1 /* 2 * Copyright (c) 1997, 2013, 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 "code/codeCache.hpp" 27 #include "code/compiledIC.hpp" 28 #include "code/icBuffer.hpp" 29 #include "code/nmethod.hpp" 30 #include "compiler/compileBroker.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "oops/method.hpp" 33 #include "runtime/atomic.hpp" 34 #include "runtime/compilationPolicy.hpp" 35 #include "runtime/mutexLocker.hpp" 36 #include "runtime/os.hpp" 37 #include "runtime/sweeper.hpp" 38 #include "runtime/vm_operations.hpp" 39 #include "trace/tracing.hpp" 40 #include "utilities/events.hpp" 41 #include "utilities/xmlstream.hpp" 42 43 #ifdef ASSERT 44 45 #define SWEEP(nm) record_sweep(nm, __LINE__) 46 // Sweeper logging code 47 class SweeperRecord { 48 public: 49 int traversal; 50 int invocation; 51 int compile_id; 52 long traversal_mark; 53 int state; 54 const char* kind; 55 address vep; 56 address uep; 57 int line; 58 59 void print() { 60 tty->print_cr("traversal = %d invocation = %d compile_id = %d %s uep = " PTR_FORMAT " vep = " 61 PTR_FORMAT " state = %d traversal_mark %d line = %d", 62 traversal, 63 invocation, 64 compile_id, 65 kind == NULL ? "" : kind, 66 uep, 67 vep, 68 state, 69 traversal_mark, 70 line); 71 } 72 }; 73 74 static int _sweep_index = 0; 75 static SweeperRecord* _records = NULL; 76 77 void NMethodSweeper::report_events(int id, address entry) { 78 if (_records != NULL) { 79 for (int i = _sweep_index; i < SweeperLogEntries; i++) { 80 if (_records[i].uep == entry || 81 _records[i].vep == entry || 82 _records[i].compile_id == id) { 83 _records[i].print(); 84 } 85 } 86 for (int i = 0; i < _sweep_index; i++) { 87 if (_records[i].uep == entry || 88 _records[i].vep == entry || 89 _records[i].compile_id == id) { 90 _records[i].print(); 91 } 92 } 93 } 94 } 95 96 void NMethodSweeper::report_events() { 97 if (_records != NULL) { 98 for (int i = _sweep_index; i < SweeperLogEntries; i++) { 99 // skip empty records 100 if (_records[i].vep == NULL) continue; 101 _records[i].print(); 102 } 103 for (int i = 0; i < _sweep_index; i++) { 104 // skip empty records 105 if (_records[i].vep == NULL) continue; 106 _records[i].print(); 107 } 108 } 109 } 110 111 void NMethodSweeper::record_sweep(nmethod* nm, int line) { 112 if (_records != NULL) { 113 _records[_sweep_index].traversal = _traversals; 114 _records[_sweep_index].traversal_mark = nm->_stack_traversal_mark; 115 _records[_sweep_index].invocation = _invocations; 116 _records[_sweep_index].compile_id = nm->compile_id(); 117 _records[_sweep_index].kind = nm->compile_kind(); 118 _records[_sweep_index].state = nm->_state; 119 _records[_sweep_index].vep = nm->verified_entry_point(); 120 _records[_sweep_index].uep = nm->entry_point(); 121 _records[_sweep_index].line = line; 122 123 _sweep_index = (_sweep_index + 1) % SweeperLogEntries; 124 } 125 } 126 #else 127 #define SWEEP(nm) 128 #endif 129 130 131 long NMethodSweeper::_traversals = 0; // No. of stack traversals performed 132 nmethod* NMethodSweeper::_current = NULL; // Current nmethod 133 int NMethodSweeper::_seen = 0 ; // No. of nmethods we have currently processed in current pass of CodeCache 134 int NMethodSweeper::_flushed_count = 0; // Nof. nmethods flushed in current sweep 135 int NMethodSweeper::_zombified_count = 0; // Nof. nmethods made zombie in current sweep 136 int NMethodSweeper::_marked_count = 0; // Nof. nmethods marked for reclaim in current sweep 137 138 volatile int NMethodSweeper::_invocations = 0; // No. of invocations left until we are completed with this pass 139 volatile int NMethodSweeper::_sweep_started = 0; // Whether a sweep is in progress. 