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->td_dephash) 988 __kmp_dephash_free(thread, task->td_dephash); 989 task->td_dephash = NULL; 990 } 991 992 // Round up a size to a power of two specified by val: Used to insert padding 993 // between structures co-allocated using a single malloc() call 994 static size_t __kmp_round_up_to_val(size_t size, size_t val) { 995 if (size & (val - 1)) { 996 size &= ~(val - 1); 997 if (size <= KMP_SIZE_T_MAX - val) { 998 size += val; // Round up if there is no overflow. 999 } 1000 } 1001 return size; 1002 } // __kmp_round_up_to_va 1003 1004 // __kmp_task_alloc: Allocate the taskdata and task data structures for a task 1005 // 1006 // loc_ref: source location information 1007 // gtid: global thread number. 1008 // flags: include tiedness & task type (explicit vs. implicit) of the ''new'' 1009 // task encountered. Converted from kmp_int32 to kmp_tasking_flags_t in routine. 1010 // sizeof_kmp_task_t: Size in bytes of kmp_task_t data structure including 1011 // private vars accessed in task. 1012 // sizeof_shareds: Size in bytes of array of pointers to shared vars accessed 1013 // in task. 1014 // task_entry: Pointer to task code entry point generated by compiler. 1015 // returns: a pointer to the allocated kmp_task_t structure (task). 1016 kmp_task_t *__kmp_task_alloc(ident_t *loc_ref, kmp_int32 gtid, 1017 kmp_tasking_flags_t *flags, 1018 size_t sizeof_kmp_task_t, size_t sizeof_shareds, 1019 kmp_routine_entry_t task_entry) { 1020 kmp_task_t *task; 1021 kmp_taskdata_t *taskdata; 1022 kmp_info_t *thread = __kmp_threads[gtid]; 1023 kmp_team_t *team = thread->th.th_team; 1024 kmp_taskdata_t *parent_task = thread->th.th_current_task; 1025 size_t shareds_offset; 1026 1027 KA_TRACE(10, ("__kmp_task_alloc(enter): T#%d loc=%p, flags=(0x%x) " 1028 "sizeof_task=%ld sizeof_shared=%ld entry=%p\n", 1029 gtid, loc_ref, *((kmp_int32 *)flags), sizeof_kmp_task_t, 1030 sizeof_shareds, task_entry)); 1031 1032 if (parent_task->td_flags.final) { 1033 if (flags->merged_if0) { 1034 } 1035 flags->final = 1; 1036 } 1037 if (flags->tiedness == TASK_UNTIED && !team->t.t_serialized) { 1038 // Untied task encountered causes the TSC algorithm to check entire deque of 1039 // the victim thread. If no untied task encountered, then checking the head 1040 // of the deque should be enough. 1041 KMP_CHECK_UPDATE(thread->th.th_task_team->tt.tt_untied_task_encountered, 1); 1042 } 1043 1044 #if OMP_45_ENABLED 1045 if (flags->proxy == TASK_PROXY) { 1046 flags->tiedness = TASK_UNTIED; 1047 flags->merged_if0 = 1; 1048 1049 /* are we running in a sequential parallel or tskm_immediate_exec... we need 1050 tasking support enabled */ 1051 if ((thread->th.th_task_team) == NULL) { 1052 /* This should only happen if the team is serialized 1053 setup a task team and propagate it to the thread */ 1054 KMP_DEBUG_ASSERT(team->t.t_serialized); 1055 KA_TRACE(30, 1056 ("T#%d creating task team in __kmp_task_alloc for proxy task\n", 1057 gtid)); 1058 __kmp_task_team_setup( 1059 thread, team, 1060 1); // 1 indicates setup the current team regardless of nthreads 1061 thread->th.th_task_team = team->t.t_task_team[thread->th.th_task_state]; 1062 } 1063 kmp_task_team_t *task_team = thread->th.th_task_team; 1064 1065 /* tasking must be enabled now as the task might not be pushed */ 1066 if (!KMP_TASKING_ENABLED(task_team)) { 1067 KA_TRACE( 1068 30, 1069 ("T#%d enabling tasking in __kmp_task_alloc for proxy task\n", gtid)); 1070 __kmp_enable_tasking(task_team, thread); 1071 kmp_int32 tid = thread->th.th_info.ds.ds_tid; 1072 kmp_thread_data_t *thread_data = &task_team->tt.tt_threads_data[tid]; 1073 // No lock needed since only owner can allocate 1074 if (thread_data->td.td_deque == NULL) { 1075 __kmp_alloc_task_deque(thread, thread_data); 1076 } 1077 } 1078 1079 if (task_team->tt.tt_found_proxy_tasks == FALSE) 1080 TCW_4(task_team->tt.tt_found_proxy_tasks, TRUE); 1081 } 1082 #endif 1083 1084 // Calculate shared structure offset including padding after kmp_task_t struct 1085 // to align pointers in shared struct 1086 shareds_offset = sizeof(kmp_taskdata_t) + sizeof_kmp_task_t; 1087 shareds_offset = __kmp_round_up_to_val(shareds_offset, sizeof(void *)); 1088 1089 // Allocate a kmp_taskdata_t block and a kmp_task_t block. 1090 KA_TRACE(30, ("__kmp_task_alloc: T#%d First malloc size: %ld\n", gtid, 1091 shareds_offset)); 1092 KA_TRACE(30, ("__kmp_task_alloc: T#%d Second malloc size: %ld\n", gtid, 1093 sizeof_shareds)); 1094 1095 // Avoid double allocation here by combining shareds with taskdata 1096 #if USE_FAST_MEMORY 1097 taskdata = (kmp_taskdata_t *)__kmp_fast_allocate(thread, shareds_offset + 1098 sizeof_shareds); 1099 #else /* ! USE_FAST_MEMORY */ 1100 taskdata = (kmp_taskdata_t *)__kmp_thread_malloc(thread, shareds_offset + 1101 sizeof_shareds); 1102 #endif /* USE_FAST_MEMORY */ 1103 ANNOTATE_HAPPENS_AFTER(taskdata); 1104 1105 task = KMP_TASKDATA_TO_TASK(taskdata); 1106 1107 // Make sure task & taskdata are aligned appropriately 1108 #if KMP_ARCH_X86 || KMP_ARCH_PPC64 || !KMP_HAVE_QUAD 1109 KMP_DEBUG_ASSERT((((kmp_uintptr_t)taskdata) & (sizeof(double) - 1)) == 0); 1110 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task) & (sizeof(double) - 1)) == 0); 1111 #else 1112 KMP_DEBUG_ASSERT((((kmp_uintptr_t)taskdata) & (sizeof(_Quad) - 1)) == 0); 1113 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task) & (sizeof(_Quad) - 1)) == 0); 1114 #endif 1115 if (sizeof_shareds > 0) { 1116 // Avoid double allocation here by combining shareds with taskdata 1117 task->shareds = &((char *)taskdata)[shareds_offset]; 1118 // Make sure shareds struct is aligned to pointer size 1119 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task->shareds) & (sizeof(void *) - 1)) == 1120 0); 1121 } else { 1122 task->shareds = NULL; 1123 } 1124 task->routine = task_entry; 1125 task->part_id = 0; // AC: Always start with 0 part id 1126 1127 taskdata->td_task_id = KMP_GEN_TASK_ID(); 1128 taskdata->td_team = team; 1129 taskdata->td_alloc_thread = thread; 1130 taskdata->td_parent = parent_task; 1131 taskdata->td_level = parent_task->td_level + 1; // increment nesting level 1132 taskdata->td_untied_count = 0; 1133 taskdata->td_ident = loc_ref; 1134 taskdata->td_taskwait_ident = NULL; 1135 taskdata->td_taskwait_counter = 0; 1136 taskdata->td_taskwait_thread = 0; 1137 KMP_DEBUG_ASSERT(taskdata->td_parent != NULL); 1138 #if OMP_45_ENABLED 1139 // avoid copying icvs for proxy tasks 1140 if (flags->proxy == TASK_FULL) 1141 #endif 1142 copy_icvs(&taskdata->td_icvs, &taskdata->td_parent->td_icvs); 1143 1144 taskdata->td_flags.tiedness = flags->tiedness; 1145 taskdata->td_flags.final = flags->final; 1146 taskdata->td_flags.merged_if0 = flags->merged_if0; 1147 #if OMP_40_ENABLED 1148 taskdata->td_flags.destructors_thunk = flags->destructors_thunk; 1149 #endif // OMP_40_ENABLED 1150 #if OMP_45_ENABLED 1151 taskdata->td_flags.proxy = flags->proxy; 1152 taskdata->td_task_team = thread->th.th_task_team; 1153 taskdata->td_size_alloc = shareds_offset + sizeof_shareds; 1154 #endif 1155 taskdata->td_flags.tasktype = TASK_EXPLICIT; 1156 1157 // GEH - TODO: fix this to copy parent task's value of tasking_ser flag 1158 taskdata->td_flags.tasking_ser = (__kmp_tasking_mode == tskm_immediate_exec); 1159 1160 // GEH - TODO: fix this to copy parent task's value of team_serial flag 1161 taskdata->td_flags.team_serial = (team->t.t_serialized) ? 1 : 0; 1162 1163 // GEH - Note we serialize the task if the team is serialized to make sure 1164 // implicit parallel region tasks are not left until program termination to 1165 // execute. Also, it helps locality to execute immediately. 1166 1167 taskdata->td_flags.task_serial = 1168 (parent_task->td_flags.final || taskdata->td_flags.team_serial || 1169 taskdata->td_flags.tasking_ser); 1170 1171 taskdata->td_flags.started = 0; 1172 taskdata->td_flags.executing = 0; 1173 taskdata->td_flags.complete = 0; 1174 taskdata->td_flags.freed = 0; 1175 1176 taskdata->td_flags.native = flags->native; 1177 1178 taskdata->td_incomplete_child_tasks = 0; 1179 taskdata->td_allocated_child_tasks = 1; // start at one because counts current 1180 // task and children 1181 #if OMP_40_ENABLED 1182 taskdata->td_taskgroup = 1183 parent_task->td_taskgroup; // task inherits taskgroup from the parent task 1184 taskdata->td_dephash = NULL; 1185 taskdata->td_depnode = NULL; 1186 #endif 1187 if (flags->tiedness == TASK_UNTIED) 1188 taskdata->td_last_tied = NULL; // will be set when the task is scheduled 1189 else 1190 taskdata->td_last_tied = taskdata; 1191 1192 // Only need to keep track of child task counts if team parallel and tasking not 1193 // serialized or if it is a proxy task 1194 #if OMP_45_ENABLED 1195 if (flags->proxy == TASK_PROXY || 1196 !(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser)) 1197 #else 1198 if (!(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser)) 1199 #endif 1200 { 1201 KMP_TEST_THEN_INC32(&parent_task->td_incomplete_child_tasks); 1202 #if OMP_40_ENABLED 1203 if (parent_task->td_taskgroup) 1204 KMP_TEST_THEN_INC32((kmp_int32 *)(&parent_task->td_taskgroup->count)); 1205 #endif 1206 // Only need to keep track of allocated child tasks for explicit tasks since 1207 // implicit not deallocated 1208 if (taskdata->td_parent->td_flags.tasktype == TASK_EXPLICIT) { 1209 KMP_TEST_THEN_INC32(&taskdata->td_parent->td_allocated_child_tasks); 1210 } 1211 } 1212 1213 KA_TRACE(20, ("__kmp_task_alloc(exit): T#%d created task %p parent=%p\n", 1214 gtid, taskdata, taskdata->td_parent)); 1215 ANNOTATE_HAPPENS_BEFORE(task); 1216 1217 #if OMPT_SUPPORT 1218 if (UNLIKELY(ompt_enabled.enabled)) 1219 __ompt_task_init(taskdata, gtid); 1220 #endif 1221 1222 return task; 1223 } 1224 1225 kmp_task_t *__kmpc_omp_task_alloc(ident_t *loc_ref, kmp_int32 gtid, 1226 kmp_int32 flags, size_t sizeof_kmp_task_t, 1227 size_t sizeof_shareds, 1228 kmp_routine_entry_t task_entry) { 1229 kmp_task_t *retval; 1230 kmp_tasking_flags_t *input_flags = (kmp_tasking_flags_t *)&flags; 1231 1232 input_flags->native = FALSE; 1233 // __kmp_task_alloc() sets up all other runtime flags 1234 1235 #if OMP_45_ENABLED 1236 KA_TRACE(10, ("__kmpc_omp_task_alloc(enter): T#%d loc=%p, flags=(%s %s) " 1237 "sizeof_task=%ld sizeof_shared=%ld entry=%p\n", 1238 gtid, loc_ref, input_flags->tiedness ? "tied " : "untied", 1239 input_flags->proxy ? "proxy" : "", sizeof_kmp_task_t, 1240 sizeof_shareds, task_entry)); 1241 #else 1242 KA_TRACE(10, ("__kmpc_omp_task_alloc(enter): T#%d loc=%p, flags=(%s) " 1243 "sizeof_task=%ld sizeof_shared=%ld entry=%p\n", 1244 gtid, loc_ref, input_flags->tiedness ? "tied " : "untied", 1245 sizeof_kmp_task_t, sizeof_shareds, task_entry)); 1246 #endif 1247 1248 retval = __kmp_task_alloc(loc_ref, gtid, input_flags, sizeof_kmp_task_t, 1249 sizeof_shareds, task_entry); 1250 1251 KA_TRACE(20, ("__kmpc_omp_task_alloc(exit): T#%d retval %p\n", gtid, retval)); 1252 1253 return retval; 1254 } 1255 1256 // __kmp_invoke_task: invoke the specified task 1257 // 1258 // gtid: global thread ID of caller 1259 // task: the task to invoke 1260 // current_task: the task to resume after task invokation 1261 static void __kmp_invoke_task(kmp_int32 gtid, kmp_task_t *task, 1262 kmp_taskdata_t *current_task) { 1263 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 1264 kmp_uint64 cur_time; 1265 #if OMP_40_ENABLED 1266 int discard = 0 /* false */; 1267 #endif 1268 KA_TRACE( 1269 30, ("__kmp_invoke_task(enter): T#%d invoking task %p, current_task=%p\n", 1270 gtid, taskdata, current_task)); 1271 KMP_DEBUG_ASSERT(task); 1272 #if OMP_45_ENABLED 1273 if (taskdata->td_flags.proxy == TASK_PROXY && 1274 taskdata->td_flags.complete == 1) { 1275 // This is a proxy task that was already completed but it needs to run 1276 // its bottom-half finish 1277 KA_TRACE( 1278 30, 1279 ("__kmp_invoke_task: T#%d running bottom finish for proxy task %p\n", 1280 gtid, taskdata)); 1281 1282 __kmp_bottom_half_finish_proxy(gtid, task); 1283 1284 KA_TRACE(30, ("__kmp_invoke_task(exit): T#%d completed bottom finish for " 1285 "proxy task %p, resuming task %p\n", 1286 gtid, taskdata, current_task)); 1287 1288 return; 1289 } 1290 #endif 1291 1292 #if USE_ITT_BUILD && USE_ITT_NOTIFY 1293 if (__kmp_forkjoin_frames_mode == 3) { 1294 // Get the current time stamp to measure task execution time to correct 1295 // barrier imbalance time 1296 cur_time = __itt_get_timestamp(); 1297 } 1298 #endif 1299 1300 #if OMP_45_ENABLED 1301 // Proxy tasks are not handled by the runtime 1302 if (taskdata->td_flags.proxy != TASK_PROXY) { 1303 #endif 1304 ANNOTATE_HAPPENS_AFTER(task); 1305 __kmp_task_start(gtid, task, current_task); // OMPT only if not discarded 1306 #if OMP_45_ENABLED 1307 } 1308 #endif 1309 1310 #if OMPT_SUPPORT 1311 ompt_thread_info_t oldInfo; 1312 kmp_info_t *thread; 1313 if (UNLIKELY(ompt_enabled.enabled)) { 1314 // Store the threads states and restore them after the task 1315 thread = __kmp_threads[gtid]; 1316 oldInfo = thread->th.ompt_thread_info; 1317 thread->th.ompt_thread_info.wait_id = 0; 1318 thread->th.ompt_thread_info.state = (thread->th.th_team_serialized) 1319 ? omp_state_work_serial 1320 : omp_state_work_parallel; 1321 taskdata->ompt_task_info.frame.exit_frame = OMPT_GET_FRAME_ADDRESS(0); 1322 } 1323 #endif 1324 1325 #if OMP_40_ENABLED 1326 // TODO: cancel tasks if the parallel region has also been cancelled 1327 // TODO: check if this sequence can be hoisted above __kmp_task_start 1328 // if cancellation has been enabled for this run ... 