "\n--------------------------------------------------\nKernel : Shutting down\n"); |
---|
933 | |
---|
934 | // SKULLDUGGERY: Notify the mainProcessor it needs to terminates. |
---|
935 | // When its coroutine terminates, it return control to the mainThread |
---|
936 | // which is currently here |
---|
937 | __atomic_store_n(&mainProcessor->do_terminate, true, __ATOMIC_RELEASE); |
---|
938 | __kernel_last_resume( kernelTLS.this_processor ); |
---|
939 | mainThread->self_cor.state = Halted; |
---|
940 | |
---|
941 | // THE SYSTEM IS NOW COMPLETELY STOPPED |
---|
942 | |
---|
943 | // Disable preemption |
---|
944 | kernel_stop_preemption(); |
---|
945 | |
---|
946 | unregister((__processor_id_t*)mainProcessor); |
---|
947 | |
---|
948 | // Destroy the main processor and its context in reverse order of construction |
---|
949 | // These were manually constructed so we need manually destroy them |
---|
950 | void ^?{}(processor & this) with( this ){ |
---|
951 | /* paranoid */ verify( this.do_terminate == true ); |
---|
952 | __atomic_fetch_sub( &cltr->nprocessors, 1u, __ATOMIC_SEQ_CST ); |
---|
953 | __cfaabi_dbg_print_safe("Kernel : destroyed main processor context %p\n", &runner); |
---|
954 | } |
---|
955 | |
---|
956 | ^(*mainProcessor){}; |
---|
957 | |
---|
958 | // Final step, destroy the main thread since it is no longer needed |
---|
959 | |
---|
960 | // Since we provided a stack to this taxk it will not destroy anything |
---|
961 | /* paranoid */ verify(mainThread->self_cor.stack.storage == (__stack_t*)(((uintptr_t)&storage_mainThreadCtx)| 0x1)); |
---|
962 | ^(*mainThread){}; |
---|
963 | |
---|
964 | ^(*mainCluster){}; |
---|
965 | |
---|
966 | ^(*__scheduler_lock){}; |
---|
967 | |
---|
968 | ^(__cfa_dbg_global_clusters.list){}; |
---|
969 | ^(__cfa_dbg_global_clusters.lock){}; |
---|
970 | |
---|
971 | __cfadbg_print_safe(runtime_core, "Kernel : Shutdown complete\n"); |
---|
972 | } |
---|
973 | |
---|
974 | //============================================================================================= |
---|
975 | // Kernel Idle Sleep |
---|
976 | //============================================================================================= |
---|
977 | // Wake a thread from the front if there are any |
---|
978 | static bool __wake_one(struct __processor_id_t * id, cluster * this) { |
---|
979 | /* paranoid */ verify( ready_schedule_islocked( id ) ); |
---|
980 | |
---|
981 | // Check if there is a sleeping processor |
---|
982 | processor * p = pop(this->idles); |
---|
983 | |
---|
984 | // If no one is sleeping, we are done |
---|
985 | if( 0p == p ) return false; |
---|
986 | |
---|
987 | // We found a processor, wake it up |
---|
988 | post( p->idle ); |
---|
989 | |
---|
990 | return true; |
---|
991 | } |
---|
992 | |
---|
993 | // Unconditionnaly wake a thread |
---|
994 | static bool __wake_proc(processor * this) { |
---|
995 | __cfadbg_print_safe(runtime_core, "Kernel : waking Processor %p\n", this); |
---|
996 | |
---|
997 | disable_interrupts(); |
---|
998 | /* paranoid */ verify( ! kernelTLS.preemption_state.enabled ); |
---|
999 | bool ret = post( this->idle ); |
