1 /* 2 * kmp_tasking.cpp -- OpenMP 3.0 tasking support. 3 */ 4 5 //===----------------------------------------------------------------------===// 6 // 7 // The LLVM Compiler Infrastructure 8 // 9 // This file is dual licensed under the MIT and the University of Illinois Open 10 // Source Licenses. See LICENSE.txt for details. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "kmp.h" 15 #include "kmp_i18n.h" 16 #include "kmp_itt.h" 17 #include "kmp_stats.h" 18 #include "kmp_wait_release.h" 19 20 #if OMPT_SUPPORT 21 #include "ompt-specific.h" 22 #endif 23 24 #include "tsan_annotations.h" 25 26 /* forward declaration */ 27 static void __kmp_enable_tasking(kmp_task_team_t *task_team, 28 kmp_info_t *this_thr); 29 static void __kmp_alloc_task_deque(kmp_info_t *thread, 30 kmp_thread_data_t *thread_data); 31 static int __kmp_realloc_task_threads_data(kmp_info_t *thread, 32 kmp_task_team_t *task_team); 33 34 #ifdef OMP_45_ENABLED 35 static void __kmp_bottom_half_finish_proxy(kmp_int32 gtid, kmp_task_t *ptask); 36 #endif 37 38 #ifdef BUILD_TIED_TASK_STACK 39 40 // __kmp_trace_task_stack: print the tied tasks from the task stack in order 41 // from top do bottom 42 // 43 // gtid: global thread identifier for thread containing stack 44 // thread_data: thread data for task team thread containing stack 45 // threshold: value above which the trace statement triggers 46 // location: string identifying call site of this function (for trace) 47 static void __kmp_trace_task_stack(kmp_int32 gtid, 48 kmp_thread_data_t *thread_data, 49 int threshold, char *location) { 50 kmp_task_stack_t *task_stack = &thread_data->td.td_susp_tied_tasks; 51 kmp_taskdata_t **stack_top = task_stack->ts_top; 52 kmp_int32 entries = task_stack->ts_entries; 53 kmp_taskdata_t *tied_task; 54 55 KA_TRACE( 56 threshold, 57 ("__kmp_trace_task_stack(start): location = %s, gtid = %d, entries = %d, " 58 "first_block = %p, stack_top = %p \n", 59 location, gtid, entries, task_stack->ts_first_block, stack_top)); 60 61 KMP_DEBUG_ASSERT(stack_top != NULL); 62 KMP_DEBUG_ASSERT(entries > 0); 63 64 while (entries != 0) { 65 KMP_DEBUG_ASSERT(stack_top != &task_stack->ts_first_block.sb_block[0]); 66 // fix up ts_top if we need to pop from previous block 67 if (entries & TASK_STACK_INDEX_MASK == 0) { 68 kmp_stack_block_t *stack_block = (kmp_stack_block_t *)(stack_top); 69 70 stack_block = stack_block->sb_prev; 71 stack_top = &stack_block->sb_block[TASK_STACK_BLOCK_SIZE]; 72 } 73 74 // finish bookkeeping 75 stack_top--; 76 entries--; 77 78 tied_task = *stack_top; 79 80 KMP_DEBUG_ASSERT(tied_task != NULL); 81 KMP_DEBUG_ASSERT(tied_task->td_flags.tasktype == TASK_TIED); 82 83 KA_TRACE(threshold, 84 ("__kmp_trace_task_stack(%s): gtid=%d, entry=%d, " 85 "stack_top=%p, tied_task=%p\n", 86 location, gtid, entries, stack_top, tied_task)); 87 } 88 KMP_DEBUG_ASSERT(stack_top == &task_stack->ts_first_block.sb_block[0]); 89 90 KA_TRACE(threshold, 91 ("__kmp_trace_task_stack(exit): location = %s, gtid = %d\n", 92 location, gtid)); 93 } 94 95 // __kmp_init_task_stack: initialize the task stack for the first time 96 // after a thread_data structure is created. 97 // It should not be necessary to do this again (assuming the stack works). 98 // 99 // gtid: global thread identifier of calling thread 100 // thread_data: thread data for task team thread containing stack 101 static void __kmp_init_task_stack(kmp_int32 gtid, 102 kmp_thread_data_t *thread_data) { 103 kmp_task_stack_t *task_stack = &thread_data->td.td_susp_tied_tasks; 104 kmp_stack_block_t *first_block; 105 106 // set up the first block of the stack 107 first_block = &task_stack->ts_first_block; 108 task_stack->ts_top = (kmp_taskdata_t **)first_block; 109 memset((void *)first_block, '\0', 110 TASK_STACK_BLOCK_SIZE * sizeof(kmp_taskdata_t *)); 111 112 // initialize the stack to be empty 113 task_stack->ts_entries = TASK_STACK_EMPTY; 114 first_block->sb_next = NULL; 115 first_block->sb_prev = NULL; 116 } 117 118 // __kmp_free_task_stack: free the task stack when thread_data is destroyed. 119 // 120 // gtid: global thread identifier for calling thread 121 // thread_data: thread info for thread containing stack 122 static void __kmp_free_task_stack(kmp_int32 gtid, 123 kmp_thread_data_t *thread_data) { 124 kmp_task_stack_t *task_stack = &thread_data->td.td_susp_tied_tasks; 125 kmp_stack_block_t *stack_block = &task_stack->ts_first_block; 126 127 KMP_DEBUG_ASSERT(task_stack->ts_entries == TASK_STACK_EMPTY); 128 // free from the second block of the stack 129 while (stack_block != NULL) { 130 kmp_stack_block_t *next_block = (stack_block) ? stack_block->sb_next : NULL; 131 132 stack_block->sb_next = NULL; 133 stack_block->sb_prev = NULL; 134 if (stack_block != &task_stack->ts_first_block) { 135 __kmp_thread_free(thread, 136 stack_block); // free the block, if not the first 137 } 138 stack_block = next_block; 139 } 140 // initialize the stack to be empty 141 task_stack->ts_entries = 0; 142 task_stack->ts_top = NULL; 143 } 144 145 // __kmp_push_task_stack: Push the tied task onto the task stack. 146 // Grow the stack if necessary by allocating another block. 147 // 148 // gtid: global thread identifier for calling thread 149 // thread: thread info for thread containing stack 150 // tied_task: the task to push on the stack 151 static void __kmp_push_task_stack(kmp_int32 gtid, kmp_info_t *thread, 152 kmp_taskdata_t *tied_task) { 153 // GEH - need to consider what to do if tt_threads_data not allocated yet 154 kmp_thread_data_t *thread_data = 155 &thread->th.th_task_team->tt.tt_threads_data[__kmp_tid_from_gtid(gtid)]; 156 kmp_task_stack_t *task_stack = &thread_data->td.td_susp_tied_tasks; 157 158 if (tied_task->td_flags.team_serial || tied_task->td_flags.tasking_ser) { 159 return; // Don't push anything on stack if team or team tasks are serialized 160 } 161 162 KMP_DEBUG_ASSERT(tied_task->td_flags.tasktype == TASK_TIED); 163 KMP_DEBUG_ASSERT(task_stack->ts_top != NULL); 164 165 KA_TRACE(20, 166 ("__kmp_push_task_stack(enter): GTID: %d; THREAD: %p; TASK: %p\n", 167 gtid, thread, tied_task)); 168 // Store entry 169 *(task_stack->ts_top) = tied_task; 170 171 // Do bookkeeping for next push 172 task_stack->ts_top++; 173 task_stack->ts_entries++; 174 175 if (task_stack->ts_entries & TASK_STACK_INDEX_MASK == 0) { 176 // Find beginning of this task block 177 kmp_stack_block_t *stack_block = 178 (kmp_stack_block_t *)(task_stack->ts_top - TASK_STACK_BLOCK_SIZE); 179 180 // Check if we already have a block 181 if (stack_block->sb_next != 182 NULL) { // reset ts_top to beginning of next block 183 task_stack->ts_top = &stack_block->sb_next->sb_block[0]; 184 } else { // Alloc new block and link it up 185 kmp_stack_block_t *new_block = (kmp_stack_block_t *)__kmp_thread_calloc( 186 thread, sizeof(kmp_stack_block_t)); 187 188 task_stack->ts_top = &new_block->sb_block[0]; 189 stack_block->sb_next = new_block; 190 new_block->sb_prev = stack_block; 191 new_block->sb_next = NULL; 192 193 KA_TRACE( 194 30, 195 ("__kmp_push_task_stack(): GTID: %d; TASK: %p; Alloc new block: %p\n", 196 gtid, tied_task, new_block)); 197 } 198 } 199 KA_TRACE(20, ("__kmp_push_task_stack(exit): GTID: %d; TASK: %p\n", gtid, 200 tied_task)); 201 } 202 203 // __kmp_pop_task_stack: Pop the tied task from the task stack. Don't return 204 // the task, just check to make sure it matches the ending task passed in. 205 // 206 // gtid: global thread identifier for the calling thread 207 // thread: thread info structure containing stack 208 // tied_task: the task popped off the stack 209 // ending_task: the task that is ending (should match popped task) 210 static void __kmp_pop_task_stack(kmp_int32 gtid, kmp_info_t *thread, 211 kmp_taskdata_t *ending_task) { 212 // GEH - need to consider what to do if tt_threads_data not allocated yet 213 kmp_thread_data_t *thread_data = 214 &thread->th.th_task_team->tt_threads_data[__kmp_tid_from_gtid(gtid)]; 215 kmp_task_stack_t *task_stack = &thread_data->td.td_susp_tied_tasks; 216 kmp_taskdata_t *tied_task; 217 218 if (ending_task->td_flags.team_serial || ending_task->td_flags.tasking_ser) { 219 // Don't pop anything from stack if team or team tasks are serialized 220 return; 221 } 222 223 KMP_DEBUG_ASSERT(task_stack->ts_top != NULL); 224 KMP_DEBUG_ASSERT(task_stack->ts_entries > 0); 225 226 KA_TRACE(20, ("__kmp_pop_task_stack(enter): GTID: %d; THREAD: %p\n", gtid, 227 thread)); 228 229 // fix up ts_top if we need to pop from previous block 230 if (task_stack->ts_entries & TASK_STACK_INDEX_MASK == 0) { 231 kmp_stack_block_t *stack_block = (kmp_stack_block_t *)(task_stack->ts_top); 232 233 stack_block = stack_block->sb_prev; 234 task_stack->ts_top = &stack_block->sb_block[TASK_STACK_BLOCK_SIZE]; 235 } 236 237 // finish bookkeeping 238 task_stack->ts_top--; 239 task_stack->ts_entries--; 240 241 tied_task = *(task_stack->ts_top); 242 243 KMP_DEBUG_ASSERT(tied_task != NULL); 244 KMP_DEBUG_ASSERT(tied_task->td_flags.tasktype == TASK_TIED); 245 KMP_DEBUG_ASSERT(tied_task == ending_task); // If we built the stack correctly 246 247 KA_TRACE(20, ("__kmp_pop_task_stack(exit): GTID: %d; TASK: %p\n", gtid, 248 tied_task)); 249 return; 250 } 251 #endif /* BUILD_TIED_TASK_STACK */ 252 253 // __kmp_push_task: Add a task to the thread's deque 254 static kmp_int32 __kmp_push_task(kmp_int32 gtid, kmp_task_t *task) { 255 kmp_info_t *thread = __kmp_threads[gtid]; 256 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 257 kmp_task_team_t *task_team = thread->th.th_task_team; 258 kmp_int32 tid = __kmp_tid_from_gtid(gtid); 259 kmp_thread_data_t *thread_data; 260 261 KA_TRACE(20, 262 ("__kmp_push_task: T#%d trying to push task %p.\n", gtid, taskdata)); 263 264 if (taskdata->td_flags.tiedness == TASK_UNTIED) { 265 // untied task needs to increment counter so that the task structure is not 266 // freed prematurely 267 kmp_int32 counter = 1 + KMP_TEST_THEN_INC32(&taskdata->td_untied_count); 268 KA_TRACE( 269 20, 270 ("__kmp_push_task: T#%d untied_count (%d) incremented for task %p\n", 271 gtid, counter, taskdata)); 272 } 273 274 // The first check avoids building task_team thread data if serialized 275 if (taskdata->td_flags.task_serial) { 276 KA_TRACE(20, ("__kmp_push_task: T#%d team serialized; returning " 277 "TASK_NOT_PUSHED for task %p\n", 278 gtid, taskdata)); 279 return TASK_NOT_PUSHED; 280 } 281 282 // Now that serialized tasks have returned, we can assume that we are not in 283 // immediate exec mode 284 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 285 if (!KMP_TASKING_ENABLED(task_team)) { 286 __kmp_enable_tasking(task_team, thread); 287 } 288 KMP_DEBUG_ASSERT(TCR_4(task_team->tt.tt_found_tasks) == TRUE); 289 KMP_DEBUG_ASSERT(TCR_PTR(task_team->tt.tt_threads_data) != NULL); 290 291 // Find tasking deque specific to encountering thread 292 thread_data = &task_team->tt.tt_threads_data[tid]; 293 294 // No lock needed since only owner can allocate 295 if (thread_data->td.td_deque == NULL) { 296 __kmp_alloc_task_deque(thread, thread_data); 297 } 298 299 // Check if deque is full 300 if (TCR_4(thread_data->td.td_deque_ntasks) >= 301 TASK_DEQUE_SIZE(thread_data->td)) { 302 KA_TRACE(20, ("__kmp_push_task: T#%d deque is full; returning " 303 "TASK_NOT_PUSHED for task %p\n", 304 gtid, taskdata)); 305 return TASK_NOT_PUSHED; 306 } 307 308 // Lock the deque for the task push operation 309 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 310 311 #if OMP_45_ENABLED 312 // Need to recheck as we can get a proxy task from a thread outside of OpenMP 313 if (TCR_4(thread_data->td.td_deque_ntasks) >= 314 TASK_DEQUE_SIZE(thread_data->td)) { 315 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 316 KA_TRACE(20, ("__kmp_push_task: T#%d deque is full on 2nd check; returning " 317 "TASK_NOT_PUSHED for task %p\n", 318 gtid, taskdata)); 319 return TASK_NOT_PUSHED; 320 } 321 #else 322 // Must have room since no thread can add tasks but calling thread 323 KMP_DEBUG_ASSERT(TCR_4(thread_data->td.td_deque_ntasks) < 324 TASK_DEQUE_SIZE(thread_data->td)); 325 #endif 326 327 thread_data->td.td_deque[thread_data->td.td_deque_tail] = 328 taskdata; // Push taskdata 329 // Wrap index. 330 thread_data->td.td_deque_tail = 331 (thread_data->td.td_deque_tail + 1) & TASK_DEQUE_MASK(thread_data->td); 332 TCW_4(thread_data->td.td_deque_ntasks, 333 TCR_4(thread_data->td.td_deque_ntasks) + 1); // Adjust task count 334 335 KA_TRACE(20, ("__kmp_push_task: T#%d returning TASK_SUCCESSFULLY_PUSHED: " 336 "task=%p ntasks=%d head=%u tail=%u\n", 337 gtid, taskdata, thread_data->td.td_deque_ntasks, 338 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 339 340 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 341 342 return TASK_SUCCESSFULLY_PUSHED; 343 } 344 345 // __kmp_pop_current_task_from_thread: set up current task from called thread 346 // when team ends 347 // 348 // this_thr: thread structure to set current_task in. 349 void __kmp_pop_current_task_from_thread(kmp_info_t *this_thr) { 350 KF_TRACE(10, ("__kmp_pop_current_task_from_thread(enter): T#%d " 351 "this_thread=%p, curtask=%p, " 352 "curtask_parent=%p\n", 353 0, this_thr, this_thr->th.th_current_task, 354 this_thr->th.th_current_task->td_parent)); 355 356 this_thr->th.th_current_task = this_thr->th.th_current_task->td_parent; 357 358 KF_TRACE(10, ("__kmp_pop_current_task_from_thread(exit): T#%d " 359 "this_thread=%p, curtask=%p, " 360 "curtask_parent=%p\n", 361 0, this_thr, this_thr->th.th_current_task, 362 this_thr->th.th_current_task->td_parent)); 363 } 364 365 // __kmp_push_current_task_to_thread: set up current task in called thread for a 366 // new team 367 // 368 // this_thr: thread structure to set up 369 // team: team for implicit task data 370 // tid: thread within team to set up 371 void __kmp_push_current_task_to_thread(kmp_info_t *this_thr, kmp_team_t *team, 372 int tid) { 373 // current task of the thread is a parent of the new just created implicit 374 // tasks of new team 375 KF_TRACE(10, ("__kmp_push_current_task_to_thread(enter): T#%d this_thread=%p " 376 "curtask=%p " 377 "parent_task=%p\n", 378 tid, this_thr, this_thr->th.th_current_task, 379 team->t.t_implicit_task_taskdata[tid].td_parent)); 380 381 KMP_DEBUG_ASSERT(this_thr != NULL); 382 383 if (tid == 0) { 384 if (this_thr->th.th_current_task != &team->t.t_implicit_task_taskdata[0]) { 385 team->t.t_implicit_task_taskdata[0].td_parent = 386 this_thr->th.th_current_task; 387 this_thr->th.th_current_task = &team->t.t_implicit_task_taskdata[0]; 388 } 389 } else { 390 team->t.t_implicit_task_taskdata[tid].td_parent = 391 team->t.t_implicit_task_taskdata[0].td_parent; 392 this_thr->th.th_current_task = &team->t.t_implicit_task_taskdata[tid]; 393 } 394 395 KF_TRACE(10, ("__kmp_push_current_task_to_thread(exit): T#%d this_thread=%p " 396 "curtask=%p " 397 "parent_task=%p\n", 398 tid, this_thr, this_thr->th.th_current_task, 399 team->t.t_implicit_task_taskdata[tid].td_parent)); 400 } 401 402 // __kmp_task_start: bookkeeping for a task starting execution 403 // 404 // GTID: global thread id of calling thread 405 // task: task starting execution 406 // current_task: task suspending 407 static void __kmp_task_start(kmp_int32 gtid, kmp_task_t *task, 408 kmp_taskdata_t *current_task) { 409 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 410 kmp_info_t *thread = __kmp_threads[gtid]; 411 412 KA_TRACE(10, 413 ("__kmp_task_start(enter): T#%d starting task %p: current_task=%p\n", 414 gtid, taskdata, current_task)); 415 416 KMP_DEBUG_ASSERT(taskdata->td_flags.tasktype == TASK_EXPLICIT); 417 418 // mark currently executing task as suspended 419 // TODO: GEH - make sure root team implicit task is initialized properly. 420 // KMP_DEBUG_ASSERT( current_task -> td_flags.executing == 1 ); 421 current_task->td_flags.executing = 0; 422 423 // Add task to stack if tied 424 #ifdef BUILD_TIED_TASK_STACK 425 if (taskdata->td_flags.tiedness == TASK_TIED) { 426 __kmp_push_task_stack(gtid, thread, taskdata); 427 } 428 #endif /* BUILD_TIED_TASK_STACK */ 429 430 // mark starting task as executing and as current task 431 thread->th.th_current_task = taskdata; 432 433 KMP_DEBUG_ASSERT(taskdata->td_flags.started == 0 || 434 taskdata->td_flags.tiedness == TASK_UNTIED); 435 KMP_DEBUG_ASSERT(taskdata->td_flags.executing == 0 || 436 taskdata->td_flags.tiedness == TASK_UNTIED); 437 taskdata->td_flags.started = 1; 438 taskdata->td_flags.executing = 1; 439 KMP_DEBUG_ASSERT(taskdata->td_flags.complete == 0); 440 KMP_DEBUG_ASSERT(taskdata->td_flags.freed == 0); 441 442 // GEH TODO: shouldn't we pass some sort of location identifier here? 443 // APT: yes, we will pass location here. 444 // need to store current thread state (in a thread or taskdata structure) 445 // before setting work_state, otherwise wrong state is set after end of task 446 447 KA_TRACE(10, ("__kmp_task_start(exit): T#%d task=%p\n", gtid, taskdata)); 448 449 return; 450 } 451 452 #if OMPT_SUPPORT 453 //------------------------------------------------------------------------------ 454 // __ompt_task_init: 455 // Initialize OMPT fields maintained by a task. This will only be called after 456 // ompt_start_tool, so we already know whether ompt is enabled or not. 457 458 static inline void __ompt_task_init(kmp_taskdata_t *task, int tid) { 459 // The calls to __ompt_task_init already have the ompt_enabled condition. 460 task->ompt_task_info.task_data.value = 0; 461 task->ompt_task_info.frame.exit_frame = NULL; 462 task->ompt_task_info.frame.enter_frame = NULL; 463 #if OMP_40_ENABLED 464 task->ompt_task_info.ndeps = 0; 465 task->ompt_task_info.deps = NULL; 466 #endif /* OMP_40_ENABLED */ 467 } 468 469 // __ompt_task_start: 470 // Build and trigger task-begin event 471 static inline void __ompt_task_start(kmp_task_t *task, 472 kmp_taskdata_t *current_task, 473 kmp_int32 gtid) { 474 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 475 ompt_task_status_t status = ompt_task_others; 476 if (__kmp_threads[gtid]->th.ompt_thread_info.ompt_task_yielded) { 477 status = ompt_task_yield; 478 __kmp_threads[gtid]->th.ompt_thread_info.ompt_task_yielded = 0; 479 } 480 /* let OMPT know that we're about to run this task */ 481 if (ompt_enabled.ompt_callback_task_schedule) { 482 ompt_callbacks.ompt_callback(ompt_callback_task_schedule)( 483 &(current_task->ompt_task_info.task_data), status, 484 &(taskdata->ompt_task_info.task_data)); 485 } 486 taskdata->ompt_task_info.scheduling_parent = current_task; 487 } 488 489 // __ompt_task_finish: 490 // Build and trigger final task-schedule event 491 static inline void __ompt_task_finish(kmp_task_t *task, 492 kmp_taskdata_t *resumed_task) { 493 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 494 ompt_task_status_t status = ompt_task_complete; 495 if (taskdata->td_flags.tiedness == TASK_UNTIED && 496 KMP_TEST_THEN_ADD32(&(taskdata->td_untied_count), 0) > 1) 497 status = ompt_task_others; 498 if (__kmp_omp_cancellation && taskdata->td_taskgroup && 499 taskdata->td_taskgroup->cancel_request == cancel_taskgroup) { 500 status = ompt_task_cancel; 501 } 502 503 /* let OMPT know that we're returning to the callee task */ 504 if (ompt_enabled.ompt_callback_task_schedule) { 505 ompt_callbacks.ompt_callback(ompt_callback_task_schedule)( 506 &(taskdata->ompt_task_info.task_data), status, 507 &((resumed_task ? resumed_task 508 : (taskdata->ompt_task_info.scheduling_parent 509 ? taskdata->ompt_task_info.scheduling_parent 510 : taskdata->td_parent)) 511 ->ompt_task_info.task_data)); 512 } 513 } 514 #endif 515 516 template <bool ompt> 517 static void __kmpc_omp_task_begin_if0_template(ident_t *loc_ref, kmp_int32 gtid, 518 kmp_task_t *task, 519 void *frame_address, 520 void *return_address) { 521 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 522 kmp_taskdata_t *current_task = __kmp_threads[gtid]->th.th_current_task; 523 524 KA_TRACE(10, ("__kmpc_omp_task_begin_if0(enter): T#%d loc=%p task=%p " 525 "current_task=%p\n", 526 gtid, loc_ref, taskdata, current_task)); 527 528 if (taskdata->td_flags.tiedness == TASK_UNTIED) { 529 // untied task needs to increment counter so that the task structure is not 530 // freed prematurely 531 kmp_int32 counter = 1 + KMP_TEST_THEN_INC32(&taskdata->td_untied_count); 532 KA_TRACE(20, ("__kmpc_omp_task_begin_if0: T#%d untied_count (%d) " 533 "incremented for task %p\n", 534 gtid, counter, taskdata)); 535 } 536 537 taskdata->td_flags.task_serial = 538 1; // Execute this task immediately, not deferred. 