1329 if (__kmp_omp_cancellation) { 1330 kmp_info_t *this_thr = __kmp_threads[gtid]; 1331 kmp_team_t *this_team = this_thr->th.th_team; 1332 kmp_taskgroup_t *taskgroup = taskdata->td_taskgroup; 1333 if ((taskgroup && taskgroup->cancel_request) || 1334 (this_team->t.t_cancel_request == cancel_parallel)) { 1335 #if OMPT_SUPPORT && OMPT_OPTIONAL 1336 ompt_data_t *task_data; 1337 if (UNLIKELY(ompt_enabled.ompt_callback_cancel)) { 1338 __ompt_get_task_info_internal(0, NULL, &task_data, NULL, NULL, NULL); 1339 ompt_callbacks.ompt_callback(ompt_callback_cancel)( 1340 task_data, 1341 ((taskgroup && taskgroup->cancel_request) ? ompt_cancel_taskgroup 1342 : ompt_cancel_parallel) | 1343 ompt_cancel_discarded_task, 1344 NULL); 1345 } 1346 #endif 1347 KMP_COUNT_BLOCK(TASK_cancelled); 1348 // this task belongs to a task group and we need to cancel it 1349 discard = 1 /* true */; 1350 } 1351 } 1352 1353 // Invoke the task routine and pass in relevant data. 1354 // Thunks generated by gcc take a different argument list. 1355 if (!discard) { 1356 if (taskdata->td_flags.tiedness == TASK_UNTIED) { 1357 taskdata->td_last_tied = current_task->td_last_tied; 1358 KMP_DEBUG_ASSERT(taskdata->td_last_tied); 1359 } 1360 #if KMP_STATS_ENABLED 1361 KMP_COUNT_BLOCK(TASK_executed); 1362 switch (KMP_GET_THREAD_STATE()) { 1363 case FORK_JOIN_BARRIER: 1364 KMP_PUSH_PARTITIONED_TIMER(OMP_task_join_bar); 1365 break; 1366 case PLAIN_BARRIER: 1367 KMP_PUSH_PARTITIONED_TIMER(OMP_task_plain_bar); 1368 break; 1369 case TASKYIELD: 1370 KMP_PUSH_PARTITIONED_TIMER(OMP_task_taskyield); 1371 break; 1372 case TASKWAIT: 1373 KMP_PUSH_PARTITIONED_TIMER(OMP_task_taskwait); 1374 break; 1375 case TASKGROUP: 1376 KMP_PUSH_PARTITIONED_TIMER(OMP_task_taskgroup); 1377 break; 1378 default: 1379 KMP_PUSH_PARTITIONED_TIMER(OMP_task_immediate); 1380 break; 1381 } 1382 #endif // KMP_STATS_ENABLED 1383 #endif // OMP_40_ENABLED 1384 1385 // OMPT task begin 1386 #if OMPT_SUPPORT 1387 if (UNLIKELY(ompt_enabled.enabled)) 1388 __ompt_task_start(task, current_task, gtid); 1389 #endif 1390 1391 #ifdef KMP_GOMP_COMPAT 1392 if (taskdata->td_flags.native) { 1393 ((void (*)(void *))(*(task->routine)))(task->shareds); 1394 } else 1395 #endif /* KMP_GOMP_COMPAT */ 1396 { 1397 (*(task->routine))(gtid, task); 1398 } 1399 KMP_POP_PARTITIONED_TIMER(); 1400 1401 #if OMPT_SUPPORT 1402 if (UNLIKELY(ompt_enabled.enabled)) 1403 __ompt_task_finish(task, current_task); 1404 #endif 1405 #if OMP_40_ENABLED 1406 } 1407 #endif // OMP_40_ENABLED 1408 1409 #if OMPT_SUPPORT 1410 if (UNLIKELY(ompt_enabled.enabled)) { 1411 thread->th.ompt_thread_info = oldInfo; 1412 taskdata->ompt_task_info.frame.exit_frame = NULL; 1413 } 1414 #endif 1415 1416 #if OMP_45_ENABLED 1417 // Proxy tasks are not handled by the runtime 1418 if (taskdata->td_flags.proxy != TASK_PROXY) { 1419 #endif 1420 ANNOTATE_HAPPENS_BEFORE(taskdata->td_parent); 1421 __kmp_task_finish(gtid, task, current_task); // OMPT only if not discarded 1422 #if OMP_45_ENABLED 1423 } 1424 #endif 1425 1426 #if USE_ITT_BUILD && USE_ITT_NOTIFY 1427 // Barrier imbalance - correct arrive time after the task finished 1428 if (__kmp_forkjoin_frames_mode == 3) { 1429 kmp_info_t *this_thr = __kmp_threads[gtid]; 1430 if (this_thr->th.th_bar_arrive_time) { 1431 this_thr->th.th_bar_arrive_time += (__itt_get_timestamp() - cur_time); 1432 } 1433 } 1434 #endif 1435 KA_TRACE( 1436 30, 1437 ("__kmp_invoke_task(exit): T#%d completed task %p, resuming task %p\n", 1438 gtid, taskdata, current_task)); 1439 return; 1440 } 1441 1442 // __kmpc_omp_task_parts: Schedule a thread-switchable task for execution 1443 // 1444 // loc_ref: location of original task pragma (ignored) 1445 // gtid: Global Thread ID of encountering thread 1446 // new_task: task thunk allocated by __kmp_omp_task_alloc() for the ''new task'' 1447 // Returns: 1448 // TASK_CURRENT_NOT_QUEUED (0) if did not suspend and queue current task to 1449 // be resumed later. 1450 // TASK_CURRENT_QUEUED (1) if suspended and queued the current task to be 1451 // resumed later. 1452 kmp_int32 __kmpc_omp_task_parts(ident_t *loc_ref, kmp_int32 gtid, 1453 kmp_task_t *new_task) { 1454 kmp_taskdata_t *new_taskdata = KMP_TASK_TO_TASKDATA(new_task); 1455 1456 KA_TRACE(10, ("__kmpc_omp_task_parts(enter): T#%d loc=%p task=%p\n", gtid, 1457 loc_ref, new_taskdata)); 1458 1459 #if OMPT_SUPPORT 1460 kmp_taskdata_t *parent; 1461 if (UNLIKELY(ompt_enabled.enabled)) { 1462 parent = new_taskdata->td_parent; 1463 if (ompt_enabled.ompt_callback_task_create) { 1464 ompt_data_t task_data = ompt_data_none; 1465 ompt_callbacks.ompt_callback(ompt_callback_task_create)( 1466 parent ? &(parent->ompt_task_info.task_data) : &task_data, 1467 parent ? &(parent->ompt_task_info.frame) : NULL, 1468 &(new_taskdata->ompt_task_info.task_data), ompt_task_explicit, 0, 1469 OMPT_GET_RETURN_ADDRESS(0)); 1470 } 1471 } 1472 #endif 1473 1474 /* Should we execute the new task or queue it? For now, let's just always try 1475 to queue it. If the queue fills up, then we'll execute it. */ 1476 1477 if (__kmp_push_task(gtid, new_task) == TASK_NOT_PUSHED) // if cannot defer 1478 { // Execute this task immediately 1479 kmp_taskdata_t *current_task = __kmp_threads[gtid]->th.th_current_task; 1480 new_taskdata->td_flags.task_serial = 1; 1481 __kmp_invoke_task(gtid, new_task, current_task); 1482 } 1483 1484 KA_TRACE( 1485 10, 1486 ("__kmpc_omp_task_parts(exit): T#%d returning TASK_CURRENT_NOT_QUEUED: " 1487 "loc=%p task=%p, return: TASK_CURRENT_NOT_QUEUED\n", 1488 gtid, loc_ref, new_taskdata)); 1489 1490 ANNOTATE_HAPPENS_BEFORE(new_task); 1491 #if OMPT_SUPPORT 1492 if (UNLIKELY(ompt_enabled.enabled)) { 1493 parent->ompt_task_info.frame.enter_frame = NULL; 1494 } 1495 #endif 1496 return TASK_CURRENT_NOT_QUEUED; 1497 } 1498 1499 // __kmp_omp_task: Schedule a non-thread-switchable task for execution 1500 // 1501 // gtid: Global Thread ID of encountering thread 1502 // new_task:non-thread-switchable task thunk allocated by __kmp_omp_task_alloc() 1503 // serialize_immediate: if TRUE then if the task is executed immediately its 1504 // execution will be serialized 1505 // Returns: 1506 // TASK_CURRENT_NOT_QUEUED (0) if did not suspend and queue current task to 1507 // be resumed later. 1508 // TASK_CURRENT_QUEUED (1) if suspended and queued the current task to be 1509 // resumed later. 1510 kmp_int32 __kmp_omp_task(kmp_int32 gtid, kmp_task_t *new_task, 1511 bool serialize_immediate) { 1512 kmp_taskdata_t *new_taskdata = KMP_TASK_TO_TASKDATA(new_task); 1513 1514 /* Should we execute the new task or queue it? For now, let's just always try to 1515 queue it. If the queue fills up, then we'll execute it. */ 1516 #if OMP_45_ENABLED 1517 if (new_taskdata->td_flags.proxy == TASK_PROXY || 1518 __kmp_push_task(gtid, new_task) == TASK_NOT_PUSHED) // if cannot defer 1519 #else 1520 if (__kmp_push_task(gtid, new_task) == TASK_NOT_PUSHED) // if cannot defer 1521 #endif 1522 { // Execute this task immediately 1523 kmp_taskdata_t *current_task = __kmp_threads[gtid]->th.th_current_task; 1524 if (serialize_immediate) 1525 new_taskdata->td_flags.task_serial = 1; 1526 __kmp_invoke_task(gtid, new_task, current_task); 1527 } 1528 1529 ANNOTATE_HAPPENS_BEFORE(new_task); 1530 return TASK_CURRENT_NOT_QUEUED; 1531 } 1532 1533 // __kmpc_omp_task: Wrapper around __kmp_omp_task to schedule a 1534 // non-thread-switchable task from the parent thread only! 1535 // 1536 // loc_ref: location of original task pragma (ignored) 1537 // gtid: Global Thread ID of encountering thread 1538 // new_task: non-thread-switchable task thunk allocated by 1539 // __kmp_omp_task_alloc() 1540 // Returns: 1541 // TASK_CURRENT_NOT_QUEUED (0) if did not suspend and queue current task to 1542 // be resumed later. 1543 // TASK_CURRENT_QUEUED (1) if suspended and queued the current task to be 1544 // resumed later. 1545 kmp_int32 __kmpc_omp_task(ident_t *loc_ref, kmp_int32 gtid, 1546 kmp_task_t *new_task) { 1547 kmp_int32 res; 1548 KMP_SET_THREAD_STATE_BLOCK(EXPLICIT_TASK); 1549 1550 #if KMP_DEBUG || OMPT_SUPPORT 1551 kmp_taskdata_t *new_taskdata = KMP_TASK_TO_TASKDATA(new_task); 1552 #endif 1553 KA_TRACE(10, ("__kmpc_omp_task(enter): T#%d loc=%p task=%p\n", gtid, loc_ref, 1554 new_taskdata)); 1555 1556 #if OMPT_SUPPORT 1557 kmp_taskdata_t *parent = NULL; 1558 if (UNLIKELY(ompt_enabled.enabled && !new_taskdata->td_flags.started)) { 1559 OMPT_STORE_RETURN_ADDRESS(gtid); 1560 parent = new_taskdata->td_parent; 1561 if (!parent->ompt_task_info.frame.enter_frame) 1562 parent->ompt_task_info.frame.enter_frame = OMPT_GET_FRAME_ADDRESS(1); 1563 if (ompt_enabled.ompt_callback_task_create) { 1564 ompt_data_t task_data = ompt_data_none; 1565 ompt_callbacks.ompt_callback(ompt_callback_task_create)( 1566 parent ? &(parent->ompt_task_info.task_data) : &task_data, 1567 parent ? &(parent->ompt_task_info.frame) : NULL, 1568 &(new_taskdata->ompt_task_info.task_data), 1569 ompt_task_explicit | TASK_TYPE_DETAILS_FORMAT(new_taskdata), 0, 1570 OMPT_LOAD_RETURN_ADDRESS(gtid)); 1571 } 1572 } 1573 #endif 1574 1575 res = __kmp_omp_task(gtid, new_task, true); 1576 1577 KA_TRACE(10, ("__kmpc_omp_task(exit): T#%d returning " 1578 "TASK_CURRENT_NOT_QUEUED: loc=%p task=%p\n", 1579 gtid, loc_ref, new_taskdata)); 1580 #if OMPT_SUPPORT 1581 if (UNLIKELY(ompt_enabled.enabled && parent != NULL)) { 1582 parent->ompt_task_info.frame.enter_frame = NULL; 1583 } 1584 #endif 1585 return res; 1586 } 1587 1588 template <bool ompt> 1589 static kmp_int32 __kmpc_omp_taskwait_template(ident_t *loc_ref, kmp_int32 gtid, 1590 void *frame_address, 1591 void *return_address) { 1592 kmp_taskdata_t *taskdata; 1593 kmp_info_t *thread; 1594 int thread_finished = FALSE; 1595 KMP_SET_THREAD_STATE_BLOCK(TASKWAIT); 1596 1597 KA_TRACE(10, ("__kmpc_omp_taskwait(enter): T#%d loc=%p\n", gtid, loc_ref)); 1598 1599 if (__kmp_tasking_mode != tskm_immediate_exec) { 1600 thread = __kmp_threads[gtid]; 1601 taskdata = thread->th.th_current_task; 1602 1603 #if OMPT_SUPPORT && OMPT_OPTIONAL 1604 ompt_data_t *my_task_data; 1605 ompt_data_t *my_parallel_data; 1606 1607 if (ompt) { 1608 my_task_data = &(taskdata->ompt_task_info.task_data); 1609 my_parallel_data = OMPT_CUR_TEAM_DATA(thread); 1610 1611 taskdata->ompt_task_info.frame.enter_frame = frame_address; 1612 1613 if (ompt_enabled.ompt_callback_sync_region) { 1614 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 1615 ompt_sync_region_taskwait, ompt_scope_begin, my_parallel_data, 1616 my_task_data, return_address); 1617 } 1618 1619 if (ompt_enabled.ompt_callback_sync_region_wait) { 1620 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 1621 ompt_sync_region_taskwait, ompt_scope_begin, my_parallel_data, 1622 my_task_data, return_address); 1623 } 1624 } 1625 #endif // OMPT_SUPPORT && OMPT_OPTIONAL 1626 1627 // Debugger: The taskwait is active. Store location and thread encountered the 1628 // taskwait. 1629 #if USE_ITT_BUILD 1630 // Note: These values are used by ITT events as well. 1631 #endif /* USE_ITT_BUILD */ 1632 taskdata->td_taskwait_counter += 1; 1633 taskdata->td_taskwait_ident = loc_ref; 1634 taskdata->td_taskwait_thread = gtid + 1; 1635 1636 #if USE_ITT_BUILD 1637 void *itt_sync_obj = __kmp_itt_taskwait_object(gtid); 1638 if (itt_sync_obj != NULL) 1639 __kmp_itt_taskwait_starting(gtid, itt_sync_obj); 1640 #endif /* USE_ITT_BUILD */ 1641 1642 bool must_wait = 1643 !taskdata->td_flags.team_serial && !taskdata->td_flags.final; 1644 1645 #if OMP_45_ENABLED 1646 must_wait = must_wait || (thread->th.th_task_team != NULL && 1647 thread->th.th_task_team->tt.tt_found_proxy_tasks); 1648 #endif 1649 if (must_wait) { 1650 kmp_flag_32 flag( 1651 RCAST(volatile kmp_uint32 *, &taskdata->td_incomplete_child_tasks), 1652 0U); 1653 while (TCR_4(taskdata->td_incomplete_child_tasks) != 0) { 1654 flag.execute_tasks(thread, gtid, FALSE, 1655 &thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), 1656 __kmp_task_stealing_constraint); 1657 } 1658 } 1659 #if USE_ITT_BUILD 1660 if (itt_sync_obj != NULL) 1661 __kmp_itt_taskwait_finished(gtid, itt_sync_obj); 1662 #endif /* USE_ITT_BUILD */ 1663 1664 // Debugger: The taskwait is completed. Location remains, but thread is 1665 // negated. 1666 taskdata->td_taskwait_thread = -taskdata->td_taskwait_thread; 1667 1668 #if OMPT_SUPPORT && OMPT_OPTIONAL 1669 if (ompt) { 1670 if (ompt_enabled.ompt_callback_sync_region_wait) { 1671 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 1672 ompt_sync_region_taskwait, ompt_scope_end, my_parallel_data, 1673 my_task_data, return_address); 1674 } 1675 if (ompt_enabled.ompt_callback_sync_region) { 1676 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 1677 ompt_sync_region_taskwait, ompt_scope_end, my_parallel_data, 1678 my_task_data, return_address); 1679 } 1680 taskdata->ompt_task_info.frame.enter_frame = NULL; 1681 } 1682 #endif // OMPT_SUPPORT && OMPT_OPTIONAL 1683 1684 ANNOTATE_HAPPENS_AFTER(taskdata); 1685 } 1686 1687 KA_TRACE(10, ("__kmpc_omp_taskwait(exit): T#%d task %p finished waiting, " 1688 "returning TASK_CURRENT_NOT_QUEUED\n", 1689 gtid, taskdata)); 1690 1691 return TASK_CURRENT_NOT_QUEUED; 1692 } 1693 1694 #if OMPT_SUPPORT 1695 OMPT_NOINLINE 1696 static kmp_int32 __kmpc_omp_taskwait_ompt(ident_t *loc_ref, kmp_int32 gtid, 1697 void *frame_address, 1698 void *return_address) { 1699 return __kmpc_omp_taskwait_template<true>(loc_ref, gtid, frame_address, 1700 return_address); 1701 } 1702 #endif // OMPT_SUPPORT 1703 1704 // __kmpc_omp_taskwait: Wait until all tasks generated by the current task are 1705 // complete 1706 kmp_int32 __kmpc_omp_taskwait(ident_t *loc_ref, kmp_int32 gtid) { 1707 #if OMPT_SUPPORT && OMPT_OPTIONAL 1708 if (UNLIKELY(ompt_enabled.enabled)) { 1709 OMPT_STORE_RETURN_ADDRESS(gtid); 1710 return __kmpc_omp_taskwait_ompt(loc_ref, gtid, OMPT_GET_FRAME_ADDRESS(1), 1711 OMPT_LOAD_RETURN_ADDRESS(gtid)); 1712 } 1713 #endif 1714 return __kmpc_omp_taskwait_template<false>(loc_ref, gtid, NULL, NULL); 1715 } 1716 1717 // __kmpc_omp_taskyield: switch to a different task 1718 kmp_int32 __kmpc_omp_taskyield(ident_t *loc_ref, kmp_int32 gtid, int end_part) { 1719 kmp_taskdata_t *taskdata; 1720 kmp_info_t *thread; 1721 int thread_finished = FALSE; 1722 1723 KMP_COUNT_BLOCK(OMP_TASKYIELD); 1724 KMP_SET_THREAD_STATE_BLOCK(TASKYIELD); 1725 1726 KA_TRACE(10, ("__kmpc_omp_taskyield(enter): T#%d loc=%p end_part = %d\n", 1727 gtid, loc_ref, end_part)); 1728 1729 if (__kmp_tasking_mode != tskm_immediate_exec && __kmp_init_parallel) { 1730 thread = __kmp_threads[gtid]; 1731 taskdata = thread->th.th_current_task; 1732 // Should we model this as a task wait or not? 1733 // Debugger: The taskwait is active. Store location and thread encountered the 1734 // taskwait. 1735 #if USE_ITT_BUILD 1736 // Note: These values are used by ITT events as well. 1737 #endif /* USE_ITT_BUILD */ 1738 taskdata->td_taskwait_counter += 1; 1739 taskdata->td_taskwait_ident = loc_ref; 1740 taskdata->td_taskwait_thread = gtid + 1; 1741 1742 #if USE_ITT_BUILD 1743 void *itt_sync_obj = __kmp_itt_taskwait_object(gtid); 1744 if (itt_sync_obj != NULL) 1745 __kmp_itt_taskwait_starting(gtid, itt_sync_obj); 1746 #endif /* USE_ITT_BUILD */ 1747 if (!taskdata->td_flags.team_serial) { 1748 kmp_task_team_t *task_team = thread->th.th_task_team; 1749 if (task_team != NULL) { 1750 if (KMP_TASKING_ENABLED(task_team)) { 1751 #if OMPT_SUPPORT 1752 if (UNLIKELY(ompt_enabled.enabled)) 1753 thread->th.ompt_thread_info.ompt_task_yielded = 1; 1754 #endif 1755 __kmp_execute_tasks_32( 1756 thread, gtid, NULL, FALSE, 1757 &thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), 1758 __kmp_task_stealing_constraint); 1759 #if OMPT_SUPPORT 1760 if (UNLIKELY(ompt_enabled.enabled)) 1761 thread->th.ompt_thread_info.ompt_task_yielded = 0; 1762 #endif 1763 } 1764 } 1765 } 1766 #if USE_ITT_BUILD 1767 if (itt_sync_obj != NULL) 1768 __kmp_itt_taskwait_finished(gtid, itt_sync_obj); 1769 #endif /* USE_ITT_BUILD */ 1770 1771 // Debugger: The taskwait is completed. Location remains, but thread is 1772 // negated. 