[8118303] | 1 | // |
---|
| 2 | // Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo |
---|
| 3 | // |
---|
| 4 | // The contents of this file are covered under the licence agreement in the |
---|
| 5 | // file "LICENCE" distributed with Cforall. |
---|
| 6 | // |
---|
| 7 | // kernel.c -- |
---|
| 8 | // |
---|
| 9 | // Author : Thierry Delisle |
---|
[75f3522] | 10 | // Created On : Tue Jan 17 12:27:26 2017 |
---|
[6b0b624] | 11 | // Last Modified By : Peter A. Buhr |
---|
| 12 | // Last Modified On : Fri Jul 21 22:33:18 2017 |
---|
| 13 | // Update Count : 2 |
---|
[8118303] | 14 | // |
---|
| 15 | |
---|
[2ac095d] | 16 | #include "libhdr.h" |
---|
[8118303] | 17 | |
---|
| 18 | //C Includes |
---|
[c84e80a] | 19 | #include <stddef.h> |
---|
[eb2e723] | 20 | extern "C" { |
---|
[9d944b2] | 21 | #include <stdio.h> |
---|
[8fcbb4c] | 22 | #include <fenv.h> |
---|
[eb2e723] | 23 | #include <sys/resource.h> |
---|
[9d944b2] | 24 | #include <signal.h> |
---|
| 25 | #include <unistd.h> |
---|
[eb2e723] | 26 | } |
---|
[8118303] | 27 | |
---|
| 28 | //CFA Includes |
---|
[2ac095d] | 29 | #include "kernel_private.h" |
---|
[c81ebf9] | 30 | #include "preemption.h" |
---|
[2ac095d] | 31 | #include "startup.h" |
---|
[8118303] | 32 | |
---|
| 33 | //Private includes |
---|
| 34 | #define __CFA_INVOKE_PRIVATE__ |
---|
| 35 | #include "invoke.h" |
---|
| 36 | |
---|
[2ac095d] | 37 | //Start and stop routine for the kernel, declared first to make sure they run first |
---|
| 38 | void kernel_startup(void) __attribute__(( constructor( STARTUP_PRIORITY_KERNEL ) )); |
---|
| 39 | void kernel_shutdown(void) __attribute__(( destructor ( STARTUP_PRIORITY_KERNEL ) )); |
---|
| 40 | |
---|
[8def349] | 41 | //----------------------------------------------------------------------------- |
---|
| 42 | // Kernel storage |
---|
[969b3fe] | 43 | KERNEL_STORAGE(cluster, mainCluster); |
---|
| 44 | KERNEL_STORAGE(processor, mainProcessor); |
---|
| 45 | KERNEL_STORAGE(processorCtx_t, mainProcessorCtx); |
---|
| 46 | KERNEL_STORAGE(thread_desc, mainThread); |
---|
[f2b12406] | 47 | KERNEL_STORAGE(machine_context_t, mainThreadCtx); |
---|
[8def349] | 48 | |
---|
[969b3fe] | 49 | cluster * mainCluster; |
---|
| 50 | processor * mainProcessor; |
---|
[348006f] | 51 | thread_desc * mainThread; |
---|
[eb2e723] | 52 | |
---|
[bd98b58] | 53 | //----------------------------------------------------------------------------- |
---|
| 54 | // Global state |
---|
| 55 | |
---|
[9cc0472] | 56 | thread_local coroutine_desc * volatile this_coroutine; |
---|
| 57 | thread_local thread_desc * volatile this_thread; |
---|
| 58 | thread_local processor * volatile this_processor; |
---|
[969b3fe] | 59 | |
---|
[d6ff3ff] | 60 | volatile thread_local bool preemption_in_progress = 0; |
---|
[1c273d0] | 61 | volatile thread_local unsigned short disable_preempt_count = 1; |
---|
[c84e80a] | 62 | |
---|
| 63 | //----------------------------------------------------------------------------- |
---|
[8def349] | 64 | // Main thread construction |
---|
| 65 | struct current_stack_info_t { |
---|
[1c273d0] | 66 | machine_context_t ctx; |
---|
[8def349] | 67 | unsigned int size; // size of stack |
---|
| 68 | void *base; // base of stack |
---|
| 69 | void *storage; // pointer to stack |
---|
| 70 | void *limit; // stack grows towards stack limit |
---|
| 71 | void *context; // address of cfa_context_t |
---|
| 72 | void *top; // address of top of storage |
---|
[c84e80a] | 73 | }; |
---|
| 74 | |
---|
[242a902] | 75 | void ?{}( current_stack_info_t & this ) { |
---|
| 76 | CtxGet( this.ctx ); |
---|
| 77 | this.base = this.ctx.FP; |
---|
| 78 | this.storage = this.ctx.SP; |
---|
[8def349] | 79 | |
---|
| 80 | rlimit r; |
---|
[132fad4] | 81 | getrlimit( RLIMIT_STACK, &r); |
---|
[242a902] | 82 | this.size = r.rlim_cur; |
---|
[8def349] | 83 | |
---|
[242a902] | 84 | this.limit = (void *)(((intptr_t)this.base) - this.size); |
---|
[9236060] | 85 | this.context = &storage_mainThreadCtx; |
---|
[242a902] | 86 | this.top = this.base; |
---|
[8def349] | 87 | } |
---|
| 88 | |