539 __kmp_task_start(gtid, task, current_task); 540 541 #if OMPT_SUPPORT 542 if (ompt) { 543 if (current_task->ompt_task_info.frame.enter_frame == NULL) { 544 current_task->ompt_task_info.frame.enter_frame = 545 taskdata->ompt_task_info.frame.exit_frame = frame_address; 546 } 547 if (ompt_enabled.ompt_callback_task_create) { 548 ompt_task_info_t *parent_info = &(current_task->ompt_task_info); 549 ompt_callbacks.ompt_callback(ompt_callback_task_create)( 550 &(parent_info->task_data), &(parent_info->frame), 551 &(taskdata->ompt_task_info.task_data), 552 ompt_task_explicit | TASK_TYPE_DETAILS_FORMAT(taskdata), 0, 553 return_address); 554 } 555 __ompt_task_start(task, current_task, gtid); 556 } 557 #endif // OMPT_SUPPORT 558 559 KA_TRACE(10, ("__kmpc_omp_task_begin_if0(exit): T#%d loc=%p task=%p,\n", gtid, 560 loc_ref, taskdata)); 561 } 562 563 #if OMPT_SUPPORT 564 OMPT_NOINLINE 565 static void __kmpc_omp_task_begin_if0_ompt(ident_t *loc_ref, kmp_int32 gtid, 566 kmp_task_t *task, 567 void *frame_address, 568 void *return_address) { 569 __kmpc_omp_task_begin_if0_template<true>(loc_ref, gtid, task, frame_address, 570 return_address); 571 } 572 #endif // OMPT_SUPPORT 573 574 // __kmpc_omp_task_begin_if0: report that a given serialized task has started 575 // execution 576 // 577 // loc_ref: source location information; points to beginning of task block. 578 // gtid: global thread number. 579 // task: task thunk for the started task. 580 void __kmpc_omp_task_begin_if0(ident_t *loc_ref, kmp_int32 gtid, 581 kmp_task_t *task) { 582 #if OMPT_SUPPORT 583 if (UNLIKELY(ompt_enabled.enabled)) { 584 OMPT_STORE_RETURN_ADDRESS(gtid); 585 __kmpc_omp_task_begin_if0_ompt(loc_ref, gtid, task, 586 OMPT_GET_FRAME_ADDRESS(1), 587 OMPT_LOAD_RETURN_ADDRESS(gtid)); 588 return; 589 } 590 #endif 591 __kmpc_omp_task_begin_if0_template<false>(loc_ref, gtid, task, NULL, NULL); 592 } 593 594 #ifdef TASK_UNUSED 595 // __kmpc_omp_task_begin: report that a given task has started execution 596 // NEVER GENERATED BY COMPILER, DEPRECATED!!! 597 void __kmpc_omp_task_begin(ident_t *loc_ref, kmp_int32 gtid, kmp_task_t *task) { 598 kmp_taskdata_t *current_task = __kmp_threads[gtid]->th.th_current_task; 599 600 KA_TRACE( 601 10, 602 ("__kmpc_omp_task_begin(enter): T#%d loc=%p task=%p current_task=%p\n", 603 gtid, loc_ref, KMP_TASK_TO_TASKDATA(task), current_task)); 604 605 __kmp_task_start(gtid, task, current_task); 606 607 KA_TRACE(10, ("__kmpc_omp_task_begin(exit): T#%d loc=%p task=%p,\n", gtid, 608 loc_ref, KMP_TASK_TO_TASKDATA(task))); 609 return; 610 } 611 #endif // TASK_UNUSED 612 613 // __kmp_free_task: free the current task space and the space for shareds 614 // 615 // gtid: Global thread ID of calling thread 616 // taskdata: task to free 617 // thread: thread data structure of caller 618 static void __kmp_free_task(kmp_int32 gtid, kmp_taskdata_t *taskdata, 619 kmp_info_t *thread) { 620 KA_TRACE(30, ("__kmp_free_task: T#%d freeing data from task %p\n", gtid, 621 taskdata)); 622 623 // Check to make sure all flags and counters have the correct values 624 KMP_DEBUG_ASSERT(taskdata->td_flags.tasktype == TASK_EXPLICIT); 625 KMP_DEBUG_ASSERT(taskdata->td_flags.executing == 0); 626 KMP_DEBUG_ASSERT(taskdata->td_flags.complete == 1); 627 KMP_DEBUG_ASSERT(taskdata->td_flags.freed == 0); 628 KMP_DEBUG_ASSERT(TCR_4(taskdata->td_allocated_child_tasks) == 0 || 629 taskdata->td_flags.task_serial == 1); 630 KMP_DEBUG_ASSERT(TCR_4(taskdata->td_incomplete_child_tasks) == 0); 631 632 taskdata->td_flags.freed = 1; 633 ANNOTATE_HAPPENS_BEFORE(taskdata); 634 // deallocate the taskdata and shared variable blocks associated with this task 635 #if USE_FAST_MEMORY 636 __kmp_fast_free(thread, taskdata); 637 #else /* ! USE_FAST_MEMORY */ 638 __kmp_thread_free(thread, taskdata); 639 #endif 640 641 KA_TRACE(20, ("__kmp_free_task: T#%d freed task %p\n", gtid, taskdata)); 642 } 643 644 // __kmp_free_task_and_ancestors: free the current task and ancestors without 645 // children 646 // 647 // gtid: Global thread ID of calling thread 648 // taskdata: task to free 649 // thread: thread data structure of caller 650 static void __kmp_free_task_and_ancestors(kmp_int32 gtid, 651 kmp_taskdata_t *taskdata, 652 kmp_info_t *thread) { 653 #if OMP_45_ENABLED 654 // Proxy tasks must always be allowed to free their parents 655 // because they can be run in background even in serial mode. 656 kmp_int32 team_serial = 657 (taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser) && 658 !taskdata->td_flags.proxy; 659 #else 660 kmp_int32 team_serial = 661 taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser; 662 #endif 663 KMP_DEBUG_ASSERT(taskdata->td_flags.tasktype == TASK_EXPLICIT); 664 665 kmp_int32 children = 666 KMP_TEST_THEN_DEC32(&taskdata->td_allocated_child_tasks) - 1; 667 KMP_DEBUG_ASSERT(children >= 0); 668 669 // Now, go up the ancestor tree to see if any ancestors can now be freed. 670 while (children == 0) { 671 kmp_taskdata_t *parent_taskdata = taskdata->td_parent; 672 673 KA_TRACE(20, ("__kmp_free_task_and_ancestors(enter): T#%d task %p complete " 674 "and freeing itself\n", 675 gtid, taskdata)); 676 677 // --- Deallocate my ancestor task --- 678 __kmp_free_task(gtid, taskdata, thread); 679 680 taskdata = parent_taskdata; 681 682 // Stop checking ancestors at implicit task instead of walking up ancestor 683 // tree to avoid premature deallocation of ancestors. 684 if (team_serial || taskdata->td_flags.tasktype == TASK_IMPLICIT) 685 return; 686 687 // Predecrement simulated by "- 1" calculation 688 children = KMP_TEST_THEN_DEC32(&taskdata->td_allocated_child_tasks) - 1; 689 KMP_DEBUG_ASSERT(children >= 0); 690 } 691 692 KA_TRACE( 693 20, ("__kmp_free_task_and_ancestors(exit): T#%d task %p has %d children; " 694 "not freeing it yet\n", 695 gtid, taskdata, children)); 696 } 697 698 // __kmp_task_finish: bookkeeping to do when a task finishes execution 699 // 700 // gtid: global thread ID for calling thread 701 // task: task to be finished 702 // resumed_task: task to be resumed. (may be NULL if task is serialized) 703 static void __kmp_task_finish(kmp_int32 gtid, kmp_task_t *task, 704 kmp_taskdata_t *resumed_task) { 705 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 706 kmp_info_t *thread = __kmp_threads[gtid]; 707 kmp_task_team_t *task_team = 708 thread->th.th_task_team; // might be NULL for serial teams... 709 kmp_int32 children = 0; 710 711 KA_TRACE(10, ("__kmp_task_finish(enter): T#%d finishing task %p and resuming " 712 "task %p\n", 713 gtid, taskdata, resumed_task)); 714 715 KMP_DEBUG_ASSERT(taskdata->td_flags.tasktype == TASK_EXPLICIT); 716 717 // Pop task from stack if tied 718 #ifdef BUILD_TIED_TASK_STACK 719 if (taskdata->td_flags.tiedness == TASK_TIED) { 720 __kmp_pop_task_stack(gtid, thread, taskdata); 721 } 722 #endif /* BUILD_TIED_TASK_STACK */ 723 724 if (taskdata->td_flags.tiedness == TASK_UNTIED) { 725 // untied task needs to check the counter so that the task structure is not 726 // freed prematurely 727 kmp_int32 counter = KMP_TEST_THEN_DEC32(&taskdata->td_untied_count) - 1; 728 KA_TRACE( 729 20, 730 ("__kmp_task_finish: T#%d untied_count (%d) decremented for task %p\n", 731 gtid, counter, taskdata)); 732 if (counter > 0) { 733 // untied task is not done, to be continued possibly by other thread, do 734 // not free it now 735 if (resumed_task == NULL) { 736 KMP_DEBUG_ASSERT(taskdata->td_flags.task_serial); 737 resumed_task = taskdata->td_parent; // In a serialized task, the resumed 738 // task is the parent 739 } 740 thread->th.th_current_task = resumed_task; // restore current_task 741 resumed_task->td_flags.executing = 1; // resume previous task 742 KA_TRACE(10, ("__kmp_task_finish(exit): T#%d partially done task %p, " 743 "resuming task %p\n", 744 gtid, taskdata, resumed_task)); 745 return; 746 } 747 } 748 749 KMP_DEBUG_ASSERT(taskdata->td_flags.complete == 0); 750 taskdata->td_flags.complete = 1; // mark the task as completed 751 KMP_DEBUG_ASSERT(taskdata->td_flags.started == 1); 752 KMP_DEBUG_ASSERT(taskdata->td_flags.freed == 0); 753 754 // Only need to keep track of count if team parallel and tasking not 755 // serialized 756 if (!(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser)) { 757 // Predecrement simulated by "- 1" calculation 758 children = 759 KMP_TEST_THEN_DEC32(&taskdata->td_parent->td_incomplete_child_tasks) - 760 1; 761 KMP_DEBUG_ASSERT(children >= 0); 762 #if OMP_40_ENABLED 763 if (taskdata->td_taskgroup) 764 KMP_TEST_THEN_DEC32((kmp_int32 *)(&taskdata->td_taskgroup->count)); 765 #if OMP_45_ENABLED 766 } 767 // if we found proxy tasks there could exist a dependency chain 768 // with the proxy task as origin 769 if (!(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser) || 770 (task_team && task_team->tt.tt_found_proxy_tasks)) { 771 #endif 772 __kmp_release_deps(gtid, taskdata); 773 #endif 774 } 775 776 // td_flags.executing must be marked as 0 after __kmp_release_deps has been 777 // called. Othertwise, if a task is executed immediately from the release_deps 778 // code, the flag will be reset to 1 again by this same function 779 KMP_DEBUG_ASSERT(taskdata->td_flags.executing == 1); 780 taskdata->td_flags.executing = 0; // suspend the finishing task 781 782 KA_TRACE( 783 20, ("__kmp_task_finish: T#%d finished task %p, %d incomplete children\n", 784 gtid, taskdata, children)); 785 786 #if OMP_40_ENABLED 787 /* If the tasks' destructor thunk flag has been set, we need to invoke the 788 destructor thunk that has been generated by the compiler. The code is 789 placed here, since at this point other tasks might have been released 790 hence overlapping the destructor invokations with some other work in the 791 released tasks. The OpenMP spec is not specific on when the destructors 792 are invoked, so we should be free to choose. */ 793 if (taskdata->td_flags.destructors_thunk) { 794 kmp_routine_entry_t destr_thunk = task->data1.destructors; 795 KMP_ASSERT(destr_thunk); 796 destr_thunk(gtid, task); 797 } 798 #endif // OMP_40_ENABLED 799 800 // bookkeeping for resuming task: 801 // GEH - note tasking_ser => task_serial 802 KMP_DEBUG_ASSERT( 803 (taskdata->td_flags.tasking_ser || taskdata->td_flags.task_serial) == 804 taskdata->td_flags.task_serial); 805 if (taskdata->td_flags.task_serial) { 806 if (resumed_task == NULL) { 807 resumed_task = taskdata->td_parent; // In a serialized task, the resumed 808 // task is the parent 809 } 810 } else { 811 KMP_DEBUG_ASSERT(resumed_task != 812 NULL); // verify that resumed task is passed as arguemnt 813 } 814 815 // Free this task and then ancestor tasks if they have no children. 816 // Restore th_current_task first as suggested by John: 817 // johnmc: if an asynchronous inquiry peers into the runtime system 818 // it doesn't see the freed task as the current task. 819 thread->th.th_current_task = resumed_task; 820 __kmp_free_task_and_ancestors(gtid, taskdata, thread); 821 822 // TODO: GEH - make sure root team implicit task is initialized properly. 823 // KMP_DEBUG_ASSERT( resumed_task->td_flags.executing == 0 ); 824 resumed_task->td_flags.executing = 1; // resume previous task 825 826 KA_TRACE( 827 10, ("__kmp_task_finish(exit): T#%d finished task %p, resuming task %p\n", 828 gtid, taskdata, resumed_task)); 829 830 return; 831 } 832 833 template <bool ompt> 834 static void __kmpc_omp_task_complete_if0_template(ident_t *loc_ref, 835 kmp_int32 gtid, 836 kmp_task_t *task) { 837 KA_TRACE(10, ("__kmpc_omp_task_complete_if0(enter): T#%d loc=%p task=%p\n", 838 gtid, loc_ref, KMP_TASK_TO_TASKDATA(task))); 839 // this routine will provide task to resume 840 __kmp_task_finish(gtid, task, NULL); 841 842 KA_TRACE(10, ("__kmpc_omp_task_complete_if0(exit): T#%d loc=%p task=%p\n", 843 gtid, loc_ref, KMP_TASK_TO_TASKDATA(task))); 844 845 #if OMPT_SUPPORT 846 if (ompt) { 847 __ompt_task_finish(task, NULL); 848 ompt_frame_t *ompt_frame; 849 __ompt_get_task_info_internal(0, NULL, NULL, &ompt_frame, NULL, NULL); 850 ompt_frame->enter_frame = NULL; 851 } 852 #endif 853 854 return; 855 } 856 857 #if OMPT_SUPPORT 858 OMPT_NOINLINE 859 void __kmpc_omp_task_complete_if0_ompt(ident_t *loc_ref, kmp_int32 gtid, 860 kmp_task_t *task) { 861 __kmpc_omp_task_complete_if0_template<true>(loc_ref, gtid, task); 862 } 863 #endif // OMPT_SUPPORT 864 865 // __kmpc_omp_task_complete_if0: report that a task has completed execution 866 // 867 // loc_ref: source location information; points to end of task block. 868 // gtid: global thread number. 869 // task: task thunk for the completed task. 870 void __kmpc_omp_task_complete_if0(ident_t *loc_ref, kmp_int32 gtid, 871 kmp_task_t *task) { 872 #if OMPT_SUPPORT 873 if (UNLIKELY(ompt_enabled.enabled)) { 874 __kmpc_omp_task_complete_if0_ompt(loc_ref, gtid, task); 875 return; 876 } 877 #endif 878 __kmpc_omp_task_complete_if0_template<false>(loc_ref, gtid, task); 879 } 880 881 #ifdef TASK_UNUSED 882 // __kmpc_omp_task_complete: report that a task has completed execution 883 // NEVER GENERATED BY COMPILER, DEPRECATED!!! 884 void __kmpc_omp_task_complete(ident_t *loc_ref, kmp_int32 gtid, 885 kmp_task_t *task) { 886 KA_TRACE(10, ("__kmpc_omp_task_complete(enter): T#%d loc=%p task=%p\n", gtid, 887 loc_ref, KMP_TASK_TO_TASKDATA(task))); 888 889 __kmp_task_finish(gtid, task, NULL); // Not sure how to find task to resume 890 891 KA_TRACE(10, ("__kmpc_omp_task_complete(exit): T#%d loc=%p task=%p\n", gtid, 892 loc_ref, KMP_TASK_TO_TASKDATA(task))); 893 return; 894 } 895 #endif // TASK_UNUSED 896 897 // __kmp_init_implicit_task: Initialize the appropriate fields in the implicit 898 // task for a given thread 899 // 900 // loc_ref: reference to source location of parallel region 901 // this_thr: thread data structure corresponding to implicit task 902 // team: team for this_thr 903 // tid: thread id of given thread within team 904 // set_curr_task: TRUE if need to push current task to thread 905 // NOTE: Routine does not set up the implicit task ICVS. This is assumed to 906 // have already been done elsewhere. 907 // TODO: Get better loc_ref. Value passed in may be NULL 908 void __kmp_init_implicit_task(ident_t *loc_ref, kmp_info_t *this_thr, 909 kmp_team_t *team, int tid, int set_curr_task) { 910 kmp_taskdata_t *task = &team->t.t_implicit_task_taskdata[tid]; 911 912 KF_TRACE( 913 10, 914 ("__kmp_init_implicit_task(enter): T#:%d team=%p task=%p, reinit=%s\n", 915 tid, team, task, set_curr_task ? "TRUE" : "FALSE")); 916 917 task->td_task_id = KMP_GEN_TASK_ID(); 918 task->td_team = team; 919 // task->td_parent = NULL; // fix for CQ230101 (broken parent task info 920 // in debugger) 921 task->td_ident = loc_ref; 922 task->td_taskwait_ident = NULL; 923 task->td_taskwait_counter = 0; 924 task->td_taskwait_thread = 0; 925 926 task->td_flags.tiedness = TASK_TIED; 927 task->td_flags.tasktype = TASK_IMPLICIT; 928 #if OMP_45_ENABLED 929 task->td_flags.proxy = TASK_FULL; 930 #endif 931 932 // All implicit tasks are executed immediately, not deferred 933 task->td_flags.task_serial = 1; 934 task->td_flags.tasking_ser = (__kmp_tasking_mode == tskm_immediate_exec); 935 task->td_flags.team_serial = (team->t.t_serialized) ? 1 : 0; 936 937 task->td_flags.started = 1; 938 task->td_flags.executing = 1; 939 task->td_flags.complete = 0; 940 task->td_flags.freed = 0; 941 942 #if OMP_40_ENABLED 943 task->td_depnode = NULL; 944 #endif 945 task->td_last_tied = task; 946 947 if (set_curr_task) { // only do this init first time thread is created 948 task->td_incomplete_child_tasks = 0; 949 // Not used: don't need to deallocate implicit task 950 task->td_allocated_child_tasks = 0; 951 #if OMP_40_ENABLED 952 task->td_taskgroup = NULL; // An implicit task does not have taskgroup 953 task->td_dephash = NULL; 954 #endif 955 __kmp_push_current_task_to_thread(this_thr, team, tid); 956 } else { 957 KMP_DEBUG_ASSERT(task->td_incomplete_child_tasks == 0); 958 KMP_DEBUG_ASSERT(task->td_allocated_child_tasks == 0); 959 } 960 961 #if OMPT_SUPPORT 962 if (UNLIKELY(ompt_enabled.enabled)) 963 __ompt_task_init(task, tid); 964 #endif 965 966 KF_TRACE(10, ("__kmp_init_implicit_task(exit): T#:%d team=%p task=%p\n", tid, 967 team, task)); 968 } 969 970 // __kmp_finish_implicit_task: Release resources associated to implicit tasks 971 // at the end of parallel regions. Some resources are kept for reuse in the next 972 // parallel region. 973 // 974 // thread: thread data structure corresponding to implicit task 975 void __kmp_finish_implicit_task(kmp_info_t *thread) { 976 kmp_taskdata_t *task = thread->th.th_current_task; 977 if (task->td_dephash) 978 __kmp_dephash_free_entries(thread, task->td_dephash); 979 } 980 981 // __kmp_free_implicit_task: Release resources associated to implicit tasks 982 // when these are destroyed regions 983 // 984 // thread: thread data structure corresponding to implicit task 985 void __kmp_free_implicit_task(kmp_info_t *thread) { 986 kmp_taskdata_t *task = thread->th.th_current_task; 987 if (task && task->td_dephash) { 988 __kmp_dephash_free(thread, task->td_dephash); 989 task->td_dephash = NULL; 990 } 991 } 992 993 // Round up a size to a power of two specified by val: Used to insert padding 994 // between structures co-allocated using a single malloc() call 995 static size_t __kmp_round_up_to_val(size_t size, size_t val) { 996 if (size & (val - 1)) { 997 size &= ~(val - 1); 998 if (size <= KMP_SIZE_T_MAX - val) { 999 size += val; // Round up if there is no overflow. 1000 } 1001 } 1002 return size; 1003 } // __kmp_round_up_to_va 1004 1005 // __kmp_task_alloc: Allocate the taskdata and task data structures for a task 1006 // 1007 // loc_ref: source location information 1008 // gtid: global thread number. 1009 // flags: include tiedness & task type (explicit vs. implicit) of the ''new'' 1010 // task encountered. Converted from kmp_int32 to kmp_tasking_flags_t in routine. 1011 // sizeof_kmp_task_t: Size in bytes of kmp_task_t data structure including 1012 // private vars accessed in task. 1013 // sizeof_shareds: Size in bytes of array of pointers to shared vars accessed 1014 // in task. 1015 // task_entry: Pointer to task code entry point generated by compiler. 1016 // returns: a pointer to the allocated kmp_task_t structure (task). 