1773 taskdata->td_taskwait_thread = -taskdata->td_taskwait_thread; 1774 } 1775 1776 KA_TRACE(10, ("__kmpc_omp_taskyield(exit): T#%d task %p resuming, " 1777 "returning TASK_CURRENT_NOT_QUEUED\n", 1778 gtid, taskdata)); 1779 1780 return TASK_CURRENT_NOT_QUEUED; 1781 } 1782 1783 // TODO: change to OMP_50_ENABLED, need to change build tools for this to work 1784 #if OMP_45_ENABLED 1785 // Task Reduction implementation 1786 1787 typedef struct kmp_task_red_flags { 1788 unsigned lazy_priv : 1; // hint: (1) use lazy allocation (big objects) 1789 unsigned reserved31 : 31; 1790 } kmp_task_red_flags_t; 1791 1792 // internal structure for reduction data item related info 1793 typedef struct kmp_task_red_data { 1794 void *reduce_shar; // shared reduction item 1795 size_t reduce_size; // size of data item 1796 void *reduce_priv; // thread specific data 1797 void *reduce_pend; // end of private data for comparison op 1798 void *reduce_init; // data initialization routine 1799 void *reduce_fini; // data finalization routine 1800 void *reduce_comb; // data combiner routine 1801 kmp_task_red_flags_t flags; // flags for additional info from compiler 1802 } kmp_task_red_data_t; 1803 1804 // structure sent us by compiler - one per reduction item 1805 typedef struct kmp_task_red_input { 1806 void *reduce_shar; // shared reduction item 1807 size_t reduce_size; // size of data item 1808 void *reduce_init; // data initialization routine 1809 void *reduce_fini; // data finalization routine 1810 void *reduce_comb; // data combiner routine 1811 kmp_task_red_flags_t flags; // flags for additional info from compiler 1812 } kmp_task_red_input_t; 1813 1814 /*! 1815 @ingroup TASKING 1816 @param gtid Global thread ID 1817 @param num Number of data items to reduce 1818 @param data Array of data for reduction 1819 @return The taskgroup identifier 1820 1821 Initialize task reduction for the taskgroup. 1822 */ 1823 void *__kmpc_task_reduction_init(int gtid, int num, void *data) { 1824 kmp_info_t *thread = __kmp_threads[gtid]; 1825 kmp_taskgroup_t *tg = thread->th.th_current_task->td_taskgroup; 1826 kmp_int32 nth = thread->th.th_team_nproc; 1827 kmp_task_red_input_t *input = (kmp_task_red_input_t *)data; 1828 kmp_task_red_data_t *arr; 1829 1830 // check input data just in case 1831 KMP_ASSERT(tg != NULL); 1832 KMP_ASSERT(data != NULL); 1833 KMP_ASSERT(num > 0); 1834 if (nth == 1) { 1835 KA_TRACE(10, ("__kmpc_task_reduction_init: T#%d, tg %p, exiting nth=1\n", 1836 gtid, tg)); 1837 return (void *)tg; 1838 } 1839 KA_TRACE(10, ("__kmpc_task_reduction_init: T#%d, taskgroup %p, #items %d\n", 1840 gtid, tg, num)); 1841 arr = (kmp_task_red_data_t *)__kmp_thread_malloc( 1842 thread, num * sizeof(kmp_task_red_data_t)); 1843 for (int i = 0; i < num; ++i) { 1844 void (*f_init)(void *) = (void (*)(void *))(input[i].reduce_init); 1845 size_t size = input[i].reduce_size - 1; 1846 // round the size up to cache line per thread-specific item 1847 size += CACHE_LINE - size % CACHE_LINE; 1848 KMP_ASSERT(input[i].reduce_comb != NULL); // combiner is mandatory 1849 arr[i].reduce_shar = input[i].reduce_shar; 1850 arr[i].reduce_size = size; 1851 arr[i].reduce_init = input[i].reduce_init; 1852 arr[i].reduce_fini = input[i].reduce_fini; 1853 arr[i].reduce_comb = input[i].reduce_comb; 1854 arr[i].flags = input[i].flags; 1855 if (!input[i].flags.lazy_priv) { 1856 // allocate cache-line aligned block and fill it with zeros 1857 arr[i].reduce_priv = __kmp_allocate(nth * size); 1858 arr[i].reduce_pend = (char *)(arr[i].reduce_priv) + nth * size; 1859 if (f_init != NULL) { 1860 // initialize thread-specific items 1861 for (int j = 0; j < nth; ++j) { 1862 f_init((char *)(arr[i].reduce_priv) + j * size); 1863 } 1864 } 1865 } else { 1866 // only allocate space for pointers now, 1867 // objects will be lazily allocated/initialized once requested 1868 arr[i].reduce_priv = __kmp_allocate(nth * sizeof(void *)); 1869 } 1870 } 1871 tg->reduce_data = (void *)arr; 1872 tg->reduce_num_data = num; 1873 return (void *)tg; 1874 } 1875 1876 /*! 1877 @ingroup TASKING 1878 @param gtid Global thread ID 1879 @param tskgrp The taskgroup ID (optional) 1880 @param data Shared location of the item 1881 @return The pointer to per-thread data 1882 1883 Get thread-specific location of data item 1884 */ 1885 void *__kmpc_task_reduction_get_th_data(int gtid, void *tskgrp, void *data) { 1886 kmp_info_t *thread = __kmp_threads[gtid]; 1887 kmp_int32 nth = thread->th.th_team_nproc; 1888 if (nth == 1) 1889 return data; // nothing to do 1890 1891 kmp_taskgroup_t *tg = (kmp_taskgroup_t *)tskgrp; 1892 if (tg == NULL) 1893 tg = thread->th.th_current_task->td_taskgroup; 1894 KMP_ASSERT(tg != NULL); 1895 kmp_task_red_data_t *arr = (kmp_task_red_data_t *)(tg->reduce_data); 1896 kmp_int32 num = tg->reduce_num_data; 1897 kmp_int32 tid = thread->th.th_info.ds.ds_tid; 1898 1899 KMP_ASSERT(data != NULL); 1900 while (tg != NULL) { 1901 for (int i = 0; i < num; ++i) { 1902 if (!arr[i].flags.lazy_priv) { 1903 if (data == arr[i].reduce_shar || 1904 (data >= arr[i].reduce_priv && data < arr[i].reduce_pend)) 1905 return (char *)(arr[i].reduce_priv) + tid * arr[i].reduce_size; 1906 } else { 1907 // check shared location first 1908 void **p_priv = (void **)(arr[i].reduce_priv); 1909 if (data == arr[i].reduce_shar) 1910 goto found; 1911 // check if we get some thread specific location as parameter 1912 for (int j = 0; j < nth; ++j) 1913 if (data == p_priv[j]) 1914 goto found; 1915 continue; // not found, continue search 1916 found: 1917 if (p_priv[tid] == NULL) { 1918 // allocate thread specific object lazily 1919 void (*f_init)(void *) = (void (*)(void *))(arr[i].reduce_init); 1920 p_priv[tid] = __kmp_allocate(arr[i].reduce_size); 1921 if (f_init != NULL) { 1922 f_init(p_priv[tid]); 1923 } 1924 } 1925 return p_priv[tid]; 1926 } 1927 } 1928 tg = tg->parent; 1929 arr = (kmp_task_red_data_t *)(tg->reduce_data); 1930 num = tg->reduce_num_data; 1931 } 1932 KMP_ASSERT2(0, "Unknown task reduction item"); 1933 return NULL; // ERROR, this line never executed 1934 } 1935 1936 // Finalize task reduction. 1937 // Called from __kmpc_end_taskgroup() 1938 static void __kmp_task_reduction_fini(kmp_info_t *th, kmp_taskgroup_t *tg) { 1939 kmp_int32 nth = th->th.th_team_nproc; 1940 KMP_DEBUG_ASSERT(nth > 1); // should not be called if nth == 1 1941 kmp_task_red_data_t *arr = (kmp_task_red_data_t *)tg->reduce_data; 1942 kmp_int32 num = tg->reduce_num_data; 1943 for (int i = 0; i < num; ++i) { 1944 void *sh_data = arr[i].reduce_shar; 1945 void (*f_fini)(void *) = (void (*)(void *))(arr[i].reduce_fini); 1946 void (*f_comb)(void *, void *) = 1947 (void (*)(void *, void *))(arr[i].reduce_comb); 1948 if (!arr[i].flags.lazy_priv) { 1949 void *pr_data = arr[i].reduce_priv; 1950 size_t size = arr[i].reduce_size; 1951 for (int j = 0; j < nth; ++j) { 1952 void *priv_data = (char *)pr_data + j * size; 1953 f_comb(sh_data, priv_data); // combine results 1954 if (f_fini) 1955 f_fini(priv_data); // finalize if needed 1956 } 1957 } else { 1958 void **pr_data = (void **)(arr[i].reduce_priv); 1959 for (int j = 0; j < nth; ++j) { 1960 if (pr_data[j] != NULL) { 1961 f_comb(sh_data, pr_data[j]); // combine results 1962 if (f_fini) 1963 f_fini(pr_data[j]); // finalize if needed 1964 __kmp_free(pr_data[j]); 1965 } 1966 } 1967 } 1968 __kmp_free(arr[i].reduce_priv); 1969 } 1970 __kmp_thread_free(th, arr); 1971 tg->reduce_data = NULL; 1972 tg->reduce_num_data = 0; 1973 } 1974 #endif 1975 1976 #if OMP_40_ENABLED 1977 // __kmpc_taskgroup: Start a new taskgroup 1978 void __kmpc_taskgroup(ident_t *loc, int gtid) { 1979 kmp_info_t *thread = __kmp_threads[gtid]; 1980 kmp_taskdata_t *taskdata = thread->th.th_current_task; 1981 kmp_taskgroup_t *tg_new = 1982 (kmp_taskgroup_t *)__kmp_thread_malloc(thread, sizeof(kmp_taskgroup_t)); 1983 KA_TRACE(10, ("__kmpc_taskgroup: T#%d loc=%p group=%p\n", gtid, loc, tg_new)); 1984 tg_new->count = 0; 1985 tg_new->cancel_request = cancel_noreq; 1986 tg_new->parent = taskdata->td_taskgroup; 1987 // TODO: change to OMP_50_ENABLED, need to change build tools for this to work 1988 #if OMP_45_ENABLED 1989 tg_new->reduce_data = NULL; 1990 tg_new->reduce_num_data = 0; 1991 #endif 1992 taskdata->td_taskgroup = tg_new; 1993 1994 #if OMPT_SUPPORT && OMPT_OPTIONAL 1995 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region)) { 1996 void *codeptr = OMPT_LOAD_RETURN_ADDRESS(gtid); 1997 if (!codeptr) 1998 codeptr = OMPT_GET_RETURN_ADDRESS(0); 1999 kmp_team_t *team = thread->th.th_team; 2000 ompt_data_t my_task_data = taskdata->ompt_task_info.task_data; 2001 // FIXME: I think this is wrong for lwt! 2002 ompt_data_t my_parallel_data = team->t.ompt_team_info.parallel_data; 2003 2004 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 2005 ompt_sync_region_taskgroup, ompt_scope_begin, &(my_parallel_data), 2006 &(my_task_data), codeptr); 2007 } 2008 #endif 2009 } 2010 2011 // __kmpc_end_taskgroup: Wait until all tasks generated by the current task 2012 // and its descendants are complete 2013 void __kmpc_end_taskgroup(ident_t *loc, int gtid) { 2014 kmp_info_t *thread = __kmp_threads[gtid]; 2015 kmp_taskdata_t *taskdata = thread->th.th_current_task; 2016 kmp_taskgroup_t *taskgroup = taskdata->td_taskgroup; 2017 int thread_finished = FALSE; 2018 2019 #if OMPT_SUPPORT && OMPT_OPTIONAL 2020 kmp_team_t *team; 2021 ompt_data_t my_task_data; 2022 ompt_data_t my_parallel_data; 2023 void *codeptr; 2024 if (UNLIKELY(ompt_enabled.enabled)) { 2025 team = thread->th.th_team; 2026 my_task_data = taskdata->ompt_task_info.task_data; 2027 // FIXME: I think this is wrong for lwt! 2028 my_parallel_data = team->t.ompt_team_info.parallel_data; 2029 codeptr = OMPT_LOAD_RETURN_ADDRESS(gtid); 2030 if (!codeptr) 2031 codeptr = OMPT_GET_RETURN_ADDRESS(0); 2032 } 2033 #endif 2034 2035 KA_TRACE(10, ("__kmpc_end_taskgroup(enter): T#%d loc=%p\n", gtid, loc)); 2036 KMP_DEBUG_ASSERT(taskgroup != NULL); 2037 KMP_SET_THREAD_STATE_BLOCK(TASKGROUP); 2038 2039 if (__kmp_tasking_mode != tskm_immediate_exec) { 2040 // mark task as waiting not on a barrier 2041 taskdata->td_taskwait_counter += 1; 2042 taskdata->td_taskwait_ident = loc; 2043 taskdata->td_taskwait_thread = gtid + 1; 2044 #if USE_ITT_BUILD 2045 // For ITT the taskgroup wait is similar to taskwait until we need to 2046 // distinguish them 2047 void *itt_sync_obj = __kmp_itt_taskwait_object(gtid); 2048 if (itt_sync_obj != NULL) 2049 __kmp_itt_taskwait_starting(gtid, itt_sync_obj); 2050 #endif /* USE_ITT_BUILD */ 2051 2052 #if OMPT_SUPPORT && OMPT_OPTIONAL 2053 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region_wait)) { 2054 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 2055 ompt_sync_region_taskgroup, ompt_scope_begin, &(my_parallel_data), 2056 &(my_task_data), codeptr); 2057 } 2058 #endif 2059 2060 #if OMP_45_ENABLED 2061 if (!taskdata->td_flags.team_serial || 2062 (thread->th.th_task_team != NULL && 2063 thread->th.th_task_team->tt.tt_found_proxy_tasks)) 2064 #else 2065 if (!taskdata->td_flags.team_serial) 2066 #endif 2067 { 2068 kmp_flag_32 flag(RCAST(kmp_uint32 *, &taskgroup->count), 0U); 2069 while (TCR_4(taskgroup->count) != 0) { 2070 flag.execute_tasks(thread, gtid, FALSE, 2071 &thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), 2072 __kmp_task_stealing_constraint); 2073 } 2074 } 2075 taskdata->td_taskwait_thread = -taskdata->td_taskwait_thread; // end waiting 2076 2077 #if OMPT_SUPPORT && OMPT_OPTIONAL 2078 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region_wait)) { 2079 ompt_callbacks.ompt_callback(ompt_callback_sync_region_wait)( 2080 ompt_sync_region_taskgroup, ompt_scope_end, &(my_parallel_data), 2081 &(my_task_data), codeptr); 2082 } 2083 #endif 2084 2085 #if USE_ITT_BUILD 2086 if (itt_sync_obj != NULL) 2087 __kmp_itt_taskwait_finished(gtid, itt_sync_obj); 2088 #endif /* USE_ITT_BUILD */ 2089 } 2090 KMP_DEBUG_ASSERT(taskgroup->count == 0); 2091 2092 // TODO: change to OMP_50_ENABLED, need to change build tools for this to work 2093 #if OMP_45_ENABLED 2094 if (taskgroup->reduce_data != NULL) // need to reduce? 2095 __kmp_task_reduction_fini(thread, taskgroup); 2096 #endif 2097 // Restore parent taskgroup for the current task 2098 taskdata->td_taskgroup = taskgroup->parent; 2099 __kmp_thread_free(thread, taskgroup); 2100 2101 KA_TRACE(10, ("__kmpc_end_taskgroup(exit): T#%d task %p finished waiting\n", 2102 gtid, taskdata)); 2103 ANNOTATE_HAPPENS_AFTER(taskdata); 2104 2105 #if OMPT_SUPPORT && OMPT_OPTIONAL 2106 if (UNLIKELY(ompt_enabled.ompt_callback_sync_region)) { 2107 ompt_callbacks.ompt_callback(ompt_callback_sync_region)( 2108 ompt_sync_region_taskgroup, ompt_scope_end, &(my_parallel_data), 2109 &(my_task_data), codeptr); 2110 } 2111 #endif 2112 } 2113 #endif 2114 2115 // __kmp_remove_my_task: remove a task from my own deque 2116 static kmp_task_t *__kmp_remove_my_task(kmp_info_t *thread, kmp_int32 gtid, 2117 kmp_task_team_t *task_team, 2118 kmp_int32 is_constrained) { 2119 kmp_task_t *task; 2120 kmp_taskdata_t *taskdata; 2121 kmp_thread_data_t *thread_data; 2122 kmp_uint32 tail; 2123 2124 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 2125 KMP_DEBUG_ASSERT(task_team->tt.tt_threads_data != 2126 NULL); // Caller should check this condition 2127 2128 thread_data = &task_team->tt.tt_threads_data[__kmp_tid_from_gtid(gtid)]; 2129 2130 KA_TRACE(10, ("__kmp_remove_my_task(enter): T#%d ntasks=%d head=%u tail=%u\n", 2131 gtid, thread_data->td.td_deque_ntasks, 2132 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2133 2134 if (TCR_4(thread_data->td.td_deque_ntasks) == 0) { 2135 KA_TRACE(10, 2136 ("__kmp_remove_my_task(exit #1): T#%d No tasks to remove: " 2137 "ntasks=%d head=%u tail=%u\n", 2138 gtid, thread_data->td.td_deque_ntasks, 2139 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2140 return NULL; 2141 } 2142 2143 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 2144 2145 if (TCR_4(thread_data->td.td_deque_ntasks) == 0) { 2146 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2147 KA_TRACE(10, 2148 ("__kmp_remove_my_task(exit #2): T#%d No tasks to remove: " 2149 "ntasks=%d head=%u tail=%u\n", 2150 gtid, thread_data->td.td_deque_ntasks, 2151 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2152 return NULL; 2153 } 2154 2155 tail = (thread_data->td.td_deque_tail - 1) & 2156 TASK_DEQUE_MASK(thread_data->td); // Wrap index. 