---|
[242a902] | 89 | void ?{}( coStack_t & this, current_stack_info_t * info) { |
---|
| 90 | this.size = info->size; |
---|
| 91 | this.storage = info->storage; |
---|
| 92 | this.limit = info->limit; |
---|
| 93 | this.base = info->base; |
---|
| 94 | this.context = info->context; |
---|
| 95 | this.top = info->top; |
---|
| 96 | this.userStack = true; |
---|
[8def349] | 97 | } |
---|
| 98 | |
---|
[242a902] | 99 | void ?{}( coroutine_desc & this, current_stack_info_t * info) { |
---|
| 100 | (this.stack){ info }; |
---|
| 101 | this.name = "Main Thread"; |
---|
| 102 | this.errno_ = 0; |
---|
| 103 | this.state = Start; |
---|
[8def349] | 104 | } |
---|
| 105 | |
---|
[242a902] | 106 | void ?{}( thread_desc & this, current_stack_info_t * info) { |
---|
| 107 | (this.cor){ info }; |
---|
[8def349] | 108 | } |
---|
[c84e80a] | 109 | |
---|
[8def349] | 110 | //----------------------------------------------------------------------------- |
---|
| 111 | // Processor coroutine |
---|
[242a902] | 112 | void ?{}(processorCtx_t & this, processor * proc) { |
---|
| 113 | (this.__cor){ "Processor" }; |
---|
| 114 | this.proc = proc; |
---|
| 115 | proc->runner = &this; |
---|
[8def349] | 116 | } |
---|
| 117 | |
---|
[242a902] | 118 | void ?{}(processorCtx_t & this, processor * proc, current_stack_info_t * info) { |
---|
| 119 | (this.__cor){ info }; |
---|
| 120 | this.proc = proc; |
---|
| 121 | proc->runner = &this; |
---|
[8def349] | 122 | } |
---|
| 123 | |
---|
[242a902] | 124 | void ?{}(processor & this) { |
---|
[969b3fe] | 125 | this{ mainCluster }; |
---|
[8def349] | 126 | } |
---|
| 127 | |
---|
[242a902] | 128 | void ?{}(processor & this, cluster * cltr) { |
---|
| 129 | this.cltr = cltr; |
---|
| 130 | (this.terminated){ 0 }; |
---|
[9236060] | 131 | this.do_terminate = false; |
---|
[242a902] | 132 | this.preemption_alarm = NULL; |
---|
| 133 | this.pending_preemption = false; |
---|
[8def349] | 134 | |
---|
[242a902] | 135 | start( &this ); |
---|
[c84e80a] | 136 | } |
---|
| 137 | |
---|
[83a071f9] | 138 | void ?{}(processor & this, cluster * cltr, processorCtx_t & runner) { |
---|
[242a902] | 139 | this.cltr = cltr; |
---|
| 140 | (this.terminated){ 0 }; |
---|
[9236060] | 141 | this.do_terminate = false; |
---|
[242a902] | 142 | this.preemption_alarm = NULL; |
---|
| 143 | this.pending_preemption = false; |
---|
| 144 | this.kernel_thread = pthread_self(); |
---|
[8def349] | 145 | |
---|
[83a071f9] | 146 | this.runner = &runner; |
---|
[9236060] | 147 | LIB_DEBUG_PRINT_SAFE("Kernel : constructing main processor context %p\n", &runner); |
---|
[83a071f9] | 148 | runner{ &this }; |
---|
[8def349] | 149 | } |
---|
| 150 | |
---|
[242a902] | 151 | void ^?{}(processor & this) { |
---|
[9236060] | 152 | if( ! this.do_terminate ) { |
---|
[242a902] | 153 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p signaling termination\n", &this); |
---|
[9236060] | 154 | this.do_terminate = true; |
---|
[53a8e68] | 155 | P( &this.terminated ); |
---|
[242a902] | 156 | pthread_join( this.kernel_thread, NULL ); |
---|
[8def349] | 157 | } |
---|
| 158 | } |
---|
| 159 | |
---|
[242a902] | 160 | void ?{}(cluster & this) { |
---|
| 161 | ( this.ready_queue ){}; |
---|
[9236060] | 162 | ( this.ready_queue_lock ){}; |
---|
[e60e0dc] | 163 | |
---|
[9236060] | 164 | this.preemption = default_preemption(); |
---|
[8def349] | 165 | } |
---|
| 166 | |
---|
[242a902] | 167 | void ^?{}(cluster & this) { |
---|
[1c273d0] | 168 | |
---|
[c84e80a] | 169 | } |
---|
| 170 | |
---|
[75f3522] | 171 | //============================================================================================= |
---|
| 172 | // Kernel Scheduling logic |
---|
| 173 | //============================================================================================= |
---|
[8fcbb4c] | 174 | //Main of the processor contexts |
---|
[83a071f9] | 175 | void main(processorCtx_t & runner) { |
---|
| 176 | processor * this = runner.proc; |
---|
[c81ebf9] | 177 | |
---|
[9d944b2] | 178 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p starting\n", this); |
