Mercurial > hg > truffle
annotate src/share/vm/runtime/jniHandles.cpp @ 4724:0841c0ec2ed6
7123810: new hotspot build - hs23-b10
Reviewed-by: jcoomes
author | amurillo |
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date | Fri, 23 Dec 2011 15:29:34 -0800 |
parents | f08d439fab8c |
children | da91efe96a93 |
rev | line source |
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0 | 1 /* |
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2 * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 #include "precompiled.hpp" |
26 #include "classfile/systemDictionary.hpp" | |
27 #include "oops/oop.inline.hpp" | |
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28 #include "prims/jvmtiExport.hpp" |
1972 | 29 #include "runtime/jniHandles.hpp" |
30 #include "runtime/mutexLocker.hpp" | |
31 #ifdef TARGET_OS_FAMILY_linux | |
32 # include "thread_linux.inline.hpp" | |
33 #endif | |
34 #ifdef TARGET_OS_FAMILY_solaris | |
35 # include "thread_solaris.inline.hpp" | |
36 #endif | |
37 #ifdef TARGET_OS_FAMILY_windows | |
38 # include "thread_windows.inline.hpp" | |
39 #endif | |
3960 | 40 #ifdef TARGET_OS_FAMILY_bsd |
41 # include "thread_bsd.inline.hpp" | |
42 #endif | |
0 | 43 |
44 | |
45 JNIHandleBlock* JNIHandles::_global_handles = NULL; | |
46 JNIHandleBlock* JNIHandles::_weak_global_handles = NULL; | |
47 oop JNIHandles::_deleted_handle = NULL; | |
48 | |
49 | |
50 jobject JNIHandles::make_local(oop obj) { | |
51 if (obj == NULL) { | |
52 return NULL; // ignore null handles | |
53 } else { | |
54 Thread* thread = Thread::current(); | |
55 assert(Universe::heap()->is_in_reserved(obj), "sanity check"); | |
56 return thread->active_handles()->allocate_handle(obj); | |
57 } | |
58 } | |
59 | |
60 | |
61 // optimized versions | |
62 | |
63 jobject JNIHandles::make_local(Thread* thread, oop obj) { | |
64 if (obj == NULL) { | |
65 return NULL; // ignore null handles | |
66 } else { | |
67 assert(Universe::heap()->is_in_reserved(obj), "sanity check"); | |
68 return thread->active_handles()->allocate_handle(obj); | |
69 } | |
70 } | |
71 | |
72 | |
73 jobject JNIHandles::make_local(JNIEnv* env, oop obj) { | |
74 if (obj == NULL) { | |
75 return NULL; // ignore null handles | |
76 } else { | |
77 JavaThread* thread = JavaThread::thread_from_jni_environment(env); | |
78 assert(Universe::heap()->is_in_reserved(obj), "sanity check"); | |
79 return thread->active_handles()->allocate_handle(obj); | |
80 } | |
81 } | |
82 | |
83 | |
84 jobject JNIHandles::make_global(Handle obj) { | |
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85 assert(!Universe::heap()->is_gc_active(), "can't extend the root set during GC"); |
0 | 86 jobject res = NULL; |
87 if (!obj.is_null()) { | |
88 // ignore null handles | |
89 MutexLocker ml(JNIGlobalHandle_lock); | |
90 assert(Universe::heap()->is_in_reserved(obj()), "sanity check"); | |
91 res = _global_handles->allocate_handle(obj()); | |
92 } else { | |
93 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); | |
94 } | |
95 | |
96 return res; | |
97 } | |
98 | |
99 | |
100 jobject JNIHandles::make_weak_global(Handle obj) { | |
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101 assert(!Universe::heap()->is_gc_active(), "can't extend the root set during GC"); |
0 | 102 jobject res = NULL; |
103 if (!obj.is_null()) { | |
104 // ignore null handles | |
105 MutexLocker ml(JNIGlobalHandle_lock); | |
106 assert(Universe::heap()->is_in_reserved(obj()), "sanity check"); | |
107 res = _weak_global_handles->allocate_handle(obj()); | |
108 } else { | |
109 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); | |
110 } | |
111 return res; | |
112 } | |
113 | |
114 jmethodID JNIHandles::make_jmethod_id(methodHandle mh) { | |
115 return (jmethodID) make_weak_global(mh); | |
116 } | |
117 | |
118 | |
119 | |
120 void JNIHandles::change_method_associated_with_jmethod_id(jmethodID jmid, methodHandle mh) { | |