140 141 jint NMethodSweeper::_locked_seen = 0; 142 jint NMethodSweeper::_not_entrant_seen_on_stack = 0; 143 bool NMethodSweeper::_resweep = false; 144 jint NMethodSweeper::_flush_token = 0; 145 jlong NMethodSweeper::_last_full_flush_time = 0; 146 int NMethodSweeper::_highest_marked = 0; 147 int NMethodSweeper::_dead_compile_ids = 0; 148 long NMethodSweeper::_last_flush_traversal_id = 0; 149 150 int NMethodSweeper::_number_of_flushes = 0; // Total of full traversals caused by full cache 151 int NMethodSweeper::_total_nof_methods_reclaimed = 0; 152 jlong NMethodSweeper::_total_time_sweeping = 0; 153 jlong NMethodSweeper::_total_time_this_sweep = 0; 154 jlong NMethodSweeper::_peak_sweep_time = 0; 155 jlong NMethodSweeper::_peak_sweep_fraction_time = 0; 156 jlong NMethodSweeper::_total_disconnect_time = 0; 157 jlong NMethodSweeper::_peak_disconnect_time = 0; 158 159 class MarkActivationClosure: public CodeBlobClosure { 160 public: 161 virtual void do_code_blob(CodeBlob* cb) { 162 // If we see an activation belonging to a non_entrant nmethod, we mark it. 163 if (cb->is_nmethod() && ((nmethod*)cb)->is_not_entrant()) { 164 ((nmethod*)cb)->mark_as_seen_on_stack(); 165 } 166 } 167 }; 168 static MarkActivationClosure mark_activation_closure; 169 170 bool NMethodSweeper::sweep_in_progress() { 171 return (_current != NULL); 172 } 173 174 void NMethodSweeper::scan_stacks() { 175 assert(SafepointSynchronize::is_at_safepoint(), "must be executed at a safepoint"); 176 if (!MethodFlushing) return; 177 178 // No need to synchronize access, since this is always executed at a 179 // safepoint. 180 181 // Make sure CompiledIC_lock in unlocked, since we might update some 182 // inline caches. If it is, we just bail-out and try later. 183 if (CompiledIC_lock->is_locked() || Patching_lock->is_locked()) return; 184 185 // Check for restart 186 assert(CodeCache::find_blob_unsafe(_current) == _current, "Sweeper nmethod cached state invalid"); 187 if (!sweep_in_progress() && _resweep) { 188 _seen = 0; 189 _invocations = NmethodSweepFraction; 190 _current = CodeCache::first_nmethod(); 191 _traversals += 1; 192 _total_time_this_sweep = 0; 193 194 if (PrintMethodFlushing) { 195 tty->print_cr("### Sweep: stack traversal %d", _traversals); 196 } 197 Threads::nmethods_do(&mark_activation_closure); 198 199 // reset the flags since we started a scan from the beginning. 200 _resweep = false; 201 _locked_seen = 0; 202 _not_entrant_seen_on_stack = 0; 203 } 204 205 if (UseCodeCacheFlushing) { 206 // only allow new flushes after the interval is complete. 207 jlong now = os::javaTimeMillis(); 208 jlong max_interval = (jlong)MinCodeCacheFlushingInterval * (jlong)1000; 209 jlong curr_interval = now - _last_full_flush_time; 210 if (curr_interval > max_interval) { 211 _flush_token = 0; 212 } 213 214 if (!CodeCache::needs_flushing() && !CompileBroker::should_compile_new_jobs()) { 215 CompileBroker::set_should_compile_new_jobs(CompileBroker::run_compilation); 216 log_sweep("restart_compiler"); 217 } 218 } 219 } 220 221 void NMethodSweeper::possibly_sweep() { 222 assert(JavaThread::current()->thread_state() == _thread_in_vm, "must run in vm mode"); 223 if (!MethodFlushing || !sweep_in_progress()) return; 224 225 if (_invocations > 0) { 226 // Only one thread at a time will sweep 227 jint old = Atomic::cmpxchg( 1, &_sweep_started, 0 ); 228 if (old != 0) { 229 return; 230 } 231 #ifdef ASSERT 232 if (LogSweeper && _records == NULL) { 233 // Create the ring buffer for the logging code 234 _records = NEW_C_HEAP_ARRAY(SweeperRecord, SweeperLogEntries, mtGC); 235 memset(_records, 0, sizeof(SweeperRecord) * SweeperLogEntries); 236 } 237 #endif 238 if (_invocations > 0) { 239 sweep_code_cache(); 240 _invocations--; 241 } 242 _sweep_started = 0; 243 } 244 } 245 246 void NMethodSweeper::sweep_code_cache() { 247 248 jlong sweep_start_counter = os::elapsed_counter(); 249 250 _flushed_count = 0; 251 _zombified_count = 0; 252 _marked_count = 0; 253 254 if (PrintMethodFlushing && Verbose) { 255 tty->print_cr("### Sweep at %d out of %d. Invocations left: %d", _seen, CodeCache::nof_nmethods(), _invocations); 256 } 257 258 if (!CompileBroker::should_compile_new_jobs()) { 259 // If we have turned off compilations we might as well do full sweeps 260 // in order to reach the clean state faster. Otherwise the sleeping compiler 261 // threads will slow down sweeping. After a few iterations the cache 262 // will be clean and sweeping stops (_resweep will not be set) 263 _invocations = 1; 264 } 265 266 // We want to visit all nmethods after NmethodSweepFraction 267 // invocations so divide the remaining number of nmethods by the 268 // remaining number of invocations. This is only an estimate since 269 // the number of nmethods changes during the sweep so the final 270 // stage must iterate until it there are no more nmethods. 271 int todo = (CodeCache::nof_nmethods() - _seen) / _invocations; 272 int swept_count = 0; 273 274 assert(!SafepointSynchronize::is_at_safepoint(), "should not be in safepoint when we get here"); 275 assert(!CodeCache_lock->owned_by_self(), "just checking"); 276 277 { 278 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 279 280 // The last invocation iterates until there are no more nmethods 281 for (int i = 0; (i < todo || _invocations == 1) && _current != NULL; i++) { 282 swept_count++; 283 if (SafepointSynchronize::is_synchronizing()) { // Safepoint request 284 if (PrintMethodFlushing && Verbose) { 285 tty->print_cr("### Sweep at %d out of %d, invocation: %d, yielding to safepoint", _seen, CodeCache::nof_nmethods(), _invocations); 286 } 287 MutexUnlockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 288 289 assert(Thread::current()->is_Java_thread(), "should be java thread"); 290 JavaThread* thread = (JavaThread*)Thread::current(); 291 ThreadBlockInVM tbivm(thread); 292 thread->java_suspend_self(); 293 } 294 // Since we will give up the CodeCache_lock, always skip ahead 295 // to the next nmethod. Other blobs can be deleted by other 296 // threads but nmethods are only reclaimed by the sweeper. 297 nmethod* next = CodeCache::next_nmethod(_current); 298 299 // Now ready to process nmethod and give up CodeCache_lock 300 { 301 MutexUnlockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 302 process_nmethod(_current); 303 } 304 _seen++; 305 _current = next; 306 } 307 } 308 309 assert(_invocations > 1 || _current == NULL, "must have scanned the whole cache"); 310 311 if (!sweep_in_progress() && !_resweep && (_locked_seen || _not_entrant_seen_on_stack)) { 312 // we've completed a scan without making progress but there were 313 // nmethods we were unable to process either because they were 314 // locked or were still on stack. We don't have to aggresively 315 // clean them up so just stop scanning. We could scan once more 316 // but that complicates the control logic and it's unlikely to 317 // matter much. 318 if (PrintMethodFlushing) { 319 tty->print_cr("### Couldn't make progress on some nmethods so stopping sweep"); 320 } 321 } 322 323 jlong sweep_end_counter = os::elapsed_counter(); 324 jlong sweep_time = sweep_end_counter - sweep_start_counter; 325 _total_time_sweeping += sweep_time; 326 _total_time_this_sweep += sweep_time; 327 _peak_sweep_fraction_time = MAX2(sweep_time, _peak_sweep_fraction_time); 328 _total_nof_methods_reclaimed += _flushed_count; 329 330 EventSweepCodeCache event(UNTIMED); 331 if (event.should_commit()) { 332 event.set_starttime(sweep_start_counter); 