Sat, 01 Sep 2012 13:25:18 -0400
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
1 /*
2 * Copyright (c) 1997, 2012, 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 */
25 #include "precompiled.hpp"
26 #include "code/codeBlob.hpp"
27 #include "code/codeCache.hpp"
28 #include "code/compiledIC.hpp"
29 #include "code/dependencies.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/nmethod.hpp"
32 #include "code/pcDesc.hpp"
33 #include "gc_implementation/shared/markSweep.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/gcLocker.hpp"
36 #include "memory/iterator.hpp"
37 #include "memory/resourceArea.hpp"
38 #include "oops/method.hpp"
39 #include "oops/objArrayOop.hpp"
40 #include "oops/oop.inline.hpp"
41 #include "runtime/handles.inline.hpp"
42 #include "runtime/icache.hpp"
43 #include "runtime/java.hpp"
44 #include "runtime/mutexLocker.hpp"
45 #include "services/memoryService.hpp"
46 #include "utilities/xmlstream.hpp"
48 // Helper class for printing in CodeCache
50 class CodeBlob_sizes {
51 private:
52 int count;
53 int total_size;
54 int header_size;
55 int code_size;
56 int stub_size;
57 int relocation_size;
58 int scopes_oop_size;
59 int scopes_metadata_size;
60 int scopes_data_size;
61 int scopes_pcs_size;
63 public:
64 CodeBlob_sizes() {
65 count = 0;
66 total_size = 0;
67 header_size = 0;
68 code_size = 0;
69 stub_size = 0;
70 relocation_size = 0;
71 scopes_oop_size = 0;
72 scopes_metadata_size = 0;
73 scopes_data_size = 0;
74 scopes_pcs_size = 0;
75 }
77 int total() { return total_size; }
78 bool is_empty() { return count == 0; }
80 void print(const char* title) {
81 tty->print_cr(" #%d %s = %dK (hdr %d%%, loc %d%%, code %d%%, stub %d%%, [oops %d%%, data %d%%, pcs %d%%])",
82 count,
83 title,
84 total() / K,
85 header_size * 100 / total_size,
86 relocation_size * 100 / total_size,
87 code_size * 100 / total_size,
88 stub_size * 100 / total_size,
89 scopes_oop_size * 100 / total_size,
90 scopes_metadata_size * 100 / total_size,
91 scopes_data_size * 100 / total_size,
92 scopes_pcs_size * 100 / total_size);
93 }
95 void add(CodeBlob* cb) {
96 count++;
97 total_size += cb->size();
98 header_size += cb->header_size();
99 relocation_size += cb->relocation_size();
100 if (cb->is_nmethod()) {
101 nmethod* nm = cb->as_nmethod_or_null();
102 code_size += nm->insts_size();
103 stub_size += nm->stub_size();
105 scopes_oop_size += nm->oops_size();
106 scopes_metadata_size += nm->metadata_size();
107 scopes_data_size += nm->scopes_data_size();
108 scopes_pcs_size += nm->scopes_pcs_size();
109 } else {
110 code_size += cb->code_size();
111 }
112 }
113 };
116 // CodeCache implementation
118 CodeHeap * CodeCache::_heap = new CodeHeap();
119 int CodeCache::_number_of_blobs = 0;
120 int CodeCache::_number_of_adapters = 0;
121 int CodeCache::_number_of_nmethods = 0;
122 int CodeCache::_number_of_nmethods_with_dependencies = 0;
123 bool CodeCache::_needs_cache_clean = false;
124 nmethod* CodeCache::_scavenge_root_nmethods = NULL;
125 nmethod* CodeCache::_saved_nmethods = NULL;
128 CodeBlob* CodeCache::first() {
129 assert_locked_or_safepoint(CodeCache_lock);
130 return (CodeBlob*)_heap->first();
131 }
134 CodeBlob* CodeCache::next(CodeBlob* cb) {
135 assert_locked_or_safepoint(CodeCache_lock);
136 return (CodeBlob*)_heap->next(cb);
137 }
140 CodeBlob* CodeCache::alive(CodeBlob *cb) {
141 assert_locked_or_safepoint(CodeCache_lock);
142 while (cb != NULL && !cb->is_alive()) cb = next(cb);
143 return cb;
144 }
147 nmethod* CodeCache::alive_nmethod(CodeBlob* cb) {
148 assert_locked_or_safepoint(CodeCache_lock);
149 while (cb != NULL && (!cb->is_alive() || !cb->is_nmethod())) cb = next(cb);
150 return (nmethod*)cb;
151 }
153 nmethod* CodeCache::first_nmethod() {
154 assert_locked_or_safepoint(CodeCache_lock);
155 CodeBlob* cb = first();
156 while (cb != NULL && !cb->is_nmethod()) {
157 cb = next(cb);
158 }
159 return (nmethod*)cb;
160 }
162 nmethod* CodeCache::next_nmethod (CodeBlob* cb) {
163 assert_locked_or_safepoint(CodeCache_lock);
164 cb = next(cb);
165 while (cb != NULL && !cb->is_nmethod()) {
166 cb = next(cb);
167 }
168 return (nmethod*)cb;
169 }
171 CodeBlob* CodeCache::allocate(int size) {
172 // Do not seize the CodeCache lock here--if the caller has not
173 // already done so, we are going to lose bigtime, since the code
174 // cache will contain a garbage CodeBlob until the caller can
175 // run the constructor for the CodeBlob subclass he is busy
176 // instantiating.
