1 | // |
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2 | // Cforall Version 1.0.0 Copyright (C) 2019 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 | // ready_queue.cfa -- |
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8 | // |
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9 | // Author : Thierry Delisle |
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10 | // Created On : Mon Nov dd 16:29:18 2019 |
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11 | // Last Modified By : |
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12 | // Last Modified On : |
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13 | // Update Count : |
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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_READY_QUEUE__ |
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18 | |
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19 | // #define USE_SNZI |
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20 | |
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21 | #include "bits/defs.hfa" |
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22 | #include "kernel_private.hfa" |
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23 | |
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24 | #define _GNU_SOURCE |
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25 | #include "stdlib.hfa" |
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26 | #include "math.hfa" |
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27 | |
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28 | #include <unistd.h> |
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29 | |
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30 | #include "snzi.hfa" |
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31 | #include "ready_subqueue.hfa" |
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32 | |
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33 | static const size_t cache_line_size = 64; |
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34 | |
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35 | // No overriden function, no environment variable, no define |
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36 | // fall back to a magic number |
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37 | #ifndef __CFA_MAX_PROCESSORS__ |
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38 | #define __CFA_MAX_PROCESSORS__ 1024 |
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39 | #endif |
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40 | |
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41 | #define BIAS 16 |
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42 | |
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43 | // returns the maximum number of processors the RWLock support |
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44 | __attribute__((weak)) unsigned __max_processors() { |
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45 | const char * max_cores_s = getenv("CFA_MAX_PROCESSORS"); |
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46 | if(!max_cores_s) { |
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47 | __cfadbg_print_nolock(ready_queue, "No CFA_MAX_PROCESSORS in ENV\n"); |
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48 | return __CFA_MAX_PROCESSORS__; |
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49 | } |
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50 | |
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51 | char * endptr = 0p; |
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52 | long int max_cores_l = strtol(max_cores_s, &endptr, 10); |
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53 | if(max_cores_l < 1 || max_cores_l > 65535) { |
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54 | __cfadbg_print_nolock(ready_queue, "CFA_MAX_PROCESSORS out of range : %ld\n", max_cores_l); |
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55 | return __CFA_MAX_PROCESSORS__; |
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56 | } |
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57 | if('\0' != *endptr) { |
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58 | __cfadbg_print_nolock(ready_queue, "CFA_MAX_PROCESSORS not a decimal number : %s\n", max_cores_s); |
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59 | return __CFA_MAX_PROCESSORS__; |
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60 | } |
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61 | |
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62 | return max_cores_l; |
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63 | } |
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64 | |
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65 | //======================================================================= |
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66 | // Cluster wide reader-writer lock |
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67 | //======================================================================= |
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68 | void ?{}(__scheduler_RWLock_t & this) { |
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69 | this.max = __max_processors(); |
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70 | this.alloc = 0; |
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71 | this.ready = 0; |
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72 | this.lock = false; |
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73 | this.data = alloc(this.max); |
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74 | |
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75 | /*paranoid*/ verify( 0 == (((uintptr_t)(this.data )) % 64) ); |
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76 | /*paranoid*/ verify( 0 == (((uintptr_t)(this.data + 1)) % 64) ); |
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77 | /*paranoid*/ verify(__atomic_is_lock_free(sizeof(this.alloc), &this.alloc)); |
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78 | /*paranoid*/ verify(__atomic_is_lock_free(sizeof(this.ready), &this.ready)); |
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79 | |
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80 | } |
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81 | void ^?{}(__scheduler_RWLock_t & this) { |
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82 | free(this.data); |
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83 | } |
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84 | |
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85 | void ?{}( __scheduler_lock_id_t & this, __processor_id_t * proc ) { |
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86 | this.handle = proc; |
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87 | this.lock = false; |
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88 | #ifdef __CFA_WITH_VERIFY__ |
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89 | this.owned = false; |
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90 | #endif |
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91 | } |
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92 | |
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93 | //======================================================================= |
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94 | // Lock-Free registering/unregistering of threads |
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95 | unsigned doregister( struct __processor_id_t * proc ) with(*__scheduler_lock) { |
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96 | __cfadbg_print_safe(ready_queue, "Kernel : Registering proc %p for RW-Lock\n", proc); |