1017 kmp_task_t *__kmp_task_alloc(ident_t *loc_ref, kmp_int32 gtid, 1018 kmp_tasking_flags_t *flags, 1019 size_t sizeof_kmp_task_t, size_t sizeof_shareds, 1020 kmp_routine_entry_t task_entry) { 1021 kmp_task_t *task; 1022 kmp_taskdata_t *taskdata; 1023 kmp_info_t *thread = __kmp_threads[gtid]; 1024 kmp_team_t *team = thread->th.th_team; 1025 kmp_taskdata_t *parent_task = thread->th.th_current_task; 1026 size_t shareds_offset; 1027 1028 KA_TRACE(10, ("__kmp_task_alloc(enter): T#%d loc=%p, flags=(0x%x) " 1029 "sizeof_task=%ld sizeof_shared=%ld entry=%p\n", 1030 gtid, loc_ref, *((kmp_int32 *)flags), sizeof_kmp_task_t, 1031 sizeof_shareds, task_entry)); 1032 1033 if (parent_task->td_flags.final) { 1034 if (flags->merged_if0) { 1035 } 1036 flags->final = 1; 1037 } 1038 if (flags->tiedness == TASK_UNTIED && !team->t.t_serialized) { 1039 // Untied task encountered causes the TSC algorithm to check entire deque of 1040 // the victim thread. If no untied task encountered, then checking the head 1041 // of the deque should be enough. 1042 KMP_CHECK_UPDATE(thread->th.th_task_team->tt.tt_untied_task_encountered, 1); 1043 } 1044 1045 #if OMP_45_ENABLED 1046 if (flags->proxy == TASK_PROXY) { 1047 flags->tiedness = TASK_UNTIED; 1048 flags->merged_if0 = 1; 1049 1050 /* are we running in a sequential parallel or tskm_immediate_exec... we need 1051 tasking support enabled */ 1052 if ((thread->th.th_task_team) == NULL) { 1053 /* This should only happen if the team is serialized 1054 setup a task team and propagate it to the thread */ 1055 KMP_DEBUG_ASSERT(team->t.t_serialized); 1056 KA_TRACE(30, 1057 ("T#%d creating task team in __kmp_task_alloc for proxy task\n", 1058 gtid)); 1059 __kmp_task_team_setup( 1060 thread, team, 1061 1); // 1 indicates setup the current team regardless of nthreads 1062 thread->th.th_task_team = team->t.t_task_team[thread->th.th_task_state]; 1063 } 1064 kmp_task_team_t *task_team = thread->th.th_task_team; 1065 1066 /* tasking must be enabled now as the task might not be pushed */ 1067 if (!KMP_TASKING_ENABLED(task_team)) { 1068 KA_TRACE( 1069 30, 1070 ("T#%d enabling tasking in __kmp_task_alloc for proxy task\n", gtid)); 1071 __kmp_enable_tasking(task_team, thread); 1072 kmp_int32 tid = thread->th.th_info.ds.ds_tid; 1073 kmp_thread_data_t *thread_data = &task_team->tt.tt_threads_data[tid]; 1074 // No lock needed since only owner can allocate 1075 if (thread_data->td.td_deque == NULL) { 1076 __kmp_alloc_task_deque(thread, thread_data); 1077 } 1078 } 1079 1080 if (task_team->tt.tt_found_proxy_tasks == FALSE) 1081 TCW_4(task_team->tt.tt_found_proxy_tasks, TRUE); 1082 } 1083 #endif 1084 1085 // Calculate shared structure offset including padding after kmp_task_t struct 1086 // to align pointers in shared struct 1087 shareds_offset = sizeof(kmp_taskdata_t) + sizeof_kmp_task_t; 1088 shareds_offset = __kmp_round_up_to_val(shareds_offset, sizeof(void *)); 1089 1090 // Allocate a kmp_taskdata_t block and a kmp_task_t block. 1091 KA_TRACE(30, ("__kmp_task_alloc: T#%d First malloc size: %ld\n", gtid, 1092 shareds_offset)); 1093 KA_TRACE(30, ("__kmp_task_alloc: T#%d Second malloc size: %ld\n", gtid, 1094 sizeof_shareds)); 1095 1096 // Avoid double allocation here by combining shareds with taskdata 1097 #if USE_FAST_MEMORY 1098 taskdata = (kmp_taskdata_t *)__kmp_fast_allocate(thread, shareds_offset + 1099 sizeof_shareds); 1100 #else /* ! USE_FAST_MEMORY */ 1101 taskdata = (kmp_taskdata_t *)__kmp_thread_malloc(thread, shareds_offset + 1102 sizeof_shareds); 1103 #endif /* USE_FAST_MEMORY */ 1104 ANNOTATE_HAPPENS_AFTER(taskdata); 1105 1106 task = KMP_TASKDATA_TO_TASK(taskdata); 1107 1108 // Make sure task & taskdata are aligned appropriately 1109 #if KMP_ARCH_X86 || KMP_ARCH_PPC64 || !KMP_HAVE_QUAD 1110 KMP_DEBUG_ASSERT((((kmp_uintptr_t)taskdata) & (sizeof(double) - 1)) == 0); 1111 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task) & (sizeof(double) - 1)) == 0); 1112 #else 1113 KMP_DEBUG_ASSERT((((kmp_uintptr_t)taskdata) & (sizeof(_Quad) - 1)) == 0); 1114 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task) & (sizeof(_Quad) - 1)) == 0); 1115 #endif 1116 if (sizeof_shareds > 0) { 1117 // Avoid double allocation here by combining shareds with taskdata 1118 task->shareds = &((char *)taskdata)[shareds_offset]; 1119 // Make sure shareds struct is aligned to pointer size 1120 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task->shareds) & (sizeof(void *) - 1)) == 1121 0); 1122 } else { 1123 task->shareds = NULL; 1124 } 1125 task->routine = task_entry; 1126 task->part_id = 0; // AC: Always start with 0 part id 1127 1128 taskdata->td_task_id = KMP_GEN_TASK_ID(); 1129 taskdata->td_team = team; 1130 taskdata->td_alloc_thread = thread; 1131 taskdata->td_parent = parent_task; 1132 taskdata->td_level = parent_task->td_level + 1; // increment nesting level 1133 taskdata->td_untied_count = 0; 1134 taskdata->td_ident = loc_ref; 1135 taskdata->td_taskwait_ident = NULL; 1136 taskdata->td_taskwait_counter = 0; 1137 taskdata->td_taskwait_thread = 0; 1138 KMP_DEBUG_ASSERT(taskdata->td_parent != NULL); 1139 #if OMP_45_ENABLED 1140 // avoid copying icvs for proxy tasks 1141 if (flags->proxy == TASK_FULL) 1142 #endif 1143 copy_icvs(&taskdata->td_icvs, &taskdata->td_parent->td_icvs); 1144 1145 taskdata->td_flags.tiedness = flags->tiedness; 1146 taskdata->td_flags.final = flags->final; 1147 taskdata->td_flags.merged_if0 = flags->merged_if0; 1148 #if OMP_40_ENABLED 1149 taskdata->td_flags.destructors_thunk = flags->destructors_thunk; 1150 #endif // OMP_40_ENABLED 1151 #if OMP_45_ENABLED 1152 taskdata->td_flags.proxy = flags->proxy; 1153 taskdata->td_task_team = thread->th.th_task_team; 1154 taskdata->td_size_alloc = shareds_offset + sizeof_shareds; 1155 #endif 1156 taskdata->td_flags.tasktype = TASK_EXPLICIT; 1157 1158 // GEH - TODO: fix this to copy parent task's value of tasking_ser flag 1159 taskdata->td_flags.tasking_ser = (__kmp_tasking_mode == tskm_immediate_exec); 1160 1161 // GEH - TODO: fix this to copy parent task's value of team_serial flag 1162 taskdata->td_flags.team_serial = (team->t.t_serialized) ? 1 : 0; 1163 1164 // GEH - Note we serialize the task if the team is serialized to make sure 1165 // implicit parallel region tasks are not left until program termination to 1166 // execute. Also, it helps locality to execute immediately. 1167 1168 taskdata->td_flags.task_serial = 1169 (parent_task->td_flags.final || taskdata->td_flags.team_serial || 1170 taskdata->td_flags.tasking_ser); 1171 1172 taskdata->td_flags.started = 0; 1173 taskdata->td_flags.executing = 0; 1174 taskdata->td_flags.complete = 0; 1175 taskdata->td_flags.freed = 0; 1176 1177 taskdata->td_flags.native = flags->native; 1178 1179 taskdata->td_incomplete_child_tasks = 0; 1180 taskdata->td_allocated_child_tasks = 1; // start at one because counts current 1181 // task and children 1182 #if OMP_40_ENABLED 1183 taskdata->td_taskgroup = 1184 parent_task->td_taskgroup; // task inherits taskgroup from the parent task 1185 taskdata->td_dephash = NULL; 1186 taskdata->td_depnode = NULL; 1187 #endif 1188 if (flags->tiedness == TASK_UNTIED) 1189 taskdata->td_last_tied = NULL; // will be set when the task is scheduled 1190 else 1191 taskdata->td_last_tied = taskdata; 1192 1193 // Only need to keep track of child task counts if team parallel and tasking not 1194 // serialized or if it is a proxy task 1195 #if OMP_45_ENABLED 1196 if (flags->proxy == TASK_PROXY || 1197 !(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser)) 1198 #else 1199 if (!(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser)) 1200 #endif 1201 { 1202 KMP_TEST_THEN_INC32(&parent_task->td_incomplete_child_tasks); 1203 #if OMP_40_ENABLED 1204 if (parent_task->td_taskgroup) 1205 KMP_TEST_THEN_INC32((kmp_int32 *)(&parent_task->td_taskgroup->count)); 1206 #endif 1207 // Only need to keep track of allocated child tasks for explicit tasks since 1208 // implicit not deallocated 1209 if (taskdata->td_parent->td_flags.tasktype == TASK_EXPLICIT) { 1210 KMP_TEST_THEN_INC32(&taskdata->td_parent->td_allocated_child_tasks); 1211 } 1212 } 1213 1214 KA_TRACE(20, ("__kmp_task_alloc(exit): T#%d created task %p parent=%p\n", 1215 gtid, taskdata, taskdata->td_parent)); 1216 ANNOTATE_HAPPENS_BEFORE(task); 1217 1218 #if OMPT_SUPPORT 1219 if (UNLIKELY(ompt_enabled.enabled)) 1220 __ompt_task_init(taskdata, gtid); 1221 #endif 1222 1223 return task; 1224 } 1225 1226 kmp_task_t *__kmpc_omp_task_alloc(ident_t *loc_ref, kmp_int32 gtid, 1227 kmp_int32 flags, size_t sizeof_kmp_task_t, 1228 size_t sizeof_shareds, 1229 kmp_routine_entry_t task_entry) { 1230 kmp_task_t *retval; 1231 kmp_tasking_flags_t *input_flags = (kmp_tasking_flags_t *)&flags; 1232 1233 input_flags->native = FALSE; 1234 // __kmp_task_alloc() sets up all other runtime flags 1235 1236 #if OMP_45_ENABLED 1237 KA_TRACE(10, ("__kmpc_omp_task_alloc(enter): T#%d loc=%p, flags=(%s %s) " 1238 "sizeof_task=%ld sizeof_shared=%ld entry=%p\n", 1239 gtid, loc_ref, input_flags->tiedness ? "tied " : "untied", 1240 input_flags->proxy ? "proxy" : "", sizeof_kmp_task_t, 1241 sizeof_shareds, task_entry)); 1242 #else 1243 KA_TRACE(10, ("__kmpc_omp_task_alloc(enter): T#%d loc=%p, flags=(%s) " 1244 "sizeof_task=%ld sizeof_shared=%ld entry=%p\n", 1245 gtid, loc_ref, input_flags->tiedness ? "tied " : "untied", 1246 sizeof_kmp_task_t, sizeof_shareds, task_entry)); 1247 #endif 1248 1249 retval = __kmp_task_alloc(loc_ref, gtid, input_flags, sizeof_kmp_task_t, 1250 sizeof_shareds, task_entry); 1251 1252 KA_TRACE(20, ("__kmpc_omp_task_alloc(exit): T#%d retval %p\n", gtid, retval)); 1253 1254 return retval; 1255 } 1256 1257 // __kmp_invoke_task: invoke the specified task 1258 // 1259 // gtid: global thread ID of caller 1260 // task: the task to invoke 1261 // current_task: the task to resume after task invokation 1262 static void __kmp_invoke_task(kmp_int32 gtid, kmp_task_t *task, 1263 kmp_taskdata_t *current_task) { 1264 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 1265 kmp_uint64 cur_time; 1266 #if OMP_40_ENABLED 1267 int discard = 0 /* false */; 1268 #endif 1269 KA_TRACE( 1270 30, ("__kmp_invoke_task(enter): T#%d invoking task %p, current_task=%p\n", 1271 gtid, taskdata, current_task)); 1272 KMP_DEBUG_ASSERT(task); 1273 #if OMP_45_ENABLED 1274 if (taskdata->td_flags.proxy == TASK_PROXY && 1275 taskdata->td_flags.complete == 1) { 1276 // This is a proxy task that was already completed but it needs to run 1277 // its bottom-half finish 1278 KA_TRACE( 1279 30, 1280 ("__kmp_invoke_task: T#%d running bottom finish for proxy task %p\n", 1281 gtid, taskdata)); 1282 1283 __kmp_bottom_half_finish_proxy(gtid, task); 1284 1285 KA_TRACE(30, ("__kmp_invoke_task(exit): T#%d completed bottom finish for " 1286 "proxy task %p, resuming task %p\n", 1287 gtid, taskdata, current_task)); 1288 1289 return; 1290 } 1291 #endif 1292 1293 #if USE_ITT_BUILD && USE_ITT_NOTIFY 1294 if (__kmp_forkjoin_frames_mode == 3) { 1295 // Get the current time stamp to measure task execution time to correct 1296 // barrier imbalance time 1297 cur_time = __itt_get_timestamp(); 1298 } 1299 #endif 1300 1301 #if OMP_45_ENABLED 1302 // Proxy tasks are not handled by the runtime 1303 if (taskdata->td_flags.proxy != TASK_PROXY) { 1304 #endif 1305 ANNOTATE_HAPPENS_AFTER(task); 1306 __kmp_task_start(gtid, task, current_task); // OMPT only if not discarded 1307 #if OMP_45_ENABLED 1308 } 1309 #endif 1310 1311 #if OMPT_SUPPORT 1312 ompt_thread_info_t oldInfo; 1313 kmp_info_t *thread; 1314 if (UNLIKELY(ompt_enabled.enabled)) { 1315 // Store the threads states and restore them after the task 1316 thread = __kmp_threads[gtid]; 1317 oldInfo = thread->th.ompt_thread_info; 1318 thread->th.ompt_thread_info.wait_id = 0; 1319 thread->th.ompt_thread_info.state = (thread->th.th_team_serialized) 1320 ? omp_state_work_serial 1321 : omp_state_work_parallel; 1322 taskdata->ompt_task_info.frame.exit_frame = OMPT_GET_FRAME_ADDRESS(0); 1323 } 1324 #endif 1325 1326 #if OMP_40_ENABLED 1327 // TODO: cancel tasks if the parallel region has also been cancelled 1328 // TODO: check if this sequence can be hoisted above __kmp_task_start 1329 // if cancellation has been enabled for this run ... 1330 if (__kmp_omp_cancellation) { 1331 kmp_info_t *this_thr = __kmp_threads[gtid]; 1332 kmp_team_t *this_team = this_thr->th.th_team; 1333 kmp_taskgroup_t *taskgroup = taskdata->td_taskgroup; 1334 if ((taskgroup && taskgroup->cancel_request) || 1335 (this_team->t.t_cancel_request == cancel_parallel)) { 1336 #if OMPT_SUPPORT && OMPT_OPTIONAL 1337 ompt_data_t *task_data; 1338 if (UNLIKELY(ompt_enabled.ompt_callback_cancel)) { 1339 __ompt_get_task_info_internal(0, NULL, &task_data, NULL, NULL, NULL); 1340 ompt_callbacks.ompt_callback(ompt_callback_cancel)( 1341 task_data, 1342 ((taskgroup && taskgroup->cancel_request) ? ompt_cancel_taskgroup 1343 : ompt_cancel_parallel) | 1344 ompt_cancel_discarded_task, 1345 NULL); 1346 } 1347 #endif 1348 KMP_COUNT_BLOCK(TASK_cancelled); 1349 // this task belongs to a task group and we need to cancel it 1350 discard = 1 /* true */; 1351 } 1352 } 1353 1354 // Invoke the task routine and pass in relevant data. 1355 // Thunks generated by gcc take a different argument list. 1356 if (!discard) { 1357 if (taskdata->td_flags.tiedness == TASK_UNTIED) { 1358 taskdata->td_last_tied = current_task->td_last_tied; 1359 KMP_DEBUG_ASSERT(taskdata->td_last_tied); 1360 } 1361 #if KMP_STATS_ENABLED 1362 KMP_COUNT_BLOCK(TASK_executed); 1363 switch (KMP_GET_THREAD_STATE()) { 1364 case FORK_JOIN_BARRIER: 1365 KMP_PUSH_PARTITIONED_TIMER(OMP_task_join_bar); 1366 break; 1367 case PLAIN_BARRIER: 1368 KMP_PUSH_PARTITIONED_TIMER(OMP_task_plain_bar); 1369 break; 1370 case TASKYIELD: 1371 KMP_PUSH_PARTITIONED_TIMER(OMP_task_taskyield); 1372 break; 1373 case TASKWAIT: 1374 KMP_PUSH_PARTITIONED_TIMER(OMP_task_taskwait); 1375 break; 1376 case TASKGROUP: 1377 KMP_PUSH_PARTITIONED_TIMER(OMP_task_taskgroup); 1378 break; 1379 default: 1380 KMP_PUSH_PARTITIONED_TIMER(OMP_task_immediate); 1381 break; 1382 } 1383 #endif // KMP_STATS_ENABLED 1384 #endif // OMP_40_ENABLED 1385 1386 // OMPT task begin 1387 #if OMPT_SUPPORT 1388 if (UNLIKELY(ompt_enabled.enabled)) 1389 __ompt_task_start(task, current_task, gtid); 1390 #endif 1391 1392 #ifdef KMP_GOMP_COMPAT 1393 if (taskdata->td_flags.native) { 1394 ((void (*)(void *))(*(task->routine)))(task->shareds); 1395 } else 1396 #endif /* KMP_GOMP_COMPAT */ 1397 { 1398 (*(task->routine))(gtid, task); 1399 } 1400 KMP_POP_PARTITIONED_TIMER(); 1401 1402 #if OMPT_SUPPORT 1403 if (UNLIKELY(ompt_enabled.enabled)) 1404 __ompt_task_finish(task, current_task); 1405 #endif 1406 #if OMP_40_ENABLED 1407 } 1408 #endif // OMP_40_ENABLED 1409 1410 #if OMPT_SUPPORT 1411 if (UNLIKELY(ompt_enabled.enabled)) { 1412 thread->th.ompt_thread_info = oldInfo; 1413 taskdata->ompt_task_info.frame.exit_frame = NULL; 1414 } 1415 #endif 1416 1417 #if OMP_45_ENABLED 1418 // Proxy tasks are not handled by the runtime 1419 if (taskdata->td_flags.proxy != TASK_PROXY) { 1420 #endif 1421 ANNOTATE_HAPPENS_BEFORE(taskdata->td_parent); 1422 __kmp_task_finish(gtid, task, current_task); // OMPT only if not discarded 1423 #if OMP_45_ENABLED 1424 } 1425 #endif 1426 1427 #if USE_ITT_BUILD && USE_ITT_NOTIFY 1428 // Barrier imbalance - correct arrive time after the task finished 1429 if (__kmp_forkjoin_frames_mode == 3) { 1430 kmp_info_t *this_thr = __kmp_threads[gtid]; 1431 if (this_thr->th.th_bar_arrive_time) { 1432 this_thr->th.th_bar_arrive_time += (__itt_get_timestamp() - cur_time); 1433 } 1434 } 1435 #endif 1436 KA_TRACE( 1437 30, 1438 ("__kmp_invoke_task(exit): T#%d completed task %p, resuming task %p\n", 1439 gtid, taskdata, current_task)); 1440 return; 1441 } 1442 1443 // __kmpc_omp_task_parts: Schedule a thread-switchable task for execution 1444 // 1445 // loc_ref: location of original task pragma (ignored) 1446 // gtid: Global Thread ID of encountering thread 1447 // new_task: task thunk allocated by __kmp_omp_task_alloc() for the ''new task'' 1448 // Returns: 1449 // TASK_CURRENT_NOT_QUEUED (0) if did not suspend and queue current task to 1450 // be resumed later. 1451 // TASK_CURRENT_QUEUED (1) if suspended and queued the current task to be 1452 // resumed later. 1453 kmp_int32 __kmpc_omp_task_parts(ident_t *loc_ref, kmp_int32 gtid, 1454 kmp_task_t *new_task) { 1455 kmp_taskdata_t *new_taskdata = KMP_TASK_TO_TASKDATA(new_task); 1456 1457 KA_TRACE(10, ("__kmpc_omp_task_parts(enter): T#%d loc=%p task=%p\n", gtid, 1458 loc_ref, new_taskdata)); 1459 1460 #if OMPT_SUPPORT 1461 kmp_taskdata_t *parent; 1462 if (UNLIKELY(ompt_enabled.enabled)) { 1463 parent = new_taskdata->td_parent; 1464 if (ompt_enabled.ompt_callback_task_create) { 1465 ompt_data_t task_data = ompt_data_none; 1466 ompt_callbacks.ompt_callback(ompt_callback_task_create)( 1467 parent ? &(parent->ompt_task_info.task_data) : &task_data, 1468 parent ? &(parent->ompt_task_info.frame) : NULL, 1469 &(new_taskdata->ompt_task_info.task_data), ompt_task_explicit, 0, 1470 OMPT_GET_RETURN_ADDRESS(0)); 1471 } 1472 } 1473 #endif 1474 1475 /* Should we execute the new task or queue it? For now, let's just always try 1476 to queue it. If the queue fills up, then we'll execute it. */ 1477 1478 if (__kmp_push_task(gtid, new_task) == TASK_NOT_PUSHED) // if cannot defer 1479 { // Execute this task immediately 1480 kmp_taskdata_t *current_task = __kmp_threads[gtid]->th.th_current_task; 1481 new_taskdata->td_flags.task_serial = 1; 1482 __kmp_invoke_task(gtid, new_task, current_task); 1483 } 1484 1485 KA_TRACE( 1486 10, 1487 ("__kmpc_omp_task_parts(exit): T#%d returning TASK_CURRENT_NOT_QUEUED: " 1488 "loc=%p task=%p, return: TASK_CURRENT_NOT_QUEUED\n", 1489 gtid, loc_ref, new_taskdata)); 1490 1491 ANNOTATE_HAPPENS_BEFORE(new_task); 1492 #if OMPT_SUPPORT 1493 if (UNLIKELY(ompt_enabled.enabled)) { 1494 parent->ompt_task_info.frame.enter_frame = NULL; 1495 } 1496 #endif 1497 return TASK_CURRENT_NOT_QUEUED; 1498 } 1499 1500 // __kmp_omp_task: Schedule a non-thread-switchable task for execution 1501 // 1502 // gtid: Global Thread ID of encountering thread 1503 // new_task:non-thread-switchable task thunk allocated by __kmp_omp_task_alloc() 1504 // serialize_immediate: if TRUE then if the task is executed immediately its 1505 // execution will be serialized 1506 // Returns: 1507 // TASK_CURRENT_NOT_QUEUED (0) if did not suspend and queue current task to 1508 // be resumed later. 1509 // TASK_CURRENT_QUEUED (1) if suspended and queued the current task to be 1510 // resumed later. 1511 kmp_int32 __kmp_omp_task(kmp_int32 gtid, kmp_task_t *new_task, 1512 bool serialize_immediate) { 1513 kmp_taskdata_t *new_taskdata = KMP_TASK_TO_TASKDATA(new_task); 1514 1515 /* Should we execute the new task or queue it? For now, let's just always try to 1516 queue it. If the queue fills up, then we'll execute it. */ 1517 #if OMP_45_ENABLED 1518 if (new_taskdata->td_flags.proxy == TASK_PROXY || 1519 __kmp_push_task(gtid, new_task) == TASK_NOT_PUSHED) // if cannot defer 1520 #else 1521 if (__kmp_push_task(gtid, new_task) == TASK_NOT_PUSHED) // if cannot defer 1522 #endif 1523 { // Execute this task immediately 1524 kmp_taskdata_t *current_task = __kmp_threads[gtid]->th.th_current_task; 1525 if (serialize_immediate) 1526 new_taskdata->td_flags.task_serial = 1; 1527 __kmp_invoke_task(gtid, new_task, current_task); 1528 } 1529 1530 ANNOTATE_HAPPENS_BEFORE(new_task); 1531 return TASK_CURRENT_NOT_QUEUED; 1532 } 1533 1534 // __kmpc_omp_task: Wrapper around __kmp_omp_task to schedule a 1535 // non-thread-switchable task from the parent thread only! 1536 // 1537 // loc_ref: location of original task pragma (ignored) 1538 // gtid: Global Thread ID of encountering thread 1539 // new_task: non-thread-switchable task thunk allocated by 1540 // __kmp_omp_task_alloc() 1541 // Returns: 1542 // TASK_CURRENT_NOT_QUEUED (0) if did not suspend and queue current task to 1543 // be resumed later. 