2157 taskdata = thread_data->td.td_deque[tail]; 2158 2159 if (is_constrained && (taskdata->td_flags.tiedness == TASK_TIED)) { 2160 // we need to check if the candidate obeys task scheduling constraint (TSC) 2161 // only descendant of all deferred tied tasks can be scheduled, checking 2162 // the last one is enough, as it in turn is the descendant of all others 2163 kmp_taskdata_t *current = thread->th.th_current_task->td_last_tied; 2164 KMP_DEBUG_ASSERT(current != NULL); 2165 // check if last tied task is not suspended on barrier 2166 if (current->td_flags.tasktype == TASK_EXPLICIT || 2167 current->td_taskwait_thread > 0) { // <= 0 on barrier 2168 kmp_int32 level = current->td_level; 2169 kmp_taskdata_t *parent = taskdata->td_parent; 2170 while (parent != current && parent->td_level > level) { 2171 parent = parent->td_parent; // check generation up to the level of the 2172 // current task 2173 KMP_DEBUG_ASSERT(parent != NULL); 2174 } 2175 if (parent != current) { 2176 // The TSC does not allow to steal victim task 2177 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2178 KA_TRACE(10, ("__kmp_remove_my_task(exit #2): T#%d No tasks to remove: " 2179 "ntasks=%d head=%u tail=%u\n", 2180 gtid, thread_data->td.td_deque_ntasks, 2181 thread_data->td.td_deque_head, 2182 thread_data->td.td_deque_tail)); 2183 return NULL; 2184 } 2185 } 2186 } 2187 2188 thread_data->td.td_deque_tail = tail; 2189 TCW_4(thread_data->td.td_deque_ntasks, thread_data->td.td_deque_ntasks - 1); 2190 2191 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2192 2193 KA_TRACE(10, ("__kmp_remove_my_task(exit #2): T#%d task %p removed: " 2194 "ntasks=%d head=%u tail=%u\n", 2195 gtid, taskdata, thread_data->td.td_deque_ntasks, 2196 thread_data->td.td_deque_head, thread_data->td.td_deque_tail)); 2197 2198 task = KMP_TASKDATA_TO_TASK(taskdata); 2199 return task; 2200 } 2201 2202 // __kmp_steal_task: remove a task from another thread's deque 2203 // Assume that calling thread has already checked existence of 2204 // task_team thread_data before calling this routine. 2205 static kmp_task_t *__kmp_steal_task(kmp_info_t *victim_thr, kmp_int32 gtid, 2206 kmp_task_team_t *task_team, 2207 volatile kmp_int32 *unfinished_threads, 2208 int *thread_finished, 2209 kmp_int32 is_constrained) { 2210 kmp_task_t *task; 2211 kmp_taskdata_t *taskdata; 2212 kmp_taskdata_t *current; 2213 kmp_thread_data_t *victim_td, *threads_data; 2214 kmp_int32 level, target; 2215 kmp_int32 victim_tid; 2216 2217 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 2218 2219 threads_data = task_team->tt.tt_threads_data; 2220 KMP_DEBUG_ASSERT(threads_data != NULL); // Caller should check this condition 2221 2222 victim_tid = victim_thr->th.th_info.ds.ds_tid; 2223 victim_td = &threads_data[victim_tid]; 2224 2225 KA_TRACE(10, ("__kmp_steal_task(enter): T#%d try to steal from T#%d: " 2226 "task_team=%p ntasks=%d head=%u tail=%u\n", 2227 gtid, __kmp_gtid_from_thread(victim_thr), task_team, 2228 victim_td->td.td_deque_ntasks, victim_td->td.td_deque_head, 2229 victim_td->td.td_deque_tail)); 2230 2231 if (TCR_4(victim_td->td.td_deque_ntasks) == 0) { 2232 KA_TRACE(10, ("__kmp_steal_task(exit #1): T#%d could not steal from T#%d: " 2233 "task_team=%p ntasks=%d head=%u tail=%u\n", 2234 gtid, __kmp_gtid_from_thread(victim_thr), task_team, 2235 victim_td->td.td_deque_ntasks, victim_td->td.td_deque_head, 2236 victim_td->td.td_deque_tail)); 2237 return NULL; 2238 } 2239 2240 __kmp_acquire_bootstrap_lock(&victim_td->td.td_deque_lock); 2241 2242 int ntasks = TCR_4(victim_td->td.td_deque_ntasks); 2243 // Check again after we acquire the lock 2244 if (ntasks == 0) { 2245 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2246 KA_TRACE(10, ("__kmp_steal_task(exit #2): T#%d could not steal from T#%d: " 2247 "task_team=%p ntasks=%d head=%u tail=%u\n", 2248 gtid, __kmp_gtid_from_thread(victim_thr), task_team, ntasks, 2249 victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2250 return NULL; 2251 } 2252 2253 KMP_DEBUG_ASSERT(victim_td->td.td_deque != NULL); 2254 2255 taskdata = victim_td->td.td_deque[victim_td->td.td_deque_head]; 2256 if (is_constrained && (taskdata->td_flags.tiedness == TASK_TIED)) { 2257 // we need to check if the candidate obeys task scheduling constraint (TSC) 2258 // only descendant of all deferred tied tasks can be scheduled, checking 2259 // the last one is enough, as it in turn is the descendant of all others 2260 current = __kmp_threads[gtid]->th.th_current_task->td_last_tied; 2261 KMP_DEBUG_ASSERT(current != NULL); 2262 // check if last tied task is not suspended on barrier 2263 if (current->td_flags.tasktype == TASK_EXPLICIT || 2264 current->td_taskwait_thread > 0) { // <= 0 on barrier 2265 level = current->td_level; 2266 kmp_taskdata_t *parent = taskdata->td_parent; 2267 while (parent != current && parent->td_level > level) { 2268 parent = parent->td_parent; // check generation up to the level of the 2269 // current task 2270 KMP_DEBUG_ASSERT(parent != NULL); 2271 } 2272 if (parent != current) { 2273 if (!task_team->tt.tt_untied_task_encountered) { 2274 // The TSC does not allow to steal victim task 2275 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2276 KA_TRACE(10, 2277 ("__kmp_steal_task(exit #3): T#%d could not steal from " 2278 "T#%d: task_team=%p ntasks=%d head=%u tail=%u\n", 2279 gtid, __kmp_gtid_from_thread(victim_thr), task_team, ntasks, 2280 victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2281 return NULL; 2282 } 2283 taskdata = NULL; // will check other tasks in victim's deque 2284 } 2285 } 2286 } 2287 if (taskdata != NULL) { 2288 // Bump head pointer and Wrap. 2289 victim_td->td.td_deque_head = 2290 (victim_td->td.td_deque_head + 1) & TASK_DEQUE_MASK(victim_td->td); 2291 } else { 2292 int i; 2293 // walk through victim's deque trying to steal any task 2294 target = victim_td->td.td_deque_head; 2295 for (i = 1; i < ntasks; ++i) { 2296 target = (target + 1) & TASK_DEQUE_MASK(victim_td->td); 2297 taskdata = victim_td->td.td_deque[target]; 2298 if (taskdata->td_flags.tiedness == TASK_TIED) { 2299 // check if the candidate obeys the TSC 2300 kmp_taskdata_t *parent = taskdata->td_parent; 2301 // check generation up to the level of the current task 2302 while (parent != current && parent->td_level > level) { 2303 parent = parent->td_parent; 2304 KMP_DEBUG_ASSERT(parent != NULL); 2305 } 2306 if (parent != current) { 2307 // The TSC does not allow to steal the candidate 2308 taskdata = NULL; 2309 continue; 2310 } else { 2311 // found victim tied task 2312 break; 2313 } 2314 } else { 2315 // found victim untied task 2316 break; 2317 } 2318 } 2319 if (taskdata == NULL) { 2320 // No appropriate candidate to steal found 2321 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2322 KA_TRACE(10, ("__kmp_steal_task(exit #4): T#%d could not steal from " 2323 "T#%d: task_team=%p ntasks=%d head=%u tail=%u\n", 2324 gtid, __kmp_gtid_from_thread(victim_thr), task_team, ntasks, 2325 victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2326 return NULL; 2327 } 2328 int prev = target; 2329 for (i = i + 1; i < ntasks; ++i) { 2330 // shift remaining tasks in the deque left by 1 2331 target = (target + 1) & TASK_DEQUE_MASK(victim_td->td); 2332 victim_td->td.td_deque[prev] = victim_td->td.td_deque[target]; 2333 prev = target; 2334 } 2335 KMP_DEBUG_ASSERT(victim_td->td.td_deque_tail == 2336 ((target + 1) & TASK_DEQUE_MASK(victim_td->td))); 2337 victim_td->td.td_deque_tail = target; // tail -= 1 (wrapped)) 2338 } 2339 if (*thread_finished) { 2340 // We need to un-mark this victim as a finished victim. This must be done 2341 // before releasing the lock, or else other threads (starting with the 2342 // master victim) might be prematurely released from the barrier!!! 2343 kmp_int32 count; 2344 2345 count = KMP_TEST_THEN_INC32(unfinished_threads); 2346 2347 KA_TRACE( 2348 20, 2349 ("__kmp_steal_task: T#%d inc unfinished_threads to %d: task_team=%p\n", 2350 gtid, count + 1, task_team)); 2351 2352 *thread_finished = FALSE; 2353 } 2354 TCW_4(victim_td->td.td_deque_ntasks, ntasks - 1); 2355 2356 __kmp_release_bootstrap_lock(&victim_td->td.td_deque_lock); 2357 2358 KMP_COUNT_BLOCK(TASK_stolen); 2359 KA_TRACE(10, 2360 ("__kmp_steal_task(exit #5): T#%d stole task %p from T#%d: " 2361 "task_team=%p ntasks=%d head=%u tail=%u\n", 2362 gtid, taskdata, __kmp_gtid_from_thread(victim_thr), task_team, 2363 ntasks, victim_td->td.td_deque_head, victim_td->td.td_deque_tail)); 2364 2365 task = KMP_TASKDATA_TO_TASK(taskdata); 2366 return task; 2367 } 2368 2369 // __kmp_execute_tasks_template: Choose and execute tasks until either the 2370 // condition is statisfied (return true) or there are none left (return false). 2371 // 2372 // final_spin is TRUE if this is the spin at the release barrier. 2373 // thread_finished indicates whether the thread is finished executing all 2374 // the tasks it has on its deque, and is at the release barrier. 2375 // spinner is the location on which to spin. 2376 // spinner == NULL means only execute a single task and return. 2377 // checker is the value to check to terminate the spin. 2378 template <class C> 2379 static inline int __kmp_execute_tasks_template( 2380 kmp_info_t *thread, kmp_int32 gtid, C *flag, int final_spin, 2381 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2382 kmp_int32 is_constrained) { 2383 kmp_task_team_t *task_team = thread->th.th_task_team; 2384 kmp_thread_data_t *threads_data; 2385 kmp_task_t *task; 2386 kmp_info_t *other_thread; 2387 kmp_taskdata_t *current_task = thread->th.th_current_task; 2388 volatile kmp_int32 *unfinished_threads; 2389 kmp_int32 nthreads, victim_tid = -2, use_own_tasks = 1, new_victim = 0, 2390 tid = thread->th.th_info.ds.ds_tid; 2391 2392 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 2393 KMP_DEBUG_ASSERT(thread == __kmp_threads[gtid]); 2394 2395 if (task_team == NULL) 2396 return FALSE; 2397 2398 KA_TRACE(15, ("__kmp_execute_tasks_template(enter): T#%d final_spin=%d " 2399 "*thread_finished=%d\n", 2400 gtid, final_spin, *thread_finished)); 2401 2402 thread->th.th_reap_state = KMP_NOT_SAFE_TO_REAP; 2403 threads_data = (kmp_thread_data_t *)TCR_PTR(task_team->tt.tt_threads_data); 2404 KMP_DEBUG_ASSERT(threads_data != NULL); 2405 2406 nthreads = task_team->tt.tt_nproc; 2407 unfinished_threads = &(task_team->tt.tt_unfinished_threads); 2408 #if OMP_45_ENABLED 2409 KMP_DEBUG_ASSERT(nthreads > 1 || task_team->tt.tt_found_proxy_tasks); 2410 #else 2411 KMP_DEBUG_ASSERT(nthreads > 1); 2412 #endif 2413 KMP_DEBUG_ASSERT(TCR_4(*unfinished_threads) >= 0); 2414 2415 while (1) { // Outer loop keeps trying to find tasks in case of single thread 2416 // getting tasks from target constructs 2417 while (1) { // Inner loop to find a task and execute it 2418 task = NULL; 2419 if (use_own_tasks) { // check on own queue first 2420 task = __kmp_remove_my_task(thread, gtid, task_team, is_constrained); 2421 } 2422 if ((task == NULL) && (nthreads > 1)) { // Steal a task 2423 int asleep = 1; 2424 use_own_tasks = 0; 2425 // Try to steal from the last place I stole from successfully. 2426 if (victim_tid == -2) { // haven't stolen anything yet 2427 victim_tid = threads_data[tid].td.td_deque_last_stolen; 2428 if (victim_tid != 2429 -1) // if we have a last stolen from victim, get the thread 2430 other_thread = threads_data[victim_tid].td.td_thr; 2431 } 2432 if (victim_tid != -1) { // found last victim 2433 asleep = 0; 2434 } else if (!new_victim) { // no recent steals and we haven't already 2435 // used a new victim; select a random thread 2436 do { // Find a different thread to steal work from. 2437 // Pick a random thread. Initial plan was to cycle through all the 2438 // threads, and only return if we tried to steal from every thread, 2439 // and failed. Arch says that's not such a great idea. 2440 victim_tid = __kmp_get_random(thread) % (nthreads - 1); 2441 if (victim_tid >= tid) { 2442 ++victim_tid; // Adjusts random distribution to exclude self 2443 } 2444 // Found a potential victim 2445 other_thread = threads_data[victim_tid].td.td_thr; 2446 // There is a slight chance that __kmp_enable_tasking() did not wake 2447 // up all threads waiting at the barrier. If victim is sleeping, 2448 // then wake it up. Since we were going to pay the cache miss 2449 // penalty for referencing another thread's kmp_info_t struct 2450 // anyway, 2451 // the check shouldn't cost too much performance at this point. In 2452 // extra barrier mode, tasks do not sleep at the separate tasking 2453 // barrier, so this isn't a problem. 2454 asleep = 0; 2455 if ((__kmp_tasking_mode == tskm_task_teams) && 2456 (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME) && 2457 (TCR_PTR(CCAST(void *, other_thread->th.th_sleep_loc)) != 2458 NULL)) { 2459 asleep = 1; 2460 __kmp_null_resume_wrapper(__kmp_gtid_from_thread(other_thread), 2461 other_thread->th.th_sleep_loc); 2462 // A sleeping thread should not have any tasks on it's queue. 2463 // There is a slight possibility that it resumes, steals a task 2464 // from another thread, which spawns more tasks, all in the time 2465 // that it takes this thread to check => don't write an assertion 2466 // that the victim's queue is empty. Try stealing from a 2467 // different thread. 2468 } 2469 } while (asleep); 2470 } 2471 2472 if (!asleep) { 2473 // We have a victim to try to steal from 2474 task = __kmp_steal_task(other_thread, gtid, task_team, 2475 unfinished_threads, thread_finished, 2476 is_constrained); 2477 } 2478 if (task != NULL) { // set last stolen to victim 2479 if (threads_data[tid].td.td_deque_last_stolen != victim_tid) { 2480 threads_data[tid].td.td_deque_last_stolen = victim_tid; 2481 // The pre-refactored code did not try more than 1 successful new 2482 // vicitm, unless the last one generated more local tasks; 2483 // new_victim keeps track of this 2484 new_victim = 1; 2485 } 2486 } else { // No tasks found; unset last_stolen 2487 KMP_CHECK_UPDATE(threads_data[tid].td.td_deque_last_stolen, -1); 2488 victim_tid = -2; // no successful victim found 2489 } 2490 } 2491 2492 if (task == NULL) // break out of tasking loop 2493 break; 2494 2495 // Found a task; execute it 2496 #if USE_ITT_BUILD && USE_ITT_NOTIFY 2497 if (__itt_sync_create_ptr || KMP_ITT_DEBUG) { 2498 if (itt_sync_obj == NULL) { // we are at fork barrier where we could not 2499 // get the object reliably 2500 itt_sync_obj = __kmp_itt_barrier_object(gtid, bs_forkjoin_barrier); 2501 } 2502 __kmp_itt_task_starting(itt_sync_obj); 2503 } 2504 #endif /* USE_ITT_BUILD && USE_ITT_NOTIFY */ 2505 __kmp_invoke_task(gtid, task, current_task); 2506 #if USE_ITT_BUILD 2507 if (itt_sync_obj != NULL) 2508 __kmp_itt_task_finished(itt_sync_obj); 2509 #endif /* USE_ITT_BUILD */ 2510 // If this thread is only partway through the barrier and the condition is 2511 // met, then return now, so that the barrier gather/release pattern can 2512 // proceed. If this thread is in the last spin loop in the barrier, 2513 // waiting to be released, we know that the termination condition will not 2514 // be satisified, so don't waste any cycles checking it. 2515 if (flag == NULL || (!final_spin && flag->done_check())) { 2516 KA_TRACE( 2517 15, 2518 ("__kmp_execute_tasks_template: T#%d spin condition satisfied\n", 2519 gtid)); 2520 return TRUE; 2521 } 2522 if (thread->th.th_task_team == NULL) { 2523 break; 2524 } 2525 // Yield before executing next task 2526 KMP_YIELD(__kmp_library == library_throughput); 2527 // If execution of a stolen task results in more tasks being placed on our 2528 // run queue, reset use_own_tasks 2529 if (!use_own_tasks && TCR_4(threads_data[tid].td.td_deque_ntasks) != 0) { 2530 KA_TRACE(20, ("__kmp_execute_tasks_template: T#%d stolen task spawned " 2531 "other tasks, restart\n", 2532 gtid)); 2533 use_own_tasks = 1; 2534 new_victim = 0; 2535 } 2536 } 2537 2538 // The task source has been exhausted. If in final spin loop of barrier, check 2539 // if termination condition is satisfied. 