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97 | |
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98 | // Step - 1 : check if there is already space in the data |
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99 | uint_fast32_t s = ready; |
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100 | |
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101 | // Check among all the ready |
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102 | for(uint_fast32_t i = 0; i < s; i++) { |
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103 | __processor_id_t * null = 0p; // Re-write every loop since compare thrashes it |
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104 | if( __atomic_load_n(&data[i].handle, (int)__ATOMIC_RELAXED) == null |
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105 | && __atomic_compare_exchange_n( &data[i].handle, &null, proc, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)) { |
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106 | /*paranoid*/ verify(i < ready); |
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107 | /*paranoid*/ verify(0 == (__alignof__(data[i]) % cache_line_size)); |
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108 | /*paranoid*/ verify((((uintptr_t)&data[i]) % cache_line_size) == 0); |
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109 | return i; |
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110 | } |
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111 | } |
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112 | |
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113 | if(max <= alloc) abort("Trying to create more than %ud processors", __scheduler_lock->max); |
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114 | |
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115 | // Step - 2 : F&A to get a new spot in the array. |
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116 | uint_fast32_t n = __atomic_fetch_add(&alloc, 1, __ATOMIC_SEQ_CST); |
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117 | if(max <= n) abort("Trying to create more than %ud processors", __scheduler_lock->max); |
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118 | |
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119 | // Step - 3 : Mark space as used and then publish it. |
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120 | __scheduler_lock_id_t * storage = (__scheduler_lock_id_t *)&data[n]; |
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121 | (*storage){ proc }; |
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122 | while(true) { |
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123 | unsigned copy = n; |
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124 | if( __atomic_load_n(&ready, __ATOMIC_RELAXED) == n |
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125 | && __atomic_compare_exchange_n(&ready, ©, n + 1, true, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)) |
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126 | break; |
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127 | asm volatile("pause"); |
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128 | } |
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129 | |
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130 | __cfadbg_print_safe(ready_queue, "Kernel : Registering proc %p done, id %lu\n", proc, n); |
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131 | |
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132 | // Return new spot. |
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133 | /*paranoid*/ verify(n < ready); |
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134 | /*paranoid*/ verify(__alignof__(data[n]) == (2 * cache_line_size)); |
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135 | /*paranoid*/ verify((((uintptr_t)&data[n]) % cache_line_size) == 0); |
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136 | return n; |
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137 | } |
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138 | |
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139 | void unregister( struct __processor_id_t * proc ) with(*__scheduler_lock) { |
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140 | unsigned id = proc->id; |
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141 | /*paranoid*/ verify(id < ready); |
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142 | /*paranoid*/ verify(proc == __atomic_load_n(&data[id].handle, __ATOMIC_RELAXED)); |
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143 | __atomic_store_n(&data[id].handle, 0p, __ATOMIC_RELEASE); |
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144 | |
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145 | __cfadbg_print_safe(ready_queue, "Kernel : Unregister proc %p\n", proc); |
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146 | } |
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147 | |
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148 | //----------------------------------------------------------------------- |
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149 | // Writer side : acquire when changing the ready queue, e.g. adding more |
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150 | // queues or removing them. |
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151 | uint_fast32_t ready_mutate_lock( void ) with(*__scheduler_lock) { |
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152 | // Step 1 : lock global lock |
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153 | // It is needed to avoid processors that register mid Critical-Section |
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154 | // to simply lock their own lock and enter. |
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155 | __atomic_acquire( &lock ); |
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156 | |
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157 | // Step 2 : lock per-proc lock |
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158 | // Processors that are currently being registered aren't counted |
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159 | // but can't be in read_lock or in the critical section. |
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160 | // All other processors are counted |
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161 | uint_fast32_t s = ready; |
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162 | for(uint_fast32_t i = 0; i < s; i++) { |
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163 | __atomic_acquire( &data[i].lock ); |
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164 | } |
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165 | |
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166 | return s; |
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167 | } |
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168 | |
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169 | void ready_mutate_unlock( uint_fast32_t last_s ) with(*__scheduler_lock) { |
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170 | // Step 1 : release local locks |
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171 | // This must be done while the global lock is held to avoid |
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172 | // threads that where created mid critical section |
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173 | // to race to lock their local locks and have the writer |
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174 | // immidiately unlock them |