---|
[8118303] | 179 | |
---|
[75f3522] | 180 | { |
---|
[c81ebf9] | 181 | // Setup preemption data |
---|
| 182 | preemption_scope scope = { this }; |
---|
| 183 | |
---|
| 184 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p started\n", this); |
---|
[8118303] | 185 | |
---|
[c81ebf9] | 186 | thread_desc * readyThread = NULL; |
---|
[e60e0dc] | 187 | for( unsigned int spin_count = 0; ! this->do_terminate; spin_count++ ) |
---|
[75f3522] | 188 | { |
---|
[c81ebf9] | 189 | readyThread = nextThread( this->cltr ); |
---|
[75f3522] | 190 | |
---|
[c81ebf9] | 191 | if(readyThread) |
---|
| 192 | { |
---|
[0b33412] | 193 | verify( disable_preempt_count > 0 ); |
---|
[4e6fb8e] | 194 | |
---|
[c81ebf9] | 195 | runThread(this, readyThread); |
---|
[75f3522] | 196 | |
---|
[0b33412] | 197 | verify( disable_preempt_count > 0 ); |
---|
[4e6fb8e] | 198 | |
---|
[c81ebf9] | 199 | //Some actions need to be taken from the kernel |
---|
| 200 | finishRunning(this); |
---|
| 201 | |
---|
| 202 | spin_count = 0; |
---|
| 203 | } |
---|
| 204 | else |
---|
| 205 | { |
---|
| 206 | spin(this, &spin_count); |
---|
| 207 | } |
---|
| 208 | } |
---|
| 209 | |
---|
| 210 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p stopping\n", this); |
---|
[c84e80a] | 211 | } |
---|
[8118303] | 212 | |
---|
[bdeba0b] | 213 | V( &this->terminated ); |
---|
| 214 | |
---|
[9d944b2] | 215 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p terminated\n", this); |
---|
[c84e80a] | 216 | } |
---|
| 217 | |
---|
[1c273d0] | 218 | // runThread runs a thread by context switching |
---|
| 219 | // from the processor coroutine to the target thread |
---|
[348006f] | 220 | void runThread(processor * this, thread_desc * dst) { |
---|
[83a071f9] | 221 | coroutine_desc * proc_cor = get_coroutine(*this->runner); |
---|
[c3acb841] | 222 | coroutine_desc * thrd_cor = get_coroutine(dst); |
---|
[1c273d0] | 223 | |
---|
[75f3522] | 224 | //Reset the terminating actions here |
---|
[db6f06a] | 225 | this->finish.action_code = No_Action; |
---|
[8fcbb4c] | 226 | |
---|
[75f3522] | 227 | //Update global state |
---|
[1c273d0] | 228 | this_thread = dst; |
---|
[75f3522] | 229 | |
---|
| 230 | // Context Switch to the thread |
---|
| 231 | ThreadCtxSwitch(proc_cor, thrd_cor); |
---|
| 232 | // when ThreadCtxSwitch returns we are back in the processor coroutine |
---|
| 233 | } |
---|
| 234 | |
---|
[1c273d0] | 235 | // Once a thread has finished running, some of |
---|
[75f3522] | 236 | // its final actions must be executed from the kernel |
---|
[db6f06a] | 237 | void finishRunning(processor * this) { |
---|
| 238 | if( this->finish.action_code == Release ) { |
---|
| 239 | unlock( this->finish.lock ); |
---|
| 240 | } |
---|
| 241 | else if( this->finish.action_code == Schedule ) { |
---|
| 242 | ScheduleThread( this->finish.thrd ); |
---|
| 243 | } |
---|
| 244 | else if( this->finish.action_code == Release_Schedule ) { |
---|
[1c273d0] | 245 | unlock( this->finish.lock ); |
---|
[db6f06a] | 246 | ScheduleThread( this->finish.thrd ); |
---|
| 247 | } |
---|
[0c78741] | 248 | else if( this->finish.action_code == Release_Multi ) { |
---|
| 249 | for(int i = 0; i < this->finish.lock_count; i++) { |
---|
| 250 | unlock( this->finish.locks[i] ); |
---|
| 251 | } |
---|
| 252 | } |
---|
| 253 | else if( this->finish.action_code == Release_Multi_Schedule ) { |
---|
| 254 | for(int i = 0; i < this->finish.lock_count; i++) { |
---|
| 255 | unlock( this->finish.locks[i] ); |
---|
| 256 | } |
---|
| 257 | for(int i = 0; i < this->finish.thrd_count; i++) { |
---|
| 258 | ScheduleThread( this->finish.thrds[i] ); |
---|
| 259 | } |
---|
| 260 | } |
---|
[db6f06a] | 261 | else { |
---|
| 262 | assert(this->finish.action_code == No_Action); |
---|
[8fcbb4c] | 263 | } |
---|
[c84e80a] | 264 | } |
---|
| 265 | |
---|
[0c92c9f] | 266 | // Handles spinning logic |
---|
| 267 | // TODO : find some strategy to put cores to sleep after some time |
---|
[c84e80a] | 268 | void spin(processor * this, unsigned int * spin_count) { |
---|
| 269 | (*spin_count)++; |
---|