2540 #if OMP_45_ENABLED 2541 // The work queue may be empty but there might be proxy tasks still 2542 // executing 2543 if (final_spin && TCR_4(current_task->td_incomplete_child_tasks) == 0) 2544 #else 2545 if (final_spin) 2546 #endif 2547 { 2548 // First, decrement the #unfinished threads, if that has not already been 2549 // done. This decrement might be to the spin location, and result in the 2550 // termination condition being satisfied. 2551 if (!*thread_finished) { 2552 kmp_int32 count; 2553 2554 count = KMP_TEST_THEN_DEC32(unfinished_threads) - 1; 2555 KA_TRACE(20, ("__kmp_execute_tasks_template: T#%d dec " 2556 "unfinished_threads to %d task_team=%p\n", 2557 gtid, count, task_team)); 2558 *thread_finished = TRUE; 2559 } 2560 2561 // It is now unsafe to reference thread->th.th_team !!! 2562 // Decrementing task_team->tt.tt_unfinished_threads can allow the master 2563 // thread to pass through the barrier, where it might reset each thread's 2564 // th.th_team field for the next parallel region. If we can steal more 2565 // work, we know that this has not happened yet. 2566 if (flag != NULL && flag->done_check()) { 2567 KA_TRACE( 2568 15, 2569 ("__kmp_execute_tasks_template: T#%d spin condition satisfied\n", 2570 gtid)); 2571 return TRUE; 2572 } 2573 } 2574 2575 // If this thread's task team is NULL, master has recognized that there are 2576 // no more tasks; bail out 2577 if (thread->th.th_task_team == NULL) { 2578 KA_TRACE(15, 2579 ("__kmp_execute_tasks_template: T#%d no more tasks\n", gtid)); 2580 return FALSE; 2581 } 2582 2583 #if OMP_45_ENABLED 2584 // We could be getting tasks from target constructs; if this is the only 2585 // thread, keep trying to execute tasks from own queue 2586 if (nthreads == 1) 2587 use_own_tasks = 1; 2588 else 2589 #endif 2590 { 2591 KA_TRACE(15, 2592 ("__kmp_execute_tasks_template: T#%d can't find work\n", gtid)); 2593 return FALSE; 2594 } 2595 } 2596 } 2597 2598 int __kmp_execute_tasks_32( 2599 kmp_info_t *thread, kmp_int32 gtid, kmp_flag_32 *flag, int final_spin, 2600 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2601 kmp_int32 is_constrained) { 2602 return __kmp_execute_tasks_template( 2603 thread, gtid, flag, final_spin, 2604 thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), is_constrained); 2605 } 2606 2607 int __kmp_execute_tasks_64( 2608 kmp_info_t *thread, kmp_int32 gtid, kmp_flag_64 *flag, int final_spin, 2609 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2610 kmp_int32 is_constrained) { 2611 return __kmp_execute_tasks_template( 2612 thread, gtid, flag, final_spin, 2613 thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), is_constrained); 2614 } 2615 2616 int __kmp_execute_tasks_oncore( 2617 kmp_info_t *thread, kmp_int32 gtid, kmp_flag_oncore *flag, int final_spin, 2618 int *thread_finished USE_ITT_BUILD_ARG(void *itt_sync_obj), 2619 kmp_int32 is_constrained) { 2620 return __kmp_execute_tasks_template( 2621 thread, gtid, flag, final_spin, 2622 thread_finished USE_ITT_BUILD_ARG(itt_sync_obj), is_constrained); 2623 } 2624 2625 // __kmp_enable_tasking: Allocate task team and resume threads sleeping at the 2626 // next barrier so they can assist in executing enqueued tasks. 2627 // First thread in allocates the task team atomically. 2628 static void __kmp_enable_tasking(kmp_task_team_t *task_team, 2629 kmp_info_t *this_thr) { 2630 kmp_thread_data_t *threads_data; 2631 int nthreads, i, is_init_thread; 2632 2633 KA_TRACE(10, ("__kmp_enable_tasking(enter): T#%d\n", 2634 __kmp_gtid_from_thread(this_thr))); 2635 2636 KMP_DEBUG_ASSERT(task_team != NULL); 2637 KMP_DEBUG_ASSERT(this_thr->th.th_team != NULL); 2638 2639 nthreads = task_team->tt.tt_nproc; 2640 KMP_DEBUG_ASSERT(nthreads > 0); 2641 KMP_DEBUG_ASSERT(nthreads == this_thr->th.th_team->t.t_nproc); 2642 2643 // Allocate or increase the size of threads_data if necessary 2644 is_init_thread = __kmp_realloc_task_threads_data(this_thr, task_team); 2645 2646 if (!is_init_thread) { 2647 // Some other thread already set up the array. 2648 KA_TRACE( 2649 20, 2650 ("__kmp_enable_tasking(exit): T#%d: threads array already set up.\n", 2651 __kmp_gtid_from_thread(this_thr))); 2652 return; 2653 } 2654 threads_data = (kmp_thread_data_t *)TCR_PTR(task_team->tt.tt_threads_data); 2655 KMP_DEBUG_ASSERT(threads_data != NULL); 2656 2657 if ((__kmp_tasking_mode == tskm_task_teams) && 2658 (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME)) { 2659 // Release any threads sleeping at the barrier, so that they can steal 2660 // tasks and execute them. In extra barrier mode, tasks do not sleep 2661 // at the separate tasking barrier, so this isn't a problem. 2662 for (i = 0; i < nthreads; i++) { 2663 volatile void *sleep_loc; 2664 kmp_info_t *thread = threads_data[i].td.td_thr; 2665 2666 if (i == this_thr->th.th_info.ds.ds_tid) { 2667 continue; 2668 } 2669 // Since we haven't locked the thread's suspend mutex lock at this 2670 // point, there is a small window where a thread might be putting 2671 // itself to sleep, but hasn't set the th_sleep_loc field yet. 2672 // To work around this, __kmp_execute_tasks_template() periodically checks 2673 // see if other threads are sleeping (using the same random mechanism that 2674 // is used for task stealing) and awakens them if they are. 2675 if ((sleep_loc = TCR_PTR(CCAST(void *, thread->th.th_sleep_loc))) != 2676 NULL) { 2677 KF_TRACE(50, ("__kmp_enable_tasking: T#%d waking up thread T#%d\n", 2678 __kmp_gtid_from_thread(this_thr), 2679 __kmp_gtid_from_thread(thread))); 2680 __kmp_null_resume_wrapper(__kmp_gtid_from_thread(thread), sleep_loc); 2681 } else { 2682 KF_TRACE(50, ("__kmp_enable_tasking: T#%d don't wake up thread T#%d\n", 2683 __kmp_gtid_from_thread(this_thr), 2684 __kmp_gtid_from_thread(thread))); 2685 } 2686 } 2687 } 2688 2689 KA_TRACE(10, ("__kmp_enable_tasking(exit): T#%d\n", 2690 __kmp_gtid_from_thread(this_thr))); 2691 } 2692 2693 /* // TODO: Check the comment consistency 2694 * Utility routines for "task teams". A task team (kmp_task_t) is kind of 2695 * like a shadow of the kmp_team_t data struct, with a different lifetime. 2696 * After a child * thread checks into a barrier and calls __kmp_release() from 2697 * the particular variant of __kmp_<barrier_kind>_barrier_gather(), it can no 2698 * longer assume that the kmp_team_t structure is intact (at any moment, the 2699 * master thread may exit the barrier code and free the team data structure, 2700 * and return the threads to the thread pool). 2701 * 2702 * This does not work with the the tasking code, as the thread is still 2703 * expected to participate in the execution of any tasks that may have been 2704 * spawned my a member of the team, and the thread still needs access to all 2705 * to each thread in the team, so that it can steal work from it. 2706 * 2707 * Enter the existence of the kmp_task_team_t struct. It employs a reference 2708 * counting mechanims, and is allocated by the master thread before calling 2709 * __kmp_<barrier_kind>_release, and then is release by the last thread to 2710 * exit __kmp_<barrier_kind>_release at the next barrier. I.e. the lifetimes 2711 * of the kmp_task_team_t structs for consecutive barriers can overlap 2712 * (and will, unless the master thread is the last thread to exit the barrier 2713 * release phase, which is not typical). 2714 * 2715 * The existence of such a struct is useful outside the context of tasking, 2716 * but for now, I'm trying to keep it specific to the OMP_30_ENABLED macro, 2717 * so that any performance differences show up when comparing the 2.5 vs. 3.0 2718 * libraries. 2719 * 2720 * We currently use the existence of the threads array as an indicator that 2721 * tasks were spawned since the last barrier. If the structure is to be 2722 * useful outside the context of tasking, then this will have to change, but 2723 * not settting the field minimizes the performance impact of tasking on 2724 * barriers, when no explicit tasks were spawned (pushed, actually). 2725 */ 2726 2727 static kmp_task_team_t *__kmp_free_task_teams = 2728 NULL; // Free list for task_team data structures 2729 // Lock for task team data structures 2730 static kmp_bootstrap_lock_t __kmp_task_team_lock = 2731 KMP_BOOTSTRAP_LOCK_INITIALIZER(__kmp_task_team_lock); 2732 2733 // __kmp_alloc_task_deque: 2734 // Allocates a task deque for a particular thread, and initialize the necessary 2735 // data structures relating to the deque. This only happens once per thread 2736 // per task team since task teams are recycled. No lock is needed during 2737 // allocation since each thread allocates its own deque. 2738 static void __kmp_alloc_task_deque(kmp_info_t *thread, 2739 kmp_thread_data_t *thread_data) { 2740 __kmp_init_bootstrap_lock(&thread_data->td.td_deque_lock); 2741 KMP_DEBUG_ASSERT(thread_data->td.td_deque == NULL); 2742 2743 // Initialize last stolen task field to "none" 2744 thread_data->td.td_deque_last_stolen = -1; 2745 2746 KMP_DEBUG_ASSERT(TCR_4(thread_data->td.td_deque_ntasks) == 0); 2747 KMP_DEBUG_ASSERT(thread_data->td.td_deque_head == 0); 2748 KMP_DEBUG_ASSERT(thread_data->td.td_deque_tail == 0); 2749 2750 KE_TRACE( 2751 10, 2752 ("__kmp_alloc_task_deque: T#%d allocating deque[%d] for thread_data %p\n", 2753 __kmp_gtid_from_thread(thread), INITIAL_TASK_DEQUE_SIZE, thread_data)); 2754 // Allocate space for task deque, and zero the deque 2755 // Cannot use __kmp_thread_calloc() because threads not around for 2756 // kmp_reap_task_team( ). 2757 thread_data->td.td_deque = (kmp_taskdata_t **)__kmp_allocate( 2758 INITIAL_TASK_DEQUE_SIZE * sizeof(kmp_taskdata_t *)); 2759 thread_data->td.td_deque_size = INITIAL_TASK_DEQUE_SIZE; 2760 } 2761 2762 // __kmp_realloc_task_deque: 2763 // Re-allocates a task deque for a particular thread, copies the content from 2764 // the old deque and adjusts the necessary data structures relating to the 2765 // deque. This operation must be done with a the deque_lock being held 2766 static void __kmp_realloc_task_deque(kmp_info_t *thread, 2767 kmp_thread_data_t *thread_data) { 2768 kmp_int32 size = TASK_DEQUE_SIZE(thread_data->td); 2769 kmp_int32 new_size = 2 * size; 2770 2771 KE_TRACE(10, ("__kmp_realloc_task_deque: T#%d reallocating deque[from %d to " 2772 "%d] for thread_data %p\n", 2773 __kmp_gtid_from_thread(thread), size, new_size, thread_data)); 2774 2775 kmp_taskdata_t **new_deque = 2776 (kmp_taskdata_t **)__kmp_allocate(new_size * sizeof(kmp_taskdata_t *)); 2777 2778 int i, j; 2779 for (i = thread_data->td.td_deque_head, j = 0; j < size; 2780 i = (i + 1) & TASK_DEQUE_MASK(thread_data->td), j++) 2781 new_deque[j] = thread_data->td.td_deque[i]; 2782 2783 __kmp_free(thread_data->td.td_deque); 2784 2785 thread_data->td.td_deque_head = 0; 2786 thread_data->td.td_deque_tail = size; 2787 thread_data->td.td_deque = new_deque; 2788 thread_data->td.td_deque_size = new_size; 2789 } 2790 2791 // __kmp_free_task_deque: 2792 // Deallocates a task deque for a particular thread. Happens at library 2793 // deallocation so don't need to reset all thread data fields. 2794 static void __kmp_free_task_deque(kmp_thread_data_t *thread_data) { 2795 if (thread_data->td.td_deque != NULL) { 2796 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 2797 TCW_4(thread_data->td.td_deque_ntasks, 0); 2798 __kmp_free(thread_data->td.td_deque); 2799 thread_data->td.td_deque = NULL; 2800 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 2801 } 2802 2803 #ifdef BUILD_TIED_TASK_STACK 2804 // GEH: Figure out what to do here for td_susp_tied_tasks 2805 if (thread_data->td.td_susp_tied_tasks.ts_entries != TASK_STACK_EMPTY) { 2806 __kmp_free_task_stack(__kmp_thread_from_gtid(gtid), thread_data); 2807 } 2808 #endif // BUILD_TIED_TASK_STACK 2809 } 2810 2811 // __kmp_realloc_task_threads_data: 2812 // Allocates a threads_data array for a task team, either by allocating an 2813 // initial array or enlarging an existing array. Only the first thread to get 2814 // the lock allocs or enlarges the array and re-initializes the array eleemnts. 2815 // That thread returns "TRUE", the rest return "FALSE". 2816 // Assumes that the new array size is given by task_team -> tt.tt_nproc. 2817 // The current size is given by task_team -> tt.tt_max_threads. 2818 static int __kmp_realloc_task_threads_data(kmp_info_t *thread, 2819 kmp_task_team_t *task_team) { 2820 kmp_thread_data_t **threads_data_p; 2821 kmp_int32 nthreads, maxthreads; 2822 int is_init_thread = FALSE; 2823 2824 if (TCR_4(task_team->tt.tt_found_tasks)) { 2825 // Already reallocated and initialized. 2826 return FALSE; 2827 } 2828 2829 threads_data_p = &task_team->tt.tt_threads_data; 2830 nthreads = task_team->tt.tt_nproc; 2831 maxthreads = task_team->tt.tt_max_threads; 2832 2833 // All threads must lock when they encounter the first task of the implicit 2834 // task region to make sure threads_data fields are (re)initialized before 2835 // used. 2836 __kmp_acquire_bootstrap_lock(&task_team->tt.tt_threads_lock); 2837 2838 if (!TCR_4(task_team->tt.tt_found_tasks)) { 2839 // first thread to enable tasking 2840 kmp_team_t *team = thread->th.th_team; 2841 int i; 2842 2843 is_init_thread = TRUE; 2844 if (maxthreads < nthreads) { 2845 2846 if (*threads_data_p != NULL) { 2847 kmp_thread_data_t *old_data = *threads_data_p; 2848 kmp_thread_data_t *new_data = NULL; 2849 2850 KE_TRACE( 2851 10, 2852 ("__kmp_realloc_task_threads_data: T#%d reallocating " 2853 "threads data for task_team %p, new_size = %d, old_size = %d\n", 2854 __kmp_gtid_from_thread(thread), task_team, nthreads, maxthreads)); 2855 // Reallocate threads_data to have more elements than current array 2856 // Cannot use __kmp_thread_realloc() because threads not around for 2857 // kmp_reap_task_team( ). Note all new array entries are initialized 2858 // to zero by __kmp_allocate(). 