177 guarantee(size >= 0, "allocation request must be reasonable");
178 assert_locked_or_safepoint(CodeCache_lock);
179 CodeBlob* cb = NULL;
180 _number_of_blobs++;
181 while (true) {
182 cb = (CodeBlob*)_heap->allocate(size);
183 if (cb != NULL) break;
184 if (!_heap->expand_by(CodeCacheExpansionSize)) {
185 // Expansion failed
186 return NULL;
187 }
188 if (PrintCodeCacheExtension) {
189 ResourceMark rm;
190 tty->print_cr("code cache extended to [" INTPTR_FORMAT ", " INTPTR_FORMAT "] (%d bytes)",
191 (intptr_t)_heap->begin(), (intptr_t)_heap->end(),
192 (address)_heap->end() - (address)_heap->begin());
193 }
194 }
195 verify_if_often();
196 print_trace("allocation", cb, size);
197 return cb;
198 }
200 void CodeCache::free(CodeBlob* cb) {
201 assert_locked_or_safepoint(CodeCache_lock);
202 verify_if_often();
204 print_trace("free", cb);
205 if (cb->is_nmethod()) {
206 _number_of_nmethods--;
207 if (((nmethod *)cb)->has_dependencies()) {
208 _number_of_nmethods_with_dependencies--;
209 }
210 }
211 if (cb->is_adapter_blob()) {
212 _number_of_adapters--;
213 }
214 _number_of_blobs--;
216 _heap->deallocate(cb);
218 verify_if_often();
219 assert(_number_of_blobs >= 0, "sanity check");
220 }
223 void CodeCache::commit(CodeBlob* cb) {
224 // this is called by nmethod::nmethod, which must already own CodeCache_lock
225 assert_locked_or_safepoint(CodeCache_lock);
226 if (cb->is_nmethod()) {
227 _number_of_nmethods++;
228 if (((nmethod *)cb)->has_dependencies()) {
229 _number_of_nmethods_with_dependencies++;
230 }
231 }
232 if (cb->is_adapter_blob()) {
233 _number_of_adapters++;
234 }
236 // flush the hardware I-cache
237 ICache::invalidate_range(cb->content_begin(), cb->content_size());
238 }
241 void CodeCache::flush() {
242 assert_locked_or_safepoint(CodeCache_lock);
243 Unimplemented();
244 }
247 // Iteration over CodeBlobs
249 #define FOR_ALL_BLOBS(var) for (CodeBlob *var = first() ; var != NULL; var = next(var) )
250 #define FOR_ALL_ALIVE_BLOBS(var) for (CodeBlob *var = alive(first()); var != NULL; var = alive(next(var)))
251 #define FOR_ALL_ALIVE_NMETHODS(var) for (nmethod *var = alive_nmethod(first()); var != NULL; var = alive_nmethod(next(var)))
254 bool CodeCache::contains(void *p) {
255 // It should be ok to call contains without holding a lock
256 return _heap->contains(p);
257 }
260 // This method is safe to call without holding the CodeCache_lock, as long as a dead codeblob is not
261 // looked up (i.e., one that has been marked for deletion). It only dependes on the _segmap to contain
262 // valid indices, which it will always do, as long as the CodeBlob is not in the process of being recycled.