---|
1000 | enable_interrupts( __cfaabi_dbg_ctx ); |
---|
1001 | |
---|
1002 | return ret; |
---|
1003 | } |
---|
1004 | |
---|
1005 | static void __halt(processor * this) with( *this ) { |
---|
1006 | if( do_terminate ) return; |
---|
1007 | |
---|
1008 | #if !defined(__CFA_NO_STATISTICS__) |
---|
1009 | __tls_stats()->ready.sleep.halts++; |
---|
1010 | #endif |
---|
1011 | // Push self to queue |
---|
1012 | push(cltr->idles, *this); |
---|
1013 | |
---|
1014 | // Makre sure we don't miss a thread |
---|
1015 | if( __has_next_thread(cltr) ) { |
---|
1016 | // A thread was posted, make sure a processor is woken up |
---|
1017 | struct __processor_id_t *id = (struct __processor_id_t *) this; |
---|
1018 | ready_schedule_lock ( id ); |
---|
1019 | __wake_one( id, cltr ); |
---|
1020 | ready_schedule_unlock( id ); |
---|
1021 | #if !defined(__CFA_NO_STATISTICS__) |
---|
1022 | __tls_stats()->ready.sleep.cancels++; |
---|
1023 | #endif |
---|
1024 | } |
---|
1025 | |
---|
1026 | #if !defined(__CFA_NO_STATISTICS__) |
---|
1027 | if(this->print_halts) { |
---|
1028 | __cfaabi_bits_print_safe( STDOUT_FILENO, "PH:%d - %lld 0\n", this->id, rdtscl()); |
---|
1029 | } |
---|
1030 | #endif |
---|
1031 | |
---|
1032 | wait( idle ); |
---|
1033 | |
---|
1034 | #if !defined(__CFA_NO_STATISTICS__) |
---|
1035 | if(this->print_halts) { |
---|
1036 | __cfaabi_bits_print_safe( STDOUT_FILENO, "PH:%d - %lld 1\n", this->id, rdtscl()); |
---|
1037 | } |
---|
1038 | #endif |
---|
1039 | } |
---|
1040 | |
---|
1041 | //============================================================================================= |
---|
1042 | // Unexpected Terminating logic |
---|
1043 | //============================================================================================= |
---|
1044 | static __spinlock_t kernel_abort_lock; |
---|
1045 | static bool kernel_abort_called = false; |
---|
1046 | |
---|
1047 | void * kernel_abort(void) __attribute__ ((__nothrow__)) { |
---|
1048 | // abort cannot be recursively entered by the same or different processors because all signal handlers return when |
---|
1049 | // the globalAbort flag is true. |
---|
1050 | lock( kernel_abort_lock __cfaabi_dbg_ctx2 ); |
---|
1051 | |
---|
1052 | // first task to abort ? |
---|
1053 | if ( kernel_abort_called ) { // not first task to abort ? |
---|
1054 | unlock( kernel_abort_lock ); |
---|
1055 | |
---|
1056 | sigset_t mask; |
---|
1057 | sigemptyset( &mask ); |
---|
1058 | sigaddset( &mask, SIGALRM ); // block SIGALRM signals |
---|
1059 | sigaddset( &mask, SIGUSR1 ); // block SIGALRM signals |
---|
1060 | sigsuspend( &mask ); // block the processor to prevent further damage during abort |
---|
1061 | _exit( EXIT_FAILURE ); // if processor unblocks before it is killed, terminate it |
---|
1062 | } |
---|
1063 | else { |
---|
1064 | kernel_abort_called = true; |
---|
1065 | unlock( kernel_abort_lock ); |
---|
1066 | } |
---|
1067 | |
---|
1068 | return kernelTLS.this_thread; |
---|
1069 | } |
---|
1070 | |
---|
1071 | void kernel_abort_msg( void * kernel_data, char * abort_text, int abort_text_size ) { |
---|
1072 | $thread * thrd = kernel_data; |
---|