2859 new_data = (kmp_thread_data_t *)__kmp_allocate( 2860 nthreads * sizeof(kmp_thread_data_t)); 2861 // copy old data to new data 2862 KMP_MEMCPY_S((void *)new_data, nthreads * sizeof(kmp_thread_data_t), 2863 (void *)old_data, maxthreads * sizeof(kmp_thread_data_t)); 2864 2865 #ifdef BUILD_TIED_TASK_STACK 2866 // GEH: Figure out if this is the right thing to do 2867 for (i = maxthreads; i < nthreads; i++) { 2868 kmp_thread_data_t *thread_data = &(*threads_data_p)[i]; 2869 __kmp_init_task_stack(__kmp_gtid_from_thread(thread), thread_data); 2870 } 2871 #endif // BUILD_TIED_TASK_STACK 2872 // Install the new data and free the old data 2873 (*threads_data_p) = new_data; 2874 __kmp_free(old_data); 2875 } else { 2876 KE_TRACE(10, ("__kmp_realloc_task_threads_data: T#%d allocating " 2877 "threads data for task_team %p, size = %d\n", 2878 __kmp_gtid_from_thread(thread), task_team, nthreads)); 2879 // Make the initial allocate for threads_data array, and zero entries 2880 // Cannot use __kmp_thread_calloc() because threads not around for 2881 // kmp_reap_task_team( ). 2882 ANNOTATE_IGNORE_WRITES_BEGIN(); 2883 *threads_data_p = (kmp_thread_data_t *)__kmp_allocate( 2884 nthreads * sizeof(kmp_thread_data_t)); 2885 ANNOTATE_IGNORE_WRITES_END(); 2886 #ifdef BUILD_TIED_TASK_STACK 2887 // GEH: Figure out if this is the right thing to do 2888 for (i = 0; i < nthreads; i++) { 2889 kmp_thread_data_t *thread_data = &(*threads_data_p)[i]; 2890 __kmp_init_task_stack(__kmp_gtid_from_thread(thread), thread_data); 2891 } 2892 #endif // BUILD_TIED_TASK_STACK 2893 } 2894 task_team->tt.tt_max_threads = nthreads; 2895 } else { 2896 // If array has (more than) enough elements, go ahead and use it 2897 KMP_DEBUG_ASSERT(*threads_data_p != NULL); 2898 } 2899 2900 // initialize threads_data pointers back to thread_info structures 2901 for (i = 0; i < nthreads; i++) { 2902 kmp_thread_data_t *thread_data = &(*threads_data_p)[i]; 2903 thread_data->td.td_thr = team->t.t_threads[i]; 2904 2905 if (thread_data->td.td_deque_last_stolen >= nthreads) { 2906 // The last stolen field survives across teams / barrier, and the number 2907 // of threads may have changed. It's possible (likely?) that a new 2908 // parallel region will exhibit the same behavior as previous region. 2909 thread_data->td.td_deque_last_stolen = -1; 2910 } 2911 } 2912 2913 KMP_MB(); 2914 TCW_SYNC_4(task_team->tt.tt_found_tasks, TRUE); 2915 } 2916 2917 __kmp_release_bootstrap_lock(&task_team->tt.tt_threads_lock); 2918 return is_init_thread; 2919 } 2920 2921 // __kmp_free_task_threads_data: 2922 // Deallocates a threads_data array for a task team, including any attached 2923 // tasking deques. Only occurs at library shutdown. 2924 static void __kmp_free_task_threads_data(kmp_task_team_t *task_team) { 2925 __kmp_acquire_bootstrap_lock(&task_team->tt.tt_threads_lock); 2926 if (task_team->tt.tt_threads_data != NULL) { 2927 int i; 2928 for (i = 0; i < task_team->tt.tt_max_threads; i++) { 2929 __kmp_free_task_deque(&task_team->tt.tt_threads_data[i]); 2930 } 2931 __kmp_free(task_team->tt.tt_threads_data); 2932 task_team->tt.tt_threads_data = NULL; 2933 } 2934 __kmp_release_bootstrap_lock(&task_team->tt.tt_threads_lock); 2935 } 2936 2937 // __kmp_allocate_task_team: 2938 // Allocates a task team associated with a specific team, taking it from 2939 // the global task team free list if possible. Also initializes data 2940 // structures. 2941 static kmp_task_team_t *__kmp_allocate_task_team(kmp_info_t *thread, 2942 kmp_team_t *team) { 2943 kmp_task_team_t *task_team = NULL; 2944 int nthreads; 2945 2946 KA_TRACE(20, ("__kmp_allocate_task_team: T#%d entering; team = %p\n", 2947 (thread ? __kmp_gtid_from_thread(thread) : -1), team)); 2948 2949 if (TCR_PTR(__kmp_free_task_teams) != NULL) { 2950 // Take a task team from the task team pool 2951 __kmp_acquire_bootstrap_lock(&__kmp_task_team_lock); 2952 if (__kmp_free_task_teams != NULL) { 2953 task_team = __kmp_free_task_teams; 2954 TCW_PTR(__kmp_free_task_teams, task_team->tt.tt_next); 2955 task_team->tt.tt_next = NULL; 2956 } 2957 __kmp_release_bootstrap_lock(&__kmp_task_team_lock); 2958 } 2959 2960 if (task_team == NULL) { 2961 KE_TRACE(10, ("__kmp_allocate_task_team: T#%d allocating " 2962 "task team for team %p\n", 2963 __kmp_gtid_from_thread(thread), team)); 2964 // Allocate a new task team if one is not available. 2965 // Cannot use __kmp_thread_malloc() because threads not around for 2966 // kmp_reap_task_team( ). 2967 task_team = (kmp_task_team_t *)__kmp_allocate(sizeof(kmp_task_team_t)); 2968 __kmp_init_bootstrap_lock(&task_team->tt.tt_threads_lock); 2969 // AC: __kmp_allocate zeroes returned memory 2970 // task_team -> tt.tt_threads_data = NULL; 2971 // task_team -> tt.tt_max_threads = 0; 2972 // task_team -> tt.tt_next = NULL; 2973 } 2974 2975 TCW_4(task_team->tt.tt_found_tasks, FALSE); 2976 #if OMP_45_ENABLED 2977 TCW_4(task_team->tt.tt_found_proxy_tasks, FALSE); 2978 #endif 2979 task_team->tt.tt_nproc = nthreads = team->t.t_nproc; 2980 2981 TCW_4(task_team->tt.tt_unfinished_threads, nthreads); 2982 TCW_4(task_team->tt.tt_active, TRUE); 2983 2984 KA_TRACE(20, ("__kmp_allocate_task_team: T#%d exiting; task_team = %p " 2985 "unfinished_threads init'd to %d\n", 2986 (thread ? __kmp_gtid_from_thread(thread) : -1), task_team, 2987 task_team->tt.tt_unfinished_threads)); 2988 return task_team; 2989 } 2990 2991 // __kmp_free_task_team: 2992 // Frees the task team associated with a specific thread, and adds it 2993 // to the global task team free list. 2994 void __kmp_free_task_team(kmp_info_t *thread, kmp_task_team_t *task_team) { 2995 KA_TRACE(20, ("__kmp_free_task_team: T#%d task_team = %p\n", 2996 thread ? __kmp_gtid_from_thread(thread) : -1, task_team)); 2997 2998 // Put task team back on free list 2999 __kmp_acquire_bootstrap_lock(&__kmp_task_team_lock); 3000 3001 KMP_DEBUG_ASSERT(task_team->tt.tt_next == NULL); 3002 task_team->tt.tt_next = __kmp_free_task_teams; 3003 TCW_PTR(__kmp_free_task_teams, task_team); 3004 3005 __kmp_release_bootstrap_lock(&__kmp_task_team_lock); 3006 } 3007 3008 // __kmp_reap_task_teams: 3009 // Free all the task teams on the task team free list. 3010 // Should only be done during library shutdown. 3011 // Cannot do anything that needs a thread structure or gtid since they are 3012 // already gone. 3013 void __kmp_reap_task_teams(void) { 3014 kmp_task_team_t *task_team; 3015 3016 if (TCR_PTR(__kmp_free_task_teams) != NULL) { 3017 // Free all task_teams on the free list 3018 __kmp_acquire_bootstrap_lock(&__kmp_task_team_lock); 3019 while ((task_team = __kmp_free_task_teams) != NULL) { 3020 __kmp_free_task_teams = task_team->tt.tt_next; 3021 task_team->tt.tt_next = NULL; 3022 3023 // Free threads_data if necessary 3024 if (task_team->tt.tt_threads_data != NULL) { 3025 __kmp_free_task_threads_data(task_team); 3026 } 3027 __kmp_free(task_team); 3028 } 3029 __kmp_release_bootstrap_lock(&__kmp_task_team_lock); 3030 } 3031 } 3032 3033 // __kmp_wait_to_unref_task_teams: 3034 // Some threads could still be in the fork barrier release code, possibly 3035 // trying to steal tasks. Wait for each thread to unreference its task team. 3036 void __kmp_wait_to_unref_task_teams(void) { 3037 kmp_info_t *thread; 3038 kmp_uint32 spins; 3039 int done; 3040 3041 KMP_INIT_YIELD(spins); 3042 3043 for (;;) { 3044 done = TRUE; 3045 3046 // TODO: GEH - this may be is wrong because some sync would be necessary 3047 // in case threads are added to the pool during the traversal. Need to 3048 // verify that lock for thread pool is held when calling this routine. 3049 for (thread = CCAST(kmp_info_t *, __kmp_thread_pool); thread != NULL; 3050 thread = thread->th.th_next_pool) { 3051 #if KMP_OS_WINDOWS 3052 DWORD exit_val; 3053 #endif 3054 if (TCR_PTR(thread->th.th_task_team) == NULL) { 3055 KA_TRACE(10, ("__kmp_wait_to_unref_task_team: T#%d task_team == NULL\n", 3056 __kmp_gtid_from_thread(thread))); 3057 continue; 3058 } 3059 #if KMP_OS_WINDOWS 3060 // TODO: GEH - add this check for Linux* OS / OS X* as well? 3061 if (!__kmp_is_thread_alive(thread, &exit_val)) { 3062 thread->th.th_task_team = NULL; 3063 continue; 3064 } 3065 #endif 3066 3067 done = FALSE; // Because th_task_team pointer is not NULL for this thread 3068 3069 KA_TRACE(10, ("__kmp_wait_to_unref_task_team: Waiting for T#%d to " 3070 "unreference task_team\n", 3071 __kmp_gtid_from_thread(thread))); 3072 3073 if (__kmp_dflt_blocktime != KMP_MAX_BLOCKTIME) { 3074 volatile void *sleep_loc; 3075 // If the thread is sleeping, awaken it. 3076 if ((sleep_loc = TCR_PTR(CCAST(void *, thread->th.th_sleep_loc))) != 3077 NULL) { 3078 KA_TRACE( 3079 10, 3080 ("__kmp_wait_to_unref_task_team: T#%d waking up thread T#%d\n", 3081 __kmp_gtid_from_thread(thread), __kmp_gtid_from_thread(thread))); 3082 __kmp_null_resume_wrapper(__kmp_gtid_from_thread(thread), sleep_loc); 3083 } 3084 } 3085 } 3086 if (done) { 3087 break; 3088 } 3089 3090 // If we are oversubscribed, or have waited a bit (and library mode is 3091 // throughput), yield. Pause is in the following code. 3092 KMP_YIELD(TCR_4(__kmp_nth) > __kmp_avail_proc); 3093 KMP_YIELD_SPIN(spins); // Yields only if KMP_LIBRARY=throughput 3094 } 3095 } 3096 3097 // __kmp_task_team_setup: Create a task_team for the current team, but use 3098 // an already created, unused one if it already exists. 3099 void __kmp_task_team_setup(kmp_info_t *this_thr, kmp_team_t *team, int always) { 3100 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 3101 3102 // If this task_team hasn't been created yet, allocate it. It will be used in 3103 // the region after the next. 3104 // If it exists, it is the current task team and shouldn't be touched yet as 3105 // it may still be in use. 3106 if (team->t.t_task_team[this_thr->th.th_task_state] == NULL && 3107 (always || team->t.t_nproc > 1)) { 3108 team->t.t_task_team[this_thr->th.th_task_state] = 3109 __kmp_allocate_task_team(this_thr, team); 3110 KA_TRACE(20, ("__kmp_task_team_setup: Master T#%d created new task_team %p " 3111 "for team %d at parity=%d\n", 3112 __kmp_gtid_from_thread(this_thr), 3113 team->t.t_task_team[this_thr->th.th_task_state], 3114 ((team != NULL) ? team->t.t_id : -1), 3115 this_thr->th.th_task_state)); 3116 } 3117 3118 // After threads exit the release, they will call sync, and then point to this 3119 // other task_team; make sure it is allocated and properly initialized. As 3120 // threads spin in the barrier release phase, they will continue to use the 3121 // previous task_team struct(above), until they receive the signal to stop 3122 // checking for tasks (they can't safely reference the kmp_team_t struct, 3123 // which could be reallocated by the master thread). No task teams are formed 3124 // for serialized teams. 3125 if (team->t.t_nproc > 1) { 3126 int other_team = 1 - this_thr->th.th_task_state; 3127 if (team->t.t_task_team[other_team] == NULL) { // setup other team as well 3128 team->t.t_task_team[other_team] = 3129 __kmp_allocate_task_team(this_thr, team); 3130 KA_TRACE(20, ("__kmp_task_team_setup: Master T#%d created second new " 3131 "task_team %p for team %d at parity=%d\n", 3132 __kmp_gtid_from_thread(this_thr), 3133 team->t.t_task_team[other_team], 3134 ((team != NULL) ? team->t.t_id : -1), other_team)); 3135 } else { // Leave the old task team struct in place for the upcoming region; 3136 // adjust as needed 3137 kmp_task_team_t *task_team = team->t.t_task_team[other_team]; 3138 if (!task_team->tt.tt_active || 3139 team->t.t_nproc != task_team->tt.tt_nproc) { 3140 TCW_4(task_team->tt.tt_nproc, team->t.t_nproc); 3141 TCW_4(task_team->tt.tt_found_tasks, FALSE); 3142 #if OMP_45_ENABLED 3143 TCW_4(task_team->tt.tt_found_proxy_tasks, FALSE); 3144 #endif 3145 TCW_4(task_team->tt.tt_unfinished_threads, team->t.t_nproc); 3146 TCW_4(task_team->tt.tt_active, TRUE); 3147 } 3148 // if team size has changed, the first thread to enable tasking will 3149 // realloc threads_data if necessary 3150 KA_TRACE(20, ("__kmp_task_team_setup: Master T#%d reset next task_team " 3151 "%p for team %d at parity=%d\n", 3152 __kmp_gtid_from_thread(this_thr), 3153 team->t.t_task_team[other_team], 3154 ((team != NULL) ? team->t.t_id : -1), other_team)); 3155 } 3156 } 3157 } 3158 3159 // __kmp_task_team_sync: Propagation of task team data from team to threads 3160 // which happens just after the release phase of a team barrier. This may be 3161 // called by any thread, but only for teams with # threads > 1. 3162 void __kmp_task_team_sync(kmp_info_t *this_thr, kmp_team_t *team) { 3163 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 3164 3165 // Toggle the th_task_state field, to switch which task_team this thread 3166 // refers to 3167 this_thr->th.th_task_state = 1 - this_thr->th.th_task_state; 3168 // It is now safe to propagate the task team pointer from the team struct to 3169 // the current thread. 3170 TCW_PTR(this_thr->th.th_task_team, 3171 team->t.t_task_team[this_thr->th.th_task_state]); 3172 KA_TRACE(20, 3173 ("__kmp_task_team_sync: Thread T#%d task team switched to task_team " 3174 "%p from Team #%d (parity=%d)\n", 3175 __kmp_gtid_from_thread(this_thr), this_thr->th.th_task_team, 3176 ((team != NULL) ? team->t.t_id : -1), this_thr->th.th_task_state)); 3177 } 3178 3179 // __kmp_task_team_wait: Master thread waits for outstanding tasks after the 3180 // barrier gather phase. Only called by master thread if #threads in team > 1 or 3181 // if proxy tasks were created. 3182 // 3183 // wait is a flag that defaults to 1 (see kmp.h), but waiting can be turned off 3184 // by passing in 0 optionally as the last argument. When wait is zero, master 3185 // thread does not wait for unfinished_threads to reach 0. 3186 void __kmp_task_team_wait( 3187 kmp_info_t *this_thr, 3188 kmp_team_t *team USE_ITT_BUILD_ARG(void *itt_sync_obj), int wait) { 3189 kmp_task_team_t *task_team = team->t.t_task_team[this_thr->th.th_task_state]; 3190 3191 KMP_DEBUG_ASSERT(__kmp_tasking_mode != tskm_immediate_exec); 3192 KMP_DEBUG_ASSERT(task_team == this_thr->th.th_task_team); 3193 3194 if ((task_team != NULL) && KMP_TASKING_ENABLED(task_team)) { 3195 if (wait) { 3196 KA_TRACE(20, ("__kmp_task_team_wait: Master T#%d waiting for all tasks " 3197 "(for unfinished_threads to reach 0) on task_team = %p\n", 3198 __kmp_gtid_from_thread(this_thr), task_team)); 3199 // Worker threads may have dropped through to release phase, but could 3200 // still be executing tasks. Wait here for tasks to complete. To avoid 3201 // memory contention, only master thread checks termination condition. 3202 kmp_flag_32 flag( 3203 RCAST(volatile kmp_uint32 *, &task_team->tt.tt_unfinished_threads), 3204 0U); 3205 flag.wait(this_thr, TRUE USE_ITT_BUILD_ARG(itt_sync_obj)); 3206 } 3207 // Deactivate the old task team, so that the worker threads will stop 3208 // referencing it while spinning. 