1 /* 2 * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "jfr/jfrEvents.hpp" 27 #include "jfr/jni/jfrJavaSupport.hpp" 28 #include "jfr/recorder/jfrRecorder.hpp" 29 #include "jfr/recorder/repository/jfrChunkWriter.hpp" 30 #include "jfr/recorder/service/jfrOptionSet.hpp" 31 #include "jfr/recorder/service/jfrPostBox.hpp" 32 #include "jfr/recorder/storage/jfrMemorySpace.inline.hpp" 33 #include "jfr/recorder/storage/jfrStorage.hpp" 34 #include "jfr/recorder/storage/jfrStorageControl.hpp" 35 #include "jfr/recorder/storage/jfrStorageUtils.inline.hpp" 36 #include "jfr/utilities/jfrIterator.hpp" 37 #include "jfr/utilities/jfrTime.hpp" 38 #include "jfr/writers/jfrNativeEventWriter.hpp" 39 #include "logging/log.hpp" 40 #include "runtime/mutexLocker.hpp" 41 #include "runtime/orderAccess.hpp" 42 #include "runtime/os.inline.hpp" 43 #include "runtime/safepoint.hpp" 44 #include "runtime/thread.hpp" 45 46 typedef JfrStorage::Buffer* BufferPtr; 47 48 static JfrStorage* _instance = NULL; 49 static JfrStorageControl* _control; 50 51 JfrStorage& JfrStorage::instance() { 52 return *_instance; 53 } 54 55 JfrStorage* JfrStorage::create(JfrChunkWriter& chunkwriter, JfrPostBox& post_box) { 56 assert(_instance == NULL, "invariant"); 57 _instance = new JfrStorage(chunkwriter, post_box); 58 return _instance; 59 } 60 61 void JfrStorage::destroy() { 62 if (_instance != NULL) { 63 delete _instance; 64 _instance = NULL; 65 } 66 } 67 68 JfrStorage::JfrStorage(JfrChunkWriter& chunkwriter, JfrPostBox& post_box) : 69 _control(NULL), 70 _global_mspace(NULL), 71 _thread_local_mspace(NULL), 72 _transient_mspace(NULL), 73 _age_mspace(NULL), 74 _chunkwriter(chunkwriter), 75 _post_box(post_box) {} 76 77 JfrStorage::~JfrStorage() { 78 if (_control != NULL) { 79 delete _control; 80 } 81 if (_global_mspace != NULL) { 82 delete _global_mspace; 83 } 84 if (_thread_local_mspace != NULL) { 85 delete _thread_local_mspace; 86 } 87 if (_transient_mspace != NULL) { 88 delete _transient_mspace; 89 } 90 if (_age_mspace != NULL) { 91 delete _age_mspace; 92 } 93 _instance = NULL; 94 } 95 96 static const size_t in_memory_discard_threshold_delta = 2; // start to discard data when the only this number of free buffers are left 97 static const size_t unlimited_mspace_size = 0; 98 static const size_t thread_local_cache_count = 8; 99 static const size_t thread_local_scavenge_threshold = thread_local_cache_count / 2; 100 static const size_t transient_buffer_size_multiplier = 8; // against thread local buffer size 101 102 template <typename Mspace> 103 static Mspace* create_mspace(size_t buffer_size, size_t limit, size_t cache_count, JfrStorage* storage_instance) { 104 Mspace* mspace = new Mspace(buffer_size, limit, cache_count, storage_instance); 105 if (mspace != NULL) { 106 mspace->initialize(); 107 } 108 return mspace; 109 } 110 111 bool JfrStorage::initialize() { 112 assert(_control == NULL, "invariant"); 113 assert(_global_mspace == NULL, "invariant"); 114 assert(_thread_local_mspace == NULL, "invariant"); 115 assert(_transient_mspace == NULL, "invariant"); 116 assert(_age_mspace == NULL, "invariant"); 117 118 const size_t num_global_buffers = (size_t)JfrOptionSet::num_global_buffers(); 119 assert(num_global_buffers >= in_memory_discard_threshold_delta, "invariant"); 120 const size_t memory_size = (size_t)JfrOptionSet::memory_size(); 121 const size_t global_buffer_size = (size_t)JfrOptionSet::global_buffer_size(); 122 const size_t thread_buffer_size = (size_t)JfrOptionSet::thread_buffer_size(); 123 124 _control = new JfrStorageControl(num_global_buffers, num_global_buffers - in_memory_discard_threshold_delta); 125 if (_control == NULL) { 126 return false; 127 } 128 _global_mspace = create_mspace<JfrStorageMspace>(global_buffer_size, memory_size, num_global_buffers, this); 129 if (_global_mspace == NULL) { 130 return false; 131 } 132 _thread_local_mspace = create_mspace<JfrThreadLocalMspace>(thread_buffer_size, unlimited_mspace_size, thread_local_cache_count, this); 133 if (_thread_local_mspace == NULL) { 134 return false; 135 } 136 _transient_mspace = create_mspace<JfrStorageMspace>(thread_buffer_size * transient_buffer_size_multiplier, unlimited_mspace_size, 0, this); 137 if (_transient_mspace == NULL) { 138 return false; 139 } 140 _age_mspace = create_mspace<JfrStorageAgeMspace>(0 /* no extra size except header */, unlimited_mspace_size, num_global_buffers, this); 141 if (_age_mspace == NULL) { 142 return false; 143 } 144 control().set_scavenge_threshold(thread_local_scavenge_threshold); 145 return true; 146 } 147 148 JfrStorageControl& JfrStorage::control() { 149 return *instance()._control; 150 } 151 152 static void log_allocation_failure(const char* msg, size_t size) { 153 log_warning(jfr)("Unable to allocate " SIZE_FORMAT " bytes of %s.", size, msg); 154 } 155 156 BufferPtr JfrStorage::acquire_thread_local(Thread* thread, size_t size /* 0 */) { 157 BufferPtr buffer = mspace_get_to_full(size, instance()._thread_local_mspace, thread); 158 if (buffer == NULL) { 159 log_allocation_failure("thread local_memory", size); 160 return NULL; 161 } 162 assert(buffer->acquired_by_self(), "invariant"); 163 return buffer; 164 } 165 166 BufferPtr JfrStorage::acquire_transient(size_t size, Thread* thread) { 167 BufferPtr buffer = mspace_allocate_transient_lease_to_full(size, instance()._transient_mspace, thread); 168 if (buffer == NULL) { 169 log_allocation_failure("transient memory", size); 170 return NULL; 171 } 172 assert(buffer->acquired_by_self(), "invariant"); 173 assert(buffer->transient(), "invariant"); 174 assert(buffer->lease(), "invariant"); 175 return buffer; 176 } 177 178 static BufferPtr get_lease(size_t size, JfrStorageMspace* mspace, JfrStorage& storage_instance, size_t retry_count, Thread* thread) { 179 assert(size <= mspace->min_elem_size(), "invariant"); 180 while (true) { 181 BufferPtr t = mspace_get_free_lease_with_retry(size, mspace, retry_count, thread); 182 if (t == NULL && storage_instance.control().should_discard()) { 183 storage_instance.discard_oldest(thread); 184 continue; 185 } 186 return t; 187 } 188 } 189 190 static BufferPtr get_promotion_buffer(size_t size, JfrStorageMspace* mspace, JfrStorage& storage_instance, size_t retry_count, Thread* thread) { 191 assert(size <= mspace->min_elem_size(), "invariant"); 192 while (true) { 193 BufferPtr t = mspace_get_free_with_retry(size, mspace, retry_count, thread); 194 if (t == NULL && storage_instance.control().should_discard()) { 195 storage_instance.discard_oldest(thread); 196 continue; 197 } 198 return t; 199 } 200 } 201 202 static const size_t lease_retry = 10; 203 204 BufferPtr JfrStorage::acquire_large(size_t size, Thread* thread) { 205 JfrStorage& storage_instance = instance(); 206 const size_t max_elem_size = storage_instance._global_mspace->min_elem_size(); // min is also max 207 // if not too large and capacity is still available, ask for a lease from the global system 208 if (size < max_elem_size && storage_instance.control().is_global_lease_allowed()) { 209 BufferPtr const buffer = get_lease(size, storage_instance._global_mspace, storage_instance, lease_retry, thread); 210 if (buffer != NULL) { 211 assert(buffer->acquired_by_self(), "invariant"); 