| 270 | } |
---|
| 271 | |
---|
[0c92c9f] | 272 | // Context invoker for processors |
---|
| 273 | // This is the entry point for processors (kernel threads) |
---|
| 274 | // It effectively constructs a coroutine by stealing the pthread stack |
---|
[8def349] | 275 | void * CtxInvokeProcessor(void * arg) { |
---|
| 276 | processor * proc = (processor *) arg; |
---|
| 277 | this_processor = proc; |
---|
[1c273d0] | 278 | this_coroutine = NULL; |
---|
| 279 | this_thread = NULL; |
---|
[4e6fb8e] | 280 | disable_preempt_count = 1; |
---|
[8def349] | 281 | // SKULLDUGGERY: We want to create a context for the processor coroutine |
---|
| 282 | // which is needed for the 2-step context switch. However, there is no reason |
---|
[1c273d0] | 283 | // to waste the perfectly valid stack create by pthread. |
---|
[8def349] | 284 | current_stack_info_t info; |
---|
| 285 | machine_context_t ctx; |
---|
| 286 | info.context = &ctx; |
---|
| 287 | processorCtx_t proc_cor_storage = { proc, &info }; |
---|
| 288 | |
---|
[9d944b2] | 289 | LIB_DEBUG_PRINT_SAFE("Coroutine : created stack %p\n", proc_cor_storage.__cor.stack.base); |
---|
[8fcbb4c] | 290 | |
---|
[0c92c9f] | 291 | //Set global state |
---|
[1c273d0] | 292 | this_coroutine = &proc->runner->__cor; |
---|
| 293 | this_thread = NULL; |
---|
[8def349] | 294 | |
---|
| 295 | //We now have a proper context from which to schedule threads |
---|
[9d944b2] | 296 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p created (%p, %p)\n", proc, proc->runner, &ctx); |
---|
[8def349] | 297 | |
---|
[1c273d0] | 298 | // SKULLDUGGERY: Since the coroutine doesn't have its own stack, we can't |
---|
| 299 | // resume it to start it like it normally would, it will just context switch |
---|
| 300 | // back to here. Instead directly call the main since we already are on the |
---|
[8def349] | 301 | // appropriate stack. |
---|
[17af7d1] | 302 | proc_cor_storage.__cor.state = Active; |
---|
[83a071f9] | 303 | main( proc_cor_storage ); |
---|
[4aa2fb2] | 304 | proc_cor_storage.__cor.state = Halted; |
---|
[8def349] | 305 | |
---|
[0c92c9f] | 306 | // Main routine of the core returned, the core is now fully terminated |
---|
[1c273d0] | 307 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p main ended (%p)\n", proc, proc->runner); |
---|
[8def349] | 308 | |
---|
| 309 | return NULL; |
---|
[c84e80a] | 310 | } |
---|
| 311 | |
---|
[8def349] | 312 | void start(processor * this) { |
---|
[9d944b2] | 313 | LIB_DEBUG_PRINT_SAFE("Kernel : Starting core %p\n", this); |
---|
[82ff5845] | 314 | |
---|
[8fcbb4c] | 315 | pthread_create( &this->kernel_thread, NULL, CtxInvokeProcessor, (void*)this ); |
---|
[eb2e723] | 316 | |
---|
[1c273d0] | 317 | LIB_DEBUG_PRINT_SAFE("Kernel : core %p started\n", this); |
---|
[eb2e723] | 318 | } |
---|
| 319 | |
---|
[8def349] | 320 | //----------------------------------------------------------------------------- |
---|
| 321 | // Scheduler routines |
---|
[348006f] | 322 | void ScheduleThread( thread_desc * thrd ) { |
---|
[1c273d0] | 323 | // if( !thrd ) return; |
---|
| 324 | assert( thrd ); |
---|
| 325 | assert( thrd->cor.state != Halted ); |
---|
| 326 | |
---|
| 327 | verify( disable_preempt_count > 0 ); |
---|
[690f13c] | 328 | |
---|
[4aa2fb2] | 329 | verifyf( thrd->next == NULL, "Expected null got %p", thrd->next ); |
---|
[1c273d0] | 330 | |
---|
[969b3fe] | 331 | lock( &this_processor->cltr->ready_queue_lock DEBUG_CTX2 ); |
---|
| 332 | append( &this_processor->cltr->ready_queue, thrd ); |
---|
| 333 | unlock( &this_processor->cltr->ready_queue_lock ); |
---|
[1c273d0] | 334 | |
---|
| 335 | verify( disable_preempt_count > 0 ); |
---|
[db6f06a] | 336 | } |
---|
| 337 | |
---|
[348006f] | 338 | thread_desc * nextThread(cluster * this) { |
---|
[1c273d0] | 339 | verify( disable_preempt_count > 0 ); |
---|
[e60e0dc] | 340 | lock( &this->ready_queue_lock DEBUG_CTX2 ); |
---|
[348006f] | 341 | thread_desc * head = pop_head( &this->ready_queue ); |
---|
[e60e0dc] | 342 | unlock( &this->ready_queue_lock ); |
---|
[1c273d0] | 343 | verify( disable_preempt_count > 0 ); |