1544 // TASK_CURRENT_QUEUED (1) if suspended and queued the current task to be 1545 // resumed later. 1546 kmp_int32 __kmpc_omp_task(ident_t *loc_ref, kmp_int32 gtid, 1547 kmp_task_t *new_task) { 1548 kmp_int32 res; 1549 KMP_SET_THREAD_STATE_BLOCK(EXPLICIT_TASK); 1550 1551 #if KMP_DEBUG || OMPT_SUPPORT 1552 kmp_taskdata_t *new_taskdata = KMP_TASK_TO_TASKDATA(new_task); 1553 #endif 1554 KA_TRACE(10, ("__kmpc_omp_task(enter): T#%d loc=%p task=%p\n", gtid, loc_ref, 1555 new_taskdata)); 1556 1557 #if OMPT_SUPPORT 1558 kmp_taskdata_t *parent = NULL; 1559 if (UNLIKELY(ompt_enabled.enabled && !new_taskdata->td_flags.started)) { 1560 OMPT_STORE_RETURN_ADDRESS(gtid); 1561 parent = new_taskdata->td_parent; 1562 if (!parent->ompt_task_info.frame.enter_frame) 1563 parent->ompt_task_info.frame.enter_frame = OMPT_GET_FRAME_ADDRESS(1); 1564 if (ompt_enabled.ompt_callback_task_create) { 1565 ompt_data_t task_data = ompt_data_none; 1566 ompt_callbacks.ompt_callback(ompt_callback_task_create)( 1567 parent ? &(parent->ompt_task_info.task_data) : &task_data, 1568 parent ? &(parent->ompt_task_info.frame) : NULL, 1569 &(new_taskdata->ompt_task_info.task_data), 1570 ompt_task_explicit | TASK_TYPE_DETAILS_FORMAT(new_taskdata), 0, 1571 OMPT_LOAD_RETURN_ADDRESS(gtid)); 1572 } 1573 } 1574 #endif 1575 1576 res = __kmp_omp_task(gtid, new_task, true); 1577 1578 KA_TRACE(10, ("__kmpc_omp_task(exit): T#%d returning " 1579 "TASK_CURRENT_NOT_QUEUED: loc=%p task=%p\n", 1580 gtid, loc_ref, new_taskdata)); 1581 #if OMPT_SUPPORT 1582 if (UNLIKELY(ompt_enabled.enabled && parent != NULL)) { 1583 parent->ompt_task_info.frame.enter_frame = NULL; 1584 } 1585 #endif 1586 return res; 1587 } 1588 1589 template <bool ompt> 1590 static kmp_int32 __kmpc_omp_taskwait_template(ident_t *loc_ref, kmp_int32 gtid, 1591 void *frame_address, 1592 void *return_address) { 1593 kmp_taskdata_t *taskdata; 1594 kmp_info_t *thread; 1595 int thread_finished = FALSE; 1596 KMP_SET_THREAD_STATE_BLOCK(TASKWAIT); 1597 1598 KA_TRACE(10, ("__kmpc_omp_taskwait(enter): T#%d loc=%p\n", gtid, loc_ref)); 1599 1600 if (__kmp_tasking_mode != tskm_immediate_exec) { 1601 thread = __kmp_threads[gtid]; 1602 taskdata = thread->th.th_current_task; 1603 1604 #if OMPT_SUPPORT && OMPT_OPTIONAL 1605 ompt_data_t *my_task_data; 1606 ompt_data_t *my_parallel_data; 1607 1608 if (ompt) { 1609 my_task_data = &(taskdata->ompt_task_info.task_data); 1610 my_parallel_data = OMPT_CUR_TEAM_DATA(thread); 1611 1612 taskdata->ompt_task_info.frame.enter_frame = frame_address; 1613 1614 if (ompt_enabled.ompt_callback_sync_region) { 1615 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 1616 ompt_sync_region_taskwait, ompt_scope_begin, my_parallel_data, 1617 my_task_data, return_address); 1618 } 1619 1620 if (ompt_enabled.ompt_callback_sync_region_wait) { 1621 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 1622 ompt_sync_region_taskwait, ompt_scope_begin, my_parallel_data, 1623 my_task_data, return_address); 1624 } 1625 } 1626 #endif // OMPT_SUPPORT && OMPT_OPTIONAL 1627 1628 // Debugger: The taskwait is active. Store location and thread encountered the 1629 // taskwait. 1630 #if USE_ITT_BUILD 1631 // Note: These values are used by ITT events as well. 1632 #endif /* USE_ITT_BUILD */ 1633 taskdata->td_taskwait_counter += 1; 1634 taskdata->td_taskwait_ident = loc_ref; 1635 taskdata->td_taskwait_thread = gtid + 1; 1636 1637 #if USE_ITT_BUILD 1638 void *itt_sync_obj = __kmp_itt_taskwait_object(gtid); 1639 if (itt_sync_obj != NULL) 1640 __kmp_itt_taskwait_starting(gtid, itt_sync_obj); 1641 #endif /* USE_ITT_BUILD */ 1642 1643 bool must_wait = 1644 !taskdata->td_flags.team_serial && !taskdata->td_flags.final; 1645 1646 #if OMP_45_ENABLED 1647 must_wait = must_wait || (thread->th.th_task_team != NULL && 1648 thread->th.th_task_team->tt.tt_found_proxy_tasks); 1649 #endif 1650 if (must_wait) { 1651 kmp_flag_32 flag( 1652 RCAST(volatile kmp_uint32 *, &taskdata->td_incomplete_child_tasks), 1653 0U); 1654 while (TCR_4(taskdata->td_incomplete_child_tasks) != 0) { 1655 flag.execute_tasks(thread, gtid, FALSE, 1656 &thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), 1657 __kmp_task_stealing_constraint); 1658 } 1659 } 1660 #if USE_ITT_BUILD 1661 if (itt_sync_obj != NULL) 1662 __kmp_itt_taskwait_finished(gtid, itt_sync_obj); 1663 #endif /* USE_ITT_BUILD */ 1664 1665 // Debugger: The taskwait is completed. Location remains, but thread is 1666 // negated. 1667 taskdata->td_taskwait_thread = -taskdata->td_taskwait_thread; 1668 1669 #if OMPT_SUPPORT && OMPT_OPTIONAL 1670 if (ompt) { 1671 if (ompt_enabled.ompt_callback_sync_region_wait) { 1672 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 1673 ompt_sync_region_taskwait, ompt_scope_end, my_parallel_data, 1674 my_task_data, return_address); 1675 } 1676 if (ompt_enabled.ompt_callback_sync_region) { 1677 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 1678 ompt_sync_region_taskwait, ompt_scope_end, my_parallel_data, 1679 my_task_data, return_address); 1680 } 1681 taskdata->ompt_task_info.frame.enter_frame = NULL; 1682 } 1683 #endif // OMPT_SUPPORT && OMPT_OPTIONAL 1684 1685 ANNOTATE_HAPPENS_AFTER(taskdata); 1686 } 1687 1688 KA_TRACE(10, ("__kmpc_omp_taskwait(exit): T#%d task %p finished waiting, " 1689 "returning TASK_CURRENT_NOT_QUEUED\n", 1690 gtid, taskdata)); 1691 1692 return TASK_CURRENT_NOT_QUEUED; 1693 } 1694 1695 #if OMPT_SUPPORT 1696 OMPT_NOINLINE 1697 static kmp_int32 __kmpc_omp_taskwait_ompt(ident_t *loc_ref, kmp_int32 gtid, 1698 void *frame_address, 1699 void *return_address) { 1700 return __kmpc_omp_taskwait_template<true>(loc_ref, gtid, frame_address, 1701 return_address); 1702 } 1703 #endif // OMPT_SUPPORT 1704 1705 // __kmpc_omp_taskwait: Wait until all tasks generated by the current task are 1706 // complete 1707 kmp_int32 __kmpc_omp_taskwait(ident_t *loc_ref, kmp_int32 gtid) { 1708 #if OMPT_SUPPORT && OMPT_OPTIONAL 1709 if (UNLIKELY(ompt_enabled.enabled)) { 1710 OMPT_STORE_RETURN_ADDRESS(gtid); 1711 return __kmpc_omp_taskwait_ompt(loc_ref, gtid, OMPT_GET_FRAME_ADDRESS(1), 1712 OMPT_LOAD_RETURN_ADDRESS(gtid)); 1713 } 1714 #endif 1715 return __kmpc_omp_taskwait_template<false>(loc_ref, gtid, NULL, NULL); 1716 } 1717 1718 // __kmpc_omp_taskyield: switch to a different task 1719 kmp_int32 __kmpc_omp_taskyield(ident_t *loc_ref, kmp_int32 gtid, int end_part) { 1720 kmp_taskdata_t *taskdata; 1721 kmp_info_t *thread; 1722 int thread_finished = FALSE; 1723 1724 KMP_COUNT_BLOCK(OMP_TASKYIELD); 1725 KMP_SET_THREAD_STATE_BLOCK(TASKYIELD); 1726 1727 KA_TRACE(10, ("__kmpc_omp_taskyield(enter): T#%d loc=%p end_part = %d\n", 1728 gtid, loc_ref, end_part)); 1729 1730 if (__kmp_tasking_mode != tskm_immediate_exec && __kmp_init_parallel) { 1731 thread = __kmp_threads[gtid]; 1732 taskdata = thread->th.th_current_task; 1733 // Should we model this as a task wait or not? 1734 // Debugger: The taskwait is active. Store location and thread encountered the 1735 // taskwait. 1736 #if USE_ITT_BUILD 1737 // Note: These values are used by ITT events as well. 1738 #endif /* USE_ITT_BUILD */ 1739 taskdata->td_taskwait_counter += 1; 1740 taskdata->td_taskwait_ident = loc_ref; 1741 taskdata->td_taskwait_thread = gtid + 1; 1742 1743 #if USE_ITT_BUILD 1744 void *itt_sync_obj = __kmp_itt_taskwait_object(gtid); 1745 if (itt_sync_obj != NULL) 1746 __kmp_itt_taskwait_starting(gtid, itt_sync_obj); 1747 #endif /* USE_ITT_BUILD */ 1748 if (!taskdata->td_flags.team_serial) { 1749 kmp_task_team_t *task_team = thread->th.th_task_team; 1750 if (task_team != NULL) { 1751 if (KMP_TASKING_ENABLED(task_team)) { 1752 #if OMPT_SUPPORT 1753 if (UNLIKELY(ompt_enabled.enabled)) 1754 thread->th.ompt_thread_info.ompt_task_yielded = 1; 1755 #endif 1756 __kmp_execute_tasks_32( 1757 thread, gtid, NULL, FALSE, 1758 &thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), 1759 __kmp_task_stealing_constraint); 1760 #if OMPT_SUPPORT 1761 if (UNLIKELY(ompt_enabled.enabled)) 1762 thread->th.ompt_thread_info.ompt_task_yielded = 0; 1763 #endif 1764 } 1765 } 1766 } 1767 #if USE_ITT_BUILD 1768 if (itt_sync_obj != NULL) 1769 __kmp_itt_taskwait_finished(gtid, itt_sync_obj); 1770 #endif /* USE_ITT_BUILD */ 1771 1772 // Debugger: The taskwait is completed. Location remains, but thread is 1773 // negated. 1774 taskdata->td_taskwait_thread = -taskdata->td_taskwait_thread; 1775 } 1776 1777 KA_TRACE(10, ("__kmpc_omp_taskyield(exit): T#%d task %p resuming, " 1778 "returning TASK_CURRENT_NOT_QUEUED\n", 1779 gtid, taskdata)); 1780 1781 return TASK_CURRENT_NOT_QUEUED; 1782 } 1783 1784 // TODO: change to OMP_50_ENABLED, need to change build tools for this to work 1785 #if OMP_45_ENABLED 1786 // Task Reduction implementation 1787 1788 typedef struct kmp_task_red_flags { 1789 unsigned lazy_priv : 1; // hint: (1) use lazy allocation (big objects) 1790 unsigned reserved31 : 31; 1791 } kmp_task_red_flags_t; 1792 1793 // internal structure for reduction data item related info 1794 typedef struct kmp_task_red_data { 1795 void *reduce_shar; // shared reduction item 1796 size_t reduce_size; // size of data item 1797 void *reduce_priv; // thread specific data 1798 void *reduce_pend; // end of private data for comparison op 1799 void *reduce_init; // data initialization routine 1800 void *reduce_fini; // data finalization routine 1801 void *reduce_comb; // data combiner routine 1802 kmp_task_red_flags_t flags; // flags for additional info from compiler 1803 } kmp_task_red_data_t; 1804 1805 // structure sent us by compiler - one per reduction item 1806 typedef struct kmp_task_red_input { 1807 void *reduce_shar; // shared reduction item 1808 size_t reduce_size; // size of data item 1809 void *reduce_init; // data initialization routine 1810 void *reduce_fini; // data finalization routine 1811 void *reduce_comb; // data combiner routine 1812 kmp_task_red_flags_t flags; // flags for additional info from compiler 1813 } kmp_task_red_input_t; 1814 1815 /*! 1816 @ingroup TASKING 1817 @param gtid Global thread ID 1818 @param num Number of data items to reduce 1819 @param data Array of data for reduction 1820 @return The taskgroup identifier 1821 1822 Initialize task reduction for the taskgroup. 1823 */ 1824 void *__kmpc_task_reduction_init(int gtid, int num, void *data) { 1825 kmp_info_t *thread = __kmp_threads[gtid]; 1826 kmp_taskgroup_t *tg = thread->th.th_current_task->td_taskgroup; 1827 kmp_int32 nth = thread->th.th_team_nproc; 1828 kmp_task_red_input_t *input = (kmp_task_red_input_t *)data; 1829 kmp_task_red_data_t *arr; 1830 1831 // check input data just in case 1832 KMP_ASSERT(tg != NULL); 1833 KMP_ASSERT(data != NULL); 1834 KMP_ASSERT(num > 0); 1835 if (nth == 1) { 1836 KA_TRACE(10, ("__kmpc_task_reduction_init: T#%d, tg %p, exiting nth=1\n", 1837 gtid, tg)); 1838 return (void *)tg; 1839 } 1840 KA_TRACE(10, ("__kmpc_task_reduction_init: T#%d, taskgroup %p, #items %d\n", 1841 gtid, tg, num)); 1842 arr = (kmp_task_red_data_t *)__kmp_thread_malloc( 1843 thread, num * sizeof(kmp_task_red_data_t)); 1844 for (int i = 0; i < num; ++i) { 1845 void (*f_init)(void *) = (void (*)(void *))(input[i].reduce_init); 1846 size_t size = input[i].reduce_size - 1; 1847 // round the size up to cache line per thread-specific item 1848 size += CACHE_LINE - size % CACHE_LINE; 1849 KMP_ASSERT(input[i].reduce_comb != NULL); // combiner is mandatory 1850 arr[i].reduce_shar = input[i].reduce_shar; 1851 arr[i].reduce_size = size; 1852 arr[i].reduce_init = input[i].reduce_init; 1853 arr[i].reduce_fini = input[i].reduce_fini; 1854 arr[i].reduce_comb = input[i].reduce_comb; 1855 arr[i].flags = input[i].flags; 1856 if (!input[i].flags.lazy_priv) { 1857 // allocate cache-line aligned block and fill it with zeros 1858 arr[i].reduce_priv = __kmp_allocate(nth * size); 1859 arr[i].reduce_pend = (char *)(arr[i].reduce_priv) + nth * size; 1860 if (f_init != NULL) { 1861 // initialize thread-specific items 1862 for (int j = 0; j < nth; ++j) { 1863 f_init((char *)(arr[i].reduce_priv) + j * size); 1864 } 1865 } 1866 } else { 1867 // only allocate space for pointers now, 1868 // objects will be lazily allocated/initialized once requested 1869 arr[i].reduce_priv = __kmp_allocate(nth * sizeof(void *)); 1870 } 1871 } 1872 tg->reduce_data = (void *)arr; 1873 tg->reduce_num_data = num; 1874 return (void *)tg; 1875 } 1876 1877 /*! 1878 @ingroup TASKING 1879 @param gtid Global thread ID 1880 @param tskgrp The taskgroup ID (optional) 1881 @param data Shared location of the item 1882 @return The pointer to per-thread data 1883 1884 Get thread-specific location of data item 1885 */ 1886 void *__kmpc_task_reduction_get_th_data(int gtid, void *tskgrp, void *data) { 1887 kmp_info_t *thread = __kmp_threads[gtid]; 1888 kmp_int32 nth = thread->th.th_team_nproc; 1889 if (nth == 1) 1890 return data; // nothing to do 1891 1892 kmp_taskgroup_t *tg = (kmp_taskgroup_t *)tskgrp; 1893 if (tg == NULL) 1894 tg = thread->th.th_current_task->td_taskgroup; 1895 KMP_ASSERT(tg != NULL); 1896 kmp_task_red_data_t *arr = (kmp_task_red_data_t *)(tg->reduce_data); 1897 kmp_int32 num = tg->reduce_num_data; 1898 kmp_int32 tid = thread->th.th_info.ds.ds_tid; 1899 1900 KMP_ASSERT(data != NULL); 1901 while (tg != NULL) { 1902 for (int i = 0; i < num; ++i) { 1903 if (!arr[i].flags.lazy_priv) { 1904 if (data == arr[i].reduce_shar || 1905 (data >= arr[i].reduce_priv && data < arr[i].reduce_pend)) 1906 return (char *)(arr[i].reduce_priv) + tid * arr[i].reduce_size; 1907 } else { 1908 // check shared location first 1909 void **p_priv = (void **)(arr[i].reduce_priv); 1910 if (data == arr[i].reduce_shar) 1911 goto found; 1912 // check if we get some thread specific location as parameter 1913 for (int j = 0; j < nth; ++j) 1914 if (data == p_priv[j]) 1915 goto found; 1916 continue; // not found, continue search 1917 found: 1918 if (p_priv[tid] == NULL) { 1919 // allocate thread specific object lazily 1920 void (*f_init)(void *) = (void (*)(void *))(arr[i].reduce_init); 1921 p_priv[tid] = __kmp_allocate(arr[i].reduce_size); 1922 if (f_init != NULL) { 1923 f_init(p_priv[tid]); 1924 } 1925 } 1926 return p_priv[tid]; 1927 } 1928 } 1929 tg = tg->parent; 1930 arr = (kmp_task_red_data_t *)(tg->reduce_data); 1931 num = tg->reduce_num_data; 1932 } 1933 KMP_ASSERT2(0, "Unknown task reduction item"); 1934 return NULL; // ERROR, this line never executed 1935 } 1936 1937 // Finalize task reduction. 1938 // Called from __kmpc_end_taskgroup() 1939 static void __kmp_task_reduction_fini(kmp_info_t *th, kmp_taskgroup_t *tg) { 1940 kmp_int32 nth = th->th.th_team_nproc; 1941 KMP_DEBUG_ASSERT(nth > 1); // should not be called if nth == 1 1942 kmp_task_red_data_t *arr = (kmp_task_red_data_t *)tg->reduce_data; 1943 kmp_int32 num = tg->reduce_num_data; 1944 for (int i = 0; i < num; ++i) { 1945 void *sh_data = arr[i].reduce_shar; 1946 void (*f_fini)(void *) = (void (*)(void *))(arr[i].reduce_fini); 1947 void (*f_comb)(void *, void *) = 1948 (void (*)(void *, void *))(arr[i].reduce_comb); 1949 if (!arr[i].flags.lazy_priv) { 1950 void *pr_data = arr[i].reduce_priv; 1951 size_t size = arr[i].reduce_size; 1952 for (int j = 0; j < nth; ++j) { 1953 void *priv_data = (char *)pr_data + j * size; 1954 f_comb(sh_data, priv_data); // combine results 1955 if (f_fini) 1956 f_fini(priv_data); // finalize if needed 1957 } 1958 } else { 1959 void **pr_data = (void **)(arr[i].reduce_priv); 1960 for (int j = 0; j < nth; ++j) { 1961 if (pr_data[j] != NULL) { 1962 f_comb(sh_data, pr_data[j]); // combine results 1963 if (f_fini) 1964 f_fini(pr_data[j]); // finalize if needed 1965 __kmp_free(pr_data[j]); 1966 } 1967 } 1968 } 1969 __kmp_free(arr[i].reduce_priv); 1970 } 1971 __kmp_thread_free(th, arr); 1972 tg->reduce_data = NULL; 1973 tg->reduce_num_data = 0; 1974 } 1975 #endif 1976 1977 #if OMP_40_ENABLED 1978 // __kmpc_taskgroup: Start a new taskgroup 1979 void __kmpc_taskgroup(ident_t *loc, int gtid) { 1980 kmp_info_t *thread = __kmp_threads[gtid]; 1981 kmp_taskdata_t *taskdata = thread->th.th_current_task; 1982 kmp_taskgroup_t *tg_new = 1983 (kmp_taskgroup_t *)__kmp_thread_malloc(thread, sizeof(kmp_taskgroup_t)); 1984 KA_TRACE(10, ("__kmpc_taskgroup: T#%d loc=%p group=%p\n", gtid, loc, tg_new)); 1985 tg_new->count = 0; 1986 tg_new->cancel_request = cancel_noreq; 1987 tg_new->parent = taskdata->td_taskgroup; 1988 // TODO: change to OMP_50_ENABLED, need to change build tools for this to work 1989 #if OMP_45_ENABLED 1990 tg_new->reduce_data = NULL; 1991 tg_new->reduce_num_data = 0; 1992 #endif 1993 taskdata->td_taskgroup = tg_new; 1994 1995 #if OMPT_SUPPORT && OMPT_OPTIONAL 1996 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region)) { 1997 void *codeptr = OMPT_LOAD_RETURN_ADDRESS(gtid); 1998 if (!codeptr) 1999 codeptr = OMPT_GET_RETURN_ADDRESS(0); 2000 kmp_team_t *team = thread->th.th_team; 2001 ompt_data_t my_task_data = taskdata->ompt_task_info.task_data; 2002 // FIXME: I think this is wrong for lwt! 2003 ompt_data_t my_parallel_data = team->t.ompt_team_info.parallel_data; 2004 2005 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 2006 ompt_sync_region_taskgroup, ompt_scope_begin, &(my_parallel_data), 2007 &(my_task_data), codeptr); 2008 } 2009 #endif 2010 } 2011 2012 // __kmpc_end_taskgroup: Wait until all tasks generated by the current task 2013 // and its descendants are complete 2014 void __kmpc_end_taskgroup(ident_t *loc, int gtid) { 2015 kmp_info_t *thread = __kmp_threads[gtid]; 2016 kmp_taskdata_t *taskdata = thread->th.th_current_task; 2017 kmp_taskgroup_t *taskgroup = taskdata->td_taskgroup; 2018 int thread_finished = FALSE; 2019 2020 #if OMPT_SUPPORT && OMPT_OPTIONAL 2021 kmp_team_t *team; 2022 ompt_data_t my_task_data; 2023 ompt_data_t my_parallel_data; 2024 void *codeptr; 2025 if (UNLIKELY(ompt_enabled.enabled)) { 2026 team = thread->th.th_team; 2027 my_task_data = taskdata->ompt_task_info.task_data; 2028 // FIXME: I think this is wrong for lwt! 2029 my_parallel_data = team->t.ompt_team_info.parallel_data; 2030 codeptr = OMPT_LOAD_RETURN_ADDRESS(gtid); 2031 if (!codeptr) 2032 codeptr = OMPT_GET_RETURN_ADDRESS(0); 2033 } 2034 #endif 2035 2036 KA_TRACE(10, ("__kmpc_end_taskgroup(enter): T#%d loc=%p\n", gtid, loc)); 2037 KMP_DEBUG_ASSERT(taskgroup != NULL); 2038 KMP_SET_THREAD_STATE_BLOCK(TASKGROUP); 2039 2040 if (__kmp_tasking_mode != tskm_immediate_exec) { 2041 // mark task as waiting not on a barrier 2042 taskdata->td_taskwait_counter += 1; 2043 taskdata->td_taskwait_ident = loc; 2044 taskdata->td_taskwait_thread = gtid + 1; 2045 #if USE_ITT_BUILD 2046 // For ITT the taskgroup wait is similar to taskwait until we need to 2047 // distinguish them 2048 void *itt_sync_obj = __kmp_itt_taskwait_object(gtid); 2049 if (itt_sync_obj != NULL) 2050 __kmp_itt_taskwait_starting(gtid, itt_sync_obj); 2051 #endif /* USE_ITT_BUILD */ 2052 2053 #if OMPT_SUPPORT && OMPT_OPTIONAL 2054 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region_wait)) { 2055 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 2056 ompt_sync_region_taskgroup, ompt_scope_begin, &(my_parallel_data), 2057 &(my_task_data), codeptr); 2058 } 2059 #endif 2060 2061 #if OMP_45_ENABLED 2062 if (!taskdata->td_flags.team_serial || 2063 (thread->th.th_task_team != NULL && 2064 thread->th.th_task_team->tt.tt_found_proxy_tasks)) 2065 #else 2066 if (!taskdata->td_flags.team_serial) 2067 #endif 2068 { 2069 kmp_flag_32 flag(RCAST(kmp_uint32 *, &taskgroup->count), 0U); 2070 while (TCR_4(taskgroup->count) != 0) { 2071 flag.execute_tasks(thread, gtid, FALSE, 2072 &thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), 2073 __kmp_task_stealing_constraint); 2074 } 2075 } 2076 taskdata->td_taskwait_thread = -taskdata->td_taskwait_thread; // end waiting 2077 2078 #if OMPT_SUPPORT && OMPT_OPTIONAL 2079 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region_wait)) { 2080 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 2081 ompt_sync_region_taskgroup, ompt_scope_end, &(my_parallel_data), 2082 &(my_task_data), codeptr); 2083 } 2084 #endif 2085 2086 #if USE_ITT_BUILD 2087 if (itt_sync_obj != NULL) 2088 __kmp_itt_taskwait_finished(gtid, itt_sync_obj); 2089 #endif /* USE_ITT_BUILD */ 2090 } 2091 KMP_DEBUG_ASSERT(taskgroup->count == 0); 2092 2093 // TODO: change to OMP_50_ENABLED, need to change build tools for this to work 2094 #if OMP_45_ENABLED 2095 if (taskgroup->reduce_data != NULL) // need to reduce? 