3209 KA_TRACE( 3210 20, 3211 ("__kmp_task_team_wait: Master T#%d deactivating task_team %p: " 3212 "setting active to false, setting local and team's pointer to NULL\n", 3213 __kmp_gtid_from_thread(this_thr), task_team)); 3214 #if OMP_45_ENABLED 3215 KMP_DEBUG_ASSERT(task_team->tt.tt_nproc > 1 || 3216 task_team->tt.tt_found_proxy_tasks == TRUE); 3217 TCW_SYNC_4(task_team->tt.tt_found_proxy_tasks, FALSE); 3218 #else 3219 KMP_DEBUG_ASSERT(task_team->tt.tt_nproc > 1); 3220 #endif 3221 KMP_CHECK_UPDATE(task_team->tt.tt_untied_task_encountered, 0); 3222 TCW_SYNC_4(task_team->tt.tt_active, FALSE); 3223 KMP_MB(); 3224 3225 TCW_PTR(this_thr->th.th_task_team, NULL); 3226 } 3227 } 3228 3229 // __kmp_tasking_barrier: 3230 // This routine may only called when __kmp_tasking_mode == tskm_extra_barrier. 3231 // Internal function to execute all tasks prior to a regular barrier or a join 3232 // barrier. It is a full barrier itself, which unfortunately turns regular 3233 // barriers into double barriers and join barriers into 1 1/2 barriers. 3234 void __kmp_tasking_barrier(kmp_team_t *team, kmp_info_t *thread, int gtid) { 3235 volatile kmp_uint32 *spin = RCAST( 3236 volatile kmp_uint32 *, 3237 &team->t.t_task_team[thread->th.th_task_state]->tt.tt_unfinished_threads); 3238 int flag = FALSE; 3239 KMP_DEBUG_ASSERT(__kmp_tasking_mode == tskm_extra_barrier); 3240 3241 #if USE_ITT_BUILD 3242 KMP_FSYNC_SPIN_INIT(spin, (kmp_uint32 *)NULL); 3243 #endif /* USE_ITT_BUILD */ 3244 kmp_flag_32 spin_flag(spin, 0U); 3245 while (!spin_flag.execute_tasks(thread, gtid, TRUE, 3246 &flag USE_ITT_BUILD_ARG(NULL), 0)) { 3247 #if USE_ITT_BUILD 3248 // TODO: What about itt_sync_obj?? 3249 KMP_FSYNC_SPIN_PREPARE(CCAST(kmp_uint32 *, spin)); 3250 #endif /* USE_ITT_BUILD */ 3251 3252 if (TCR_4(__kmp_global.g.g_done)) { 3253 if (__kmp_global.g.g_abort) 3254 __kmp_abort_thread(); 3255 break; 3256 } 3257 KMP_YIELD(TRUE); // GH: We always yield here 3258 } 3259 #if USE_ITT_BUILD 3260 KMP_FSYNC_SPIN_ACQUIRED(CCAST(kmp_uint32 *, spin)); 3261 #endif /* USE_ITT_BUILD */ 3262 } 3263 3264 #if OMP_45_ENABLED 3265 3266 // __kmp_give_task puts a task into a given thread queue if: 3267 // - the queue for that thread was created 3268 // - there's space in that queue 3269 // Because of this, __kmp_push_task needs to check if there's space after 3270 // getting the lock 3271 static bool __kmp_give_task(kmp_info_t *thread, kmp_int32 tid, kmp_task_t *task, 3272 kmp_int32 pass) { 3273 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3274 kmp_task_team_t *task_team = taskdata->td_task_team; 3275 3276 KA_TRACE(20, ("__kmp_give_task: trying to give task %p to thread %d.\n", 3277 taskdata, tid)); 3278 3279 // If task_team is NULL something went really bad... 3280 KMP_DEBUG_ASSERT(task_team != NULL); 3281 3282 bool result = false; 3283 kmp_thread_data_t *thread_data = &task_team->tt.tt_threads_data[tid]; 3284 3285 if (thread_data->td.td_deque == NULL) { 3286 // There's no queue in this thread, go find another one 3287 // We're guaranteed that at least one thread has a queue 3288 KA_TRACE(30, 3289 ("__kmp_give_task: thread %d has no queue while giving task %p.\n", 3290 tid, taskdata)); 3291 return result; 3292 } 3293 3294 if (TCR_4(thread_data->td.td_deque_ntasks) >= 3295 TASK_DEQUE_SIZE(thread_data->td)) { 3296 KA_TRACE( 3297 30, 3298 ("__kmp_give_task: queue is full while giving task %p to thread %d.\n", 3299 taskdata, tid)); 3300 3301 // if this deque is bigger than the pass ratio give a chance to another 3302 // thread 3303 if (TASK_DEQUE_SIZE(thread_data->td) / INITIAL_TASK_DEQUE_SIZE >= pass) 3304 return result; 3305 3306 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 3307 __kmp_realloc_task_deque(thread, thread_data); 3308 3309 } else { 3310 3311 __kmp_acquire_bootstrap_lock(&thread_data->td.td_deque_lock); 3312 3313 if (TCR_4(thread_data->td.td_deque_ntasks) >= 3314 TASK_DEQUE_SIZE(thread_data->td)) { 3315 KA_TRACE(30, ("__kmp_give_task: queue is full while giving task %p to " 3316 "thread %d.\n", 3317 taskdata, tid)); 3318 3319 // if this deque is bigger than the pass ratio give a chance to another 3320 // thread 3321 if (TASK_DEQUE_SIZE(thread_data->td) / INITIAL_TASK_DEQUE_SIZE >= pass) 3322 goto release_and_exit; 3323 3324 __kmp_realloc_task_deque(thread, thread_data); 3325 } 3326 } 3327 3328 // lock is held here, and there is space in the deque 3329 3330 thread_data->td.td_deque[thread_data->td.td_deque_tail] = taskdata; 3331 // Wrap index. 3332 thread_data->td.td_deque_tail = 3333 (thread_data->td.td_deque_tail + 1) & TASK_DEQUE_MASK(thread_data->td); 3334 TCW_4(thread_data->td.td_deque_ntasks, 3335 TCR_4(thread_data->td.td_deque_ntasks) + 1); 3336 3337 result = true; 3338 KA_TRACE(30, ("__kmp_give_task: successfully gave task %p to thread %d.\n", 3339 taskdata, tid)); 3340 3341 release_and_exit: 3342 __kmp_release_bootstrap_lock(&thread_data->td.td_deque_lock); 3343 3344 return result; 3345 } 3346 3347 /* The finish of the proxy tasks is divided in two pieces: 3348 - the top half is the one that can be done from a thread outside the team 3349 - the bottom half must be run from a them within the team 3350 3351 In order to run the bottom half the task gets queued back into one of the 3352 threads of the team. Once the td_incomplete_child_task counter of the parent 3353 is decremented the threads can leave the barriers. So, the bottom half needs 3354 to be queued before the counter is decremented. The top half is therefore 3355 divided in two parts: 3356 - things that can be run before queuing the bottom half 3357 - things that must be run after queuing the bottom half 3358 3359 This creates a second race as the bottom half can free the task before the 3360 second top half is executed. To avoid this we use the 3361 td_incomplete_child_task of the proxy task to synchronize the top and bottom 3362 half. */ 3363 static void __kmp_first_top_half_finish_proxy(kmp_taskdata_t *taskdata) { 3364 KMP_DEBUG_ASSERT(taskdata->td_flags.tasktype == TASK_EXPLICIT); 3365 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3366 KMP_DEBUG_ASSERT(taskdata->td_flags.complete == 0); 3367 KMP_DEBUG_ASSERT(taskdata->td_flags.freed == 0); 3368 3369 taskdata->td_flags.complete = 1; // mark the task as completed 3370 3371 if (taskdata->td_taskgroup) 3372 KMP_TEST_THEN_DEC32(&taskdata->td_taskgroup->count); 3373 3374 // Create an imaginary children for this task so the bottom half cannot 3375 // release the task before we have completed the second top half 3376 TCI_4(taskdata->td_incomplete_child_tasks); 3377 } 3378 3379 static void __kmp_second_top_half_finish_proxy(kmp_taskdata_t *taskdata) { 3380 kmp_int32 children = 0; 3381 3382 // Predecrement simulated by "- 1" calculation 3383 children = 3384 KMP_TEST_THEN_DEC32(&taskdata->td_parent->td_incomplete_child_tasks) - 1; 3385 KMP_DEBUG_ASSERT(children >= 0); 3386 3387 // Remove the imaginary children 3388 TCD_4(taskdata->td_incomplete_child_tasks); 3389 } 3390 3391 static void __kmp_bottom_half_finish_proxy(kmp_int32 gtid, kmp_task_t *ptask) { 3392 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(ptask); 3393 kmp_info_t *thread = __kmp_threads[gtid]; 3394 3395 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3396 KMP_DEBUG_ASSERT(taskdata->td_flags.complete == 3397 1); // top half must run before bottom half 3398 3399 // We need to wait to make sure the top half is finished 3400 // Spinning here should be ok as this should happen quickly 3401 while (TCR_4(taskdata->td_incomplete_child_tasks) > 0) 3402 ; 3403 3404 __kmp_release_deps(gtid, taskdata); 3405 __kmp_free_task_and_ancestors(gtid, taskdata, thread); 3406 } 3407 3408 /*! 3409 @ingroup TASKING 3410 @param gtid Global Thread ID of encountering thread 3411 @param ptask Task which execution is completed 3412 3413 Execute the completation of a proxy task from a thread of that is part of the 3414 team. Run first and bottom halves directly. 3415 */ 3416 void __kmpc_proxy_task_completed(kmp_int32 gtid, kmp_task_t *ptask) { 3417 KMP_DEBUG_ASSERT(ptask != NULL); 3418 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(ptask); 3419 KA_TRACE( 3420 10, ("__kmp_proxy_task_completed(enter): T#%d proxy task %p completing\n", 3421 gtid, taskdata)); 3422 3423 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3424 3425 __kmp_first_top_half_finish_proxy(taskdata); 3426 __kmp_second_top_half_finish_proxy(taskdata); 3427 __kmp_bottom_half_finish_proxy(gtid, ptask); 3428 3429 KA_TRACE(10, 3430 ("__kmp_proxy_task_completed(exit): T#%d proxy task %p completing\n", 3431 gtid, taskdata)); 3432 } 3433 3434 /*! 3435 @ingroup TASKING 3436 @param ptask Task which execution is completed 3437 3438 Execute the completation of a proxy task from a thread that could not belong to 3439 the team. 3440 */ 3441 void __kmpc_proxy_task_completed_ooo(kmp_task_t *ptask) { 3442 KMP_DEBUG_ASSERT(ptask != NULL); 3443 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(ptask); 3444 3445 KA_TRACE( 3446 10, 3447 ("__kmp_proxy_task_completed_ooo(enter): proxy task completing ooo %p\n", 3448 taskdata)); 3449 3450 KMP_DEBUG_ASSERT(taskdata->td_flags.proxy == TASK_PROXY); 3451 3452 __kmp_first_top_half_finish_proxy(taskdata); 3453 3454 // Enqueue task to complete bottom half completion from a thread within the 3455 // corresponding team 3456 kmp_team_t *team = taskdata->td_team; 3457 kmp_int32 nthreads = team->t.t_nproc; 3458 kmp_info_t *thread; 3459 3460 // This should be similar to start_k = __kmp_get_random( thread ) % nthreads 3461 // but we cannot use __kmp_get_random here 3462 kmp_int32 start_k = 0; 3463 kmp_int32 pass = 1; 3464 kmp_int32 k = start_k; 3465 3466 do { 3467 // For now we're just linearly trying to find a thread 3468 thread = team->t.t_threads[k]; 3469 k = (k + 1) % nthreads; 3470 3471 // we did a full pass through all the threads 3472 if (k == start_k) 3473 pass = pass << 1; 3474 3475 } while (!__kmp_give_task(thread, k, ptask, pass)); 3476 3477 __kmp_second_top_half_finish_proxy(taskdata); 3478 3479 KA_TRACE( 3480 10, 3481 ("__kmp_proxy_task_completed_ooo(exit): proxy task completing ooo %p\n", 3482 taskdata)); 3483 } 3484 3485 // __kmp_task_dup_alloc: Allocate the taskdata and make a copy of source task 3486 // for taskloop 3487 // 3488 // thread: allocating thread 3489 // task_src: pointer to source task to be duplicated 3490 // returns: a pointer to the allocated kmp_task_t structure (task). 3491 kmp_task_t *__kmp_task_dup_alloc(kmp_info_t *thread, kmp_task_t *task_src) { 3492 kmp_task_t *task; 3493 kmp_taskdata_t *taskdata; 3494 kmp_taskdata_t *taskdata_src; 3495 kmp_taskdata_t *parent_task = thread->th.th_current_task; 3496 size_t shareds_offset; 3497 size_t task_size; 3498 3499 KA_TRACE(10, ("__kmp_task_dup_alloc(enter): Th %p, source task %p\n", thread, 3500 task_src)); 3501 taskdata_src = KMP_TASK_TO_TASKDATA(task_src); 3502 KMP_DEBUG_ASSERT(taskdata_src->td_flags.proxy == 3503 TASK_FULL); // it should not be proxy task 3504 KMP_DEBUG_ASSERT(taskdata_src->td_flags.tasktype == TASK_EXPLICIT); 3505 task_size = taskdata_src->td_size_alloc; 3506 3507 // Allocate a kmp_taskdata_t block and a kmp_task_t block. 3508 KA_TRACE(30, ("__kmp_task_dup_alloc: Th %p, malloc size %ld\n", thread, 3509 task_size)); 3510 #if USE_FAST_MEMORY 3511 taskdata = (kmp_taskdata_t *)__kmp_fast_allocate(thread, task_size); 3512 #else 3513 taskdata = (kmp_taskdata_t *)__kmp_thread_malloc(thread, task_size); 3514 #endif /* USE_FAST_MEMORY */ 3515 KMP_MEMCPY(taskdata, taskdata_src, task_size); 3516 3517 task = KMP_TASKDATA_TO_TASK(taskdata); 3518 3519 // Initialize new task (only specific fields not affected by memcpy) 3520 taskdata->td_task_id = KMP_GEN_TASK_ID(); 3521 if (task->shareds != NULL) { // need setup shareds pointer 3522 shareds_offset = (char *)task_src->shareds - (char *)taskdata_src; 3523 task->shareds = &((char *)taskdata)[shareds_offset]; 3524 KMP_DEBUG_ASSERT((((kmp_uintptr_t)task->shareds) & (sizeof(void *) - 1)) == 3525 0); 3526 } 3527 taskdata->td_alloc_thread = thread; 3528 taskdata->td_parent = parent_task; 3529 taskdata->td_taskgroup = 3530 parent_task 3531 ->td_taskgroup; // task inherits the taskgroup from the parent task 3532 3533 // Only need to keep track of child task counts if team parallel and tasking 3534 // not serialized 3535 if (!(taskdata->td_flags.team_serial || taskdata->td_flags.tasking_ser)) { 3536 KMP_TEST_THEN_INC32(&parent_task->td_incomplete_child_tasks); 3537 if (parent_task->td_taskgroup) 3538 KMP_TEST_THEN_INC32(&parent_task->td_taskgroup->count); 3539 // Only need to keep track of allocated child tasks for explicit tasks since 3540 // implicit not deallocated 3541 if (taskdata->td_parent->td_flags.tasktype == TASK_EXPLICIT) 3542 KMP_TEST_THEN_INC32(&taskdata->td_parent->td_allocated_child_tasks); 3543 } 3544 3545 KA_TRACE(20, 3546 ("__kmp_task_dup_alloc(exit): Th %p, created task %p, parent=%p\n", 3547 thread, taskdata, taskdata->td_parent)); 3548 #if OMPT_SUPPORT 3549 if (UNLIKELY(ompt_enabled.enabled)) 3550 __ompt_task_init(taskdata, thread->th.th_info.ds.ds_gtid); 3551 #endif 3552 return task; 3553 } 3554 3555 // Routine optionally generated by the compiler for setting the lastprivate flag 3556 // and calling needed constructors for private/firstprivate objects 3557 // (used to form taskloop tasks from pattern task) 3558 // Parameters: dest task, src task, lastprivate flag. 3559 typedef void (*p_task_dup_t)(kmp_task_t *, kmp_task_t *, kmp_int32); 3560 3561 // __kmp_taskloop_linear: Start tasks of the taskloop linearly 3562 // 3563 // loc Source location information 3564 // gtid Global thread ID 3565 // task Pattern task, exposes the loop iteration range 3566 // lb Pointer to loop lower bound in task structure 3567 // ub Pointer to loop upper bound in task structure 3568 // st Loop stride 3569 // ub_glob Global upper bound (used for lastprivate check) 3570 // num_tasks Number of tasks to execute 3571 // grainsize Number of loop iterations per task 3572 // extras Number of chunks with grainsize+1 iterations 3573 // tc Iterations count 3574 // task_dup Tasks duplication routine 3575 void __kmp_taskloop_linear(ident_t *loc, int gtid, kmp_task_t *task, 3576 kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, 3577 kmp_uint64 ub_glob, kmp_uint64 num_tasks, 3578 kmp_uint64 grainsize, kmp_uint64 extras, 3579 kmp_uint64 tc, void *task_dup) { 3580 KMP_COUNT_BLOCK(OMP_TASKLOOP); 3581 KMP_TIME_PARTITIONED_BLOCK(OMP_taskloop_scheduling); 3582 p_task_dup_t ptask_dup = (p_task_dup_t)task_dup; 3583 kmp_uint64 lower = *lb; // compiler provides global bounds here 3584 kmp_uint64 upper = *ub; 3585 kmp_uint64 i; 3586 kmp_info_t *thread = __kmp_threads[gtid]; 3587 kmp_taskdata_t *current_task = thread->th.th_current_task; 3588 kmp_task_t *next_task; 3589 kmp_int32 lastpriv = 0; 3590 size_t lower_offset = 