263 CodeBlob* CodeCache::find_blob(void* start) {
264 CodeBlob* result = find_blob_unsafe(start);
265 if (result == NULL) return NULL;
266 // We could potientially look up non_entrant methods
267 guarantee(!result->is_zombie() || result->is_locked_by_vm() || is_error_reported(), "unsafe access to zombie method");
268 return result;
269 }
271 nmethod* CodeCache::find_nmethod(void* start) {
272 CodeBlob *cb = find_blob(start);
273 assert(cb == NULL || cb->is_nmethod(), "did not find an nmethod");
274 return (nmethod*)cb;
275 }
278 void CodeCache::blobs_do(void f(CodeBlob* nm)) {
279 assert_locked_or_safepoint(CodeCache_lock);
280 FOR_ALL_BLOBS(p) {
281 f(p);
282 }
283 }
286 void CodeCache::nmethods_do(void f(nmethod* nm)) {
287 assert_locked_or_safepoint(CodeCache_lock);
288 FOR_ALL_BLOBS(nm) {
289 if (nm->is_nmethod()) f((nmethod*)nm);
290 }
291 }
293 void CodeCache::alive_nmethods_do(void f(nmethod* nm)) {
294 assert_locked_or_safepoint(CodeCache_lock);
295 FOR_ALL_ALIVE_NMETHODS(nm) {
296 f(nm);
297 }
298 }
300 int CodeCache::alignment_unit() {
301 return (int)_heap->alignment_unit();
302 }
305 int CodeCache::alignment_offset() {
306 return (int)_heap->alignment_offset();
307 }
310 // Mark nmethods for unloading if they contain otherwise unreachable
311 // oops.
312 void CodeCache::do_unloading(BoolObjectClosure* is_alive,
313 OopClosure* keep_alive,
314 bool unloading_occurred) {
315 assert_locked_or_safepoint(CodeCache_lock);
316 FOR_ALL_ALIVE_NMETHODS(nm) {
317 nm->do_unloading(is_alive, keep_alive, unloading_occurred);
318 }
319 }
321 void CodeCache::blobs_do(CodeBlobClosure* f) {
322 assert_locked_or_safepoint(CodeCache_lock);
323 FOR_ALL_ALIVE_BLOBS(cb) {
324 f->do_code_blob(cb);
326 #ifdef ASSERT
327 if (cb->is_nmethod())
328 ((nmethod*)cb)->verify_scavenge_root_oops();
329 #endif //ASSERT
330 }
331 }
333 // Walk the list of methods which might contain non-perm oops.
334 void CodeCache::scavenge_root_nmethods_do(CodeBlobClosure* f) {
335 assert_locked_or_safepoint(CodeCache_lock);
336 debug_only(mark_scavenge_root_nmethods());
338 for (nmethod* cur = scavenge_root_nmethods(); cur != NULL; cur = cur->scavenge_root_link()) {
339 debug_only(cur->clear_scavenge_root_marked());
340 assert(cur->scavenge_root_not_marked(), "");
341 assert(cur->on_scavenge_root_list(), "else shouldn't be on this list");
343 bool is_live = (!cur->is_zombie() && !cur->is_unloaded());
344 #ifndef PRODUCT
345 if (TraceScavenge) {
346 cur->print_on(tty, is_live ? "scavenge root" : "dead scavenge root"); tty->cr();
347 }
348 #endif //PRODUCT
349 if (is_live) {
350 // Perform cur->oops_do(f), maybe just once per nmethod.
351 f->do_code_blob(cur);
352 }
353 }
355 // Check for stray marks.
356 debug_only(verify_perm_nmethods(NULL));
357 }
359 void CodeCache::add_scavenge_root_nmethod(nmethod* nm) {
360 assert_locked_or_safepoint(CodeCache_lock);
361 nm->set_on_scavenge_root_list();
362 nm->set_scavenge_root_link(_scavenge_root_nmethods);
363 set_scavenge_root_nmethods(nm);
364 print_trace("add_scavenge_root", nm);
365 }
367 void CodeCache::drop_scavenge_root_nmethod(nmethod* nm) {
368 assert_locked_or_safepoint(CodeCache_lock);
369 print_trace("drop_scavenge_root", nm);
370 nmethod* last = NULL;
371 nmethod* cur = scavenge_root_nmethods();
372 while (cur != NULL) {
373 nmethod* next = cur->scavenge_root_link();
374 if (cur == nm) {
375 if (last != NULL)
376 last->set_scavenge_root_link(next);
377 else set_scavenge_root_nmethods(next);
378 nm->set_scavenge_root_link(NULL);
379 nm->clear_on_scavenge_root_list();
380 return;
381 }
382 last = cur;
383 cur = next;
384 }
385 assert(false, "should have been on list");
386 }
388 void CodeCache::prune_scavenge_root_nmethods() {
389 assert_locked_or_safepoint(CodeCache_lock);
390 debug_only(mark_scavenge_root_nmethods());
392 nmethod* last = NULL;
393 nmethod* cur = scavenge_root_nmethods();
394 while (cur != NULL) {
395 nmethod* next = cur->scavenge_root_link();
396 debug_only(cur->clear_scavenge_root_marked());
397 assert(cur->scavenge_root_not_marked(), "");
398 assert(cur->on_scavenge_root_list(), "else shouldn't be on this list");
400 if (!cur->is_zombie() && !cur->is_unloaded()
401 && cur->detect_scavenge_root_oops()) {
402 // Keep it. Advance 'last' to prevent deletion.