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175 | // Alternative solution : return s in write_lock and pass it to write_unlock |
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176 | for(uint_fast32_t i = 0; i < last_s; i++) { |
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177 | verify(data[i].lock); |
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178 | __atomic_store_n(&data[i].lock, (bool)false, __ATOMIC_RELEASE); |
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179 | } |
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180 | |
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181 | // Step 2 : release global lock |
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182 | /*paranoid*/ assert(true == lock); |
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183 | __atomic_store_n(&lock, (bool)false, __ATOMIC_RELEASE); |
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184 | } |
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185 | |
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186 | //======================================================================= |
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187 | // Cforall Reqdy Queue used for scheduling |
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188 | //======================================================================= |
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189 | void ?{}(__ready_queue_t & this) with (this) { |
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190 | lanes.data = 0p; |
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191 | lanes.count = 0; |
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192 | } |
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193 | |
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194 | void ^?{}(__ready_queue_t & this) with (this) { |
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195 | verify( 1 == lanes.count ); |
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196 | #ifdef USE_SNZI |
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197 | verify( !query( snzi ) ); |
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198 | #endif |
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199 | free(lanes.data); |
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200 | } |
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201 | |
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202 | //----------------------------------------------------------------------- |
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203 | __attribute__((hot)) bool query(struct cluster * cltr) { |
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204 | #ifdef USE_SNZI |
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205 | return query(cltr->ready_queue.snzi); |
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206 | #endif |
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207 | return true; |
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208 | } |
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209 | |
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210 | //----------------------------------------------------------------------- |
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211 | __attribute__((hot)) bool push(struct cluster * cltr, struct $thread * thrd) with (cltr->ready_queue) { |
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212 | __cfadbg_print_safe(ready_queue, "Kernel : Pushing %p on cluster %p\n", thrd, cltr); |
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213 | |
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214 | // write timestamp |
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215 | thrd->link.ts = rdtscl(); |
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216 | |
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217 | #if defined(BIAS) && !defined(__CFA_NO_STATISTICS__) |
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218 | bool local = false; |
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219 | int preferred = |
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220 | //* |
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221 | kernelTLS.this_processor ? kernelTLS.this_processor->id * 4 : -1; |
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222 | /*/ |
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223 | thrd->link.preferred * 4; |
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224 | //*/ |
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225 | |
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226 | |
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227 | #endif |
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228 | |
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229 | // Try to pick a lane and lock it |
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230 | unsigned i; |
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231 | do { |
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232 | // Pick the index of a lane |
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233 | #if defined(BIAS) |
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234 | unsigned r = __tls_rand(); |
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235 | unsigned rlow = r % BIAS; |
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236 | unsigned rhigh = r / BIAS; |
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237 | if((0 != rlow) && preferred >= 0) { |
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238 | // (BIAS - 1) out of BIAS chances |
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239 | // Use perferred queues |
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240 | i = preferred + (rhigh % 4); |
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241 | |
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242 | #if !defined(__CFA_NO_STATISTICS__) |
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243 | local = true; |
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244 | __tls_stats()->ready.pick.push.local++; |
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245 | #endif |
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246 | } |
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247 | else { |
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248 | // 1 out of BIAS chances |
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249 | // Use all queues |
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250 | i = rhigh; |
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251 | local = false; |
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252 | } |
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253 | #else |
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254 | i = __tls_rand(); |
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255 | #endif |
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256 | |
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257 | i %= __atomic_load_n( &lanes.count, __ATOMIC_RELAXED ); |
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258 | |
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259 | #if !defined(__CFA_NO_STATISTICS__) |
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260 | __tls_stats()->ready.pick.push.attempt++; |
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261 | #endif |
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262 | |
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263 | // If we can't lock it retry |
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264 | } while( !__atomic_try_acquire( &lanes.data[i].lock ) ); |
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265 | |
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266 | bool first = false; |