2096 __kmp_task_reduction_fini(thread, taskgroup); 2097 #endif 2098 // Restore parent taskgroup for the current task 2099 taskdata->td_taskgroup = taskgroup->parent; 2100 __kmp_thread_free(thread, taskgroup); 2101 2102 KA_TRACE(10, ("__kmpc_end_taskgroup(exit): T#%d task %p finished waiting\n", 2103 gtid, taskdata)); 2104 ANNOTATE_HAPPENS_AFTER(taskdata); 2105 2106 #if OMPT_SUPPORT && OMPT_OPTIONAL 2107 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region)) { 2108 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 2109 ompt_sync_region_taskgroup, ompt_scope_end, &(my_parallel_data), 2110 &(my_task_data), codeptr); 2111 } 2112 #endif 2113 } 2114 #endif 2115 2116 // __kmp_remove_my_task: remove a task from my own deque 2117 static kmp_task_t *__kmp_remove_my_task(kmp_info_t *thread, kmp_int32 gtid, 2118 kmp_task_team_t *task_team, 2119 kmp_int32 is_constrained) { 2120 kmp_task_t *task; 2121 kmp_taskdata_t *taskdata; 2122 kmp_thread_data_t *thread_data; 2123 kmp_uint32 tail; 2124 2125 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 2126 KMP_DEBUG_ASSERT(task_team->tt.tt_threads_data != 2127 NULL); // Caller should check this condition 2128 2129 thread_data = &task_team->tt.tt_threads_data[__kmp_tid_from_gtid(gtid)]; 2130 2131 KA_TRACE(10, ("__kmp_remove_my_task(enter): T#%d ntasks=%d head=%u tail=%u\n", 2132 gtid, thread_data->td.td_deque_ntasks, 2133 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2134 2135 if (TCR_4(thread_data->td.td_deque_ntasks) == 0) { 2136 KA_TRACE(10, 2137 ("__kmp_remove_my_task(exit #1): T#%d No tasks to remove: " 2138 "ntasks=%d head=%u tail=%u\n", 2139 gtid, thread_data->td.td_deque_ntasks, 2140 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2141 return NULL; 2142 } 2143 2144 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 2145 2146 if (TCR_4(thread_data->td.td_deque_ntasks) == 0) { 2147 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2148 KA_TRACE(10, 2149 ("__kmp_remove_my_task(exit #2): T#%d No tasks to remove: " 2150 "ntasks=%d head=%u tail=%u\n", 2151 gtid, thread_data->td.td_deque_ntasks, 2152 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2153 return NULL; 2154 } 2155 2156 tail = (thread_data->td.td_deque_tail - 1) & 2157 TASK_DEQUE_MASK(thread_data->td); // Wrap index. 2158 taskdata = thread_data->td.td_deque[tail]; 2159 2160 if (is_constrained && (taskdata->td_flags.tiedness == TASK_TIED)) { 2161 // we need to check if the candidate obeys task scheduling constraint (TSC) 2162 // only descendant of all deferred tied tasks can be scheduled, checking 2163 // the last one is enough, as it in turn is the descendant of all others 2164 kmp_taskdata_t *current = thread->th.th_current_task->td_last_tied; 2165 KMP_DEBUG_ASSERT(current != NULL); 2166 // check if last tied task is not suspended on barrier 2167 if (current->td_flags.tasktype == TASK_EXPLICIT || 2168 current->td_taskwait_thread > 0) { // <= 0 on barrier 2169 kmp_int32 level = current->td_level; 2170 kmp_taskdata_t *parent = taskdata->td_parent; 2171 while (parent != current && parent->td_level > level) { 2172 parent = parent->td_parent; // check generation up to the level of the 2173 // current task 2174 KMP_DEBUG_ASSERT(parent != NULL); 2175 } 2176 if (parent != current) { 2177 // The TSC does not allow to steal victim task 2178 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2179 KA_TRACE(10, ("__kmp_remove_my_task(exit #2): T#%d No tasks to remove: " 2180 "ntasks=%d head=%u tail=%u\n", 2181 gtid, thread_data->td.td_deque_ntasks, 2182 thread_data->td.td_deque_head, 2183 thread_data->td.td_deque_tail)); 2184 return NULL; 2185 } 2186 } 2187 } 2188 2189 thread_data->td.td_deque_tail = tail; 2190 TCW_4(thread_data->td.td_deque_ntasks, thread_data->td.td_deque_ntasks - 1); 2191 2192 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2193 2194 KA_TRACE(10, ("__kmp_remove_my_task(exit #2): T#%d task %p removed: " 2195 "ntasks=%d head=%u tail=%u\n", 2196 gtid, taskdata, thread_data->td.td_deque_ntasks, 2197 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2198 2199 task = KMP_TASKDATA_TO_TASK(taskdata); 2200 return task; 2201 } 2202 2203 // __kmp_steal_task: remove a task from another thread's deque 2204 // Assume that calling thread has already checked existence of 2205 // task_team thread_data before calling this routine. 2206 static kmp_task_t *__kmp_steal_task(kmp_info_t *victim_thr, kmp_int32 gtid, 2207 kmp_task_team_t *task_team, 2208 volatile kmp_int32 *unfinished_threads, 2209 int *thread_finished, 2210 kmp_int32 is_constrained) { 2211 kmp_task_t *task; 2212 kmp_taskdata_t *taskdata; 2213 kmp_taskdata_t *current; 2214 kmp_thread_data_t *victim_td, *threads_data; 2215 kmp_int32 level, target; 2216 kmp_int32 victim_tid; 2217 2218 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 2219 2220 threads_data = task_team->tt.tt_threads_data; 2221 KMP_DEBUG_ASSERT(threads_data != NULL); // Caller should check this condition 2222 2223 victim_tid = victim_thr->th.th_info.ds.ds_tid; 2224 victim_td = &threads_data[victim_tid]; 2225 2226 KA_TRACE(10, ("__kmp_steal_task(enter): T#%d try to steal from T#%d: " 2227 "task_team=%p ntasks=%d head=%u tail=%u\n", 2228 gtid, __kmp_gtid_from_thread(victim_thr), task_team, 2229 victim_td->td.td_deque_ntasks, victim_td->td.td_deque_head, 2230 victim_td->td.td_deque_tail)); 2231 2232 if (TCR_4(victim_td->td.td_deque_ntasks) == 0) { 2233 KA_TRACE(10, ("__kmp_steal_task(exit #1): T#%d could not steal from T#%d: " 2234 "task_team=%p ntasks=%d head=%u tail=%u\n", 2235 gtid, __kmp_gtid_from_thread(victim_thr), task_team, 2236 victim_td->td.td_deque_ntasks, victim_td->td.td_deque_head, 2237 victim_td->td.td_deque_tail)); 2238 return NULL; 2239 } 2240 2241 __kmp_acquire_bootstrap_lock(&victim_td->td.td_deque_lock); 2242 2243 int ntasks = TCR_4(victim_td->td.td_deque_ntasks); 2244 // Check again after we acquire the lock 2245 if (ntasks == 0) { 2246 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2247 KA_TRACE(10, ("__kmp_steal_task(exit #2): T#%d could not steal from T#%d: " 2248 "task_team=%p ntasks=%d head=%u tail=%u\n", 2249 gtid, __kmp_gtid_from_thread(victim_thr), task_team, ntasks, 2250 victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2251 return NULL; 2252 } 2253 2254 KMP_DEBUG_ASSERT(victim_td->td.td_deque != NULL); 2255 2256 taskdata = victim_td->td.td_deque[victim_td->td.td_deque_head]; 2257 if (is_constrained && (taskdata->td_flags.tiedness == TASK_TIED)) { 2258 // we need to check if the candidate obeys task scheduling constraint (TSC) 2259 // only descendant of all deferred tied tasks can be scheduled, checking 2260 // the last one is enough, as it in turn is the descendant of all others 2261 current = __kmp_threads[gtid]->th.th_current_task->td_last_tied; 2262 KMP_DEBUG_ASSERT(current != NULL); 2263 // check if last tied task is not suspended on barrier 2264 if (current->td_flags.tasktype == TASK_EXPLICIT || 2265 current->td_taskwait_thread > 0) { // <= 0 on barrier 2266 level = current->td_level; 2267 kmp_taskdata_t *parent = taskdata->td_parent; 2268 while (parent != current && parent->td_level > level) { 2269 parent = parent->td_parent; // check generation up to the level of the 2270 // current task 2271 KMP_DEBUG_ASSERT(parent != NULL); 2272 } 2273 if (parent != current) { 2274 if (!task_team->tt.tt_untied_task_encountered) { 2275 // The TSC does not allow to steal victim task 2276 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2277 KA_TRACE(10, 2278 ("__kmp_steal_task(exit #3): T#%d could not steal from " 2279 "T#%d: task_team=%p ntasks=%d head=%u tail=%u\n", 2280 gtid, __kmp_gtid_from_thread(victim_thr), task_team, ntasks, 2281 victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2282 return NULL; 2283 } 2284 taskdata = NULL; // will check other tasks in victim's deque 2285 } 2286 } 2287 } 2288 if (taskdata != NULL) { 2289 // Bump head pointer and Wrap. 2290 victim_td->td.td_deque_head = 2291 (victim_td->td.td_deque_head + 1) & TASK_DEQUE_MASK(victim_td->td); 2292 } else { 2293 int i; 2294 // walk through victim's deque trying to steal any task 2295 target = victim_td->td.td_deque_head; 2296 for (i = 1; i < ntasks; ++i) { 2297 target = (target + 1) & TASK_DEQUE_MASK(victim_td->td); 2298 taskdata = victim_td->td.td_deque[target]; 2299 if (taskdata->td_flags.tiedness == TASK_TIED) { 2300 // check if the candidate obeys the TSC 2301 kmp_taskdata_t *parent = taskdata->td_parent; 2302 // check generation up to the level of the current task 2303 while (parent != current && parent->td_level > level) { 2304 parent = parent->td_parent; 2305 KMP_DEBUG_ASSERT(parent != NULL); 2306 } 2307 if (parent != current) { 2308 // The TSC does not allow to steal the candidate 2309 taskdata = NULL; 2310 continue; 2311 } else { 2312 // found victim tied task 2313 break; 2314 } 2315 } else { 2316 // found victim untied task 2317 break; 2318 } 2319 } 2320 if (taskdata == NULL) { 2321 // No appropriate candidate to steal found 2322 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2323 KA_TRACE(10, ("__kmp_steal_task(exit #4): T#%d could not steal from " 2324 "T#%d: task_team=%p ntasks=%d head=%u tail=%u\n", 2325 gtid, __kmp_gtid_from_thread(victim_thr), task_team, ntasks, 2326 victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2327 return NULL; 2328 } 2329 int prev = target; 2330 for (i = i + 1; i < ntasks; ++i) { 2331 // shift remaining tasks in the deque left by 1 2332 target = (target + 1) & TASK_DEQUE_MASK(victim_td->td); 2333 victim_td->td.td_deque[prev] = victim_td->td.td_deque[target]; 2334 prev = target; 2335 } 2336 KMP_DEBUG_ASSERT(victim_td->td.td_deque_tail == 2337 ((target + 1) & TASK_DEQUE_MASK(victim_td->td))); 2338 victim_td->td.td_deque_tail = target; // tail -= 1 (wrapped)) 2339 } 2340 if (*thread_finished) { 2341 // We need to un-mark this victim as a finished victim. This must be done 2342 // before releasing the lock, or else other threads (starting with the 2343 // master victim) might be prematurely released from the barrier!!! 2344 kmp_int32 count; 2345 2346 count = KMP_TEST_THEN_INC32(unfinished_threads); 2347 2348 KA_TRACE( 2349 20, 2350 ("__kmp_steal_task: T#%d inc unfinished_threads to %d: task_team=%p\n", 2351 gtid, count + 1, task_team)); 2352 2353 *thread_finished = FALSE; 2354 } 2355 TCW_4(victim_td->td.td_deque_ntasks, ntasks - 1); 2356 2357 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2358 2359 KMP_COUNT_BLOCK(TASK_stolen); 2360 KA_TRACE(10, 2361 ("__kmp_steal_task(exit #5): T#%d stole task %p from T#%d: " 2362 "task_team=%p ntasks=%d head=%u tail=%u\n", 2363 gtid, taskdata, __kmp_gtid_from_thread(victim_thr), task_team, 2364 ntasks, victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2365 2366 task = KMP_TASKDATA_TO_TASK(taskdata); 2367 return task; 2368 } 2369 2370 // __kmp_execute_tasks_template: Choose and execute tasks until either the 2371 // condition is statisfied (return true) or there are none left (return false). 2372 // 2373 // final_spin is TRUE if this is the spin at the release barrier. 2374 // thread_finished indicates whether the thread is finished executing all 2375 // the tasks it has on its deque, and is at the release barrier. 2376 // spinner is the location on which to spin. 2377 // spinner == NULL means only execute a single task and return. 2378 // checker is the value to check to terminate the spin. 2379 template <class C> 2380 static inline int __kmp_execute_tasks_template( 2381 kmp_info_t *thread, kmp_int32 gtid, C *flag, int final_spin, 2382 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2383 kmp_int32 is_constrained) { 2384 kmp_task_team_t *task_team = thread->th.th_task_team; 2385 kmp_thread_data_t *threads_data; 2386 kmp_task_t *task; 2387 kmp_info_t *other_thread; 2388 kmp_taskdata_t *current_task = thread->th.th_current_task; 2389 volatile kmp_int32 *unfinished_threads; 2390 kmp_int32 nthreads, victim_tid = -2, use_own_tasks = 1, new_victim = 0, 2391 tid = thread->th.th_info.ds.ds_tid; 2392 2393 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 2394 KMP_DEBUG_ASSERT(thread == __kmp_threads[gtid]); 2395 2396 if (task_team == NULL) 2397 return FALSE; 2398 2399 KA_TRACE(15, ("__kmp_execute_tasks_template(enter): T#%d final_spin=%d " 2400 "*thread_finished=%d\n", 2401 gtid, final_spin, *thread_finished)); 2402 2403 thread->th.th_reap_state = KMP_NOT_SAFE_TO_REAP; 2404 threads_data = (kmp_thread_data_t *)TCR_PTR(task_team->tt.tt_threads_data); 2405 KMP_DEBUG_ASSERT(threads_data != NULL); 2406 2407 nthreads = task_team->tt.tt_nproc; 2408 unfinished_threads = &(task_team->tt.tt_unfinished_threads); 2409 #if OMP_45_ENABLED 2410 KMP_DEBUG_ASSERT(nthreads > 1 || task_team->tt.tt_found_proxy_tasks); 2411 #else 2412 KMP_DEBUG_ASSERT(nthreads > 1); 2413 #endif 2414 KMP_DEBUG_ASSERT(TCR_4(*unfinished_threads) >= 0); 2415 2416 while (1) { // Outer loop keeps trying to find tasks in case of single thread 2417 // getting tasks from target constructs 2418 while (1) { // Inner loop to find a task and execute it 2419 task = NULL; 2420 if (use_own_tasks) { // check on own queue first 2421 task = __kmp_remove_my_task(thread, gtid, task_team, is_constrained); 2422 } 2423 if ((task == NULL) && (nthreads > 1)) { // Steal a task 2424 int asleep = 1; 2425 use_own_tasks = 0; 2426 // Try to steal from the last place I stole from successfully. 2427 if (victim_tid == -2) { // haven't stolen anything yet 2428 victim_tid = threads_data[tid].td.td_deque_last_stolen; 2429 if (victim_tid != 2430 -1) // if we have a last stolen from victim, get the thread 2431 other_thread = threads_data[victim_tid].td.td_thr; 2432 } 2433 if (victim_tid != -1) { // found last victim 2434 asleep = 0; 2435 } else if (!new_victim) { // no recent steals and we haven't already 2436 // used a new victim; select a random thread 2437 do { // Find a different thread to steal work from. 2438 // Pick a random thread. Initial plan was to cycle through all the 2439 // threads, and only return if we tried to steal from every thread, 2440 // and failed. Arch says that's not such a great idea. 2441 victim_tid = __kmp_get_random(thread) % (nthreads - 1); 2442 if (victim_tid >= tid) { 2443 ++victim_tid; // Adjusts random distribution to exclude self 2444 } 2445 // Found a potential victim 2446 other_thread = threads_data[victim_tid].td.td_thr; 2447 // There is a slight chance that __kmp_enable_tasking() did not wake 2448 // up all threads waiting at the barrier. If victim is sleeping, 2449 // then wake it up. Since we were going to pay the cache miss 2450 // penalty for referencing another thread's kmp_info_t struct 2451 // anyway, 2452 // the check shouldn't cost too much performance at this point. In 2453 // extra barrier mode, tasks do not sleep at the separate tasking 2454 // barrier, so this isn't a problem. 2455 asleep = 0; 2456 if ((__kmp_tasking_mode == tskm_task_teams) && 2457 (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME) && 2458 (TCR_PTR(CCAST(void *, other_thread->th.th_sleep_loc)) != 2459 NULL)) { 2460 asleep = 1; 2461 __kmp_null_resume_wrapper(__kmp_gtid_from_thread(other_thread), 2462 other_thread->th.th_sleep_loc); 2463 // A sleeping thread should not have any tasks on it's queue. 2464 // There is a slight possibility that it resumes, steals a task 2465 // from another thread, which spawns more tasks, all in the time 2466 // that it takes this thread to check => don't write an assertion 2467 // that the victim's queue is empty. Try stealing from a 2468 // different thread. 2469 } 2470 } while (asleep); 2471 } 2472 2473 if (!asleep) { 2474 // We have a victim to try to steal from 2475 task = __kmp_steal_task(other_thread, gtid, task_team, 2476 unfinished_threads, thread_finished, 2477 is_constrained); 2478 } 2479 if (task != NULL) { // set last stolen to victim 2480 if (threads_data[tid].td.td_deque_last_stolen != victim_tid) { 2481 threads_data[tid].td.td_deque_last_stolen = victim_tid; 2482 // The pre-refactored code did not try more than 1 successful new 2483 // vicitm, unless the last one generated more local tasks; 2484 // new_victim keeps track of this 2485 new_victim = 1; 2486 } 2487 } else { // No tasks found; unset last_stolen 2488 KMP_CHECK_UPDATE(threads_data[tid].td.td_deque_last_stolen, -1); 2489 victim_tid = -2; // no successful victim found 2490 } 2491 } 2492 2493 if (task == NULL) // break out of tasking loop 2494 break; 2495 2496 // Found a task; execute it 2497 #if USE_ITT_BUILD && USE_ITT_NOTIFY 2498 if (__itt_sync_create_ptr || KMP_ITT_DEBUG) { 2499 if (itt_sync_obj == NULL) { // we are at fork barrier where we could not 2500 // get the object reliably 2501 itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier); 2502 } 2503 __kmp_itt_task_starting(itt_sync_obj); 2504 } 2505 #endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */ 2506 __kmp_invoke_task(gtid, task, current_task); 2507 #if USE_ITT_BUILD 2508 if (itt_sync_obj != NULL) 2509 __kmp_itt_task_finished(itt_sync_obj); 2510 #endif /* USE_ITT_BUILD */ 2511 // If this thread is only partway through the barrier and the condition is 2512 // met, then return now, so that the barrier gather/release pattern can 2513 // proceed. If this thread is in the last spin loop in the barrier, 2514 // waiting to be released, we know that the termination condition will not 2515 // be satisified, so don't waste any cycles checking it. 2516 if (flag == NULL || (!final_spin && flag->done_check())) { 2517 KA_TRACE( 2518 15, 2519 ("__kmp_execute_tasks_template: T#%d spin condition satisfied\n", 2520 gtid)); 2521 return TRUE; 2522 } 2523 if (thread->th.th_task_team == NULL) { 2524 break; 2525 } 2526 // Yield before executing next task 2527 KMP_YIELD(__kmp_library == library_throughput); 2528 // If execution of a stolen task results in more tasks being placed on our 2529 // run queue, reset use_own_tasks 2530 if (!use_own_tasks && TCR_4(threads_data[tid].td.td_deque_ntasks) != 0) { 2531 KA_TRACE(20, ("__kmp_execute_tasks_template: T#%d stolen task spawned " 2532 "other tasks, restart\n", 2533 gtid)); 2534 use_own_tasks = 1; 2535 new_victim = 0; 2536 } 2537 } 2538 2539 // The task source has been exhausted. If in final spin loop of barrier, check 2540 // if termination condition is satisfied. 