333 event.set_endtime(sweep_end_counter); 334 event.set_sweepIndex(_traversals); 335 event.set_sweepFractionIndex(NmethodSweepFraction - _invocations + 1); 336 event.set_sweptCount(swept_count); 337 event.set_flushedCount(_flushed_count); 338 event.set_markedCount(_marked_count); 339 event.set_zombifiedCount(_zombified_count); 340 event.commit(); 341 } 342 343 #ifdef ASSERT 344 if(PrintMethodFlushing) { 345 tty->print_cr("### sweeper: sweep time(%d): " INT64_FORMAT, _invocations, (jlong)sweep_time); 346 } 347 #endif 348 349 if (_invocations == 1) { 350 _peak_sweep_time = MAX2(_peak_sweep_time, _total_time_this_sweep); 351 log_sweep("finished"); 352 } 353 354 // Sweeper is the only case where memory is released, 355 // check here if it is time to restart the compiler. 356 if (UseCodeCacheFlushing && !CompileBroker::should_compile_new_jobs() && !CodeCache::needs_flushing()) { 357 CompileBroker::set_should_compile_new_jobs(CompileBroker::run_compilation); 358 log_sweep("restart_compiler"); 359 } 360 } 361 362 class NMethodMarker: public StackObj { 363 private: 364 CompilerThread* _thread; 365 public: 366 NMethodMarker(nmethod* nm) { 367 _thread = CompilerThread::current(); 368 if (!nm->is_zombie() && !nm->is_unloaded()) { 369 // Only expose live nmethods for scanning 370 _thread->set_scanned_nmethod(nm); 371 } 372 } 373 ~NMethodMarker() { 374 _thread->set_scanned_nmethod(NULL); 375 } 376 }; 377 378 void NMethodSweeper::release_nmethod(nmethod *nm) { 379 // Clean up any CompiledICHolders 380 { 381 ResourceMark rm; 382 MutexLocker ml_patch(CompiledIC_lock); 383 RelocIterator iter(nm); 384 while (iter.next()) { 385 if (iter.type() == relocInfo::virtual_call_type) { 386 CompiledIC::cleanup_call_site(iter.virtual_call_reloc()); 387 } 388 } 389 } 390 391 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); 392 nm->flush(); 393 } 394 395 void NMethodSweeper::process_nmethod(nmethod *nm) { 396 assert(!CodeCache_lock->owned_by_self(), "just checking"); 397 398 // Make sure this nmethod doesn't get unloaded during the scan, 399 // since the locks acquired below might safepoint. 400 NMethodMarker nmm(nm); 401 402 SWEEP(nm); 403 404 // Skip methods that are currently referenced by the VM 405 if (nm->is_locked_by_vm()) { 406 // But still remember to clean-up inline caches for alive nmethods 407 if (nm->is_alive()) { 408 // Clean-up all inline caches that points to zombie/non-reentrant methods 409 MutexLocker cl(CompiledIC_lock); 410 nm->cleanup_inline_caches(); 411 SWEEP(nm); 412 } else { 413 _locked_seen++; 414 SWEEP(nm); 415 } 416 return; 417 } 418 419 if (nm->is_zombie()) { 420 // If it is first time, we see nmethod then we mark it. Otherwise, 421 // we reclame it. When we have seen a zombie method twice, we know that 422 // there are no inline caches that refer to it. 423 if (nm->is_marked_for_reclamation()) { 424 assert(!nm->is_locked_by_vm(), "must not flush locked nmethods"); 425 if (PrintMethodFlushing && Verbose) { 426 tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (marked for reclamation) being flushed", nm->compile_id(), nm); 427 } 428 release_nmethod(nm); 429 _flushed_count++; 430 } else { 431 if (PrintMethodFlushing && Verbose) { 432 tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (zombie) being marked for reclamation", nm->compile_id(), nm); 433 } 434 nm->mark_for_reclamation(); 435 _resweep = true; 436 _marked_count++; 437 SWEEP(nm); 438 } 439 } else if (nm->is_not_entrant()) { 440 // If there is no current activations of this method on the 441 // stack we can safely convert it to a zombie method 442 if (nm->can_not_entrant_be_converted()) { 443 if (PrintMethodFlushing && Verbose) { 444 tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (not entrant) being made zombie", nm->compile_id(), nm); 445 } 446 nm->make_zombie(); 447 _resweep = true; 448 _zombified_count++; 449 SWEEP(nm); 450 } else { 451 // Still alive, clean up its inline caches 452 MutexLocker cl(CompiledIC_lock); 453 nm->cleanup_inline_caches(); 454 // we coudn't transition this nmethod so don't immediately 455 // request a rescan. If this method stays on the stack for a 456 // long time we don't want to keep rescanning the code cache. 