---|
[db6f06a] | 344 | return head; |
---|
[eb2e723] | 345 | } |
---|
| 346 | |
---|
[82ff5845] | 347 | void BlockInternal() { |
---|
| 348 | disable_interrupts(); |
---|
[0b33412] | 349 | verify( disable_preempt_count > 0 ); |
---|
[75f3522] | 350 | suspend(); |
---|
[0b33412] | 351 | verify( disable_preempt_count > 0 ); |
---|
[2ac095d] | 352 | enable_interrupts( DEBUG_CTX ); |
---|
[75f3522] | 353 | } |
---|
| 354 | |
---|
[82ff5845] | 355 | void BlockInternal( spinlock * lock ) { |
---|
| 356 | disable_interrupts(); |
---|
[89a3df5] | 357 | this_processor->finish.action_code = Release; |
---|
| 358 | this_processor->finish.lock = lock; |
---|
[0b33412] | 359 | |
---|
| 360 | verify( disable_preempt_count > 0 ); |
---|
[db6f06a] | 361 | suspend(); |
---|
[0b33412] | 362 | verify( disable_preempt_count > 0 ); |
---|
| 363 | |
---|
[2ac095d] | 364 | enable_interrupts( DEBUG_CTX ); |
---|
[db6f06a] | 365 | } |
---|
| 366 | |
---|
[82ff5845] | 367 | void BlockInternal( thread_desc * thrd ) { |
---|
| 368 | disable_interrupts(); |
---|
[1c273d0] | 369 | assert( thrd->cor.state != Halted ); |
---|
[89a3df5] | 370 | this_processor->finish.action_code = Schedule; |
---|
| 371 | this_processor->finish.thrd = thrd; |
---|
[0b33412] | 372 | |
---|
| 373 | verify( disable_preempt_count > 0 ); |
---|
[db6f06a] | 374 | suspend(); |
---|
[0b33412] | 375 | verify( disable_preempt_count > 0 ); |
---|
| 376 | |
---|
[2ac095d] | 377 | enable_interrupts( DEBUG_CTX ); |
---|
[db6f06a] | 378 | } |
---|
| 379 | |
---|
[82ff5845] | 380 | void BlockInternal( spinlock * lock, thread_desc * thrd ) { |
---|
| 381 | disable_interrupts(); |
---|
[89a3df5] | 382 | this_processor->finish.action_code = Release_Schedule; |
---|
| 383 | this_processor->finish.lock = lock; |
---|
| 384 | this_processor->finish.thrd = thrd; |
---|
[0b33412] | 385 | |
---|
| 386 | verify( disable_preempt_count > 0 ); |
---|
[db6f06a] | 387 | suspend(); |
---|
[0b33412] | 388 | verify( disable_preempt_count > 0 ); |
---|
| 389 | |
---|
[2ac095d] | 390 | enable_interrupts( DEBUG_CTX ); |
---|
[eb2e723] | 391 | } |
---|
| 392 | |
---|
[82ff5845] | 393 | void BlockInternal(spinlock ** locks, unsigned short count) { |
---|
| 394 | disable_interrupts(); |
---|
[0c78741] | 395 | this_processor->finish.action_code = Release_Multi; |
---|
| 396 | this_processor->finish.locks = locks; |
---|
| 397 | this_processor->finish.lock_count = count; |
---|
[0b33412] | 398 | |
---|
| 399 | verify( disable_preempt_count > 0 ); |
---|
[0c78741] | 400 | suspend(); |
---|
[0b33412] | 401 | verify( disable_preempt_count > 0 ); |
---|
| 402 | |
---|
[2ac095d] | 403 | enable_interrupts( DEBUG_CTX ); |
---|
[0c78741] | 404 | } |
---|
| 405 | |
---|
[82ff5845] | 406 | void BlockInternal(spinlock ** locks, unsigned short lock_count, thread_desc ** thrds, unsigned short thrd_count) { |
---|
| 407 | disable_interrupts(); |
---|
[0c78741] | 408 | this_processor->finish.action_code = Release_Multi_Schedule; |
---|
| 409 | this_processor->finish.locks = locks; |
---|
| 410 | this_processor->finish.lock_count = lock_count; |
---|
| 411 | this_processor->finish.thrds = thrds; |
---|
| 412 | this_processor->finish.thrd_count = thrd_count; |
---|
[0b33412] | 413 | |
---|
| 414 | verify( disable_preempt_count > 0 ); |
---|
[0c78741] | 415 | suspend(); |
---|
[0b33412] | 416 | verify( disable_preempt_count > 0 ); |
---|
| 417 | |
---|
[2ac095d] | 418 | enable_interrupts( DEBUG_CTX ); |
---|
[0c78741] | 419 | } |
---|
| 420 | |
---|
[f2b12406] | 421 | void LeaveThread(spinlock * lock, thread_desc * thrd) { |
---|
| 422 | verify( disable_preempt_count > 0 ); |
---|
| 423 | this_processor->finish.action_code = thrd ? Release_Schedule : Release; |
---|
| 424 | this_processor->finish.lock = lock; |
---|
| 425 | this_processor->finish.thrd = thrd; |
---|
| 426 | |
---|
| 427 | suspend(); |
---|
| 428 | } |
---|
| 429 | |
---|
[fa21ac9] | 430 | //============================================================================================= |
---|
| 431 | // Kernel Setup logic |
---|