403 last = cur;
404 } else {
405 // Prune it from the list, so we don't have to look at it any more.
406 print_trace("prune_scavenge_root", cur);
407 cur->set_scavenge_root_link(NULL);
408 cur->clear_on_scavenge_root_list();
409 if (last != NULL)
410 last->set_scavenge_root_link(next);
411 else set_scavenge_root_nmethods(next);
412 }
413 cur = next;
414 }
416 // Check for stray marks.
417 debug_only(verify_perm_nmethods(NULL));
418 }
420 #ifndef PRODUCT
421 void CodeCache::asserted_non_scavengable_nmethods_do(CodeBlobClosure* f) {
422 // While we are here, verify the integrity of the list.
423 mark_scavenge_root_nmethods();
424 for (nmethod* cur = scavenge_root_nmethods(); cur != NULL; cur = cur->scavenge_root_link()) {
425 assert(cur->on_scavenge_root_list(), "else shouldn't be on this list");
426 cur->clear_scavenge_root_marked();
427 }
428 verify_perm_nmethods(f);
429 }
431 // Temporarily mark nmethods that are claimed to be on the non-perm list.
432 void CodeCache::mark_scavenge_root_nmethods() {
433 FOR_ALL_ALIVE_BLOBS(cb) {
434 if (cb->is_nmethod()) {
435 nmethod *nm = (nmethod*)cb;
436 assert(nm->scavenge_root_not_marked(), "clean state");
437 if (nm->on_scavenge_root_list())
438 nm->set_scavenge_root_marked();
439 }
440 }
441 }
443 // If the closure is given, run it on the unlisted nmethods.
444 // Also make sure that the effects of mark_scavenge_root_nmethods is gone.
445 void CodeCache::verify_perm_nmethods(CodeBlobClosure* f_or_null) {
446 FOR_ALL_ALIVE_BLOBS(cb) {
447 bool call_f = (f_or_null != NULL);
448 if (cb->is_nmethod()) {
449 nmethod *nm = (nmethod*)cb;
450 assert(nm->scavenge_root_not_marked(), "must be already processed");
451 if (nm->on_scavenge_root_list())
452 call_f = false; // don't show this one to the client
453 nm->verify_scavenge_root_oops();
454 } else {
455 call_f = false; // not an nmethod
456 }
457 if (call_f) f_or_null->do_code_blob(cb);
458 }
459 }
460 #endif //PRODUCT
463 nmethod* CodeCache::find_and_remove_saved_code(Method* m) {
464 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
465 nmethod* saved = _saved_nmethods;
466 nmethod* prev = NULL;
467 while (saved != NULL) {
468 if (saved->is_in_use() && saved->method() == m) {
469 if (prev != NULL) {
470 prev->set_saved_nmethod_link(saved->saved_nmethod_link());
471 } else {
472 _saved_nmethods = saved->saved_nmethod_link();
473 }
474 assert(saved->is_speculatively_disconnected(), "shouldn't call for other nmethods");
475 saved->set_speculatively_disconnected(false);
476 saved->set_saved_nmethod_link(NULL);
477 if (PrintMethodFlushing) {
478 saved->print_on(tty, " ### nmethod is reconnected\n");
479 }
480 if (LogCompilation && (xtty != NULL)) {
481 ttyLocker ttyl;
482 xtty->begin_elem("nmethod_reconnected compile_id='%3d'", saved->compile_id());
483 xtty->method(m);
484 xtty->stamp();
485 xtty->end_elem();
486 }
487 return saved;
488 }
489 prev = saved;
490 saved = saved->saved_nmethod_link();
491 }
492 return NULL;
493 }
495 void CodeCache::remove_saved_code(nmethod* nm) {
496 // For conc swpr this will be called with CodeCache_lock taken by caller
497 assert_locked_or_safepoint(CodeCache_lock);
498 assert(nm->is_speculatively_disconnected(), "shouldn't call for other nmethods");
499 nmethod* saved = _saved_nmethods;
500 nmethod* prev = NULL;
501 while (saved != NULL) {
502 if (saved == nm) {
503 if (prev != NULL) {
504 prev->set_saved_nmethod_link(saved->saved_nmethod_link());
505 } else {
506 _saved_nmethods = saved->saved_nmethod_link();
507 }
508 if (LogCompilation && (xtty != NULL)) {
509 ttyLocker ttyl;