212 assert(!buffer->transient(), "invariant"); 213 assert(buffer->lease(), "invariant"); 214 storage_instance.control().increment_leased(); 215 return buffer; 216 } 217 } 218 return acquire_transient(size, thread); 219 } 220 221 static void write_data_loss_event(JfrBuffer* buffer, u8 unflushed_size, Thread* thread) { 222 assert(buffer != NULL, "invariant"); 223 assert(buffer->empty(), "invariant"); 224 const u8 total_data_loss = thread->jfr_thread_local()->add_data_lost(unflushed_size); 225 if (EventDataLoss::is_enabled()) { 226 JfrNativeEventWriter writer(buffer, thread); 227 writer.write<u8>(EventDataLoss::eventId); 228 writer.write(JfrTicks::now()); 229 writer.write(unflushed_size); 230 writer.write(total_data_loss); 231 } 232 } 233 234 static void write_data_loss(BufferPtr buffer, Thread* thread) { 235 assert(buffer != NULL, "invariant"); 236 const size_t unflushed_size = buffer->unflushed_size(); 237 buffer->concurrent_reinitialization(); 238 if (unflushed_size == 0) { 239 return; 240 } 241 write_data_loss_event(buffer, unflushed_size, thread); 242 } 243 244 static const size_t promotion_retry = 100; 245 246 bool JfrStorage::flush_regular_buffer(BufferPtr buffer, Thread* thread) { 247 assert(buffer != NULL, "invariant"); 248 assert(!buffer->lease(), "invariant"); 249 assert(!buffer->transient(), "invariant"); 250 const size_t unflushed_size = buffer->unflushed_size(); 251 if (unflushed_size == 0) { 252 buffer->concurrent_reinitialization(); 253 assert(buffer->empty(), "invariant"); 254 return true; 255 } 256 BufferPtr const promotion_buffer = get_promotion_buffer(unflushed_size, _global_mspace, *this, promotion_retry, thread); 257 if (promotion_buffer == NULL) { 258 write_data_loss(buffer, thread); 259 return false; 260 } 261 assert(promotion_buffer->acquired_by_self(), "invariant"); 262 assert(promotion_buffer->free_size() >= unflushed_size, "invariant"); 263 buffer->concurrent_move_and_reinitialize(promotion_buffer, unflushed_size); 264 assert(buffer->empty(), "invariant"); 265 return true; 266 } 267 268 /* 269 * 1. If the buffer was a "lease" from the global system, release back. 270 * 2. If the buffer is transient (temporal dynamically allocated), retire and register full. 271 * 272 * The buffer is effectively invalidated for the thread post-return, 273 * and the caller should take means to ensure that it is not referenced any longer. 274 */ 275 void JfrStorage::release_large(BufferPtr buffer, Thread* thread) { 276 assert(buffer != NULL, "invariant"); 277 assert(buffer->lease(), "invariant"); 278 assert(buffer->acquired_by_self(), "invariant"); 279 buffer->clear_lease(); 280 if (buffer->transient()) { 281 buffer->set_retired(); 282 register_full(buffer, thread); 283 } else { 284 buffer->release(); 285 control().decrement_leased(); 286 } 287 } 288 289 static JfrAgeNode* new_age_node(BufferPtr buffer, JfrStorageAgeMspace* age_mspace, Thread* thread) { 290 assert(buffer != NULL, "invariant"); 291 assert(age_mspace != NULL, "invariant"); 292 return mspace_allocate_transient(0, age_mspace, thread); 293 } 294 295 static void log_registration_failure(size_t unflushed_size) { 296 log_warning(jfr)("Unable to register a full buffer of " SIZE_FORMAT " bytes.", unflushed_size); 297 log_debug(jfr, system)("Cleared 1 full buffer of " SIZE_FORMAT " bytes.", unflushed_size); 298 } 299 300 static void handle_registration_failure(BufferPtr buffer) { 301 assert(buffer != NULL, "invariant"); 302 assert(buffer->retired(), "invariant"); 303 const size_t unflushed_size = buffer->unflushed_size(); 304 buffer->reinitialize(); 305 