| 432 | //============================================================================================= |
---|
[eb2e723] | 433 | //----------------------------------------------------------------------------- |
---|
| 434 | // Kernel boot procedures |
---|
| 435 | void kernel_startup(void) { |
---|
[1c273d0] | 436 | LIB_DEBUG_PRINT_SAFE("Kernel : Starting\n"); |
---|
[eb2e723] | 437 | |
---|
| 438 | // Start by initializing the main thread |
---|
[1c273d0] | 439 | // SKULLDUGGERY: the mainThread steals the process main thread |
---|
[969b3fe] | 440 | // which will then be scheduled by the mainProcessor normally |
---|
| 441 | mainThread = (thread_desc *)&storage_mainThread; |
---|
[8fcbb4c] | 442 | current_stack_info_t info; |
---|
[83a071f9] | 443 | (*mainThread){ &info }; |
---|
[eb2e723] | 444 | |
---|
[fa21ac9] | 445 | LIB_DEBUG_PRINT_SAFE("Kernel : Main thread ready\n"); |
---|
| 446 | |
---|
[969b3fe] | 447 | // Initialize the main cluster |
---|
| 448 | mainCluster = (cluster *)&storage_mainCluster; |
---|
[9236060] | 449 | (*mainCluster){}; |
---|
[bd98b58] | 450 | |
---|
[969b3fe] | 451 | LIB_DEBUG_PRINT_SAFE("Kernel : main cluster ready\n"); |
---|
[fa21ac9] | 452 | |
---|
[969b3fe] | 453 | // Initialize the main processor and the main processor ctx |
---|
[eb2e723] | 454 | // (the coroutine that contains the processing control flow) |
---|
[969b3fe] | 455 | mainProcessor = (processor *)&storage_mainProcessor; |
---|
[9236060] | 456 | (*mainProcessor){ mainCluster, *(processorCtx_t *)&storage_mainProcessorCtx }; |
---|
[eb2e723] | 457 | |
---|
[dcb42b8] | 458 | //initialize the global state variables |
---|
[969b3fe] | 459 | this_processor = mainProcessor; |
---|
[1c273d0] | 460 | this_thread = mainThread; |
---|
| 461 | this_coroutine = &mainThread->cor; |
---|
[eb2e723] | 462 | |
---|
[82ff5845] | 463 | // Enable preemption |
---|
| 464 | kernel_start_preemption(); |
---|
| 465 | |
---|
[969b3fe] | 466 | // Add the main thread to the ready queue |
---|
| 467 | // once resume is called on mainProcessor->runner the mainThread needs to be scheduled like any normal thread |
---|
| 468 | ScheduleThread(mainThread); |
---|
| 469 | |
---|
| 470 | // SKULLDUGGERY: Force a context switch to the main processor to set the main thread's context to the current UNIX |
---|
[dcb42b8] | 471 | // context. Hence, the main thread does not begin through CtxInvokeThread, like all other threads. The trick here is that |
---|
[1c273d0] | 472 | // mainThread is on the ready queue when this call is made. |
---|
[9236060] | 473 | resume( *mainProcessor->runner ); |
---|
[eb2e723] | 474 | |
---|
[dcb42b8] | 475 | |
---|
| 476 | |
---|
| 477 | // THE SYSTEM IS NOW COMPLETELY RUNNING |
---|
[9d944b2] | 478 | LIB_DEBUG_PRINT_SAFE("Kernel : Started\n--------------------------------------------------\n\n"); |
---|
[82ff5845] | 479 | |
---|
[2ac095d] | 480 | enable_interrupts( DEBUG_CTX ); |
---|
[eb2e723] | 481 | } |
---|
| 482 | |
---|
[dcb42b8] | 483 | void kernel_shutdown(void) { |
---|
[9d944b2] | 484 | LIB_DEBUG_PRINT_SAFE("\n--------------------------------------------------\nKernel : Shutting down\n"); |
---|
[eb2e723] | 485 | |
---|
[4e6fb8e] | 486 | disable_interrupts(); |
---|
| 487 | |
---|
[969b3fe] | 488 | // SKULLDUGGERY: Notify the mainProcessor it needs to terminates. |
---|
[dcb42b8] | 489 | // When its coroutine terminates, it return control to the mainThread |
---|
| 490 | // which is currently here |
---|
[969b3fe] | 491 | mainProcessor->do_terminate = true; |
---|
[eb2e723] | 492 | suspend(); |
---|
| 493 | |
---|
[dcb42b8] | 494 | // THE SYSTEM IS NOW COMPLETELY STOPPED |
---|
[eb2e723] | 495 | |
---|
[82ff5845] | 496 | // Disable preemption |
---|
| 497 | kernel_stop_preemption(); |
---|
| 498 | |
---|
[969b3fe] | 499 | // Destroy the main processor and its context in reverse order of construction |
---|
[dcb42b8] | 500 | // These were manually constructed so we need manually destroy them |
---|
[9236060] | 501 | ^(*mainProcessor->runner){}; |
---|
[969b3fe] | 502 | ^(mainProcessor){}; |
---|
[eb2e723] | 503 | |
---|