2541 #if OMP_45_ENABLED 2542 // The work queue may be empty but there might be proxy tasks still 2543 // executing 2544 if (final_spin && TCR_4(current_task->td_incomplete_child_tasks) == 0) 2545 #else 2546 if (final_spin) 2547 #endif 2548 { 2549 // First, decrement the #unfinished threads, if that has not already been 2550 // done. This decrement might be to the spin location, and result in the 2551 // termination condition being satisfied. 2552 if (!*thread_finished) { 2553 kmp_int32 count; 2554 2555 count = KMP_TEST_THEN_DEC32(unfinished_threads) - 1; 2556 KA_TRACE(20, ("__kmp_execute_tasks_template: T#%d dec " 2557 "unfinished_threads to %d task_team=%p\n", 2558 gtid, count, task_team)); 2559 *thread_finished = TRUE; 2560 } 2561 2562 // It is now unsafe to reference thread->th.th_team !!! 2563 // Decrementing task_team->tt.tt_unfinished_threads can allow the master 2564 // thread to pass through the barrier, where it might reset each thread's 2565 // th.th_team field for the next parallel region. If we can steal more 2566 // work, we know that this has not happened yet. 2567 if (flag != NULL && flag->done_check()) { 2568 KA_TRACE( 2569 15, 2570 ("__kmp_execute_tasks_template: T#%d spin condition satisfied\n", 2571 gtid)); 2572 return TRUE; 2573 } 2574 } 2575 2576 // If this thread's task team is NULL, master has recognized that there are 2577 // no more tasks; bail out 2578 if (thread->th.th_task_team == NULL) { 2579 KA_TRACE(15, 2580 ("__kmp_execute_tasks_template: T#%d no more tasks\n", gtid)); 2581 return FALSE; 2582 } 2583 2584 #if OMP_45_ENABLED 2585 // We could be getting tasks from target constructs; if this is the only 2586 // thread, keep trying to execute tasks from own queue 2587 if (nthreads == 1) 2588 use_own_tasks = 1; 2589 else 2590 #endif 2591 { 2592 KA_TRACE(15, 2593 ("__kmp_execute_tasks_template: T#%d can't find work\n", gtid)); 2594 return FALSE; 2595 } 2596 } 2597 } 2598 2599 int __kmp_execute_tasks_32( 2600 kmp_info_t *thread, kmp_int32 gtid, kmp_flag_32 *flag, int final_spin, 2601 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2602 kmp_int32 is_constrained) { 2603 return __kmp_execute_tasks_template( 2604 thread, gtid, flag, final_spin, 2605 thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), is_constrained); 2606 } 2607 2608 int __kmp_execute_tasks_64( 2609 kmp_info_t *thread, kmp_int32 gtid, kmp_flag_64 *flag, int final_spin, 2610 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2611 kmp_int32 is_constrained) { 2612 return __kmp_execute_tasks_template( 2613 thread, gtid, flag, final_spin, 2614 thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), is_constrained); 2615 } 2616 2617 int __kmp_execute_tasks_oncore( 2618 kmp_info_t *thread, kmp_int32 gtid, kmp_flag_oncore *flag, int final_spin, 2619 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2620 kmp_int32 is_constrained) { 2621 return __kmp_execute_tasks_template( 2622 thread, gtid, flag, final_spin, 2623 thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), is_constrained); 2624 } 2625 2626 // __kmp_enable_tasking: Allocate task team and resume threads sleeping at the 2627 // next barrier so they can assist in executing enqueued tasks. 2628 // First thread in allocates the task team atomically. 2629 static void __kmp_enable_tasking(kmp_task_team_t *task_team, 2630 kmp_info_t *this_thr) { 2631 kmp_thread_data_t *threads_data; 2632 int nthreads, i, is_init_thread; 2633 2634 KA_TRACE(10, ("__kmp_enable_tasking(enter): T#%d\n", 2635 __kmp_gtid_from_thread(this_thr))); 2636 2637 KMP_DEBUG_ASSERT(task_team != NULL); 2638 KMP_DEBUG_ASSERT(this_thr->th.th_team != NULL); 2639 2640 nthreads = task_team->tt.tt_nproc; 2641 KMP_DEBUG_ASSERT(nthreads > 0); 2642 KMP_DEBUG_ASSERT(nthreads == this_thr->th.th_team->t.t_nproc); 2643 2644 // Allocate or increase the size of threads_data if necessary 2645 is_init_thread = __kmp_realloc_task_threads_data(this_thr, task_team); 2646 2647 if (!is_init_thread) { 2648 // Some other thread already set up the array. 2649 KA_TRACE( 2650 20, 2651 ("__kmp_enable_tasking(exit): T#%d: threads array already set up.\n", 2652 __kmp_gtid_from_thread(this_thr))); 2653 return; 2654 } 2655 threads_data = (kmp_thread_data_t *)TCR_PTR(task_team->tt.tt_threads_data); 2656 KMP_DEBUG_ASSERT(threads_data != NULL); 2657 2658 if ((__kmp_tasking_mode == tskm_task_teams) && 2659 (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME)) { 2660 // Release any threads sleeping at the barrier, so that they can steal 2661 // tasks and execute them. In extra barrier mode, tasks do not sleep 2662 // at the separate tasking barrier, so this isn't a problem. 2663 for (i = 0; i < nthreads; i++) { 2664 volatile void *sleep_loc; 2665 kmp_info_t *thread = threads_data[i].td.td_thr; 2666 2667 if (i == this_thr->th.th_info.ds.ds_tid) { 2668 continue; 2669 } 2670 // Since we haven't locked the thread's suspend mutex lock at this 2671 // point, there is a small window where a thread might be putting 2672 // itself to sleep, but hasn't set the th_sleep_loc field yet. 2673 // To work around this, __kmp_execute_tasks_template() periodically checks 2674 // see if other threads are sleeping (using the same random mechanism that 2675 // is used for task stealing) and awakens them if they are. 2676 if ((sleep_loc = TCR_PTR(CCAST(void *, thread->th.th_sleep_loc))) != 2677 NULL) { 2678 KF_TRACE(50, ("__kmp_enable_tasking: T#%d waking up thread T#%d\n", 2679 __kmp_gtid_from_thread(this_thr), 2680 __kmp_gtid_from_thread(thread))); 2681 __kmp_null_resume_wrapper(__kmp_gtid_from_thread(thread), sleep_loc); 2682 } else { 2683 KF_TRACE(50, ("__kmp_enable_tasking: T#%d don't wake up thread T#%d\n", 2684 __kmp_gtid_from_thread(this_thr), 2685 __kmp_gtid_from_thread(thread))); 2686 } 2687 } 2688 } 2689 2690 KA_TRACE(10, ("__kmp_enable_tasking(exit): T#%d\n", 2691 __kmp_gtid_from_thread(this_thr))); 2692 } 2693 2694 /* // TODO: Check the comment consistency 2695 * Utility routines for "task teams". A task team (kmp_task_t) is kind of 2696 * like a shadow of the kmp_team_t data struct, with a different lifetime. 2697 * After a child * thread checks into a barrier and calls __kmp_release() from 2698 * the particular variant of __kmp_<barrier_kind>_barrier_gather(), it can no 2699 * longer assume that the kmp_team_t structure is intact (at any moment, the 2700 * master thread may exit the barrier code and free the team data structure, 2701 * and return the threads to the thread pool). 2702 * 2703 * This does not work with the the tasking code, as the thread is still 2704 * expected to participate in the execution of any tasks that may have been 2705 * spawned my a member of the team, and the thread still needs access to all 2706 * to each thread in the team, so that it can steal work from it. 2707 * 2708 * Enter the existence of the kmp_task_team_t struct. It employs a reference 2709 * counting mechanims, and is allocated by the master thread before calling 2710 * __kmp_<barrier_kind>_release, and then is release by the last thread to 2711 * exit __kmp_<barrier_kind>_release at the next barrier. I.e. the lifetimes 2712 * of the kmp_task_team_t structs for consecutive barriers can overlap 2713 * (and will, unless the master thread is the last thread to exit the barrier 2714 * release phase, which is not typical). 2715 * 2716 * The existence of such a struct is useful outside the context of tasking, 2717 * but for now, I'm trying to keep it specific to the OMP_30_ENABLED macro, 2718 * so that any performance differences show up when comparing the 2.5 vs. 3.0 2719 * libraries. 2720 * 2721 * We currently use the existence of the threads array as an indicator that 2722 * tasks were spawned since the last barrier. If the structure is to be 2723 * useful outside the context of tasking, then this will have to change, but 2724 * not settting the field minimizes the performance impact of tasking on 2725 * barriers, when no explicit tasks were spawned (pushed, actually). 2726 */ 2727 2728 static kmp_task_team_t *__kmp_free_task_teams = 2729 NULL; // Free list for task_team data structures 2730 // Lock for task team data structures 2731 kmp_bootstrap_lock_t __kmp_task_team_lock = 2732 KMP_BOOTSTRAP_LOCK_INITIALIZER(__kmp_task_team_lock); 2733 2734 // __kmp_alloc_task_deque: 2735 // Allocates a task deque for a particular thread, and initialize the necessary 2736 // data structures relating to the deque. This only happens once per thread 2737 // per task team since task teams are recycled. No lock is needed during 2738 // allocation since each thread allocates its own deque. 2739 static void __kmp_alloc_task_deque(kmp_info_t *thread, 2740 kmp_thread_data_t *thread_data) { 2741 __kmp_init_bootstrap_lock(&thread_data->td.td_deque_lock); 2742 KMP_DEBUG_ASSERT(thread_data->td.td_deque == NULL); 2743 2744 // Initialize last stolen task field to "none" 2745 thread_data->td.td_deque_last_stolen = -1; 2746 2747 KMP_DEBUG_ASSERT(TCR_4(thread_data->td.td_deque_ntasks) == 0); 2748 KMP_DEBUG_ASSERT(thread_data->td.td_deque_head == 0); 2749 KMP_DEBUG_ASSERT(thread_data->td.td_deque_tail == 0); 2750 2751 KE_TRACE( 2752 10, 2753 ("__kmp_alloc_task_deque: T#%d allocating deque[%d] for thread_data %p\n", 2754 __kmp_gtid_from_thread(thread), INITIAL_TASK_DEQUE_SIZE, thread_data)); 2755 // Allocate space for task deque, and zero the deque 2756 // Cannot use __kmp_thread_calloc() because threads not around for 2757 // kmp_reap_task_team( ). 2758 thread_data->td.td_deque = (kmp_taskdata_t **)__kmp_allocate( 2759 INITIAL_TASK_DEQUE_SIZE * sizeof(kmp_taskdata_t *)); 2760 thread_data->td.td_deque_size = INITIAL_TASK_DEQUE_SIZE; 2761 } 2762 2763 // __kmp_realloc_task_deque: 2764 // Re-allocates a task deque for a particular thread, copies the content from 2765 // the old deque and adjusts the necessary data structures relating to the 2766 // deque. This operation must be done with a the deque_lock being held 2767 static void __kmp_realloc_task_deque(kmp_info_t *thread, 2768 kmp_thread_data_t *thread_data) { 2769 kmp_int32 size = TASK_DEQUE_SIZE(thread_data->td); 2770 kmp_int32 new_size = 2 * size; 2771 2772 KE_TRACE(10, ("__kmp_realloc_task_deque: T#%d reallocating deque[from %d to " 2773 "%d] for thread_data %p\n", 2774 __kmp_gtid_from_thread(thread), size, new_size, thread_data)); 2775 2776 kmp_taskdata_t **new_deque = 2777 (kmp_taskdata_t **)__kmp_allocate(new_size * sizeof(kmp_taskdata_t *)); 2778 2779 int i, j; 2780 for (i = thread_data->td.td_deque_head, j = 0; j < size; 2781 i = (i + 1) & TASK_DEQUE_MASK(thread_data->td), j++) 2782 new_deque[j] = thread_data->td.td_deque[i]; 2783 2784 __kmp_free(thread_data->td.td_deque); 2785 2786 thread_data->td.td_deque_head = 0; 2787 thread_data->td.td_deque_tail = size; 2788 thread_data->td.td_deque = new_deque; 2789 thread_data->td.td_deque_size = new_size; 2790 } 2791 2792 // __kmp_free_task_deque: 2793 // Deallocates a task deque for a particular thread. Happens at library 2794 // deallocation so don't need to reset all thread data fields. 2795 static void __kmp_free_task_deque(kmp_thread_data_t *thread_data) { 2796 if (thread_data->td.td_deque != NULL) { 2797 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 2798 TCW_4(thread_data->td.td_deque_ntasks, 0); 2799 __kmp_free(thread_data->td.td_deque); 2800 thread_data->td.td_deque = NULL; 2801 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2802 } 2803 2804 #ifdef BUILD_TIED_TASK_STACK 2805 // GEH: Figure out what to do here for td_susp_tied_tasks 2806 if (thread_data->td.td_susp_tied_tasks.ts_entries != TASK_STACK_EMPTY) { 2807 __kmp_free_task_stack(__kmp_thread_from_gtid(gtid), thread_data); 2808 } 2809 #endif // BUILD_TIED_TASK_STACK 2810 } 2811 2812 // __kmp_realloc_task_threads_data: 2813 // Allocates a threads_data array for a task team, either by allocating an 2814 // initial array or enlarging an existing array. Only the first thread to get 2815 // the lock allocs or enlarges the array and re-initializes the array eleemnts. 2816 // That thread returns "TRUE", the rest return "FALSE". 2817 // Assumes that the new array size is given by task_team -> tt.tt_nproc. 2818 // The current size is given by task_team -> tt.tt_max_threads. 2819 static int __kmp_realloc_task_threads_data(kmp_info_t *thread, 2820 kmp_task_team_t *task_team) { 2821 kmp_thread_data_t **threads_data_p; 2822 kmp_int32 nthreads, maxthreads; 2823 int is_init_thread = FALSE; 2824 2825 if (TCR_4(task_team->tt.tt_found_tasks)) { 2826 // Already reallocated and initialized. 2827 return FALSE; 2828 } 2829 2830 threads_data_p = &task_team->tt.tt_threads_data; 2831 nthreads = task_team->tt.tt_nproc; 2832 maxthreads = task_team->tt.tt_max_threads; 2833 2834 // All threads must lock when they encounter the first task of the implicit 2835 // task region to make sure threads_data fields are (re)initialized before 2836 // used. 2837 __kmp_acquire_bootstrap_lock(&task_team->tt.tt_threads_lock); 2838 2839 if (!TCR_4(task_team->tt.tt_found_tasks)) { 2840 // first thread to enable tasking 2841 kmp_team_t *team = thread->th.th_team; 2842 int i; 2843 2844 is_init_thread = TRUE; 2845 if (maxthreads < nthreads) { 2846 2847 if (*threads_data_p != NULL) { 2848 kmp_thread_data_t *old_data = *threads_data_p; 2849 kmp_thread_data_t *new_data = NULL; 2850 2851 KE_TRACE( 2852 10, 2853 ("__kmp_realloc_task_threads_data: T#%d reallocating " 2854 "threads data for task_team %p, new_size = %d, old_size = %d\n", 2855 __kmp_gtid_from_thread(thread), task_team, nthreads, maxthreads)); 2856 // Reallocate threads_data to have more elements than current array 2857 // Cannot use __kmp_thread_realloc() because threads not around for 2858 // kmp_reap_task_team( ). Note all new array entries are initialized 2859 // to zero by __kmp_allocate(). 2860 new_data = (kmp_thread_data_t *)__kmp_allocate( 2861 nthreads * sizeof(kmp_thread_data_t)); 2862 // copy old data to new data 2863 KMP_MEMCPY_S((void *)new_data, nthreads * sizeof(kmp_thread_data_t), 2864 (void *)old_data, maxthreads * sizeof(kmp_thread_data_t)); 2865 2866 #ifdef BUILD_TIED_TASK_STACK 2867 // GEH: Figure out if this is the right thing to do 2868 for (i = maxthreads; i < nthreads; i++) { 2869 kmp_thread_data_t *thread_data = &(*threads_data_p)[i]; 2870 __kmp_init_task_stack(__kmp_gtid_from_thread(thread), thread_data); 2871 } 2872 #endif // BUILD_TIED_TASK_STACK 2873 // Install the new data and free the old data 2874 (*threads_data_p) = new_data; 2875 __kmp_free(old_data); 2876 } else { 2877 KE_TRACE(10, ("__kmp_realloc_task_threads_data: T#%d allocating " 2878 "threads data for task_team %p, size = %d\n", 2879 __kmp_gtid_from_thread(thread), task_team, nthreads)); 2880 // Make the initial allocate for threads_data array, and zero entries 2881 // Cannot use __kmp_thread_calloc() because threads not around for 2882 // kmp_reap_task_team( ). 2883 ANNOTATE_IGNORE_WRITES_BEGIN(); 2884 *threads_data_p = (kmp_thread_data_t *)__kmp_allocate( 2885 nthreads * sizeof(kmp_thread_data_t)); 2886 ANNOTATE_IGNORE_WRITES_END(); 2887 #ifdef BUILD_TIED_TASK_STACK 2888 // GEH: Figure out if this is the right thing to do 2889 for (i = 0; i < nthreads; i++) { 2890 kmp_thread_data_t *thread_data = &(*threads_data_p)[i]; 2891 __kmp_init_task_stack(__kmp_gtid_from_thread(thread), thread_data); 2892 } 2893 #endif // BUILD_TIED_TASK_STACK 2894 } 2895 task_team->tt.tt_max_threads = nthreads; 2896 } else { 2897 // If array has (more than) enough elements, go ahead and use it 2898 KMP_DEBUG_ASSERT(*threads_data_p != NULL); 2899 } 2900 2901 // initialize threads_data pointers back to thread_info structures 2902 for (i = 0; i < nthreads; i++) { 2903 kmp_thread_data_t *thread_data = &(*threads_data_p)[i]; 2904 thread_data->td.td_thr = team->t.t_threads[i]; 2905 2906 if (thread_data->td.td_deque_last_stolen >= nthreads) { 2907 // The last stolen field survives across teams / barrier, and the number 2908 // of threads may have changed. It's possible (likely?) that a new 2909 // parallel region will exhibit the same behavior as previous region. 2910 thread_data->td.td_deque_last_stolen = -1; 2911 } 2912 } 2913 2914 KMP_MB(); 2915 TCW_SYNC_4(task_team->tt.tt_found_tasks, TRUE); 2916 } 2917 2918 __kmp_release_bootstrap_lock(&task_team->tt.tt_threads_lock); 2919 return is_init_thread; 2920 } 2921 2922 // __kmp_free_task_threads_data: 2923 // Deallocates a threads_data array for a task team, including any attached 2924 // tasking deques. Only occurs at library shutdown. 2925 static void __kmp_free_task_threads_data(kmp_task_team_t *task_team) { 2926 __kmp_acquire_bootstrap_lock(&task_team->tt.tt_threads_lock); 2927 if (task_team->tt.tt_threads_data != NULL) { 2928 int i; 2929 for (i = 0; i < task_team->tt.tt_max_threads; i++) { 2930 __kmp_free_task_deque(&task_team->tt.tt_threads_data[i]); 2931 } 2932 __kmp_free(task_team->tt.tt_threads_data); 2933 task_team->tt.tt_threads_data = NULL; 2934 } 2935 __kmp_release_bootstrap_lock(&task_team->tt.tt_threads_lock); 2936 } 2937 2938 // __kmp_allocate_task_team: 2939 // Allocates a task team associated with a specific team, taking it from 2940 // the global task team free list if possible. Also initializes data 2941 // structures. 2942 static kmp_task_team_t *__kmp_allocate_task_team(kmp_info_t *thread, 2943 kmp_team_t *team) { 2944 kmp_task_team_t *task_team = NULL; 2945 int nthreads; 2946 2947 KA_TRACE(20, ("__kmp_allocate_task_team: T#%d entering; team = %p\n", 2948 (thread ? __kmp_gtid_from_thread(thread) : -1), team)); 2949 2950 if (TCR_PTR(__kmp_free_task_teams) != NULL) { 2951 // Take a task team from the task team pool 2952 __kmp_acquire_bootstrap_lock(&__kmp_task_team_lock); 2953 if (__kmp_free_task_teams != NULL) { 2954 task_team = __kmp_free_task_teams; 2955 TCW_PTR(__kmp_free_task_teams, task_team->tt.tt_next); 2956 task_team->tt.tt_next = NULL; 2957 } 2958 __kmp_release_bootstrap_lock(&__kmp_task_team_lock); 2959 } 2960 2961 if (task_team == NULL) { 2962 KE_TRACE(10, ("__kmp_allocate_task_team: T#%d allocating " 2963 "task team for team %p\n", 2964 __kmp_gtid_from_thread(thread), team)); 2965 // Allocate a new task team if one is not available. 2966 // Cannot use __kmp_thread_malloc() because threads not around for 2967 // kmp_reap_task_team( ). 2968 task_team = (kmp_task_team_t *)__kmp_allocate(sizeof(kmp_task_team_t)); 2969 __kmp_init_bootstrap_lock(&task_team->tt.tt_threads_lock); 2970 // AC: __kmp_allocate zeroes returned memory 2971 // task_team -> tt.tt_threads_data = NULL; 2972 // task_team -> tt.tt_max_threads = 0; 2973 // task_team -> tt.tt_next = NULL; 2974 } 2975 2976 TCW_4(task_team->tt.tt_found_tasks, FALSE); 2977 #if OMP_45_ENABLED 2978 TCW_4(task_team->tt.tt_found_proxy_tasks, FALSE); 2979 #endif 2980 task_team->tt.tt_nproc = nthreads = team->t.t_nproc; 2981 2982 TCW_4(task_team->tt.tt_unfinished_threads, nthreads); 2983 TCW_4(task_team->tt.tt_active, TRUE); 2984 2985 KA_TRACE(20, ("__kmp_allocate_task_team: T#%d exiting; task_team = %p " 2986 "unfinished_threads init'd to %d\n", 2987 (thread ? __kmp_gtid_from_thread(thread) : -1), task_team, 2988 task_team->tt.tt_unfinished_threads)); 2989 return task_team; 2990 } 2991 2992 // __kmp_free_task_team: 2993 // Frees the task team associated with a specific thread, and adds it 2994 // to the global task team free list. 2995 void __kmp_free_task_team(kmp_info_t *thread, kmp_task_team_t *task_team) { 2996 KA_TRACE(20, ("__kmp_free_task_team: T#%d task_team = %p\n", 2997 thread ? __kmp_gtid_from_thread(thread) : -1, task_team)); 2998 2999 // Put task team back on free list 3000 __kmp_acquire_bootstrap_lock(&__kmp_task_team_lock); 3001 3002 KMP_DEBUG_ASSERT(task_team->tt.tt_next == NULL); 3003 task_team->tt.tt_next = __kmp_free_task_teams; 3004 TCW_PTR(__kmp_free_task_teams, task_team); 3005 3006 __kmp_release_bootstrap_lock(&__kmp_task_team_lock); 3007 } 3008 3009 // __kmp_reap_task_teams: 3010 // Free all the task teams on the task team free list. 3011 // Should only be done during library shutdown. 