log_registration_failure(unflushed_size); 306 } 307 308 static JfrAgeNode* get_free_age_node(JfrStorageAgeMspace* age_mspace, Thread* thread) { 309 assert(JfrBuffer_lock->owned_by_self(), "invariant"); 310 return mspace_get_free_with_detach(0, age_mspace, thread); 311 } 312 313 static bool insert_full_age_node(JfrAgeNode* age_node, JfrStorageAgeMspace* age_mspace, Thread* thread) { 314 assert(JfrBuffer_lock->owned_by_self(), "invariant"); 315 assert(age_node->retired_buffer()->retired(), "invariant"); 316 age_mspace->insert_full_head(age_node); 317 return true; 318 } 319 320 static bool full_buffer_registration(BufferPtr buffer, JfrStorageAgeMspace* age_mspace, JfrStorageControl& control, Thread* thread) { 321 assert(buffer != NULL, "invariant"); 322 assert(buffer->retired(), "invariant"); 323 assert(age_mspace != NULL, "invariant"); 324 MutexLockerEx lock(JfrBuffer_lock, Mutex::_no_safepoint_check_flag); 325 JfrAgeNode* age_node = get_free_age_node(age_mspace, thread); 326 if (age_node == NULL) { 327 age_node = new_age_node(buffer, age_mspace, thread); 328 if (age_node == NULL) { 329 return false; 330 } 331 } 332 assert(age_node->acquired_by_self(), "invariant"); 333 assert(age_node != NULL, "invariant"); 334 age_node->set_retired_buffer(buffer); 335 control.increment_full(); 336 return insert_full_age_node(age_node, age_mspace, thread); 337 } 338 339 void JfrStorage::register_full(BufferPtr buffer, Thread* thread) { 340 assert(buffer != NULL, "invariant"); 341 assert(buffer->retired(), "invariant"); 342 if (!full_buffer_registration(buffer, _age_mspace, control(), thread)) { 343 handle_registration_failure(buffer); 344 buffer->release(); 345 } 346 if (control().should_post_buffer_full_message()) { 347 _post_box.post(MSG_FULLBUFFER); 348 } 349 } 350 351 void JfrStorage::lock() { 352 assert(!JfrBuffer_lock->owned_by_self(), "invariant"); 353 JfrBuffer_lock->lock_without_safepoint_check(); 354 } 355 356 void JfrStorage::unlock() { 357 assert(JfrBuffer_lock->owned_by_self(), "invariant"); 358 JfrBuffer_lock->unlock(); 359 } 360 361 #ifdef ASSERT 362 bool JfrStorage::is_locked() const { 363 return JfrBuffer_lock->owned_by_self(); 364 } 365 #endif 366 367 // don't use buffer on return, it is gone 368 void JfrStorage::release(BufferPtr buffer, Thread* thread) { 369 assert(buffer != NULL, "invariant"); 370 assert(!buffer->lease(), "invariant"); 371 assert(!buffer->transient(), "invariant"); 372 assert(!buffer->retired(), "invariant"); 373 if (!buffer->empty()) { 374 if (!flush_regular_buffer(buffer, thread)) { 375 buffer->concurrent_reinitialization(); 376 } 377 } 378 assert(buffer->empty(), "invariant"); 379 control().increment_dead(); 380 buffer->release(); 381 buffer->set_retired(); 382 } 383 384 void JfrStorage::release_thread_local(BufferPtr buffer, Thread* thread) { 385 assert(buffer != NULL, "invariant"); 386 JfrStorage& storage_instance = instance(); 387 storage_instance.release(buffer, thread); 388 if (storage_instance.control().should_scavenge()) { 389 storage_instance._post_box.post(MSG_DEADBUFFER); 390 } 391 } 392 393 static void log_discard(size_t count, size_t amount, size_t current) { 394 if (log_is_enabled(Debug, jfr, system)) { 395 assert(count > 0, "invariant"); 396 log_debug(jfr, system)("Cleared " SIZE_FORMAT " full buffer(s) of " SIZE_FORMAT" bytes.", count, amount); 397 log_debug(jfr, system)("Current number of full buffers " SIZE_FORMAT "", current); 398 } 399 } 400 401 void JfrStorage::discard_oldest(Thread* thread) { 402 if (JfrBuffer_lock->try_lock()) { 403 if (!control().should_discard()) { 404 // another