1073 | |
---|
1074 | if(thrd) { |
---|
1075 | int len = snprintf( abort_text, abort_text_size, "Error occurred while executing thread %.256s (%p)", thrd->self_cor.name, thrd ); |
---|
1076 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
---|
1077 | |
---|
1078 | if ( &thrd->self_cor != thrd->curr_cor ) { |
---|
1079 | len = snprintf( abort_text, abort_text_size, " in coroutine %.256s (%p).\n", thrd->curr_cor->name, thrd->curr_cor ); |
---|
1080 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
---|
1081 | } |
---|
1082 | else { |
---|
1083 | __cfaabi_bits_write( STDERR_FILENO, ".\n", 2 ); |
---|
1084 | } |
---|
1085 | } |
---|
1086 | else { |
---|
1087 | int len = snprintf( abort_text, abort_text_size, "Error occurred outside of any thread.\n" ); |
---|
1088 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
---|
1089 | } |
---|
1090 | } |
---|
1091 | |
---|
1092 | int kernel_abort_lastframe( void ) __attribute__ ((__nothrow__)) { |
---|
1093 | return get_coroutine(kernelTLS.this_thread) == get_coroutine(mainThread) ? 4 : 2; |
---|
1094 | } |
---|
1095 | |
---|
1096 | static __spinlock_t kernel_debug_lock; |
---|
1097 | |
---|
1098 | extern "C" { |
---|
1099 | void __cfaabi_bits_acquire() { |
---|
1100 | lock( kernel_debug_lock __cfaabi_dbg_ctx2 ); |
---|
1101 | } |
---|
1102 | |
---|
1103 | void __cfaabi_bits_release() { |
---|
1104 | unlock( kernel_debug_lock ); |
---|
1105 | } |
---|
1106 | } |
---|
1107 | |
---|
1108 | //============================================================================================= |
---|
1109 | // Kernel Utilities |
---|
1110 | //============================================================================================= |
---|
1111 | //----------------------------------------------------------------------------- |
---|
1112 | // Locks |
---|
1113 | void ?{}( semaphore & this, int count = 1 ) { |
---|
1114 | (this.lock){}; |
---|
1115 | this.count = count; |
---|
1116 | (this.waiting){}; |
---|
1117 | } |
---|
1118 | void ^?{}(semaphore & this) {} |
---|
1119 | |
---|
1120 | bool P(semaphore & this) with( this ){ |
---|
1121 | lock( lock __cfaabi_dbg_ctx2 ); |
---|
1122 | count -= 1; |
---|
1123 | if ( count < 0 ) { |
---|
1124 | // queue current task |
---|
1125 | append( waiting, kernelTLS.this_thread ); |
---|
1126 | |
---|
1127 | // atomically release spin lock and block |
---|
1128 | unlock( lock ); |
---|
1129 | park( __cfaabi_dbg_ctx ); |
---|
1130 | return true; |
---|
1131 | } |
---|
1132 | else { |
---|
1133 | unlock( lock ); |
---|
1134 | return false; |
---|
1135 | } |
---|
1136 | } |
---|
1137 | |
---|
1138 | bool V(semaphore & this) with( this ) { |
---|
1139 | $thread * thrd = 0p; |
---|
1140 | lock( lock __cfaabi_dbg_ctx2 ); |
---|
1141 | count += 1; |
---|
1142 | if ( count <= 0 ) { |
---|
1143 | // remove task at head of waiting list |
---|
1144 | thrd = pop_head( waiting ); |
---|
1145 | } |
---|
1146 | |
---|
1147 | unlock( lock ); |
---|
1148 | |
---|
1149 | // make new owner |
---|
1150 | unpark( thrd __cfaabi_dbg_ctx2 ); |
---|
1151 | |
---|
1152 | return thrd != 0p; |
---|
1153 | } |
---|
1154 | |
---|