[dcb42b8] | 504 | // Final step, destroy the main thread since it is no longer needed |
---|
| 505 | // Since we provided a stack to this taxk it will not destroy anything |
---|
[eb2e723] | 506 | ^(mainThread){}; |
---|
| 507 | |
---|
[1c273d0] | 508 | LIB_DEBUG_PRINT_SAFE("Kernel : Shutdown complete\n"); |
---|
[9d944b2] | 509 | } |
---|
| 510 | |
---|
| 511 | static spinlock kernel_abort_lock; |
---|
| 512 | static spinlock kernel_debug_lock; |
---|
| 513 | static bool kernel_abort_called = false; |
---|
| 514 | |
---|
| 515 | void * kernel_abort (void) __attribute__ ((__nothrow__)) { |
---|
| 516 | // abort cannot be recursively entered by the same or different processors because all signal handlers return when |
---|
| 517 | // the globalAbort flag is true. |
---|
[2ac095d] | 518 | lock( &kernel_abort_lock DEBUG_CTX2 ); |
---|
[9d944b2] | 519 | |
---|
| 520 | // first task to abort ? |
---|
| 521 | if ( !kernel_abort_called ) { // not first task to abort ? |
---|
| 522 | kernel_abort_called = true; |
---|
| 523 | unlock( &kernel_abort_lock ); |
---|
[1c273d0] | 524 | } |
---|
[9d944b2] | 525 | else { |
---|
| 526 | unlock( &kernel_abort_lock ); |
---|
[1c273d0] | 527 | |
---|
[9d944b2] | 528 | sigset_t mask; |
---|
| 529 | sigemptyset( &mask ); |
---|
| 530 | sigaddset( &mask, SIGALRM ); // block SIGALRM signals |
---|
| 531 | sigaddset( &mask, SIGUSR1 ); // block SIGUSR1 signals |
---|
| 532 | sigsuspend( &mask ); // block the processor to prevent further damage during abort |
---|
[1c273d0] | 533 | _exit( EXIT_FAILURE ); // if processor unblocks before it is killed, terminate it |
---|
[9d944b2] | 534 | } |
---|
| 535 | |
---|
[1c273d0] | 536 | return this_thread; |
---|
[9d944b2] | 537 | } |
---|
| 538 | |
---|
| 539 | void kernel_abort_msg( void * kernel_data, char * abort_text, int abort_text_size ) { |
---|
| 540 | thread_desc * thrd = kernel_data; |
---|
| 541 | |
---|
| 542 | int len = snprintf( abort_text, abort_text_size, "Error occurred while executing task %.256s (%p)", thrd->cor.name, thrd ); |
---|
| 543 | __lib_debug_write( STDERR_FILENO, abort_text, len ); |
---|
| 544 | |
---|
[1c273d0] | 545 | if ( thrd != this_coroutine ) { |
---|
| 546 | len = snprintf( abort_text, abort_text_size, " in coroutine %.256s (%p).\n", this_coroutine->name, this_coroutine ); |
---|
[9d944b2] | 547 | __lib_debug_write( STDERR_FILENO, abort_text, len ); |
---|
[1c273d0] | 548 | } |
---|
[9d944b2] | 549 | else { |
---|
| 550 | __lib_debug_write( STDERR_FILENO, ".\n", 2 ); |
---|
| 551 | } |
---|
| 552 | } |
---|
| 553 | |
---|
| 554 | extern "C" { |
---|
| 555 | void __lib_debug_acquire() { |
---|
[2ac095d] | 556 | lock( &kernel_debug_lock DEBUG_CTX2 ); |
---|
[9d944b2] | 557 | } |
---|
| 558 | |
---|
| 559 | void __lib_debug_release() { |
---|
[2ac095d] | 560 | unlock( &kernel_debug_lock ); |
---|
[9d944b2] | 561 | } |
---|
[8118303] | 562 | } |
---|
| 563 | |
---|
[fa21ac9] | 564 | //============================================================================================= |
---|
| 565 | // Kernel Utilities |
---|
| 566 | //============================================================================================= |
---|
[bd98b58] | 567 | //----------------------------------------------------------------------------- |
---|
| 568 | // Locks |
---|
[242a902] | 569 | void ?{}( spinlock & this ) { |
---|
| 570 | this.lock = 0; |
---|
[bd98b58] | 571 | } |
---|
[242a902] | 572 | void ^?{}( spinlock & this ) { |
---|
[bd98b58] | 573 | |
---|
[db6f06a] | 574 | } |
---|
| 575 | |
---|
[2ac095d] | 576 | bool try_lock( spinlock * this DEBUG_CTX_PARAM2 ) { |
---|
[b227f68] | 577 | return this->lock == 0 && __sync_lock_test_and_set_4( &this->lock, 1 ) == 0; |
---|
[c81ebf9] | 578 | } |
---|
| 579 | |
---|
[2ac095d] | 580 | void lock( spinlock * this DEBUG_CTX_PARAM2 ) { |
---|
[db6f06a] | 581 | for ( unsigned int i = 1;; i += 1 ) { |
---|
[b227f68] | 582 | if ( this->lock == 0 && __sync_lock_test_and_set_4( &this->lock, 1 ) == 0 ) { break; } |
---|
[db6f06a] | 583 | } |
---|
[b227f68] | 584 | LIB_DEBUG_DO( |
---|