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267 | |
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268 | // Actually push it |
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269 | bool lane_first = push(lanes.data[i], thrd); |
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270 | |
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271 | #ifdef USE_SNZI |
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272 | // If this lane used to be empty we need to do more |
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273 | if(lane_first) { |
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274 | // Check if the entire queue used to be empty |
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275 | first = !query(snzi); |
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276 | |
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277 | // Update the snzi |
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278 | arrive( snzi, i ); |
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279 | } |
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280 | #endif |
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281 | |
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282 | // Unlock and return |
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283 | __atomic_unlock( &lanes.data[i].lock ); |
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284 | |
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285 | __cfadbg_print_safe(ready_queue, "Kernel : Pushed %p on cluster %p (idx: %u, mask %llu, first %d)\n", thrd, cltr, i, used.mask[0], lane_first); |
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286 | |
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287 | // Update statistics |
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288 | #if !defined(__CFA_NO_STATISTICS__) |
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289 | #if defined(BIAS) |
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290 | if( local ) __tls_stats()->ready.pick.push.lsuccess++; |
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291 | #endif |
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292 | __tls_stats()->ready.pick.push.success++; |
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293 | #endif |
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294 | |
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295 | // return whether or not the list was empty before this push |
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296 | return first; |
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297 | } |
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298 | |
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299 | static struct $thread * try_pop(struct cluster * cltr, unsigned i, unsigned j); |
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300 | static struct $thread * try_pop(struct cluster * cltr, unsigned i); |
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301 | |
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302 | // Pop from the ready queue from a given cluster |
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303 | __attribute__((hot)) $thread * pop(struct cluster * cltr) with (cltr->ready_queue) { |
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304 | /* paranoid */ verify( lanes.count > 0 ); |
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305 | unsigned count = __atomic_load_n( &lanes.count, __ATOMIC_RELAXED ); |
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306 | #if defined(BIAS) |
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307 | // Don't bother trying locally too much |
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308 | int local_tries = 8; |
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309 | #endif |
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310 | |
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311 | // As long as the list is not empty, try finding a lane that isn't empty and pop from it |
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312 | #ifdef USE_SNZI |
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313 | while( query(snzi) ) { |
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314 | #else |
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315 | for(25) { |
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316 | #endif |
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317 | // Pick two lists at random |
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318 | unsigned i,j; |
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319 | #if defined(BIAS) |
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320 | #if !defined(__CFA_NO_STATISTICS__) |
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321 | bool local = false; |
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322 | #endif |
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323 | uint64_t r = __tls_rand(); |
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324 | unsigned rlow = r % BIAS; |
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325 | uint64_t rhigh = r / BIAS; |
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326 | if(local_tries && 0 != rlow) { |
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327 | // (BIAS - 1) out of BIAS chances |
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328 | // Use perferred queues |
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329 | unsigned pid = kernelTLS.this_processor->id * 4; |
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330 | i = pid + (rhigh % 4); |
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331 | j = pid + ((rhigh >> 32ull) % 4); |
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332 | |
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333 | // count the tries |
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334 | local_tries--; |
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335 | |
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336 | #if !defined(__CFA_NO_STATISTICS__) |
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337 | local = true; |
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338 | __tls_stats()->ready.pick.pop.local++; |
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339 | #endif |
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340 | } |
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341 | else { |
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342 | // 1 out of BIAS chances |
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343 | // Use all queues |
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344 | i = rhigh; |
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345 | j = rhigh >> 32ull; |
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346 | } |
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347 | #else |
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348 | i = __tls_rand(); |
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349 | j = __tls_rand(); |
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350 | #endif |
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351 | |
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352 | i %= count; |
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353 | j %= count; |
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354 | |
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355 | // try popping from the 2 picked lists |
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356 | struct $thread * thrd = try_pop(cltr, i, j); |
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357 | if(thrd) { |