3012 // Cannot do anything that needs a thread structure or gtid since they are 3013 // already gone. 3014 void __kmp_reap_task_teams(void) { 3015 kmp_task_team_t *task_team; 3016 3017 if (TCR_PTR(__kmp_free_task_teams) != NULL) { 3018 // Free all task_teams on the free list 3019 __kmp_acquire_bootstrap_lock(&__kmp_task_team_lock); 3020 while ((task_team = __kmp_free_task_teams) != NULL) { 3021 __kmp_free_task_teams = task_team->tt.tt_next; 3022 task_team->tt.tt_next = NULL; 3023 3024 // Free threads_data if necessary 3025 if (task_team->tt.tt_threads_data != NULL) { 3026 __kmp_free_task_threads_data(task_team); 3027 } 3028 __kmp_free(task_team); 3029 } 3030 __kmp_release_bootstrap_lock(&__kmp_task_team_lock); 3031 } 3032 } 3033 3034 // __kmp_wait_to_unref_task_teams: 3035 // Some threads could still be in the fork barrier release code, possibly 3036 // trying to steal tasks. Wait for each thread to unreference its task team. 3037 void __kmp_wait_to_unref_task_teams(void) { 3038 kmp_info_t *thread; 3039 kmp_uint32 spins; 3040 int done; 3041 3042 KMP_INIT_YIELD(spins); 3043 3044 for (;;) { 3045 done = TRUE; 3046 3047 // TODO: GEH - this may be is wrong because some sync would be necessary 3048 // in case threads are added to the pool during the traversal. Need to 3049 // verify that lock for thread pool is held when calling this routine. 3050 for (thread = CCAST(kmp_info_t *, __kmp_thread_pool); thread != NULL; 3051 thread = thread->th.th_next_pool) { 3052 #if KMP_OS_WINDOWS 3053 DWORD exit_val; 3054 #endif 3055 if (TCR_PTR(thread->th.th_task_team) == NULL) { 3056 KA_TRACE(10, ("__kmp_wait_to_unref_task_team: T#%d task_team == NULL\n", 3057 __kmp_gtid_from_thread(thread))); 3058 continue; 3059 } 3060 #if KMP_OS_WINDOWS 3061 // TODO: GEH - add this check for Linux* OS / OS X* as well? 3062 if (!__kmp_is_thread_alive(thread, &exit_val)) { 3063 thread->th.th_task_team = NULL; 3064 continue; 3065 } 3066 #endif 3067 3068 done = FALSE; // Because th_task_team pointer is not NULL for this thread 3069 3070 KA_TRACE(10, ("__kmp_wait_to_unref_task_team: Waiting for T#%d to " 3071 "unreference task_team\n", 3072 __kmp_gtid_from_thread(thread))); 3073 3074 if (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME) { 3075 volatile void *sleep_loc; 3076 // If the thread is sleeping, awaken it. 3077 if ((sleep_loc = TCR_PTR(CCAST(void *, thread->th.th_sleep_loc))) != 3078 NULL) { 3079 KA_TRACE( 3080 10, 3081 ("__kmp_wait_to_unref_task_team: T#%d waking up thread T#%d\n", 3082 __kmp_gtid_from_thread(thread), __kmp_gtid_from_thread(thread))); 3083 __kmp_null_resume_wrapper(__kmp_gtid_from_thread(thread), sleep_loc); 3084 } 3085 } 3086 } 3087 if (done) { 3088 break; 3089 } 3090 3091 // If we are oversubscribed, or have waited a bit (and library mode is 3092 // throughput), yield. Pause is in the following code. 3093 KMP_YIELD(TCR_4(__kmp_nth) > __kmp_avail_proc); 3094 KMP_YIELD_SPIN(spins); // Yields only if KMP_LIBRARY=throughput 3095 } 3096 } 3097 3098 // __kmp_task_team_setup: Create a task_team for the current team, but use 3099 // an already created, unused one if it already exists. 3100 void __kmp_task_team_setup(kmp_info_t *this_thr, kmp_team_t *team, int always) { 3101 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 3102 3103 // If this task_team hasn't been created yet, allocate it. It will be used in 3104 // the region after the next. 3105 // If it exists, it is the current task team and shouldn't be touched yet as 3106 // it may still be in use. 3107 if (team->t.t_task_team[this_thr->th.th_task_state] == NULL && 3108 (always || team->t.t_nproc > 1)) { 3109 team->t.t_task_team[this_thr->th.th_task_state] = 3110 __kmp_allocate_task_team(this_thr, team); 3111 KA_TRACE(20, ("__kmp_task_team_setup: Master T#%d created new task_team %p " 3112 "for team %d at parity=%d\n", 3113 __kmp_gtid_from_thread(this_thr), 3114 team->t.t_task_team[this_thr->th.th_task_state], 3115 ((team != NULL) ? team->t.t_id : -1), 3116 this_thr->th.th_task_state)); 3117 } 3118 3119 // After threads exit the release, they will call sync, and then point to this 3120 // other task_team; make sure it is allocated and properly initialized. As 3121 // threads spin in the barrier release phase, they will continue to use the 3122 // previous task_team struct(above), until they receive the signal to stop 3123 // checking for tasks (they can't safely reference the kmp_team_t struct, 3124 // which could be reallocated by the master thread). No task teams are formed 3125 // for serialized teams. 3126 if (team->t.t_nproc > 1) { 3127 int other_team = 1 - this_thr->th.th_task_state; 3128 if (team->t.t_task_team[other_team] == NULL) { // setup other team as well 3129 team->t.t_task_team[other_team] = 3130 __kmp_allocate_task_team(this_thr, team); 3131 KA_TRACE(20, ("__kmp_task_team_setup: Master T#%d created second new " 3132 "task_team %p for team %d at parity=%d\n", 3133 __kmp_gtid_from_thread(this_thr), 3134 team->t.t_task_team[other_team], 3135 ((team != NULL) ? team->t.t_id : -1), other_team)); 3136 } else { // Leave the old task team struct in place for the upcoming region; 3137 // adjust as needed 3138 kmp_task_team_t *task_team = team->t.t_task_team[other_team]; 3139 if (!task_team->tt.tt_active || 3140 team->t.t_nproc != task_team->tt.tt_nproc) { 3141 TCW_4(task_team->tt.tt_nproc, team->t.t_nproc); 3142 TCW_4(task_team->tt.tt_found_tasks, FALSE); 3143 #if OMP_45_ENABLED 3144 TCW_4(task_team->tt.tt_found_proxy_tasks, FALSE); 3145 #endif 3146 TCW_4(task_team->tt.tt_unfinished_threads, team->t.t_nproc); 3147 TCW_4(task_team->tt.tt_active, TRUE); 3148 } 3149 // if team size has changed, the first thread to enable tasking will 3150 // realloc threads_data if necessary 3151 KA_TRACE(20, ("__kmp_task_team_setup: Master T#%d reset next task_team " 3152 "%p for team %d at parity=%d\n", 3153 __kmp_gtid_from_thread(this_thr), 3154 team->t.t_task_team[other_team], 3155 ((team != NULL) ? team->t.t_id : -1), other_team)); 3156 } 3157 } 3158 } 3159 3160 // __kmp_task_team_sync: Propagation of task team data from team to threads 3161 // which happens just after the release phase of a team barrier. This may be 3162 // called by any thread, but only for teams with # threads > 1. 3163 void __kmp_task_team_sync(kmp_info_t *this_thr, kmp_team_t *team) { 3164 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 3165 3166 // Toggle the th_task_state field, to switch which task_team this thread 3167 // refers to 3168 this_thr->th.th_task_state = 1 - this_thr->th.th_task_state; 3169 // It is now safe to propagate the task team pointer from the team struct to 3170 // the current thread. 3171 TCW_PTR(this_thr->th.th_task_team, 3172 team->t.t_task_team[this_thr->th.th_task_state]); 3173 KA_TRACE(20, 3174 ("__kmp_task_team_sync: Thread T#%d task team switched to task_team " 3175 "%p from Team #%d (parity=%d)\n", 3176 __kmp_gtid_from_thread(this_thr), this_thr->th.th_task_team, 3177 ((team != NULL) ? team->t.t_id : -1), this_thr->th.th_task_state)); 3178 } 3179 3180 // __kmp_task_team_wait: Master thread waits for outstanding tasks after the 3181 // barrier gather phase. Only called by master thread if #threads in team > 1 or 3182 // if proxy tasks were created. 3183 // 3184 // wait is a flag that defaults to 1 (see kmp.h), but waiting can be turned off 3185 // by passing in 0 optionally as the last argument. When wait is zero, master 3186 // thread does not wait for unfinished_threads to reach 0. 3187 void __kmp_task_team_wait( 3188 kmp_info_t *this_thr, 3189 kmp_team_t *team USE_ITT_BUILD_ARG(void *itt_sync_obj), int wait) { 3190 kmp_task_team_t *task_team = team->t.t_task_team[this_thr->th.th_task_state]; 3191 3192 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 3193 KMP_DEBUG_ASSERT(task_team == this_thr->th.th_task_team); 3194 3195 if ((task_team != NULL) && KMP_TASKING_ENABLED(task_team)) { 3196 if (wait) { 3197 KA_TRACE(20, ("__kmp_task_team_wait: Master T#%d waiting for all tasks " 3198 "(for unfinished_threads to reach 0) on task_team = %p\n", 3199 __kmp_gtid_from_thread(this_thr), task_team)); 3200 // Worker threads may have dropped through to release phase, but could 3201 // still be executing tasks. Wait here for tasks to complete. To avoid 3202 // memory contention, only master thread checks termination condition. 3203 kmp_flag_32 flag( 3204 RCAST(volatile kmp_uint32 *, &task_team->tt.tt_unfinished_threads), 3205 0U); 3206 flag.wait(this_thr, TRUE USE_ITT_BUILD_ARG(itt_sync_obj)); 3207 } 3208 // Deactivate the old task team, so that the worker threads will stop 3209 // referencing it while spinning. 3210 KA_TRACE( 3211 20, 3212 ("__kmp_task_team_wait: Master T#%d deactivating task_team %p: " 3213 "setting active to false, setting local and team's pointer to NULL\n", 3214 __kmp_gtid_from_thread(this_thr), task_team)); 3215 #if OMP_45_ENABLED 3216 KMP_DEBUG_ASSERT(task_team->tt.tt_nproc > 1 || 3217 task_team->tt.tt_found_proxy_tasks == TRUE); 3218 TCW_SYNC_4(task_team->tt.tt_found_proxy_tasks, FALSE); 3219 #else 3220 KMP_DEBUG_ASSERT(task_team->tt.tt_nproc > 1); 3221 #endif 3222 KMP_CHECK_UPDATE(task_team->tt.tt_untied_task_encountered, 0); 3223 TCW_SYNC_4(task_team->tt.tt_active, FALSE); 3224 KMP_MB(); 3225 3226 TCW_PTR(this_thr->th.th_task_team, NULL); 3227 } 3228 } 3229 3230 // __kmp_tasking_barrier: 3231 // This routine may only called when __kmp_tasking_mode == tskm_extra_barrier. 3232 // Internal function to execute all tasks prior to a regular barrier or a join 3233 // barrier. It is a full barrier itself, which unfortunately turns regular 3234 // barriers into double barriers and join barriers into 1 1/2 barriers. 3235 void __kmp_tasking_barrier(kmp_team_t *team, kmp_info_t *thread, int gtid) { 3236 volatile kmp_uint32 *spin = RCAST( 3237 volatile kmp_uint32 *, 3238 &team->t.t_task_team[thread->th.th_task_state]->tt.tt_unfinished_threads); 3239 int flag = FALSE; 3240 KMP_DEBUG_ASSERT(__kmp_tasking_mode == tskm_extra_barrier); 3241 3242 #if USE_ITT_BUILD 3243 KMP_FSYNC_SPIN_INIT(spin, (kmp_uint32 *)NULL); 3244 #endif /* USE_ITT_BUILD */ 3245 kmp_flag_32 spin_flag(spin, 0U); 3246 while (!spin_flag.execute_tasks(thread, gtid, TRUE, 3247 &flag USE_ITT_BUILD_ARG(NULL), 0)) { 3248 #if USE_ITT_BUILD 3249 // TODO: What about itt_sync_obj?? 3250 KMP_FSYNC_SPIN_PREPARE(CCAST(kmp_uint32 *, spin)); 3251 #endif /* USE_ITT_BUILD */ 3252 3253 if (TCR_4(__kmp_global.g.g_done)) { 3254 if (__kmp_global.g.g_abort) 3255 __kmp_abort_thread(); 3256 break; 3257 } 3258 KMP_YIELD(TRUE); // GH: We always yield here 3259 } 3260 #if USE_ITT_BUILD 3261 KMP_FSYNC_SPIN_ACQUIRED(CCAST(kmp_uint32 *, spin)); 3262 #endif /* USE_ITT_BUILD */ 3263 } 3264 3265 #if OMP_45_ENABLED 3266 3267 // __kmp_give_task puts a task into a given thread queue if: 3268 // - the queue for that thread was created 3269 // - there's space in that queue 3270 // Because of this, __kmp_push_task needs to check if there's space after 3271 // getting the lock 3272 static bool __kmp_give_task(kmp_info_t *thread, kmp_int32 tid, kmp_task_t *task, 3273 kmp_int32 pass) { 3274 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3275 kmp_task_team_t *task_team = taskdata->td_task_team; 3276 3277 KA_TRACE(20, ("__kmp_give_task: trying to give task %p to thread %d.\n", 3278 taskdata, tid)); 3279 3280 // If task_team is NULL something went really bad... 3281 KMP_DEBUG_ASSERT(task_team != NULL); 3282 3283 bool result = false; 3284 kmp_thread_data_t *thread_data = &task_team->tt.tt_threads_data[tid]; 3285 3286 if (thread_data->td.td_deque == NULL) { 3287 // There's no queue in this thread, go find another one 3288 // We're guaranteed that at least one thread has a queue 3289 KA_TRACE(30, 3290 ("__kmp_give_task: thread %d has no queue while giving task %p.\n", 3291 tid, taskdata)); 3292 return result; 3293 } 3294 3295 if (TCR_4(thread_data->td.td_deque_ntasks) >= 3296 TASK_DEQUE_SIZE(thread_data->td)) { 3297 KA_TRACE( 3298 30, 3299 ("__kmp_give_task: queue is full while giving task %p to thread %d.\n", 3300 taskdata, tid)); 3301 3302 // if this deque is bigger than the pass ratio give a chance to another 3303 // thread 3304 if (TASK_DEQUE_SIZE(thread_data->td) / INITIAL_TASK_DEQUE_SIZE >= pass) 3305 return result; 3306 3307 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 3308 __kmp_realloc_task_deque(thread, thread_data); 3309 3310 } else { 3311 3312 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 3313 3314 if (TCR_4(thread_data->td.td_deque_ntasks) >= 3315 TASK_DEQUE_SIZE(thread_data->td)) { 3316 KA_TRACE(30, ("__kmp_give_task: queue is full while giving task %p to " 3317 "thread %d.\n", 3318 taskdata, tid)); 3319 3320 // if this deque is bigger than the pass ratio give a chance to another 3321 // thread 3322 if (TASK_DEQUE_SIZE(thread_data->td) / INITIAL_TASK_DEQUE_SIZE >= pass) 3323 goto release_and_exit; 3324 3325 __kmp_realloc_task_deque(thread, thread_data); 3326 } 3327 } 3328 3329 // lock is held here, and there is space in the deque 3330 3331 thread_data->td.td_deque[thread_data->td.td_deque_tail] = taskdata; 3332 // Wrap index. 3333 thread_data->td.td_deque_tail = 3334 (thread_data->td.td_deque_tail + 1) & TASK_DEQUE_MASK(thread_data->td); 3335 TCW_4(thread_data->td.td_deque_ntasks, 3336 TCR_4(thread_data->td.td_deque_ntasks) + 1); 3337 3338 result = true; 3339 KA_TRACE(30, ("__kmp_give_task: successfully gave task %p to thread %d.\n", 3340 taskdata, tid)); 3341 3342 release_and_exit: 3343 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 3344 3345 return result; 3346 } 3347 3348 /* The finish of the proxy tasks is divided in two pieces: 3349 - the top half is the one that can be done from a thread outside the team 3350 - the bottom half must be run from a them within the team 3351 3352 In order to run the bottom half the task gets queued back into one of the 3353 threads of the team. Once the td_incomplete_child_task counter of the parent 3354 is decremented the threads can leave the barriers. So, the bottom half needs 3355 to be queued before the counter is decremented. The top half is therefore 3356 divided in two parts: 3357 - things that can be run before queuing the bottom half 3358 - things that must be run after queuing the bottom half 3359 3360 This creates a second race as the bottom half can free the task before the 3361 second top half is executed. To avoid this we use the 3362 td_incomplete_child_task of the proxy task to synchronize the top and bottom 3363 half. */ 3364 static void __kmp_first_top_half_finish_proxy(kmp_taskdata_t *taskdata) { 3365 KMP_DEBUG_ASSERT(taskdata->td_flags.tasktype == TASK_EXPLICIT); 3366 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3367 KMP_DEBUG_ASSERT(taskdata->td_flags.complete == 0); 3368 KMP_DEBUG_ASSERT(taskdata->td_flags.freed == 0); 3369 3370 taskdata->td_flags.complete = 1; // mark the task as completed 3371 3372 if (taskdata->td_taskgroup) 3373 KMP_TEST_THEN_DEC32(&taskdata->td_taskgroup->count); 3374 3375 // Create an imaginary children for this task so the bottom half cannot 3376 // release the task before we have completed the second top half 3377 TCI_4(taskdata->td_incomplete_child_tasks); 3378 } 3379 3380 static void __kmp_second_top_half_finish_proxy(kmp_taskdata_t *taskdata) { 3381 kmp_int32 children = 0; 3382 3383 // Predecrement simulated by "- 1" calculation 3384 children = 3385 KMP_TEST_THEN_DEC32(&taskdata->td_parent->td_incomplete_child_tasks) - 1; 3386 KMP_DEBUG_ASSERT(children >= 0); 3387 3388 // Remove the imaginary children 3389 TCD_4(taskdata->td_incomplete_child_tasks); 3390 } 3391 3392 static void __kmp_bottom_half_finish_proxy(kmp_int32 gtid, kmp_task_t *ptask) { 3393 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(ptask); 3394 kmp_info_t *thread = __kmp_threads[gtid]; 3395 3396 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3397 KMP_DEBUG_ASSERT(taskdata->td_flags.complete == 3398 1); // top half must run before bottom half 3399 3400 // We need to wait to make sure the top half is finished 3401 // Spinning here should be ok as this should happen quickly 3402 while (TCR_4(taskdata->td_incomplete_child_tasks) > 0) 3403 ; 3404 3405 __kmp_release_deps(gtid, taskdata); 3406 __kmp_free_task_and_ancestors(gtid, taskdata, thread); 3407 } 3408 3409 /*! 3410 @ingroup TASKING 3411 @param gtid Global Thread ID of encountering thread 3412 @param ptask Task which execution is completed 3413 3414 Execute the completation of a proxy task from a thread of that is part of the 3415 team. Run first and bottom halves directly. 3416 */ 3417 void __kmpc_proxy_task_completed(kmp_int32 gtid, kmp_task_t *ptask) { 3418 KMP_DEBUG_ASSERT(ptask != NULL); 3419 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(ptask); 3420 KA_TRACE( 3421 10, ("__kmp_proxy_task_completed(enter): T#%d proxy task %p completing\n", 3422 gtid, taskdata)); 3423 3424 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3425 3426 __kmp_first_top_half_finish_proxy(taskdata); 3427 __kmp_second_top_half_finish_proxy(taskdata); 3428 __kmp_bottom_half_finish_proxy(gtid, ptask); 3429 3430 KA_TRACE(10, 3431 ("__kmp_proxy_task_completed(exit): T#%d proxy task %p completing\n", 3432 gtid, taskdata)); 3433 } 3434 3435 /*! 3436 @ingroup TASKING 3437 @param ptask Task which execution is completed 3438 3439 Execute the completation of a proxy task from a thread that could not belong to 3440 the team. 3441 */ 3442 void __kmpc_proxy_task_completed_ooo(kmp_task_t *ptask) { 3443 KMP_DEBUG_ASSERT(ptask != NULL); 3444 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(ptask); 3445 3446 KA_TRACE( 3447 10, 3448 ("__kmp_proxy_task_completed_ooo(enter): proxy task completing ooo %p\n", 3449 taskdata)); 3450 3451 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3452 3453 __kmp_first_top_half_finish_proxy(taskdata); 3454 3455 // Enqueue task to complete bottom half completion from a thread within the 3456 // corresponding team 3457 kmp_team_t *team = taskdata->td_team; 3458 kmp_int32 nthreads = team->t.t_nproc; 3459 kmp_info_t *thread; 3460 3461 // This should be similar to start_k = __kmp_get_random( thread ) % nthreads 3462 // but we cannot use __kmp_get_random here 3463 kmp_int32 start_k = 0; 3464 kmp_int32 pass = 1; 3465 kmp_int32 k = start_k; 3466 3467 do { 3468 // For now we're just linearly trying to find a thread 3469 thread = team->t.t_threads[k]; 3470 k = (k + 1) % nthreads; 3471 3472 // we did a full pass through all the threads 3473 if (k == start_k) 3474 pass = pass << 1; 3475 3476 } while (!__kmp_give_task(thread, k, ptask, pass)); 3477 3478 __kmp_second_top_half_finish_proxy(taskdata); 3479 3480 KA_TRACE( 3481 10, 3482 ("__kmp_proxy_task_completed_ooo(exit): proxy task completing ooo %p\n", 3483 taskdata)); 3484 } 3485 3486 // __kmp_task_dup_alloc: Allocate the taskdata and make a copy of source task 3487 // for taskloop 3488 // 3489 // thread: allocating thread 3490 // task_src: pointer to source task to be duplicated 3491 // returns: a pointer to the allocated kmp_task_t structure (task). 