thread handled it 405 return; 406 } 407 const size_t num_full_pre_discard = control().full_count(); 408 size_t num_full_post_discard = 0; 409 size_t discarded_size = 0; 410 while (true) { 411 JfrAgeNode* const oldest_age_node = _age_mspace->full_tail(); 412 if (oldest_age_node == NULL) { 413 break; 414 } 415 BufferPtr const buffer = oldest_age_node->retired_buffer(); 416 assert(buffer->retired(), "invariant"); 417 discarded_size += buffer->unflushed_size(); 418 num_full_post_discard = control().decrement_full(); 419 if (buffer->transient()) { 420 mspace_release_full(buffer, _transient_mspace); 421 mspace_release_full(oldest_age_node, _age_mspace); 422 continue; 423 } else { 424 mspace_release_full(oldest_age_node, _age_mspace); 425 buffer->reinitialize(); 426 buffer->release(); // pusb 427 break; 428 } 429 } 430 JfrBuffer_lock->unlock(); 431 const size_t number_of_discards = num_full_pre_discard - num_full_post_discard; 432 if (number_of_discards > 0) { 433 log_discard(number_of_discards, discarded_size, num_full_post_discard); 434 } 435 } 436 } 437 438 #ifdef ASSERT 439 typedef const BufferPtr ConstBufferPtr; 440 441 static void assert_flush_precondition(ConstBufferPtr cur, size_t used, bool native, const Thread* t) { 442 assert(t != NULL, "invariant"); 443 assert(cur != NULL, "invariant"); 444 assert(cur->pos() + used <= cur->end(), "invariant"); 445 assert(native ? t->jfr_thread_local()->native_buffer() == cur : t->jfr_thread_local()->java_buffer() == cur, "invariant"); 446 } 447 448 static void assert_flush_regular_precondition(ConstBufferPtr cur, const u1* const cur_pos, size_t used, size_t req, const Thread* t) { 449 assert(t != NULL, "invariant"); 450 assert(t->jfr_thread_local()->shelved_buffer() == NULL, "invariant"); 451 assert(cur != NULL, "invariant"); 452 assert(!cur->lease(), "invariant"); 453 assert(cur_pos != NULL, "invariant"); 454 assert(req >= used, "invariant"); 455 } 456 457 static void assert_provision_large_precondition(ConstBufferPtr cur, size_t used, size_t req, const Thread* t) { 458 assert(cur != NULL, "invariant"); 459 assert(t != NULL, "invariant"); 460 assert(t->jfr_thread_local()->shelved_buffer() != NULL, "invariant"); 461 assert(req >= used, "invariant"); 462 } 463 464 static void assert_flush_large_precondition(ConstBufferPtr cur, const u1* const cur_pos, size_t used, size_t req, bool native, Thread* t) { 465 assert(t != NULL, "invariant"); 466 assert(cur != NULL, "invariant"); 467 assert(cur->lease(), "invariant"); 468 assert(cur_pos != NULL, "invariant"); 469 assert(native ? t->jfr_thread_local()->native_buffer() == cur : t->jfr_thread_local()->java_buffer() == cur, "invariant"); 470 assert(t->jfr_thread_local()->shelved_buffer() != NULL, "invariant"); 471 assert(req >= used, "invariant"); 472 assert(cur != t->jfr_thread_local()->shelved_buffer(), "invariant"); 473 } 474 #endif // ASSERT 475 476 BufferPtr JfrStorage::flush(BufferPtr cur, size_t used, size_t req, bool native, Thread* t) { 477 debug_only(assert_flush_precondition(cur, used, native, t);) 478 const u1* const cur_pos = cur->pos(); 479 req += used; 480 // requested size now encompass the outstanding used size 481 return cur->lease() ? instance().flush_large(cur, cur_pos, used, req, native, t) : 482 instance().flush_regular(cur, cur_pos, used, req, native, t); 483 } 484 485 BufferPtr JfrStorage::flush_regular(BufferPtr cur, const u1* const cur_pos, size_t used, size_t req, bool native, Thread* t) { 486 debug_only(assert_flush_regular_precondition(cur, cur_pos, used, req, t);) 487 // A flush is needed before memcpy since a non-large buffer is thread stable 488 // (thread local). The flush will not modify memory in addresses above pos() 489 // which is where the "used / uncommitted" data resides. It is therefore both 490 // possible and valid to migrate data after the flush. This is however only 491 // the case for stable thread local buffers; it is not the case for large buffers. 