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358 | #if defined(BIAS) && !defined(__CFA_NO_STATISTICS__) |
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359 | if( local ) __tls_stats()->ready.pick.pop.lsuccess++; |
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360 | #endif |
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361 | return thrd; |
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362 | } |
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363 | } |
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364 | |
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365 | // All lanes where empty return 0p |
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366 | return 0p; |
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367 | } |
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368 | |
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369 | __attribute__((hot)) struct $thread * pop_slow(struct cluster * cltr) with (cltr->ready_queue) { |
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370 | /* paranoid */ verify( lanes.count > 0 ); |
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371 | unsigned count = __atomic_load_n( &lanes.count, __ATOMIC_RELAXED ); |
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372 | unsigned offset = __tls_rand(); |
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373 | for(i; count) { |
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374 | unsigned idx = (offset + i) % count; |
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375 | struct $thread * thrd = try_pop(cltr, idx); |
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376 | if(thrd) { |
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377 | return thrd; |
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378 | } |
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379 | } |
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380 | |
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381 | // All lanes where empty return 0p |
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382 | return 0p; |
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383 | } |
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384 | |
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385 | |
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386 | //----------------------------------------------------------------------- |
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387 | // Given 2 indexes, pick the list with the oldest push an try to pop from it |
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388 | static inline struct $thread * try_pop(struct cluster * cltr, unsigned i, unsigned j) with (cltr->ready_queue) { |
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389 | #if !defined(__CFA_NO_STATISTICS__) |
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390 | __tls_stats()->ready.pick.pop.attempt++; |
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391 | #endif |
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392 | |
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393 | // Pick the bet list |
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394 | int w = i; |
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395 | if( __builtin_expect(!is_empty(lanes.data[j]), true) ) { |
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396 | w = (ts(lanes.data[i]) < ts(lanes.data[j])) ? i : j; |
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397 | } |
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398 | |
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399 | return try_pop(cltr, w); |
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400 | } |
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401 | |
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402 | static inline struct $thread * try_pop(struct cluster * cltr, unsigned w) with (cltr->ready_queue) { |
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403 | // Get relevant elements locally |
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404 | __intrusive_lane_t & lane = lanes.data[w]; |
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405 | |
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406 | // If list looks empty retry |
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407 | if( is_empty(lane) ) return 0p; |
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408 | |
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409 | // If we can't get the lock retry |
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410 | if( !__atomic_try_acquire(&lane.lock) ) return 0p; |
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411 | |
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412 | |
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413 | // If list is empty, unlock and retry |
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414 | if( is_empty(lane) ) { |
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415 | __atomic_unlock(&lane.lock); |
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416 | return 0p; |
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417 | } |
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418 | |
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419 | // Actually pop the list |
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420 | struct $thread * thrd; |
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421 | bool emptied; |
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422 | [thrd, emptied] = pop(lane); |
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423 | |
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424 | /* paranoid */ verify(thrd); |
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425 | /* paranoid */ verify(lane.lock); |
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426 | |
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427 | #ifdef USE_SNZI |
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428 | // If this was the last element in the lane |
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429 | if(emptied) { |
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430 | depart( snzi, w ); |
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431 | } |
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432 | #endif |
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433 | |
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434 | // Unlock and return |
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435 | __atomic_unlock(&lane.lock); |
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436 | |
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437 | // Update statistics |
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438 | #if !defined(__CFA_NO_STATISTICS__) |
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439 | __tls_stats()->ready.pick.pop.success++; |
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440 | #endif |
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441 | |
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442 | // Update the thread bias |
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443 | thrd->link.preferred = w / 4; |
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444 | |
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445 | // return the popped thread |
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446 | return thrd; |
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447 | } |
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448 | //----------------------------------------------------------------------- |
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449 | |