457 _not_entrant_seen_on_stack++; 458 SWEEP(nm); 459 } 460 } else if (nm->is_unloaded()) { 461 // Unloaded code, just make it a zombie 462 if (PrintMethodFlushing && Verbose) 463 tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (unloaded) being made zombie", nm->compile_id(), nm); 464 465 if (nm->is_osr_method()) { 466 SWEEP(nm); 467 // No inline caches will ever point to osr methods, so we can just remove it 468 release_nmethod(nm); 469 _flushed_count++; 470 } else { 471 nm->make_zombie(); 472 _resweep = true; 473 _zombified_count++; 474 SWEEP(nm); 475 } 476 } else { 477 assert(nm->is_alive(), "should be alive"); 478 479 if (UseCodeCacheFlushing) { 480 if (nm->is_speculatively_disconnected() && !nm->is_locked_by_vm() && !nm->is_osr_method() && 481 (_traversals > _last_flush_traversal_id + 2) && (nm->compile_id() < _highest_marked)) { 482 // This method has not been called since the forced cleanup happened 483 nm->make_not_entrant(); 484 } 485 } 486 487 // Clean-up all inline caches that points to zombie/non-reentrant methods 488 MutexLocker cl(CompiledIC_lock); 489 nm->cleanup_inline_caches(); 490 SWEEP(nm); 491 } 492 } 493 494 // Code cache unloading: when compilers notice the code cache is getting full, 495 // they will call a vm op that comes here. This code attempts to speculatively 496 // unload the oldest half of the nmethods (based on the compile job id) by 497 // saving the old code in a list in the CodeCache. Then 498 // execution resumes. If a method so marked is not called by the second sweeper 499 // stack traversal after the current one, the nmethod will be marked non-entrant and 500 // got rid of by normal sweeping. If the method is called, the Method*'s 501 // _code field is restored and the Method*/nmethod 502 // go back to their normal state. 503 void NMethodSweeper::handle_full_code_cache(bool is_full) { 504 505 if (is_full) { 506 // Since code cache is full, immediately stop new compiles 507 if (CompileBroker::set_should_compile_new_jobs(CompileBroker::stop_compilation)) { 508 log_sweep("disable_compiler"); 509 } 510 } 511 512 // Make sure only one thread can flush 513 // The token is reset after CodeCacheMinimumFlushInterval in scan stacks, 514 // no need to check the timeout here. 515 jint old = Atomic::cmpxchg( 1, &_flush_token, 0 ); 516 if (old != 0) { 517 return; 518 } 519 520 VM_HandleFullCodeCache op(is_full); 521 VMThread::execute(&op); 522 523 // resweep again as soon as possible 524 _resweep = true; 525 } 526 527 void NMethodSweeper::speculative_disconnect_nmethods(bool is_full) { 528 // If there was a race in detecting full code cache, only run 529 // one vm op for it or keep the compiler shut off 530 531 jlong disconnect_start_counter = os::elapsed_counter(); 532 533 // Traverse the code cache trying to dump the oldest nmethods 534 int curr_max_comp_id = CompileBroker::get_compilation_id(); 535 int flush_target = ((curr_max_comp_id - _dead_compile_ids) / CodeCacheFlushingFraction) + _dead_compile_ids; 536 537 log_sweep("start_cleaning"); 538 539 nmethod* nm = CodeCache::alive_nmethod(CodeCache::first()); 540 jint disconnected = 0; 541 jint made_not_entrant = 0; 542 jint nmethod_count = 0; 543 544 while ((nm != NULL)){ 545 int curr_comp_id = nm->compile_id(); 546 547 // OSR methods cannot be flushed like this. Also, don't flush native methods 548 // since they are part of the JDK in most cases 549 if (!nm->is_osr_method() && !nm->is_locked_by_vm() && !nm->is_native_method()) { 550 551 // only count methods that can be speculatively disconnected 552 nmethod_count++; 553 554 if (nm->is_in_use() && (curr_comp_id < flush_target)) { 555 if ((nm->method()->code() == nm)) { 556 // This method has not been previously considered for 557 // unloading or it was restored already 558 CodeCache::speculatively_disconnect(nm); 559 disconnected++; 560 } else if (nm->is_speculatively_disconnected()) { 561 // This method was previously considered for preemptive unloading and was not called since then 562 CompilationPolicy::policy()->delay_compilation(nm->method()); 563 nm->make_not_entrant(); 564 made_not_entrant++; 565 } 566 567 if (curr_comp_id > _highest_marked) { 568 _highest_marked = curr_comp_id; 569 } 570 } 571 } 572 nm = CodeCache::alive_nmethod(CodeCache::next(nm)); 573 } 574 575 // remember how many compile_ids wheren't seen last flush. 576 _dead_compile_ids = curr_max_comp_id - nmethod_count; 577 578 log_sweep("stop_cleaning", 579 "disconnected='" UINT32_FORMAT "' made_not_entrant='" UINT32_FORMAT "'", 580 disconnected, made_not_entrant); 581 582 // Shut off compiler. Sweeper will start over with a new stack scan and 583 // traversal cycle and turn it back on if it clears enough space. 584 if (is_full) { 585 _last_full_flush_time = os::javaTimeMillis(); 586 } 587 588 jlong disconnect_end_counter = os::elapsed_counter(); 589 jlong disconnect_time = disconnect_end_counter - disconnect_start_counter; 590 _total_disconnect_time += disconnect_time; 591 _peak_disconnect_time = MAX2(disconnect_time, _peak_disconnect_time); 592 593 EventCleanCodeCache event(UNTIMED); 594 if (event.should_commit()) { 595 event.set_starttime(disconnect_start_counter); 596 event.set_endtime(disconnect_end_counter); 597 event.set_disconnectedCount(disconnected); 598 event.set_madeNonEntrantCount(made_not_entrant); 599 event.commit(); 600 } 601 _number_of_flushes++; 602 603 // After two more traversals the sweeper will get rid of unrestored nmethods 604 _last_flush_traversal_id = _traversals; 605 _resweep = true; 606 #ifdef ASSERT 607 608 if(PrintMethodFlushing && Verbose) { 609 tty->print_cr("### sweeper: unload time: " INT64_FORMAT, (jlong)disconnect_time); 610 } 611 #endif 612 } 613 614 615 // Print out some state information about the current sweep and the 616 // state of the code cache if it's requested. 617 void NMethodSweeper::log_sweep(const char* msg, const char* format, ...) { 618 if (PrintMethodFlushing) { 619 stringStream s; 620 // Dump code cache state into a buffer before locking the tty, 621 // because log_state() will use locks causing lock conflicts. 622 CodeCache::log_state(&s); 623 624 ttyLocker ttyl; 625 tty->print("### sweeper: %s ", msg); 626 if (format != NULL) { 627 va_list ap; 628 va_start(ap, format); 629 tty->vprint(format, ap); 630 va_end(ap); 631 } 632 tty->print_cr(s.as_string()); 633 } 634 635 if (LogCompilation && (xtty != NULL)) { 636 stringStream s; 637 // Dump code cache state into a buffer before locking the tty, 638 // because log_state() will use locks causing lock conflicts. 639 CodeCache::log_state(&s); 640 641 ttyLocker ttyl; 642 xtty->begin_elem("sweeper state='%s' traversals='" INTX_FORMAT "' ", msg, (intx)traversal_count()); 643 if (format != NULL) { 644 va_list ap; 645 va_start(ap, format); 646 xtty->vprint(format, ap); 647 va_end(ap); 648 } 649 xtty->print(s.as_string()); 650 xtty->stamp(); 651 xtty->end_elem(); 652 } 653 }