492 if (!cur->empty()) { 493 flush_regular_buffer(cur, t); 494 } 495 assert(t->jfr_thread_local()->shelved_buffer() == NULL, "invariant"); 496 if (cur->free_size() >= req) { 497 // simplest case, no switching of buffers 498 if (used > 0) { 499 memcpy(cur->pos(), (void*)cur_pos, used); 500 } 501 assert(native ? t->jfr_thread_local()->native_buffer() == cur : t->jfr_thread_local()->java_buffer() == cur, "invariant"); 502 return cur; 503 } 504 // Going for a "larger-than-regular" buffer. 505 // Shelve the current buffer to make room for a temporary lease. 506 t->jfr_thread_local()->shelve_buffer(cur); 507 return provision_large(cur, cur_pos, used, req, native, t); 508 } 509 510 static BufferPtr store_buffer_to_thread_local(BufferPtr buffer, JfrThreadLocal* jfr_thread_local, bool native) { 511 assert(buffer != NULL, "invariant"); 512 if (native) { 513 jfr_thread_local->set_native_buffer(buffer); 514 } else { 515 jfr_thread_local->set_java_buffer(buffer); 516 } 517 return buffer; 518 } 519 520 static BufferPtr restore_shelved_buffer(bool native, Thread* t) { 521 JfrThreadLocal* const tl = t->jfr_thread_local(); 522 BufferPtr shelved = tl->shelved_buffer(); 523 assert(shelved != NULL, "invariant"); 524 tl->shelve_buffer(NULL); 525 // restore shelved buffer back as primary 526 return store_buffer_to_thread_local(shelved, tl, native); 527 } 528 529 BufferPtr JfrStorage::flush_large(BufferPtr cur, const u1* const cur_pos, size_t used, size_t req, bool native, Thread* t) { 530 debug_only(assert_flush_large_precondition(cur, cur_pos, used, req, native, t);) 531 // Can the "regular" buffer (now shelved) accommodate the requested size? 532 BufferPtr shelved = t->jfr_thread_local()->shelved_buffer(); 533 assert(shelved != NULL, "invariant"); 534 if (shelved->free_size() >= req) { 535 if (req > 0) { 536 memcpy(shelved->pos(), (void*)cur_pos, (size_t)used); 537 } 538 // release and invalidate 539 release_large(cur, t); 540 return restore_shelved_buffer(native, t); 541 } 542 // regular too small 543 return provision_large(cur, cur_pos, used, req, native, t); 544 } 545 546 static BufferPtr large_fail(BufferPtr cur, bool native, JfrStorage& storage_instance, Thread* t) { 547 assert(cur != NULL, "invariant"); 548 assert(t != NULL, "invariant"); 549 if (cur->lease()) { 550 storage_instance.release_large(cur, t); 551 } 552 return restore_shelved_buffer(native, t); 553 } 554 555 // Always returns a non-null buffer. 556 // If accommodating the large request fails, the shelved buffer is returned 557 // even though it might be smaller than the requested size. 558 // Caller needs to ensure if the size was successfully accommodated. 559 BufferPtr JfrStorage::provision_large(BufferPtr cur, const u1* const cur_pos, size_t used, size_t req, bool native, Thread* t) { 560 debug_only(assert_provision_large_precondition(cur, used, req, t);) 561 assert(t->jfr_thread_local()->shelved_buffer() != NULL, "invariant"); 562 BufferPtr const buffer = acquire_large(req, t); 563 if (buffer == NULL) { 564 // unable to allocate and serve the request 565 return large_fail(cur, native, *this, t); 566 } 567 // ok managed to acquire a "large" buffer for the requested size 568 assert(buffer->free_size() >= req, "invariant"); 569 