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450 | bool remove_head(struct cluster * cltr, struct $thread * thrd) with (cltr->ready_queue) { |
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451 | for(i; lanes.count) { |
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452 | __intrusive_lane_t & lane = lanes.data[i]; |
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453 | |
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454 | bool removed = false; |
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455 | |
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456 | __atomic_acquire(&lane.lock); |
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457 | if(head(lane)->link.next == thrd) { |
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458 | $thread * pthrd; |
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459 | bool emptied; |
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460 | [pthrd, emptied] = pop(lane); |
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461 | |
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462 | /* paranoid */ verify( pthrd == thrd ); |
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463 | |
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464 | removed = true; |
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465 | #ifdef USE_SNZI |
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466 | if(emptied) { |
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467 | depart( snzi, i ); |
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468 | } |
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469 | #endif |
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470 | } |
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471 | __atomic_unlock(&lane.lock); |
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472 | |
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473 | if( removed ) return true; |
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474 | } |
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475 | return false; |
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476 | } |
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477 | |
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478 | //----------------------------------------------------------------------- |
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479 | |
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480 | static void check( __ready_queue_t & q ) with (q) { |
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481 | #if defined(__CFA_WITH_VERIFY__) |
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482 | { |
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483 | for( idx ; lanes.count ) { |
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484 | __intrusive_lane_t & sl = lanes.data[idx]; |
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485 | assert(!lanes.data[idx].lock); |
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486 | |
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487 | assert(head(sl)->link.prev == 0p ); |
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488 | assert(head(sl)->link.next->link.prev == head(sl) ); |
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489 | assert(tail(sl)->link.next == 0p ); |
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490 | assert(tail(sl)->link.prev->link.next == tail(sl) ); |
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491 | |
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492 | if(sl.before.link.ts == 0l) { |
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493 | assert(tail(sl)->link.prev == head(sl)); |
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494 | assert(head(sl)->link.next == tail(sl)); |
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495 | } else { |
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496 | assert(tail(sl)->link.prev != head(sl)); |
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497 | assert(head(sl)->link.next != tail(sl)); |
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498 | } |
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499 | } |
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500 | } |
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501 | #endif |
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502 | } |
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503 | |
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504 | // Call this function of the intrusive list was moved using memcpy |
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505 | // fixes the list so that the pointers back to anchors aren't left dangling |
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506 | static inline void fix(__intrusive_lane_t & ll) { |
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507 | // if the list is not empty then follow he pointer and fix its reverse |
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508 | if(!is_empty(ll)) { |
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509 | head(ll)->link.next->link.prev = head(ll); |
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510 | tail(ll)->link.prev->link.next = tail(ll); |
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511 | } |
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512 | // Otherwise just reset the list |
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513 | else { |
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514 | verify(tail(ll)->link.next == 0p); |
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515 | tail(ll)->link.prev = head(ll); |
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516 | head(ll)->link.next = tail(ll); |
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517 | verify(head(ll)->link.prev == 0p); |
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518 | } |
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519 | } |
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520 | |
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521 | // Grow the ready queue |
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522 | void ready_queue_grow (struct cluster * cltr, int target) { |
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523 | /* paranoid */ verify( ready_mutate_islocked() ); |
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524 | __cfadbg_print_safe(ready_queue, "Kernel : Growing ready queue\n"); |
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525 | |
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526 | // Make sure that everything is consistent |
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527 | /* paranoid */ check( cltr->ready_queue ); |
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528 | |
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529 | // grow the ready queue |
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530 | with( cltr->ready_queue ) { |
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531 | #ifdef USE_SNZI |
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532 | ^(snzi){}; |
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533 | #endif |
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534 | |
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535 | // Find new count |
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536 | // Make sure we always have atleast 1 list |
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537 | size_t ncount = target >= 2 ? target * 4: 1; |
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538 | |
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539 | // Allocate new array (uses realloc and memcpies the data) |
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540 | lanes.data = alloc(lanes.data, ncount); |