121 MutexLocker ml(JNIGlobalHandle_lock); // Is this necessary? | |
122 Handle obj = (Handle)mh; | |
123 oop* jobj = (oop*)jmid; | |
124 *jobj = obj(); | |
125 } | |
126 | |
127 | |
128 void JNIHandles::destroy_global(jobject handle) { | |
129 if (handle != NULL) { | |
130 assert(is_global_handle(handle), "Invalid delete of global JNI handle"); | |
131 *((oop*)handle) = deleted_handle(); // Mark the handle as deleted, allocate will reuse it | |
132 } | |
133 } | |
134 | |
135 | |
136 void JNIHandles::destroy_weak_global(jobject handle) { | |
137 if (handle != NULL) { | |
138 assert(!CheckJNICalls || is_weak_global_handle(handle), "Invalid delete of weak global JNI handle"); | |
139 *((oop*)handle) = deleted_handle(); // Mark the handle as deleted, allocate will reuse it | |
140 } | |
141 } | |
142 | |
143 void JNIHandles::destroy_jmethod_id(jmethodID mid) { | |
144 destroy_weak_global((jobject)mid); | |
145 } | |
146 | |
147 | |
148 void JNIHandles::oops_do(OopClosure* f) { | |
149 f->do_oop(&_deleted_handle); | |
150 _global_handles->oops_do(f); | |
151 } | |
152 | |
153 | |
154 void JNIHandles::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* f) { | |
155 _weak_global_handles->weak_oops_do(is_alive, f); | |
156 } | |
157 | |
158 | |
159 void JNIHandles::initialize() { | |
160 _global_handles = JNIHandleBlock::allocate_block(); | |
161 _weak_global_handles = JNIHandleBlock::allocate_block(); | |
162 EXCEPTION_MARK; | |
163 // We will never reach the CATCH below since Exceptions::_throw will cause | |
164 // the VM to exit if an exception is thrown during initialization | |
1142 | 165 klassOop k = SystemDictionary::Object_klass(); |
0 | 166 _deleted_handle = instanceKlass::cast(k)->allocate_permanent_instance(CATCH); |
167 } | |
168 | |
169 | |
170 bool JNIHandles::is_local_handle(Thread* thread, jobject handle) { | |
171 JNIHandleBlock* block = thread->active_handles(); | |
172 | |
173 // Look back past possible native calls to jni_PushLocalFrame. | |
174 while (block != NULL) { | |
175 if (block->chain_contains(handle)) { | |
176 return true; | |
177 } | |
178 block = block->pop_frame_link(); | |
179 } | |
180 return false; | |
181 } | |
182 | |
183 | |
184 // Determine if the handle is somewhere in the current thread's stack. | |
185 // We easily can't isolate any particular stack frame the handle might | |
186 // come from, so we'll check the whole stack. | |
187 | |
188 bool JNIHandles::is_frame_handle(JavaThread* thr, jobject obj) { | |
189 // If there is no java frame, then this must be top level code, such | |
190 // as the java command executable, in which case, this type of handle | |
191 // is not permitted. | |
192 return (thr->has_last_Java_frame() && | |
193 (void*)obj < (void*)thr->stack_base() && | |
194 (void*)obj >= (void*)thr->last_Java_sp()); | |
195 } | |
196 | |
197 | |
198 bool JNIHandles::is_global_handle(jobject handle) { | |
199 return _global_handles->chain_contains(handle); | |
200 } | |
201 | |
202 | |
203 bool JNIHandles::is_weak_global_handle(jobject handle) { | |
204 return _weak_global_handles->chain_contains(handle); | |
205 } | |
206 | |
207 long JNIHandles::global_handle_memory_usage() { | |
208 return _global_handles->memory_usage(); | |
209 } | |
210 | |
211 long JNIHandles::weak_global_handle_memory_usage() { | |
212 return _weak_global_handles->memory_usage(); | |
213 } | |
214 | |
215 | |
216 class AlwaysAliveClosure: public BoolObjectClosure { | |
217 public: | |
218 bool do_object_b(oop obj) { return true; } | |
219 void do_object(oop obj) { assert(false, "Don't call"); } | |
220 }; | |
221 | |
222 class CountHandleClosure: public OopClosure { | |
223 private: | |
224 int _count; | |
225 public: | |
226 CountHandleClosure(): _count(0) {} | |
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227 virtual void do_oop(oop* unused) { |
0 | 228 _count++; |
229 } | |