510 xtty->begin_elem("nmethod_removed compile_id='%3d'", nm->compile_id());
511 xtty->stamp();
512 xtty->end_elem();
513 }
514 return;
515 }
516 prev = saved;
517 saved = saved->saved_nmethod_link();
518 }
519 ShouldNotReachHere();
520 }
522 void CodeCache::speculatively_disconnect(nmethod* nm) {
523 assert_locked_or_safepoint(CodeCache_lock);
524 assert(nm->is_in_use() && !nm->is_speculatively_disconnected(), "should only disconnect live nmethods");
525 nm->set_saved_nmethod_link(_saved_nmethods);
526 _saved_nmethods = nm;
527 if (PrintMethodFlushing) {
528 nm->print_on(tty, " ### nmethod is speculatively disconnected\n");
529 }
530 if (LogCompilation && (xtty != NULL)) {
531 ttyLocker ttyl;
532 xtty->begin_elem("nmethod_disconnected compile_id='%3d'", nm->compile_id());
533 xtty->method(nm->method());
534 xtty->stamp();
535 xtty->end_elem();
536 }
537 nm->method()->clear_code();
538 nm->set_speculatively_disconnected(true);
539 }
542 void CodeCache::gc_prologue() {
543 assert(!nmethod::oops_do_marking_is_active(), "oops_do_marking_epilogue must be called");
544 }
547 void CodeCache::gc_epilogue() {
548 assert_locked_or_safepoint(CodeCache_lock);
549 FOR_ALL_ALIVE_BLOBS(cb) {
550 if (cb->is_nmethod()) {
551 nmethod *nm = (nmethod*)cb;
552 assert(!nm->is_unloaded(), "Tautology");
553 if (needs_cache_clean()) {
554 nm->cleanup_inline_caches();
555 }
556 DEBUG_ONLY(nm->verify());
557 nm->fix_oop_relocations();
558 }
559 }
560 set_needs_cache_clean(false);
561 prune_scavenge_root_nmethods();
562 assert(!nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
564 #ifdef ASSERT
565 // make sure that we aren't leaking icholders
566 int count = 0;
567 FOR_ALL_BLOBS(cb) {
568 if (cb->is_nmethod()) {
569 RelocIterator iter((nmethod*)cb);
570 while(iter.next()) {
571 if (iter.type() == relocInfo::virtual_call_type) {
572 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc())) {
573 CompiledIC *ic = CompiledIC_at(iter.reloc());
574 if (TraceCompiledIC) {
575 tty->print("noticed icholder " INTPTR_FORMAT " ", ic->cached_icholder());
576 ic->print();
577 }
578 assert(ic->cached_icholder() != NULL, "must be non-NULL");
579 count++;
580 }
581 }
582 }
583 }
584 }
586 assert(count + InlineCacheBuffer::pending_icholder_count() + CompiledICHolder::live_not_claimed_count() ==
587 CompiledICHolder::live_count(), "must agree");
588 #endif
589 }
592 void CodeCache::verify_oops() {
593 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
594 VerifyOopClosure voc;
595 FOR_ALL_ALIVE_BLOBS(cb) {
596 if (cb->is_nmethod()) {
597 nmethod *nm = (nmethod*)cb;
598 nm->oops_do(&voc);
599 nm->verify_oop_relocations();
600 }
601 }
602 }
605 address CodeCache::first_address() {
606 assert_locked_or_safepoint(CodeCache_lock);
607 return (address)_heap->begin();
608 }
611 address CodeCache::last_address() {
612 assert_locked_or_safepoint(CodeCache_lock);
613 return (address)_heap->end();
614 }
617 void icache_init();
619 void CodeCache::initialize() {
620 assert(CodeCacheSegmentSize >= (uintx)CodeEntryAlignment, "CodeCacheSegmentSize must be large enough to align entry points");
621 #ifdef COMPILER2
622 assert(CodeCacheSegmentSize >= (uintx)OptoLoopAlignment, "CodeCacheSegmentSize must be large enough to align inner loops");
623 #endif
624 assert(CodeCacheSegmentSize >= sizeof(jdouble), "CodeCacheSegmentSize must be large enough to align constants");
625 // This was originally just a check of the alignment, causing failure, instead, round
626 // the code cache to the page size. In particular, Solaris is moving to a larger
627 // default page size.