3591 (char *)lb - (char *)task; // remember offset of lb in the task structure 3592 size_t upper_offset = 3593 (char *)ub - (char *)task; // remember offset of ub in the task structure 3594 3595 KMP_DEBUG_ASSERT(tc == num_tasks * grainsize + extras); 3596 KMP_DEBUG_ASSERT(num_tasks > extras); 3597 KMP_DEBUG_ASSERT(num_tasks > 0); 3598 KA_TRACE(20, ("__kmp_taskloop_linear: T#%d: %lld tasks, grainsize %lld, " 3599 "extras %lld, i=%lld,%lld(%d)%lld, dup %p\n", 3600 gtid, num_tasks, grainsize, extras, lower, upper, ub_glob, st, 3601 task_dup)); 3602 3603 // Launch num_tasks tasks, assign grainsize iterations each task 3604 for (i = 0; i < num_tasks; ++i) { 3605 kmp_uint64 chunk_minus_1; 3606 if (extras == 0) { 3607 chunk_minus_1 = grainsize - 1; 3608 } else { 3609 chunk_minus_1 = grainsize; 3610 --extras; // first extras iterations get bigger chunk (grainsize+1) 3611 } 3612 upper = lower + st * chunk_minus_1; 3613 if (i == num_tasks - 1) { 3614 // schedule the last task, set lastprivate flag if needed 3615 if (st == 1) { // most common case 3616 KMP_DEBUG_ASSERT(upper == *ub); 3617 if (upper == ub_glob) 3618 lastpriv = 1; 3619 } else if (st > 0) { // positive loop stride 3620 KMP_DEBUG_ASSERT((kmp_uint64)st > *ub - upper); 3621 if ((kmp_uint64)st > ub_glob - upper) 3622 lastpriv = 1; 3623 } else { // negative loop stride 3624 KMP_DEBUG_ASSERT(upper + st < *ub); 3625 if (upper - ub_glob < (kmp_uint64)(-st)) 3626 lastpriv = 1; 3627 } 3628 } 3629 next_task = __kmp_task_dup_alloc(thread, task); // allocate new task 3630 // adjust task-specific bounds 3631 *(kmp_uint64 *)((char *)next_task + lower_offset) = lower; 3632 *(kmp_uint64 *)((char *)next_task + upper_offset) = upper; 3633 if (ptask_dup != NULL) // set lastprivate flag, construct fistprivates, etc. 3634 ptask_dup(next_task, task, lastpriv); 3635 KA_TRACE(40, ("__kmp_taskloop_linear: T#%d; task %p: lower %lld, " 3636 "upper %lld (offsets %p %p)\n", 3637 gtid, next_task, lower, upper, lower_offset, upper_offset)); 3638 __kmp_omp_task(gtid, next_task, true); // schedule new task 3639 lower = upper + st; // adjust lower bound for the next iteration 3640 } 3641 // free the pattern task and exit 3642 __kmp_task_start(gtid, task, current_task); // make internal bookkeeping 3643 // do not execute the pattern task, just do internal bookkeeping 3644 __kmp_task_finish(gtid, task, current_task); 3645 } 3646 3647 // Structure to keep taskloop parameters for auxiliary task 3648 // kept in the shareds of the task structure. 3649 typedef struct __taskloop_params { 3650 kmp_task_t *task; 3651 kmp_uint64 *lb; 3652 kmp_uint64 *ub; 3653 void *task_dup; 3654 kmp_int64 st; 3655 kmp_uint64 ub_glob; 3656 kmp_uint64 num_tasks; 3657 kmp_uint64 grainsize; 3658 kmp_uint64 extras; 3659 kmp_uint64 tc; 3660 kmp_uint64 num_t_min; 3661 } __taskloop_params_t; 3662 3663 void __kmp_taskloop_recur(ident_t *, int, kmp_task_t *, kmp_uint64 *, 3664 kmp_uint64 *, kmp_int64, kmp_uint64, kmp_uint64, 3665 kmp_uint64, kmp_uint64, kmp_uint64, kmp_uint64, 3666 void *); 3667 3668 // Execute part of the the taskloop submitted as a task. 3669 int __kmp_taskloop_task(int gtid, void *ptask) { 3670 __taskloop_params_t *p = 3671 (__taskloop_params_t *)((kmp_task_t *)ptask)->shareds; 3672 kmp_task_t *task = p->task; 3673 kmp_uint64 *lb = p->lb; 3674 kmp_uint64 *ub = p->ub; 3675 void *task_dup = p->task_dup; 3676 // p_task_dup_t ptask_dup = (p_task_dup_t)task_dup; 3677 kmp_int64 st = p->st; 3678 kmp_uint64 ub_glob = p->ub_glob; 3679 kmp_uint64 num_tasks = p->num_tasks; 3680 kmp_uint64 grainsize = p->grainsize; 3681 kmp_uint64 extras = p->extras; 3682 kmp_uint64 tc = p->tc; 3683 kmp_uint64 num_t_min = p->num_t_min; 3684 #if KMP_DEBUG 3685 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3686 KMP_DEBUG_ASSERT(task != NULL); 3687 KA_TRACE(20, ("__kmp_taskloop_task: T#%d, task %p: %lld tasks, grainsize" 3688 " %lld, extras %lld, i=%lld,%lld(%d), dup %p\n", 3689 gtid, taskdata, num_tasks, grainsize, extras, *lb, *ub, st, 3690 task_dup)); 3691 #endif 3692 KMP_DEBUG_ASSERT(num_tasks * 2 + 1 > num_t_min); 3693 if (num_tasks > num_t_min) 3694 __kmp_taskloop_recur(NULL, gtid, task, lb, ub, st, ub_glob, num_tasks, 3695 grainsize, extras, tc, num_t_min, task_dup); 3696 else 3697 __kmp_taskloop_linear(NULL, gtid, task, lb, ub, st, ub_glob, num_tasks, 3698 grainsize, extras, tc, task_dup); 3699 3700 KA_TRACE(40, ("__kmp_taskloop_task(exit): T#%d\n", gtid)); 3701 return 0; 3702 } 3703 3704 // Schedule part of the the taskloop as a task, 3705 // execute the rest of the the taskloop. 3706 // 3707 // loc Source location information 3708 // gtid Global thread ID 3709 // task Pattern task, exposes the loop iteration range 3710 // lb Pointer to loop lower bound in task structure 3711 // ub Pointer to loop upper bound in task structure 3712 // st Loop stride 3713 // ub_glob Global upper bound (used for lastprivate check) 3714 // num_tasks Number of tasks to execute 3715 // grainsize Number of loop iterations per task 3716 // extras Number of chunks with grainsize+1 iterations 3717 // tc Iterations count 3718 // num_t_min Threashold to launch tasks recursively 3719 // task_dup Tasks duplication routine 3720 void __kmp_taskloop_recur(ident_t *loc, int gtid, kmp_task_t *task, 3721 kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, 3722 kmp_uint64 ub_glob, kmp_uint64 num_tasks, 3723 kmp_uint64 grainsize, kmp_uint64 extras, 3724 kmp_uint64 tc, kmp_uint64 num_t_min, void *task_dup) { 3725 #if KMP_DEBUG 3726 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3727 KMP_DEBUG_ASSERT(task != NULL); 3728 KMP_DEBUG_ASSERT(num_tasks > num_t_min); 3729 KA_TRACE(20, ("__kmp_taskloop_recur: T#%d, task %p: %lld tasks, grainsize" 3730 " %lld, extras %lld, i=%lld,%lld(%d), dup %p\n", 3731 gtid, taskdata, num_tasks, grainsize, extras, *lb, *ub, st, 3732 task_dup)); 3733 #endif 3734 p_task_dup_t ptask_dup = (p_task_dup_t)task_dup; 3735 kmp_uint64 lower = *lb; 3736 kmp_uint64 upper = *ub; 3737 kmp_info_t *thread = __kmp_threads[gtid]; 3738 // kmp_taskdata_t *current_task = thread->th.th_current_task; 3739 kmp_task_t *next_task; 3740 kmp_int32 lastpriv = 0; 3741 size_t lower_offset = 3742 (char *)lb - (char *)task; // remember offset of lb in the task structure 3743 size_t upper_offset = 3744 (char *)ub - (char *)task; // remember offset of ub in the task structure 3745 3746 KMP_DEBUG_ASSERT(tc == num_tasks * grainsize + extras); 3747 KMP_DEBUG_ASSERT(num_tasks > extras); 3748 KMP_DEBUG_ASSERT(num_tasks > 0); 3749 3750 // split the loop in two halves 3751 kmp_uint64 lb1, ub0, tc0, tc1, ext0, ext1; 3752 kmp_uint64 gr_size0 = grainsize; 3753 kmp_uint64 n_tsk0 = num_tasks >> 1; // num_tasks/2 to execute 3754 kmp_uint64 n_tsk1 = num_tasks - n_tsk0; // to schedule as a task 3755 if (n_tsk0 <= extras) { 3756 gr_size0++; // integrate extras into grainsize 3757 ext0 = 0; // no extra iters in 1st half 3758 ext1 = extras - n_tsk0; // remaining extras 3759 tc0 = gr_size0 * n_tsk0; 3760 tc1 = tc - tc0; 3761 } else { // n_tsk0 > extras 3762 ext1 = 0; // no extra iters in 2nd half 3763 ext0 = extras; 3764 tc1 = grainsize * n_tsk1; 3765 tc0 = tc - tc1; 3766 } 3767 ub0 = lower + st * (tc0 - 1); 3768 lb1 = ub0 + st; 3769 3770 // create pattern task for 2nd half of the loop 3771 next_task = __kmp_task_dup_alloc(thread, task); // duplicate the task 3772 // adjust lower bound (upper bound is not changed) for the 2nd half 3773 *(kmp_uint64 *)((char *)next_task + lower_offset) = lb1; 3774 if (ptask_dup != NULL) // construct fistprivates, etc. 3775 ptask_dup(next_task, task, 0); 3776 *ub = ub0; // adjust upper bound for the 1st half 3777 3778 // create auxiliary task for 2nd half of the loop 3779 kmp_task_t *new_task = 3780 __kmpc_omp_task_alloc(loc, gtid, 1, 3 * sizeof(void *), 3781 sizeof(__taskloop_params_t), &__kmp_taskloop_task); 3782 __taskloop_params_t *p = (__taskloop_params_t *)new_task->shareds; 3783 p->task = next_task; 3784 p->lb = (kmp_uint64 *)((char *)next_task + lower_offset); 3785 p->ub = (kmp_uint64 *)((char *)next_task + upper_offset); 3786 p->task_dup = task_dup; 3787 p->st = st; 3788 p->ub_glob = ub_glob; 3789 p->num_tasks = n_tsk1; 3790 p->grainsize = grainsize; 3791 p->extras = ext1; 3792 p->tc = tc1; 3793 p->num_t_min = num_t_min; 3794 __kmp_omp_task(gtid, new_task, true); // schedule new task 3795 3796 // execute the 1st half of current subrange 3797 if (n_tsk0 > num_t_min) 3798 __kmp_taskloop_recur(loc, gtid, task, lb, ub, st, ub_glob, n_tsk0, gr_size0, 3799 ext0, tc0, num_t_min, task_dup); 3800 else 3801 __kmp_taskloop_linear(loc, gtid, task, lb, ub, st, ub_glob, n_tsk0, 3802 gr_size0, ext0, tc0, task_dup); 3803 3804 KA_TRACE(40, ("__kmpc_taskloop_recur(exit): T#%d\n", gtid)); 3805 } 3806 3807 /*! 3808 @ingroup TASKING 3809 @param loc Source location information 3810 @param gtid Global thread ID 3811 @param task Task structure 3812 @param if_val Value of the if clause 3813 @param lb Pointer to loop lower bound in task structure 3814 @param ub Pointer to loop upper bound in task structure 3815 @param st Loop stride 3816 @param nogroup Flag, 1 if nogroup clause specified, 0 otherwise 3817 @param sched Schedule specified 0/1/2 for none/grainsize/num_tasks 3818 @param grainsize Schedule value if specified 3819 @param task_dup Tasks duplication routine 3820 3821 Execute the taskloop construct. 3822 */ 3823 void __kmpc_taskloop(ident_t *loc, int gtid, kmp_task_t *task, int if_val, 3824 kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, int nogroup, 3825 int sched, kmp_uint64 grainsize, void *task_dup) { 3826 kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task); 3827 KMP_DEBUG_ASSERT(task != NULL); 3828 3829 KA_TRACE(20, ("__kmpc_taskloop: T#%d, task %p, lb %lld, ub %lld, st %lld, " 3830 "grain %llu(%d), dup %p\n", 3831 gtid, taskdata, *lb, *ub, st, grainsize, sched, task_dup)); 3832 3833 #if OMPT_SUPPORT && OMPT_OPTIONAL 3834 ompt_team_info_t *team_info = __ompt_get_teaminfo(0, NULL); 3835 ompt_task_info_t *task_info = __ompt_get_task_info_object(0); 3836 if (ompt_enabled.ompt_callback_work) { 3837 ompt_callbacks.ompt_callback(ompt_callback_work)( 3838 ompt_work_taskloop, ompt_scope_begin, &(team_info->parallel_data), 3839 &(task_info->task_data), 0, OMPT_GET_RETURN_ADDRESS(0)); 3840 } 3841 #endif 3842 3843 if (nogroup == 0) { 3844 #if OMPT_SUPPORT && OMPT_OPTIONAL 3845 OMPT_STORE_RETURN_ADDRESS(gtid); 3846 #endif 3847 __kmpc_taskgroup(loc, gtid); 3848 } 3849 3850 // ========================================================================= 3851 // calculate loop parameters 3852 kmp_uint64 tc; 3853 kmp_uint64 lower = *lb; // compiler provides global bounds here 3854 kmp_uint64 upper = *ub; 3855 kmp_uint64 ub_glob = upper; // global upper used to calc lastprivate flag 3856 kmp_uint64 num_tasks = 0, extras = 0; 3857 kmp_uint64 num_tasks_min = __kmp_taskloop_min_tasks; 3858 kmp_info_t *thread = __kmp_threads[gtid]; 3859 kmp_taskdata_t *current_task = thread->th.th_current_task; 3860 3861 // compute trip count 3862 if (st == 1) { // most common case 3863 tc = upper - lower + 1; 3864 } else if (st < 0) { 3865 tc = (lower - upper) / (-st) + 1; 3866 } else { // st > 0 3867 tc = (upper - lower) / st + 1; 3868 } 3869 if (tc == 0) { 3870 KA_TRACE(20, ("__kmpc_taskloop(exit): T#%d zero-trip loop\n", gtid)); 3871 // free the pattern task and exit 3872 __kmp_task_start(gtid, task, current_task); 3873 // do not execute anything for zero-trip loop 3874 __kmp_task_finish(gtid, task, current_task); 3875 return; 3876 } 3877 if (num_tasks_min == 0) 3878 // TODO: can we choose better default heuristic? 3879 num_tasks_min = 3880 KMP_MIN(thread->th.th_team_nproc * 10, INITIAL_TASK_DEQUE_SIZE); 3881 3882 // compute num_tasks/grainsize based on the input provided 3883 switch (sched) { 3884 case 0: // no schedule clause specified, we can choose the default 3885 // let's try to schedule (team_size*10) tasks 3886 grainsize = thread->th.th_team_nproc * 10; 3887 case 2: // num_tasks provided 3888 if (grainsize > tc) { 3889 num_tasks = tc; // too big num_tasks requested, adjust values 3890 grainsize = 1; 3891 extras = 0; 3892 } else { 3893 num_tasks = grainsize; 3894 grainsize = tc / num_tasks; 3895 extras = tc % num_tasks; 3896 } 3897 break; 3898 case 1: // grainsize provided 3899 if (grainsize > tc) { 3900 num_tasks = 1; // too big grainsize requested, adjust values 3901 grainsize = tc; 3902 extras = 0; 3903 } else { 3904 num_tasks = tc / grainsize; 3905 // adjust grainsize for balanced distribution of iterations 3906 grainsize = tc / num_tasks; 3907 extras = tc % num_tasks; 3908 } 3909 break; 3910 default: 3911 KMP_ASSERT2(0, "unknown scheduling of taskloop"); 3912 } 3913 KMP_DEBUG_ASSERT(tc == num_tasks * grainsize + extras); 3914 KMP_DEBUG_ASSERT(num_tasks > extras); 3915 KMP_DEBUG_ASSERT(num_tasks > 0); 3916 // ========================================================================= 3917 3918 // check if clause value first 3919 if (if_val == 0) { // if(0) specified, mark task as serial 3920 taskdata->td_flags.task_serial = 1; 3921 taskdata->td_flags.tiedness = TASK_TIED; // AC: serial task cannot be untied 3922 #if OMPT_SUPPORT && OMPT_OPTIONAL 3923 OMPT_STORE_RETURN_ADDRESS(gtid); 3924 #endif 3925 // always start serial tasks linearly 3926 __kmp_taskloop_linear(loc, gtid, task, lb, ub, st, ub_glob, num_tasks, 3927 grainsize, extras, tc, task_dup); 3928 } else if (num_tasks > num_tasks_min) { 3929 KA_TRACE(20, ("__kmpc_taskloop: T#%d, go recursive: tc %llu, #tasks %llu" 3930 "(%lld), grain %llu, extras %llu\n", 3931 gtid, tc, num_tasks, num_tasks_min, grainsize, extras)); 3932 #if OMPT_SUPPORT && OMPT_OPTIONAL 3933 OMPT_STORE_RETURN_ADDRESS(gtid); 3934 #endif 3935 __kmp_taskloop_recur(loc, gtid, task, lb, ub, st, ub_glob, num_tasks, 3936 grainsize, extras, tc, num_tasks_min, task_dup); 3937 } else { 3938 KA_TRACE(20, ("__kmpc_taskloop: T#%d, go linear: tc %llu, #tasks %llu" 3939 "(%lld), grain %llu, extras %llu\n", 3940 gtid, tc, num_tasks, num_tasks_min, grainsize, extras)); 3941 #if OMPT_SUPPORT && OMPT_OPTIONAL 3942 OMPT_STORE_RETURN_ADDRESS(gtid); 3943 #endif 3944 __kmp_taskloop_linear(loc, gtid, task, lb, ub, st, ub_glob, num_tasks, 3945 grainsize, extras, tc, task_dup); 3946 } 3947 3948 if (nogroup == 0) { 3949 #if OMPT_SUPPORT && OMPT_OPTIONAL 3950 OMPT_STORE_RETURN_ADDRESS(gtid); 3951 #endif 3952 __kmpc_end_taskgroup(loc, gtid); 3953 } 3954 #if OMPT_SUPPORT && OMPT_OPTIONAL 3955 if (ompt_enabled.ompt_callback_work) { 3956 ompt_callbacks.ompt_callback(ompt_callback_work)( 3957 ompt_work_taskloop, ompt_scope_end, &(team_info->parallel_data), 3958 &(task_info->task_data), 0, OMPT_GET_RETURN_ADDRESS(0)); 3959 } 3960 #endif 3961 KA_TRACE(20, ("__kmpc_taskloop(exit): T#%d\n", gtid)); 3962 } 3963 3964 #endif 3965