3492 kmp_task_t *__kmp_task_dup_alloc(kmp_info_t *thread, kmp_task_t *task_src) { 3493 kmp_task_t *task; 3494 kmp_taskdata_t *taskdata; 3495 kmp_taskdata_t *taskdata_src; 3496 kmp_taskdata_t *parent_task = thread->th.th_current_task; 3497 size_t shareds_offset; 3498 size_t task_size; 3499 3500 KA_TRACE(10, ("__kmp_task_dup_alloc(enter): Th %p, source task %p\n", thread, 3501 task_src)); 3502 taskdata_src = KMP_TASK_TO_TASKDATA(task_src); 3503 KMP_DEBUG_ASSERT(taskdata_src->td_flags.proxy == 3504 TASK_FULL); // it should not be proxy task 3505 KMP_DEBUG_ASSERT(taskdata_src->td_flags.tasktype == TASK_EXPLICIT); 3506 task_size = taskdata_src->td_size_alloc; 3507 3508 // Allocate a kmp_taskdata_t block and a kmp_task_t block. 3509 KA_TRACE(30, ("__kmp_task_dup_alloc: Th %p, malloc size %ld\n", thread, 3510 task_size)); 3511 #if USE_FAST_MEMORY 3512 taskdata = (kmp_taskdata_t *)__kmp_fast_allocate(thread, task_size); 3513 #else 3514 taskdata = (kmp_taskdata_t *)__kmp_thread_malloc(thread, task_size); 3515 #endif /* USE_FAST_MEMORY */ 3516 KMP_MEMCPY(taskdata, taskdata_src, task_size); 3517 3518 task = KMP_TASKDATA_TO_TASK(taskdata); 3519 3520 // Initialize new task (only specific fields not affected by memcpy) 3521 taskdata->td_task_id = KMP_GEN_TASK_ID(); 3522 if (task->shareds != NULL) { // need setup shareds pointer 3523 shareds_offset = (char *)task_src->shareds - (char *)taskdata_src; 3524 task->shareds = &((char *)taskdata)[shareds_offset]; 3525 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task->shareds) & (sizeof(void *) - 1)) == 3526 0); 3527 } 3528 taskdata->td_alloc_thread = thread; 3529 taskdata->td_parent = parent_task; 3530 taskdata->td_taskgroup = 3531 parent_task 3532 ->td_taskgroup; // task inherits the taskgroup from the parent task 3533 3534 // Only need to keep track of child task counts if team parallel and tasking 3535 // not serialized 3536 if (!(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser)) { 3537 KMP_TEST_THEN_INC32(&parent_task->td_incomplete_child_tasks); 3538 if (parent_task->td_taskgroup) 3539 KMP_TEST_THEN_INC32(&parent_task->td_taskgroup->count); 3540 // Only need to keep track of allocated child tasks for explicit tasks since 3541 // implicit not deallocated 3542 if (taskdata->td_parent->td_flags.tasktype == TASK_EXPLICIT) 3543 KMP_TEST_THEN_INC32(&taskdata->td_parent->td_allocated_child_tasks); 3544 } 3545 3546 KA_TRACE(20, 3547 ("__kmp_task_dup_alloc(exit): Th %p, created task %p, parent=%p\n", 3548 thread, taskdata, taskdata->td_parent)); 3549 #if OMPT_SUPPORT 3550 if (UNLIKELY(ompt_enabled.enabled)) 3551 __ompt_task_init(taskdata, thread->th.th_info.ds.ds_gtid); 3552 #endif 3553 return task; 3554 } 3555 3556 // Routine optionally generated by the compiler for setting the lastprivate flag 3557 // and calling needed constructors for private/firstprivate objects 3558 // (used to form taskloop tasks from pattern task) 3559 // Parameters: dest task, src task, lastprivate flag. 3560 typedef void (*p_task_dup_t)(kmp_task_t *, kmp_task_t *, kmp_int32); 3561 3562 // __kmp_taskloop_linear: Start tasks of the taskloop linearly 3563 // 3564 // loc Source location information 3565 // gtid Global thread ID 3566 // task Pattern task, exposes the loop iteration range 3567 // lb Pointer to loop lower bound in task structure 3568 // ub Pointer to loop upper bound in task structure 3569 // st Loop stride 3570 // ub_glob Global upper bound (used for lastprivate check) 3571 // num_tasks Number of tasks to execute 3572 // grainsize Number of loop iterations per task 3573 // extras Number of chunks with grainsize+1 iterations 3574 // tc Iterations count 3575 // task_dup Tasks duplication routine 3576 void __kmp_taskloop_linear(ident_t *loc, int gtid, kmp_task_t *task, 3577 kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, 3578 kmp_uint64 ub_glob, kmp_uint64 num_tasks, 3579 kmp_uint64 grainsize, kmp_uint64 extras, 3580 kmp_uint64 tc, void *task_dup) { 3581 KMP_COUNT_BLOCK(OMP_TASKLOOP); 3582 KMP_TIME_PARTITIONED_BLOCK(OMP_taskloop_scheduling); 3583 p_task_dup_t ptask_dup = (p_task_dup_t)task_dup; 3584 kmp_uint64 lower = *lb; // compiler provides global bounds here 3585 kmp_uint64 upper = *ub; 3586 kmp_uint64 i; 3587 kmp_info_t *thread = __kmp_threads[gtid]; 3588 kmp_taskdata_t *current_task = thread->th.th_current_task; 3589 kmp_task_t *next_task; 3590 kmp_int32 lastpriv = 0; 3591 size_t lower_offset = 3592 (char *)lb - (char *)task; // remember offset of lb in the task structure 3593 size_t upper_offset = 3594 (char *)ub - (char *)task; // remember offset of ub in the task structure 3595 3596 KMP_DEBUG_ASSERT(tc == num_tasks * grainsize + extras); 3597 KMP_DEBUG_ASSERT(num_tasks > extras); 3598 KMP_DEBUG_ASSERT(num_tasks > 0); 3599 KA_TRACE(20, ("__kmp_taskloop_linear: T#%d: %lld tasks, grainsize %lld, " 3600 "extras %lld, i=%lld,%lld(%d)%lld, dup %p\n", 3601 gtid, num_tasks, grainsize, extras, lower, upper, ub_glob, st, 3602 task_dup)); 3603 3604 // Launch num_tasks tasks, assign grainsize iterations each task 3605 for (i = 0; i < num_tasks; ++i) { 3606 kmp_uint64 chunk_minus_1; 3607 if (extras == 0) { 3608 chunk_minus_1 = grainsize - 1; 3609 } else { 3610 chunk_minus_1 = grainsize; 3611 --extras; // first extras iterations get bigger chunk (grainsize+1) 3612 } 3613 upper = lower + st * chunk_minus_1; 3614 if (i == num_tasks - 1) { 3615 // schedule the last task, set lastprivate flag if needed 3616 if (st == 1) { // most common case 3617 KMP_DEBUG_ASSERT(upper == *ub); 3618 if (upper == ub_glob) 3619 lastpriv = 1; 3620 } else if (st > 0) { // positive loop stride 3621 KMP_DEBUG_ASSERT((kmp_uint64)st > *ub - upper); 3622 if ((kmp_uint64)st > ub_glob - upper) 3623 lastpriv = 1; 3624 } else { // negative loop stride 3625 KMP_DEBUG_ASSERT(upper + st < *ub); 3626 if (upper - ub_glob < (kmp_uint64)(-st)) 3627 lastpriv = 1; 3628 } 3629 } 3630 next_task = __kmp_task_dup_alloc(thread, task); // allocate new task 3631 // adjust task-specific bounds 3632 *(kmp_uint64 *)((char *)next_task + lower_offset) = lower; 3633 *(kmp_uint64 *)((char *)next_task + upper_offset) = upper; 3634 if (ptask_dup != NULL) // set lastprivate flag, construct fistprivates, etc. 3635 ptask_dup(next_task, task, lastpriv); 3636 KA_TRACE(40, ("__kmp_taskloop_linear: T#%d; task %p: lower %lld, " 3637 "upper %lld (offsets %p %p)\n", 3638 gtid, next_task, lower, upper, lower_offset, upper_offset)); 3639 __kmp_omp_task(gtid, next_task, true); // schedule new task 3640 lower = upper + st; // adjust lower bound for the next iteration 3641 } 3642 // free the pattern task and exit 3643 __kmp_task_start(gtid, task, current_task); // make internal bookkeeping 3644 // do not execute the pattern task, just do internal bookkeeping 3645 __kmp_task_finish(gtid, task, current_task); 3646 } 3647 3648 // Structure to keep taskloop parameters for auxiliary task 3649 // kept in the shareds of the task structure. 3650 typedef struct __taskloop_params { 3651 kmp_task_t *task; 3652 kmp_uint64 *lb; 3653 kmp_uint64 *ub; 3654 void *task_dup; 3655 kmp_int64 st; 3656 kmp_uint64 ub_glob; 3657 kmp_uint64 num_tasks; 3658 kmp_uint64 grainsize; 3659 kmp_uint64 extras; 3660 kmp_uint64 tc; 3661 kmp_uint64 num_t_min; 3662 } __taskloop_params_t; 3663 3664 void __kmp_taskloop_recur(ident_t *, int, kmp_task_t *, kmp_uint64 *, 3665 kmp_uint64 *, kmp_int64, kmp_uint64, kmp_uint64, 3666 kmp_uint64, kmp_uint64, kmp_uint64, kmp_uint64, 3667 void *); 3668 3669 // Execute part of the the taskloop submitted as a task. 3670 int __kmp_taskloop_task(int gtid, void *ptask) { 3671 __taskloop_params_t *p = 3672 (__taskloop_params_t *)((kmp_task_t *)ptask)->shareds; 3673 kmp_task_t *task = p->task; 3674 kmp_uint64 *lb = p->lb; 3675 kmp_uint64 *ub = p->ub; 3676 void *task_dup = p->task_dup; 3677 // p_task_dup_t ptask_dup = (p_task_dup_t)task_dup; 3678 kmp_int64 st = p->st; 3679 kmp_uint64 ub_glob = p->ub_glob; 3680 kmp_uint64 num_tasks = p->num_tasks; 3681 kmp_uint64 grainsize = p->grainsize; 3682 kmp_uint64 extras = p->extras; 3683 kmp_uint64 tc = p->tc; 3684 kmp_uint64 num_t_min = p->num_t_min; 3685 #if KMP_DEBUG 3686 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3687 KMP_DEBUG_ASSERT(task != NULL); 3688 KA_TRACE(20, ("__kmp_taskloop_task: T#%d, task %p: %lld tasks, grainsize" 3689 " %lld, extras %lld, i=%lld,%lld(%d), dup %p\n", 3690 gtid, taskdata, num_tasks, grainsize, extras, *lb, *ub, st, 3691 task_dup)); 3692 #endif 3693 KMP_DEBUG_ASSERT(num_tasks * 2 + 1 > num_t_min); 3694 if (num_tasks > num_t_min) 3695 __kmp_taskloop_recur(NULL, gtid, task, lb, ub, st, ub_glob, num_tasks, 3696 grainsize, extras, tc, num_t_min, task_dup); 3697 else 3698 __kmp_taskloop_linear(NULL, gtid, task, lb, ub, st, ub_glob, num_tasks, 3699 grainsize, extras, tc, task_dup); 3700 3701 KA_TRACE(40, ("__kmp_taskloop_task(exit): T#%d\n", gtid)); 3702 return 0; 3703 } 3704 3705 // Schedule part of the the taskloop as a task, 3706 // execute the rest of the the taskloop. 3707 // 3708 // loc Source location information 3709 // gtid Global thread ID 3710 // task Pattern task, exposes the loop iteration range 3711 // lb Pointer to loop lower bound in task structure 3712 // ub Pointer to loop upper bound in task structure 3713 // st Loop stride 3714 // ub_glob Global upper bound (used for lastprivate check) 3715 // num_tasks Number of tasks to execute 3716 // grainsize Number of loop iterations per task 3717 // extras Number of chunks with grainsize+1 iterations 3718 // tc Iterations count 3719 // num_t_min Threashold to launch tasks recursively 3720 // task_dup Tasks duplication routine 3721 void __kmp_taskloop_recur(ident_t *loc, int gtid, kmp_task_t *task, 3722 kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, 3723 kmp_uint64 ub_glob, kmp_uint64 num_tasks, 3724 kmp_uint64 grainsize, kmp_uint64 extras, 3725 kmp_uint64 tc, kmp_uint64 num_t_min, void *task_dup) { 3726 #if KMP_DEBUG 3727 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3728 KMP_DEBUG_ASSERT(task != NULL); 3729 KMP_DEBUG_ASSERT(num_tasks > num_t_min); 3730 KA_TRACE(20, ("__kmp_taskloop_recur: T#%d, task %p: %lld tasks, grainsize" 3731 " %lld, extras %lld, i=%lld,%lld(%d), dup %p\n", 3732 gtid, taskdata, num_tasks, grainsize, extras, *lb, *ub, st, 3733 task_dup)); 3734 #endif 3735 p_task_dup_t ptask_dup = (p_task_dup_t)task_dup; 3736 kmp_uint64 lower = *lb; 3737 kmp_uint64 upper = *ub; 3738 kmp_info_t *thread = __kmp_threads[gtid]; 3739 // kmp_taskdata_t *current_task = thread->th.th_current_task; 3740 kmp_task_t *next_task; 3741 kmp_int32 lastpriv = 0; 3742 size_t lower_offset = 3743 (char *)lb - (char *)task; // remember offset of lb in the task structure 3744 size_t upper_offset = 3745 (char *)ub - (char *)task; // remember offset of ub in the task structure 3746 3747 KMP_DEBUG_ASSERT(tc == num_tasks * grainsize + extras); 3748 KMP_DEBUG_ASSERT(num_tasks > extras); 3749 KMP_DEBUG_ASSERT(num_tasks > 0); 3750 3751 // split the loop in two halves 3752 kmp_uint64 lb1, ub0, tc0, tc1, ext0, ext1; 3753 kmp_uint64 gr_size0 = grainsize; 3754 kmp_uint64 n_tsk0 = num_tasks >> 1; // num_tasks/2 to execute 3755 kmp_uint64 n_tsk1 = num_tasks - n_tsk0; // to schedule as a task 3756 if (n_tsk0 <= extras) { 3757 gr_size0++; // integrate extras into grainsize 3758 ext0 = 0; // no extra iters in 1st half 3759 ext1 = extras - n_tsk0; // remaining extras 3760 tc0 = gr_size0 * n_tsk0; 3761 tc1 = tc - tc0; 3762 } else { // n_tsk0 > extras 3763 ext1 = 0; // no extra iters in 2nd half 3764 ext0 = extras; 3765 tc1 = grainsize * n_tsk1; 3766 tc0 = tc - tc1; 3767 } 3768 ub0 = lower + st * (tc0 - 1); 3769 lb1 = ub0 + st; 3770 3771 // create pattern task for 2nd half of the loop 3772 next_task = __kmp_task_dup_alloc(thread, task); // duplicate the task 3773 // adjust lower bound (upper bound is not changed) for the 2nd half 3774 *(kmp_uint64 *)((char *)next_task + lower_offset) = lb1; 3775 if (ptask_dup != NULL) // construct fistprivates, etc. 3776 ptask_dup(next_task, task, 0); 3777 *ub = ub0; // adjust upper bound for the 1st half 3778 3779 // create auxiliary task for 2nd half of the loop 3780 kmp_task_t *new_task = 3781 __kmpc_omp_task_alloc(loc, gtid, 1, 3 * sizeof(void *), 3782 sizeof(__taskloop_params_t), &__kmp_taskloop_task); 3783 __taskloop_params_t *p = (__taskloop_params_t *)new_task->shareds; 3784 p->task = next_task; 3785 p->lb = (kmp_uint64 *)((char *)next_task + lower_offset); 3786 p->ub = (kmp_uint64 *)((char *)next_task + upper_offset); 3787 p->task_dup = task_dup; 3788 p->st = st; 3789 p->ub_glob = ub_glob; 3790 p->num_tasks = n_tsk1; 3791 p->grainsize = grainsize; 3792 p->extras = ext1; 3793 p->tc = tc1; 3794 p->num_t_min = num_t_min; 3795 __kmp_omp_task(gtid, new_task, true); // schedule new task 3796 3797 // execute the 1st half of current subrange 3798 if (n_tsk0 > num_t_min) 3799 __kmp_taskloop_recur(loc, gtid, task, lb, ub, st, ub_glob, n_tsk0, gr_size0, 3800 ext0, tc0, num_t_min, task_dup); 3801 else 3802 __kmp_taskloop_linear(loc, gtid, task, lb, ub, st, ub_glob, n_tsk0, 3803 gr_size0, ext0, tc0, task_dup); 3804 3805 KA_TRACE(40, ("__kmpc_taskloop_recur(exit): T#%d\n", gtid)); 3806 } 3807 3808 /*! 3809 @ingroup TASKING 3810 @param loc Source location information 3811 @param gtid Global thread ID 3812 @param task Task structure 3813 @param if_val Value of the if clause 3814 @param lb Pointer to loop lower bound in task structure 3815 @param ub Pointer to loop upper bound in task structure 3816 @param st Loop stride 3817 @param nogroup Flag, 1 if nogroup clause specified, 0 otherwise 3818 @param sched Schedule specified 0/1/2 for none/grainsize/num_tasks 3819 @param grainsize Schedule value if specified 3820 @param task_dup Tasks duplication routine 3821 3822 Execute the taskloop construct. 3823 */ 3824 void __kmpc_taskloop(ident_t *loc, int gtid, kmp_task_t *task, int if_val, 3825 kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, int nogroup, 3826 int sched, kmp_uint64 grainsize, void *task_dup) { 3827 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3828 KMP_DEBUG_ASSERT(task != NULL); 3829 3830 KA_TRACE(20, ("__kmpc_taskloop: T#%d, task %p, lb %lld, ub %lld, st %lld, " 3831 "grain %llu(%d), dup %p\n", 3832 gtid, taskdata, *lb, *ub, st, grainsize, sched, task_dup)); 3833 3834 #if OMPT_SUPPORT && OMPT_OPTIONAL 3835 ompt_team_info_t *team_info = __ompt_get_teaminfo(0, NULL); 3836 ompt_task_info_t *task_info = __ompt_get_task_info_object(0); 3837 if (ompt_enabled.ompt_callback_work) { 3838 ompt_callbacks.ompt_callback(ompt_callback_work)( 3839 ompt_work_taskloop, ompt_scope_begin, &(team_info->parallel_data), 3840 &(task_info->task_data), 0, OMPT_GET_RETURN_ADDRESS(0)); 3841 } 3842 #endif 3843 3844 if (nogroup == 0) { 3845 #if OMPT_SUPPORT && OMPT_OPTIONAL 3846 OMPT_STORE_RETURN_ADDRESS(gtid); 3847 #endif 3848 __kmpc_taskgroup(loc, gtid); 3849 } 3850 3851 // ========================================================================= 3852 // calculate loop parameters 3853 kmp_uint64 tc; 3854 kmp_uint64 lower = *lb; // compiler provides global bounds here 3855 kmp_uint64 upper = *ub; 3856 kmp_uint64 ub_glob = upper; // global upper used to calc lastprivate flag 3857 kmp_uint64 num_tasks = 0, extras = 0; 3858 kmp_uint64 num_tasks_min = __kmp_taskloop_min_tasks; 3859 kmp_info_t *thread = __kmp_threads[gtid]; 3860 kmp_taskdata_t *current_task = thread->th.th_current_task; 3861 3862 // compute trip count 3863 if (st == 1) { // most common case 3864 tc = upper - lower + 1; 3865 } else if (st < 0) { 3866 tc = (lower - upper) / (-st) + 1; 3867 } else { // st > 0 3868 tc = (upper - lower) / st + 1; 3869 } 3870 if (tc == 0) { 3871 KA_TRACE(20, ("__kmpc_taskloop(exit): T#%d zero-trip loop\n", gtid)); 3872 // free the pattern task and exit 3873 __kmp_task_start(gtid, task, current_task); 3874 // do not execute anything for zero-trip loop 3875 __kmp_task_finish(gtid, task, current_task); 3876 return; 3877 } 3878 if (num_tasks_min == 0) 3879 // TODO: can we choose better default heuristic? 3880 num_tasks_min = 3881 KMP_MIN(thread->th.th_team_nproc * 10, INITIAL_TASK_DEQUE_SIZE); 3882 3883 // compute num_tasks/grainsize based on the input provided 3884 switch (sched) { 3885 case 0: // no schedule clause specified, we can choose the default 3886 // let's try to schedule (team_size*10) tasks 3887 grainsize = thread->th.th_team_nproc * 10; 3888 case 2: // num_tasks provided 3889 if (grainsize > tc) { 3890 num_tasks = tc; // too big num_tasks requested, adjust values 3891 grainsize = 1; 3892 extras = 0; 3893 } else { 3894 num_tasks = grainsize; 3895 grainsize = tc / num_tasks; 3896 extras = tc % num_tasks; 3897 } 3898 break; 3899 case 1: // grainsize provided 3900 if (grainsize > tc) { 3901 num_tasks = 1; // too big grainsize requested, adjust values 3902 grainsize = tc; 3903 extras = 0; 3904 } else { 3905 num_tasks = tc / grainsize; 3906 // adjust grainsize for balanced distribution of iterations 3907 grainsize = tc / num_tasks; 3908 extras = tc % num_tasks; 3909 } 3910 break; 3911 default: 3912 KMP_ASSERT2(0, "unknown scheduling of taskloop"); 3913 } 3914 KMP_DEBUG_ASSERT(tc == num_tasks * grainsize + extras); 3915 KMP_DEBUG_ASSERT(num_tasks > extras); 3916 KMP_DEBUG_ASSERT(num_tasks > 0); 3917 // ========================================================================= 3918 3919 // check if clause value first 3920 if (if_val == 0) { // if(0) specified, mark task as serial 3921 taskdata->td_flags.task_serial = 1; 3922 taskdata->td_flags.tiedness = TASK_TIED; // AC: serial task cannot be untied 3923 #if OMPT_SUPPORT && OMPT_OPTIONAL 3924 OMPT_STORE_RETURN_ADDRESS(gtid); 3925 #endif 3926 // always start serial tasks linearly 3927 __kmp_taskloop_linear(loc, gtid, task, lb, ub, st, ub_glob, num_tasks, 3928 grainsize, extras, tc, task_dup); 3929 } else if (num_tasks > num_tasks_min) { 3930 KA_TRACE(20, ("__kmpc_taskloop: T#%d, go recursive: tc %llu, #tasks %llu" 3931 "(%lld), grain %llu, extras %llu\n", 3932 gtid, tc, num_tasks, num_tasks_min, grainsize, extras)); 3933 #if OMPT_SUPPORT && OMPT_OPTIONAL 3934 OMPT_STORE_RETURN_ADDRESS(gtid); 3935 #endif 3936 __kmp_taskloop_recur(loc, gtid, task, lb, ub, st, ub_glob, num_tasks, 3937 grainsize, extras, tc, num_tasks_min, task_dup); 3938 } else { 3939 KA_TRACE(20, ("__kmpc_taskloop: T#%d, go linear: tc %llu, #tasks %llu" 3940 "(%lld), grain %llu, extras %llu\n", 3941 gtid, tc, num_tasks, num_tasks_min, grainsize, extras)); 3942 #if OMPT_SUPPORT && OMPT_OPTIONAL 3943 OMPT_STORE_RETURN_ADDRESS(gtid); 3944 #endif 3945 __kmp_taskloop_linear(loc, gtid, task, lb, ub, st, ub_glob, num_tasks, 3946 grainsize, extras, tc, task_dup); 3947 } 3948 3949 if (nogroup == 0) { 3950 #if OMPT_SUPPORT && OMPT_OPTIONAL 3951 OMPT_STORE_RETURN_ADDRESS(gtid); 3952 #endif 3953 __kmpc_end_taskgroup(loc, gtid); 3954 } 3955 #if OMPT_SUPPORT && OMPT_OPTIONAL 3956 if (ompt_enabled.ompt_callback_work) { 3957 ompt_callbacks.ompt_callback(ompt_callback_work)( 3958 ompt_work_taskloop, ompt_scope_end, &(team_info->parallel_data), 3959 &(task_info->task_data), 0, OMPT_GET_RETURN_ADDRESS(0)); 3960 } 3961 #endif 3962 KA_TRACE(20, ("__kmpc_taskloop(exit): T#%d\n", gtid)); 3963 } 3964 3965 #endif 3966