628 CodeCacheExpansionSize = round_to(CodeCacheExpansionSize, os::vm_page_size());
629 InitialCodeCacheSize = round_to(InitialCodeCacheSize, os::vm_page_size());
630 ReservedCodeCacheSize = round_to(ReservedCodeCacheSize, os::vm_page_size());
631 if (!_heap->reserve(ReservedCodeCacheSize, InitialCodeCacheSize, CodeCacheSegmentSize)) {
632 vm_exit_during_initialization("Could not reserve enough space for code cache");
633 }
635 MemoryService::add_code_heap_memory_pool(_heap);
637 // Initialize ICache flush mechanism
638 // This service is needed for os::register_code_area
639 icache_init();
641 // Give OS a chance to register generated code area.
642 // This is used on Windows 64 bit platforms to register
643 // Structured Exception Handlers for our generated code.
644 os::register_code_area(_heap->low_boundary(), _heap->high_boundary());
645 }
648 void codeCache_init() {
649 CodeCache::initialize();
650 }
652 //------------------------------------------------------------------------------------------------
654 int CodeCache::number_of_nmethods_with_dependencies() {
655 return _number_of_nmethods_with_dependencies;
656 }
658 void CodeCache::clear_inline_caches() {
659 assert_locked_or_safepoint(CodeCache_lock);
660 FOR_ALL_ALIVE_NMETHODS(nm) {
661 nm->clear_inline_caches();
662 }
663 }
665 #ifndef PRODUCT
666 // used to keep track of how much time is spent in mark_for_deoptimization
667 static elapsedTimer dependentCheckTime;
668 static int dependentCheckCount = 0;
669 #endif // PRODUCT
672 int CodeCache::mark_for_deoptimization(DepChange& changes) {
673 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
675 #ifndef PRODUCT
676 dependentCheckTime.start();
677 dependentCheckCount++;
678 #endif // PRODUCT
680 int number_of_marked_CodeBlobs = 0;
682 // search the hierarchy looking for nmethods which are affected by the loading of this class
684 // then search the interfaces this class implements looking for nmethods
685 // which might be dependent of the fact that an interface only had one
686 // implementor.
688 { No_Safepoint_Verifier nsv;
689 for (DepChange::ContextStream str(changes, nsv); str.next(); ) {
690 Klass* d = str.klass();
691 number_of_marked_CodeBlobs += InstanceKlass::cast(d)->mark_dependent_nmethods(changes);
692 }
693 }
695 if (VerifyDependencies) {
696 // Turn off dependency tracing while actually testing deps.
697 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
698 FOR_ALL_ALIVE_NMETHODS(nm) {
699 if (!nm->is_marked_for_deoptimization() &&
700 nm->check_all_dependencies()) {
701 ResourceMark rm;
702 tty->print_cr("Should have been marked for deoptimization:");
703 changes.print();
704 nm->print();
705 nm->print_dependencies();
706 }
707 }
708 }
710 #ifndef PRODUCT
711 dependentCheckTime.stop();
712 #endif // PRODUCT
714 return number_of_marked_CodeBlobs;
715 }
718 #ifdef HOTSWAP
719 int CodeCache::mark_for_evol_deoptimization(instanceKlassHandle dependee) {
720 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
721 int number_of_marked_CodeBlobs = 0;
723 // Deoptimize all methods of the evolving class itself
724 Array<Method*>* old_methods = dependee->methods();
725 for (int i = 0; i < old_methods->length(); i++) {
726 ResourceMark rm;
727 Method* old_method = old_methods->at(i);
728 nmethod *nm = old_method->code();
729 if (nm != NULL) {
730 nm->mark_for_deoptimization();
731 number_of_marked_CodeBlobs++;
732 }
733 }
735 FOR_ALL_ALIVE_NMETHODS(nm) {
736 if (nm->is_marked_for_deoptimization()) {
737 // ...Already marked in the previous pass; don't count it again.
738 } else if (nm->is_evol_dependent_on(dependee())) {
739 ResourceMark rm;
740 nm->mark_for_deoptimization();
741 number_of_marked_CodeBlobs++;
742 } else {
743 // flush caches in case they refer to a redefined Method*
744 nm->clear_inline_caches();
745 }
746 }
748 return number_of_marked_CodeBlobs;
749 }
750 #endif // HOTSWAP
753 // Deoptimize all methods
754 void CodeCache::mark_all_nmethods_for_deoptimization() {
755 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
756 FOR_ALL_ALIVE_NMETHODS(nm) {
757 nm->mark_for_deoptimization();
758 }
759 }
762 int CodeCache::mark_for_deoptimization(Method* dependee) {
763 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
764 int number_of_marked_CodeBlobs = 0;
766 FOR_ALL_ALIVE_NMETHODS(nm) {
767 if (nm->is_dependent_on_method(dependee)) {
768 ResourceMark rm;
769 nm->mark_for_deoptimization();
770 number_of_marked_CodeBlobs++;
771 }
772 }
774 return number_of_marked_CodeBlobs;
775 }
777 void CodeCache::make_marked_nmethods_zombies() {
778 assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
779 FOR_ALL_ALIVE_NMETHODS(nm) {
780 if (nm->is_marked_for_deoptimization()) {
782 // If the nmethod has already been made non-entrant and it can be converted
783 // then zombie it now. Otherwise make it non-entrant and it will eventually
784 // be zombied when it is no longer seen on the stack. Note that the nmethod
785 // might be "entrant" and not on the stack and so could be zombied immediately
786 // but we can't tell because we don't track it on stack until it becomes
787 // non-entrant.