assert(buffer->lease(), "invariant"); 570 // transfer outstanding data 571 memcpy(buffer->pos(), (void*)cur_pos, used); 572 if (cur->lease()) { 573 release_large(cur, t); 574 // don't use current anymore, it is gone 575 } 576 return store_buffer_to_thread_local(buffer, t->jfr_thread_local(), native); 577 } 578 579 typedef UnBufferedWriteToChunk<JfrBuffer> WriteOperation; 580 typedef MutexedWriteOp<WriteOperation> MutexedWriteOperation; 581 typedef ConcurrentWriteOp<WriteOperation> ConcurrentWriteOperation; 582 typedef ConcurrentWriteOpExcludeRetired<WriteOperation> ThreadLocalConcurrentWriteOperation; 583 584 size_t JfrStorage::write() { 585 const size_t full_size_processed = write_full(); 586 WriteOperation wo(_chunkwriter); 587 ThreadLocalConcurrentWriteOperation tlwo(wo); 588 process_full_list(tlwo, _thread_local_mspace); 589 ConcurrentWriteOperation cwo(wo); 590 process_free_list(cwo, _global_mspace); 591 return full_size_processed + wo.processed(); 592 } 593 594 size_t JfrStorage::write_at_safepoint() { 595 assert(SafepointSynchronize::is_at_safepoint(), "invariant"); 596 WriteOperation wo(_chunkwriter); 597 MutexedWriteOperation writer(wo); // mutexed write mode 598 process_full_list(writer, _thread_local_mspace); 599 assert(_transient_mspace->is_free_empty(), "invariant"); 600 process_full_list(writer, _transient_mspace); 601 assert(_global_mspace->is_full_empty(), "invariant"); 602 process_free_list(writer, _global_mspace); 603 return wo.processed(); 604 } 605 606 typedef DiscardOp<DefaultDiscarder<JfrStorage::Buffer> > DiscardOperation; 607 typedef ReleaseOp<JfrStorageMspace> ReleaseOperation; 608 typedef CompositeOperation<MutexedWriteOperation, ReleaseOperation> FullOperation; 609 610 size_t JfrStorage::clear() { 611 const size_t full_size_processed = clear_full(); 612 DiscardOperation discarder(concurrent); // concurrent discard mode 613 process_full_list(discarder, _thread_local_mspace); 614 assert(_transient_mspace->is_free_empty(), "invariant"); 615 process_full_list(discarder, _transient_mspace); 616 assert(_global_mspace->is_full_empty(), "invariant"); 617 process_free_list(discarder, _global_mspace); 618 return full_size_processed + discarder.processed(); 619 } 620 621 static void insert_free_age_nodes(JfrStorageAgeMspace* age_mspace, JfrAgeNode* head, JfrAgeNode* tail, size_t count) { 622 if (tail != NULL) { 623 assert(tail->next() == NULL, "invariant"); 624 assert(head != NULL, "invariant"); 625 assert(head->prev() == NULL, "invariant"); 626 MutexLockerEx buffer_lock(JfrBuffer_lock, Mutex::_no_safepoint_check_flag); 627 age_mspace->insert_free_tail(head, tail, count); 628 } 629 } 630 631 template <typename Processor> 632 static void process_age_list(Processor& processor, JfrStorageAgeMspace* age_mspace, JfrAgeNode* head, size_t count) { 633 assert(age_mspace != NULL, "invariant"); 634 assert(head != NULL, "invariant"); 635 assert(count > 0, "invariant"); 636 JfrAgeNode* node = head; 637 JfrAgeNode* last = NULL; 638 while (node != NULL) { 639 last = node; 640 BufferPtr const buffer = node->retired_buffer(); 641 assert(buffer != NULL, "invariant"); 642 assert(buffer->retired(), "invariant"); 643 processor.process(buffer); 644 // at this point, buffer is already live or destroyed 645 node->clear_identity(); 646 JfrAgeNode* const next = (JfrAgeNode*)node->next(); 647 if (node->transient()) { 648 // detach 649 last = (JfrAgeNode*)last->prev(); 650 if (last != NULL) { 651 last->set_next(next); 652 } else { 653 head = next; 654 } 655 if (next != NULL) { 656 next->set_prev(last); 657 } 658 --count; 659 age_mspace->deallocate(node); 