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230 virtual void do_oop(narrowOop* unused) { ShouldNotReachHere(); } |
0 | 231 int count() { return _count; } |
232 }; | |
233 | |
234 // We assume this is called at a safepoint: no lock is needed. | |
235 void JNIHandles::print_on(outputStream* st) { | |
236 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); | |
237 assert(_global_handles != NULL && _weak_global_handles != NULL, | |
238 "JNIHandles not initialized"); | |
239 | |
240 CountHandleClosure global_handle_count; | |
241 AlwaysAliveClosure always_alive; | |
242 oops_do(&global_handle_count); | |
243 weak_oops_do(&always_alive, &global_handle_count); | |
244 | |
245 st->print_cr("JNI global references: %d", global_handle_count.count()); | |
246 st->cr(); | |
247 st->flush(); | |
248 } | |
249 | |
250 class VerifyHandleClosure: public OopClosure { | |
251 public: | |
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252 virtual void do_oop(oop* root) { |
0 | 253 (*root)->verify(); |
254 } | |
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255 virtual void do_oop(narrowOop* root) { ShouldNotReachHere(); } |
0 | 256 }; |
257 | |
258 void JNIHandles::verify() { | |
259 VerifyHandleClosure verify_handle; | |
260 AlwaysAliveClosure always_alive; | |
261 | |
262 oops_do(&verify_handle); | |
263 weak_oops_do(&always_alive, &verify_handle); | |
264 } | |
265 | |
266 | |
267 | |
268 void jni_handles_init() { | |
269 JNIHandles::initialize(); | |
270 } | |
271 | |
272 | |
273 int JNIHandleBlock::_blocks_allocated = 0; | |
274 JNIHandleBlock* JNIHandleBlock::_block_free_list = NULL; | |
275 #ifndef PRODUCT | |
276 JNIHandleBlock* JNIHandleBlock::_block_list = NULL; | |
277 #endif | |
278 | |
279 | |
280 void JNIHandleBlock::zap() { | |
281 // Zap block values | |
282 _top = 0; | |
283 for (int index = 0; index < block_size_in_oops; index++) { | |
284 _handles[index] = badJNIHandle; | |
285 } | |
286 } | |
287 | |
288 JNIHandleBlock* JNIHandleBlock::allocate_block(Thread* thread) { | |
289 assert(thread == NULL || thread == Thread::current(), "sanity check"); | |
290 JNIHandleBlock* block; | |
291 // Check the thread-local free list for a block so we don't | |
292 // have to acquire a mutex. | |
293 if (thread != NULL && thread->free_handle_block() != NULL) { | |
294 block = thread->free_handle_block(); | |
295 thread->set_free_handle_block(block->_next); | |
296 } | |
297 else { | |
298 // locking with safepoint checking introduces a potential deadlock: | |
299 // - we would hold JNIHandleBlockFreeList_lock and then Threads_lock | |
300 // - another would hold Threads_lock (jni_AttachCurrentThread) and then | |
301 // JNIHandleBlockFreeList_lock (JNIHandleBlock::allocate_block) | |
302 MutexLockerEx ml(JNIHandleBlockFreeList_lock, | |
303 Mutex::_no_safepoint_check_flag); | |
304 if (_block_free_list == NULL) { | |
305 // Allocate new block | |
306 block = new JNIHandleBlock(); | |
307 _blocks_allocated++; | |
308 if (TraceJNIHandleAllocation) { | |
309 tty->print_cr("JNIHandleBlock " INTPTR_FORMAT " allocated (%d total blocks)", | |
310 block, _blocks_allocated); | |
311 } | |
312 if (ZapJNIHandleArea) block->zap(); | |
313 #ifndef PRODUCT | |
314 // Link new block to list of all allocated blocks | |
315 block->_block_list_link = _block_list; | |
316 _block_list = block; | |
317 #endif | |
318 } else { | |
319 // Get block from free list | |
320 block = _block_free_list; | |
321 _block_free_list = _block_free_list->_next; | |
322 } | |
323 } | |
324 block->_top = 0; | |
325 block->_next = NULL; | |
326 block->_pop_frame_link = NULL; | |
327 // _last, _free_list & _allocate_before_rebuild initialized in allocate_handle | |
328 debug_only(block->_last = NULL); | |
329 debug_only(block->_free_list = NULL); | |
330 debug_only(block->_allocate_before_rebuild = -1); | |
331 return block; | |
332 } | |
333 | |
334 | |
335 void JNIHandleBlock::release_block(JNIHandleBlock* block, Thread* thread) { | |