789 if (nm->is_not_entrant() && nm->can_not_entrant_be_converted()) {
790 nm->make_zombie();
791 } else {
792 nm->make_not_entrant();
793 }
794 }
795 }
796 }
798 void CodeCache::make_marked_nmethods_not_entrant() {
799 assert_locked_or_safepoint(CodeCache_lock);
800 FOR_ALL_ALIVE_NMETHODS(nm) {
801 if (nm->is_marked_for_deoptimization()) {
802 nm->make_not_entrant();
803 }
804 }
805 }
807 void CodeCache::verify() {
808 _heap->verify();
809 FOR_ALL_ALIVE_BLOBS(p) {
810 p->verify();
811 }
812 }
814 //------------------------------------------------------------------------------------------------
815 // Non-product version
817 #ifndef PRODUCT
819 void CodeCache::verify_if_often() {
820 if (VerifyCodeCacheOften) {
821 _heap->verify();
822 }
823 }
825 void CodeCache::print_trace(const char* event, CodeBlob* cb, int size) {
826 if (PrintCodeCache2) { // Need to add a new flag
827 ResourceMark rm;
828 if (size == 0) size = cb->size();
829 tty->print_cr("CodeCache %s: addr: " INTPTR_FORMAT ", size: 0x%x", event, cb, size);
830 }
831 }
833 void CodeCache::print_internals() {
834 int nmethodCount = 0;
835 int runtimeStubCount = 0;
836 int adapterCount = 0;
837 int deoptimizationStubCount = 0;
838 int uncommonTrapStubCount = 0;
839 int bufferBlobCount = 0;
840 int total = 0;
841 int nmethodAlive = 0;
842 int nmethodNotEntrant = 0;
843 int nmethodZombie = 0;
844 int nmethodUnloaded = 0;
845 int nmethodJava = 0;
846 int nmethodNative = 0;
847 int maxCodeSize = 0;
848 ResourceMark rm;
850 CodeBlob *cb;
851 for (cb = first(); cb != NULL; cb = next(cb)) {
852 total++;
853 if (cb->is_nmethod()) {
854 nmethod* nm = (nmethod*)cb;
856 if (Verbose && nm->method() != NULL) {
857 ResourceMark rm;
858 char *method_name = nm->method()->name_and_sig_as_C_string();
859 tty->print("%s", method_name);
860 if(nm->is_alive()) { tty->print_cr(" alive"); }
861 if(nm->is_not_entrant()) { tty->print_cr(" not-entrant"); }
862 if(nm->is_zombie()) { tty->print_cr(" zombie"); }
863 }
865 nmethodCount++;
867 if(nm->is_alive()) { nmethodAlive++; }
868 if(nm->is_not_entrant()) { nmethodNotEntrant++; }
869 if(nm->is_zombie()) { nmethodZombie++; }
870 if(nm->is_unloaded()) { nmethodUnloaded++; }
871 if(nm->is_native_method()) { nmethodNative++; }
873 if(nm->method() != NULL && nm->is_java_method()) {
874 nmethodJava++;
875 if (nm->insts_size() > maxCodeSize) {
876 maxCodeSize = nm->insts_size();
877 }
878 }
879 } else if (cb->is_runtime_stub()) {
880 runtimeStubCount++;
881 } else if (cb->is_deoptimization_stub()) {
882 deoptimizationStubCount++;
883 } else if (cb->is_uncommon_trap_stub()) {
884 uncommonTrapStubCount++;
885 } else if (cb->is_adapter_blob()) {
886 adapterCount++;
887 } else if (cb->is_buffer_blob()) {
888 bufferBlobCount++;
889 }
890 }
892 int bucketSize = 512;
893 int bucketLimit = maxCodeSize / bucketSize + 1;
894 int *buckets = NEW_C_HEAP_ARRAY(int, bucketLimit, mtCode);
895 memset(buckets,0,sizeof(int) * bucketLimit);
897 for (cb = first(); cb != NULL; cb = next(cb)) {
898 if (cb->is_nmethod()) {
899 nmethod* nm = (nmethod*)cb;
900 if(nm->is_java_method()) {
901 buckets[nm->insts_size() / bucketSize]++;
902 }
903 }
904 }
905 tty->print_cr("Code Cache Entries (total of %d)",total);
906 tty->print_cr("-------------------------------------------------");
907 tty->print_cr("nmethods: %d",nmethodCount);