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541 | |
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542 | // Fix the moved data |
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543 | for( idx; (size_t)lanes.count ) { |
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544 | fix(lanes.data[idx]); |
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545 | } |
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546 | |
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547 | // Construct new data |
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548 | for( idx; (size_t)lanes.count ~ ncount) { |
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549 | (lanes.data[idx]){}; |
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550 | } |
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551 | |
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552 | // Update original |
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553 | lanes.count = ncount; |
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554 | |
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555 | #ifdef USE_SNZI |
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556 | // Re-create the snzi |
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557 | snzi{ log2( lanes.count / 8 ) }; |
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558 | for( idx; (size_t)lanes.count ) { |
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559 | if( !is_empty(lanes.data[idx]) ) { |
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560 | arrive(snzi, idx); |
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561 | } |
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562 | } |
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563 | #endif |
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564 | } |
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565 | |
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566 | // Make sure that everything is consistent |
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567 | /* paranoid */ check( cltr->ready_queue ); |
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568 | |
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569 | __cfadbg_print_safe(ready_queue, "Kernel : Growing ready queue done\n"); |
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570 | |
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571 | /* paranoid */ verify( ready_mutate_islocked() ); |
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572 | } |
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573 | |
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574 | // Shrink the ready queue |
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575 | void ready_queue_shrink(struct cluster * cltr, int target) { |
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576 | /* paranoid */ verify( ready_mutate_islocked() ); |
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577 | __cfadbg_print_safe(ready_queue, "Kernel : Shrinking ready queue\n"); |
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578 | |
---|
579 | // Make sure that everything is consistent |
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580 | /* paranoid */ check( cltr->ready_queue ); |
---|
581 | |
---|
582 | with( cltr->ready_queue ) { |
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583 | #ifdef USE_SNZI |
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584 | ^(snzi){}; |
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585 | #endif |
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586 | |
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587 | // Remember old count |
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588 | size_t ocount = lanes.count; |
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589 | |
---|
590 | // Find new count |
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591 | // Make sure we always have atleast 1 list |
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592 | lanes.count = target >= 2 ? target * 4: 1; |
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593 | /* paranoid */ verify( ocount >= lanes.count ); |
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594 | /* paranoid */ verify( lanes.count == target * 4 || target < 2 ); |
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595 | |
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596 | // for printing count the number of displaced threads |
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597 | #if defined(__CFA_DEBUG_PRINT__) || defined(__CFA_DEBUG_PRINT_READY_QUEUE__) |
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598 | __attribute__((unused)) size_t displaced = 0; |
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599 | #endif |
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600 | |
---|
601 | // redistribute old data |
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602 | for( idx; (size_t)lanes.count ~ ocount) { |
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603 | // Lock is not strictly needed but makes checking invariants much easier |
---|
604 | __attribute__((unused)) bool locked = __atomic_try_acquire(&lanes.data[idx].lock); |
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605 | verify(locked); |
---|
606 | |
---|
607 | // As long as we can pop from this lane to push the threads somewhere else in the queue |
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608 | while(!is_empty(lanes.data[idx])) { |
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609 | struct $thread * thrd; |
---|
610 | __attribute__((unused)) bool _; |
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611 | [thrd, _] = pop(lanes.data[idx]); |
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612 | |
---|
613 | push(cltr, thrd); |
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614 | |
---|
615 | // for printing count the number of displaced threads |
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616 | #if defined(__CFA_DEBUG_PRINT__) || defined(__CFA_DEBUG_PRINT_READY_QUEUE__) |
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617 | displaced++; |
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618 | #endif |
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619 | } |
---|
620 | |
---|
621 | // Unlock the lane |
---|
622 | __atomic_unlock(&lanes.data[idx].lock); |
---|
623 | |
---|
624 | // TODO print the queue statistics here |
---|
625 | |
---|
626 | ^(lanes.data[idx]){}; |
---|
627 | } |
---|
628 | |
---|
629 | __cfadbg_print_safe(ready_queue, "Kernel : Shrinking ready queue displaced %zu threads\n", displaced); |
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630 | |
---|
631 | // Allocate new array (uses realloc and memcpies the data) |
---|
632 | lanes.data = alloc(lanes.data, lanes.count); |
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633 | |
---|
634 | // Fix the moved data |
---|
635 | for( idx; (size_t)lanes.count ) { |
---|
636 | fix(lanes.data[idx]); |
---|
637 | } |
---|
638 | |
---|
639 | #ifdef USE_SNZI |
---|
640 | // Re-create the snzi |
---|
641 | snzi{ log2( lanes.count / 8 ) }; |
---|
642 | for( idx; (size_t)lanes.count ) { |
---|
643 | if( !is_empty(lanes.data[idx]) ) { |
---|
644 | arrive(snzi, idx); |
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645 | } |
---|
646 | } |
---|
647 | #endif |
---|
648 | } |
---|
649 | |
---|
650 | // Make sure that everything is consistent |
---|
651 | /* paranoid */ check( cltr->ready_queue ); |
---|
652 | |
---|
653 | __cfadbg_print_safe(ready_queue, "Kernel : Shrinking ready queue done\n"); |
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654 | /* paranoid */ verify( ready_mutate_islocked() ); |
---|
655 | } |
---|