1155 | bool V(semaphore & this, unsigned diff) with( this ) { |
---|
1156 | $thread * thrd = 0p; |
---|
1157 | lock( lock __cfaabi_dbg_ctx2 ); |
---|
1158 | int release = max(-count, (int)diff); |
---|
1159 | count += diff; |
---|
1160 | for(release) { |
---|
1161 | unpark( pop_head( waiting ) __cfaabi_dbg_ctx2 ); |
---|
1162 | } |
---|
1163 | |
---|
1164 | unlock( lock ); |
---|
1165 | |
---|
1166 | return thrd != 0p; |
---|
1167 | } |
---|
1168 | |
---|
1169 | //----------------------------------------------------------------------------- |
---|
1170 | // Global Queues |
---|
1171 | void doregister( cluster & cltr ) { |
---|
1172 | lock ( __cfa_dbg_global_clusters.lock __cfaabi_dbg_ctx2); |
---|
1173 | push_front( __cfa_dbg_global_clusters.list, cltr ); |
---|
1174 | unlock ( __cfa_dbg_global_clusters.lock ); |
---|
1175 | } |
---|
1176 | |
---|
1177 | void unregister( cluster & cltr ) { |
---|
1178 | lock ( __cfa_dbg_global_clusters.lock __cfaabi_dbg_ctx2); |
---|
1179 | remove( __cfa_dbg_global_clusters.list, cltr ); |
---|
1180 | unlock( __cfa_dbg_global_clusters.lock ); |
---|
1181 | } |
---|
1182 | |
---|
1183 | void doregister( cluster * cltr, $thread & thrd ) { |
---|
1184 | lock (cltr->thread_list_lock __cfaabi_dbg_ctx2); |
---|
1185 | cltr->nthreads += 1; |
---|
1186 | push_front(cltr->threads, thrd); |
---|
1187 | unlock (cltr->thread_list_lock); |
---|
1188 | } |
---|
1189 | |
---|
1190 | void unregister( cluster * cltr, $thread & thrd ) { |
---|
1191 | lock (cltr->thread_list_lock __cfaabi_dbg_ctx2); |
---|
1192 | remove(cltr->threads, thrd ); |
---|
1193 | cltr->nthreads -= 1; |
---|
1194 | unlock(cltr->thread_list_lock); |
---|
1195 | } |
---|
1196 | |
---|
1197 | //----------------------------------------------------------------------------- |
---|
1198 | // Debug |
---|
1199 | __cfaabi_dbg_debug_do( |
---|
1200 | extern "C" { |
---|
1201 | void __cfaabi_dbg_record_lock(__spinlock_t & this, const char prev_name[]) { |
---|
1202 | this.prev_name = prev_name; |
---|
1203 | this.prev_thrd = kernelTLS.this_thread; |
---|
1204 | } |
---|
1205 | |
---|
1206 | void __cfaabi_dbg_record_thrd($thread & this, bool park, const char prev_name[]) { |
---|
1207 | if(park) { |
---|
1208 | this.park_caller = prev_name; |
---|
1209 | this.park_stale = false; |
---|
1210 | } |
---|
1211 | else { |
---|
1212 | this.unpark_caller = prev_name; |
---|
1213 | this.unpark_stale = false; |
---|
1214 | } |
---|
1215 | } |
---|
1216 | } |
---|
1217 | ) |
---|
1218 | |
---|
1219 | //----------------------------------------------------------------------------- |
---|
1220 | // Debug |
---|
1221 | bool threading_enabled(void) __attribute__((const)) { |
---|
1222 | return true; |
---|
1223 | } |
---|
1224 | |
---|
1225 | //----------------------------------------------------------------------------- |
---|
1226 | // Statistics |
---|
1227 | #if !defined(__CFA_NO_STATISTICS__) |
---|
1228 | void print_halts( processor & this ) { |
---|
1229 | this.print_halts = true; |
---|
1230 | } |
---|
1231 | #endif |
---|
1232 | // Local Variables: // |
---|
1233 | // mode: c // |
---|
1234 | // tab-width: 4 // |
---|
1235 | // End: // |
---|