908 tty->print_cr("\talive: %d",nmethodAlive);
909 tty->print_cr("\tnot_entrant: %d",nmethodNotEntrant);
910 tty->print_cr("\tzombie: %d",nmethodZombie);
911 tty->print_cr("\tunloaded: %d",nmethodUnloaded);
912 tty->print_cr("\tjava: %d",nmethodJava);
913 tty->print_cr("\tnative: %d",nmethodNative);
914 tty->print_cr("runtime_stubs: %d",runtimeStubCount);
915 tty->print_cr("adapters: %d",adapterCount);
916 tty->print_cr("buffer blobs: %d",bufferBlobCount);
917 tty->print_cr("deoptimization_stubs: %d",deoptimizationStubCount);
918 tty->print_cr("uncommon_traps: %d",uncommonTrapStubCount);
919 tty->print_cr("\nnmethod size distribution (non-zombie java)");
920 tty->print_cr("-------------------------------------------------");
922 for(int i=0; i<bucketLimit; i++) {
923 if(buckets[i] != 0) {
924 tty->print("%d - %d bytes",i*bucketSize,(i+1)*bucketSize);
925 tty->fill_to(40);
926 tty->print_cr("%d",buckets[i]);
927 }
928 }
930 FREE_C_HEAP_ARRAY(int, buckets, mtCode);
931 }
933 void CodeCache::print() {
934 CodeBlob_sizes live;
935 CodeBlob_sizes dead;
937 FOR_ALL_BLOBS(p) {
938 if (!p->is_alive()) {
939 dead.add(p);
940 } else {
941 live.add(p);
942 }
943 }
945 tty->print_cr("CodeCache:");
947 tty->print_cr("nmethod dependency checking time %f", dependentCheckTime.seconds(),
948 dependentCheckTime.seconds() / dependentCheckCount);
950 if (!live.is_empty()) {
951 live.print("live");
952 }
953 if (!dead.is_empty()) {
954 dead.print("dead");
955 }
958 if (Verbose) {
959 // print the oop_map usage
960 int code_size = 0;
961 int number_of_blobs = 0;
962 int number_of_oop_maps = 0;
963 int map_size = 0;
964 FOR_ALL_BLOBS(p) {
965 if (p->is_alive()) {
966 number_of_blobs++;
967 code_size += p->code_size();
968 OopMapSet* set = p->oop_maps();
969 if (set != NULL) {
970 number_of_oop_maps += set->size();
971 map_size += set->heap_size();
972 }
973 }
974 }
975 tty->print_cr("OopMaps");
976 tty->print_cr(" #blobs = %d", number_of_blobs);
977 tty->print_cr(" code size = %d", code_size);
978 tty->print_cr(" #oop_maps = %d", number_of_oop_maps);
979 tty->print_cr(" map size = %d", map_size);
980 }
982 }
984 #endif // PRODUCT
986 void CodeCache::print_bounds(outputStream* st) {
987 st->print_cr("Code Cache [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " INTPTR_FORMAT ")",
988 _heap->low_boundary(),
989 _heap->high(),
990 _heap->high_boundary());
991 st->print_cr(" total_blobs=" UINT32_FORMAT " nmethods=" UINT32_FORMAT
992 " adapters=" UINT32_FORMAT " free_code_cache=" SIZE_FORMAT "Kb"
993 " largest_free_block=" SIZE_FORMAT,
994 nof_blobs(), nof_nmethods(), nof_adapters(),
995 unallocated_capacity()/K, largest_free_block());
996 }
998 void CodeCache::log_state(outputStream* st) {
999 st->print(" total_blobs='" UINT32_FORMAT "' nmethods='" UINT32_FORMAT "'"
1000 " adapters='" UINT32_FORMAT "' free_code_cache='" SIZE_FORMAT "'"
1001 " largest_free_block='" SIZE_FORMAT "'",
1002 nof_blobs(), nof_nmethods(), nof_adapters(),
1003 unallocated_capacity(), largest_free_block());
1004 }
1006 size_t CodeCache::largest_free_block() {
1007 // This is called both with and without CodeCache_lock held so
1008 // handle both cases.
1009 if (CodeCache_lock->owned_by_self()) {
1010 return _heap->largest_free_block();
1011 } else {
1012 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1013 return _heap->largest_free_block();
1014 }
1015 }