660 } 661 node = next; 662 } 663 insert_free_age_nodes(age_mspace, head, last, count); 664 } 665 666 template <typename Processor> 667 static size_t process_full(Processor& processor, JfrStorageControl& control, JfrStorageAgeMspace* age_mspace) { 668 assert(age_mspace != NULL, "invariant"); 669 if (age_mspace->is_full_empty()) { 670 // nothing to do 671 return 0; 672 } 673 size_t count; 674 JfrAgeNode* head; 675 { 676 // fetch age list 677 MutexLockerEx buffer_lock(JfrBuffer_lock, Mutex::_no_safepoint_check_flag); 678 count = age_mspace->full_count(); 679 head = age_mspace->clear_full(); 680 control.reset_full(); 681 } 682 assert(head != NULL, "invariant"); 683 assert(count > 0, "invariant"); 684 process_age_list(processor, age_mspace, head, count); 685 return count; 686 } 687 688 static void log(size_t count, size_t amount, bool clear = false) { 689 if (log_is_enabled(Debug, jfr, system)) { 690 if (count > 0) { 691 log_debug(jfr, system)("%s " SIZE_FORMAT " full buffer(s) of " SIZE_FORMAT" B of data%s", 692 clear ? "Discarded" : "Wrote", count, amount, clear ? "." : " to chunk."); 693 } 694 } 695 } 696 697 // full writer 698 // Assumption is retired only; exclusive access 699 // MutexedWriter -> ReleaseOp 700 // 701 size_t JfrStorage::write_full() { 702 assert(_chunkwriter.is_valid(), "invariant"); 703 Thread* const thread = Thread::current(); 704 WriteOperation wo(_chunkwriter); 705 MutexedWriteOperation writer(wo); // a retired buffer implies mutexed access 706 ReleaseOperation ro(_transient_mspace, thread); 707 FullOperation cmd(&writer, &ro); 708 const size_t count = process_full(cmd, control(), _age_mspace); 709 log(count, writer.processed()); 710 return writer.processed(); 711 } 712 713 size_t JfrStorage::clear_full() { 714 DiscardOperation discarder(mutexed); // a retired buffer implies mutexed access 715 const size_t count = process_full(discarder, control(), _age_mspace); 716 log(count, discarder.processed(), true); 717 return discarder.processed(); 718 } 719 720 static void scavenge_log(size_t count, size_t amount, size_t current) { 721 if (count > 0) { 722 if (log_is_enabled(Debug, jfr, system)) { 723 log_debug(jfr, system)("Released " SIZE_FORMAT " dead buffer(s) of " SIZE_FORMAT" B of data.", count, amount); 724 log_debug(jfr, system)("Current number of dead buffers " SIZE_FORMAT "", current); 725 } 726 } 727 } 728 729 template <typename Mspace> 730 class Scavenger { 731 private: 732 JfrStorageControl& _control; 733 Mspace* _mspace; 734 size_t _count; 735 size_t _amount; 736 public: 737 typedef typename Mspace::Type Type; 738 Scavenger(JfrStorageControl& control, Mspace* mspace) : _control(control), _mspace(mspace), _count(0), _amount(0) {} 739 bool process(Type* t) { 740 if (t->retired()) { 741 assert(!t->transient(), "invariant"); 742 assert(!t->lease(), "invariant"); 743 assert(t->empty(), "invariant"); 744 assert(t->identity() == NULL, "invariant"); 745 ++_count; 746 _amount += t->total_size(); 747 t->clear_retired(); 748 _control.decrement_dead(); 749 mspace_release_full_critical(t, _mspace); 750 } 751 return true; 752 } 753 size_t processed() const { return _count; } 754 size_t amount() const { return _amount; } 755 }; 756 757 size_t JfrStorage::scavenge() { 758 JfrStorageControl& ctrl = control(); 759 if (ctrl.dead_count() == 0) { 760 return 0; 761 } 762 Scavenger<JfrThreadLocalMspace> scavenger(ctrl, _thread_local_mspace); 763 process_full_list(scavenger, _thread_local_mspace); 764 scavenge_log(scavenger.processed(), scavenger.amount(), ctrl.dead_count()); 765 return scavenger.processed(); 766 }