| 585 | this->prev_name = caller; |
---|
| 586 | this->prev_thrd = this_thread; |
---|
| 587 | ) |
---|
[db6f06a] | 588 | } |
---|
[bd98b58] | 589 | |
---|
[b227f68] | 590 | void lock_yield( spinlock * this DEBUG_CTX_PARAM2 ) { |
---|
| 591 | for ( unsigned int i = 1;; i += 1 ) { |
---|
| 592 | if ( this->lock == 0 && __sync_lock_test_and_set_4( &this->lock, 1 ) == 0 ) { break; } |
---|
| 593 | yield(); |
---|
| 594 | } |
---|
| 595 | LIB_DEBUG_DO( |
---|
| 596 | this->prev_name = caller; |
---|
| 597 | this->prev_thrd = this_thread; |
---|
| 598 | ) |
---|
| 599 | } |
---|
| 600 | |
---|
| 601 | |
---|
[db6f06a] | 602 | void unlock( spinlock * this ) { |
---|
| 603 | __sync_lock_release_4( &this->lock ); |
---|
[bd98b58] | 604 | } |
---|
| 605 | |
---|
[242a902] | 606 | void ?{}( semaphore & this, int count = 1 ) { |
---|
| 607 | (this.lock){}; |
---|
| 608 | this.count = count; |
---|
| 609 | (this.waiting){}; |
---|
[db6f06a] | 610 | } |
---|
[242a902] | 611 | void ^?{}(semaphore & this) {} |
---|
[db6f06a] | 612 | |
---|
[bdeba0b] | 613 | void P(semaphore * this) { |
---|
[2ac095d] | 614 | lock( &this->lock DEBUG_CTX2 ); |
---|
[bdeba0b] | 615 | this->count -= 1; |
---|
| 616 | if ( this->count < 0 ) { |
---|
| 617 | // queue current task |
---|
| 618 | append( &this->waiting, (thread_desc *)this_thread ); |
---|
| 619 | |
---|
| 620 | // atomically release spin lock and block |
---|
[82ff5845] | 621 | BlockInternal( &this->lock ); |
---|
[8def349] | 622 | } |
---|
[4e6fb8e] | 623 | else { |
---|
[bdeba0b] | 624 | unlock( &this->lock ); |
---|
[4e6fb8e] | 625 | } |
---|
[bd98b58] | 626 | } |
---|
| 627 | |
---|
[bdeba0b] | 628 | void V(semaphore * this) { |
---|
| 629 | thread_desc * thrd = NULL; |
---|
[2ac095d] | 630 | lock( &this->lock DEBUG_CTX2 ); |
---|
[bdeba0b] | 631 | this->count += 1; |
---|
| 632 | if ( this->count <= 0 ) { |
---|
| 633 | // remove task at head of waiting list |
---|
| 634 | thrd = pop_head( &this->waiting ); |
---|
[bd98b58] | 635 | } |
---|
[bdeba0b] | 636 | |
---|
[db6f06a] | 637 | unlock( &this->lock ); |
---|
[bdeba0b] | 638 | |
---|
| 639 | // make new owner |
---|
| 640 | WakeThread( thrd ); |
---|
[bd98b58] | 641 | } |
---|
| 642 | |
---|
| 643 | //----------------------------------------------------------------------------- |
---|
| 644 | // Queues |
---|
[242a902] | 645 | void ?{}( __thread_queue_t & this ) { |
---|
| 646 | this.head = NULL; |
---|
| 647 | this.tail = &this.head; |
---|
[bd98b58] | 648 | } |
---|
| 649 | |
---|
[5ea06d6] | 650 | void append( __thread_queue_t * this, thread_desc * t ) { |
---|
[4aa2fb2] | 651 | verify(this->tail != NULL); |
---|
[bd98b58] | 652 | *this->tail = t; |
---|
| 653 | this->tail = &t->next; |
---|
| 654 | } |
---|
| 655 | |
---|
[5ea06d6] | 656 | thread_desc * pop_head( __thread_queue_t * this ) { |
---|
[348006f] | 657 | thread_desc * head = this->head; |
---|
[bd98b58] | 658 | if( head ) { |
---|
| 659 | this->head = head->next; |
---|
| 660 | if( !head->next ) { |
---|
| 661 | this->tail = &this->head; |
---|
| 662 | } |
---|
| 663 | head->next = NULL; |
---|
[1c273d0] | 664 | } |
---|
[bd98b58] | 665 | return head; |
---|
| 666 | } |
---|
[690f13c] | 667 | |
---|
[242a902] | 668 | void ?{}( __condition_stack_t & this ) { |
---|
| 669 | this.top = NULL; |
---|
[690f13c] | 670 | } |
---|
| 671 | |
---|
[0c78741] | 672 | void push( __condition_stack_t * this, __condition_criterion_t * t ) { |
---|
[4aa2fb2] | 673 | verify( !t->next ); |
---|
[690f13c] | 674 | t->next = this->top; |
---|
| 675 | this->top = t; |
---|
| 676 | } |
---|
| 677 | |
---|
[0c78741] | 678 | __condition_criterion_t * pop( __condition_stack_t * this ) { |
---|
| 679 | __condition_criterion_t * top = this->top; |
---|
[690f13c] | 680 | if( top ) { |
---|
| 681 | this->top = top->next; |
---|
| 682 | top->next = NULL; |
---|
[1c273d0] | 683 | } |
---|
[690f13c] | 684 | return top; |
---|
| 685 | } |
---|
[6b0b624] | 686 | |
---|
[8118303] | 687 | // Local Variables: // |
---|
| 688 | // mode: c // |
---|
| 689 | // tab-width: 4 // |
---|
| 690 | // End: // |
---|