336 assert(thread == NULL || thread == Thread::current(), "sanity check"); | |
337 JNIHandleBlock* pop_frame_link = block->pop_frame_link(); | |
338 // Put returned block at the beginning of the thread-local free list. | |
339 // Note that if thread == NULL, we use it as an implicit argument that | |
340 // we _don't_ want the block to be kept on the free_handle_block. | |
341 // See for instance JavaThread::exit(). | |
342 if (thread != NULL ) { | |
343 if (ZapJNIHandleArea) block->zap(); | |
344 JNIHandleBlock* freelist = thread->free_handle_block(); | |
345 block->_pop_frame_link = NULL; | |
346 thread->set_free_handle_block(block); | |
347 | |
348 // Add original freelist to end of chain | |
349 if ( freelist != NULL ) { | |
350 while ( block->_next != NULL ) block = block->_next; | |
351 block->_next = freelist; | |
352 } | |
353 block = NULL; | |
354 } | |
355 if (block != NULL) { | |
356 // Return blocks to free list | |
357 // locking with safepoint checking introduces a potential deadlock: | |
358 // - we would hold JNIHandleBlockFreeList_lock and then Threads_lock | |
359 // - another would hold Threads_lock (jni_AttachCurrentThread) and then | |
360 // JNIHandleBlockFreeList_lock (JNIHandleBlock::allocate_block) | |
361 MutexLockerEx ml(JNIHandleBlockFreeList_lock, | |
362 Mutex::_no_safepoint_check_flag); | |
363 while (block != NULL) { | |
364 if (ZapJNIHandleArea) block->zap(); | |
365 JNIHandleBlock* next = block->_next; | |
366 block->_next = _block_free_list; | |
367 _block_free_list = block; | |
368 block = next; | |
369 } | |
370 } | |
371 if (pop_frame_link != NULL) { | |
372 // As a sanity check we release blocks pointed to by the pop_frame_link. | |
373 // This should never happen (only if PopLocalFrame is not called the | |
374 // correct number of times). | |
375 release_block(pop_frame_link, thread); | |
376 } | |
377 } | |
378 | |
379 | |
380 void JNIHandleBlock::oops_do(OopClosure* f) { | |
381 JNIHandleBlock* current_chain = this; | |
382 // Iterate over chain of blocks, followed by chains linked through the | |
383 // pop frame links. | |
384 while (current_chain != NULL) { | |
385 for (JNIHandleBlock* current = current_chain; current != NULL; | |
386 current = current->_next) { | |
387 assert(current == current_chain || current->pop_frame_link() == NULL, | |
388 "only blocks first in chain should have pop frame link set"); | |
389 for (int index = 0; index < current->_top; index++) { | |
390 oop* root = &(current->_handles)[index]; | |
391 oop value = *root; | |
392 // traverse heap pointers only, not deleted handles or free list | |
393 // pointers | |
394 if (value != NULL && Universe::heap()->is_in_reserved(value)) { | |
395 f->do_oop(root); | |
396 } | |
397 } | |
398 // the next handle block is valid only if current block is full | |
399 if (current->_top < block_size_in_oops) { | |
400 break; | |
401 } | |
402 } | |
403 current_chain = current_chain->pop_frame_link(); | |
404 } | |
405 } | |
406 | |
407 | |
408 void JNIHandleBlock::weak_oops_do(BoolObjectClosure* is_alive, | |
409 OopClosure* f) { | |
410 for (JNIHandleBlock* current = this; current != NULL; current = current->_next) { | |
411 assert(current->pop_frame_link() == NULL, | |
412 "blocks holding weak global JNI handles should not have pop frame link set"); | |
413 for (int index = 0; index < current->_top; index++) { | |
414 oop* root = &(current->_handles)[index]; | |
415 oop value = *root; | |
416 // traverse heap pointers only, not deleted handles or free list pointers | |
417 if (value != NULL && Universe::heap()->is_in_reserved(value)) { | |
418 if (is_alive->do_object_b(value)) { | |
419 // The weakly referenced object is alive, update pointer | |
420 f->do_oop(root); | |
421 } else { | |
422 // The weakly referenced object is not alive, clear the reference by storing NULL | |
423 if (TraceReferenceGC) { | |
424 tty->print_cr("Clearing JNI weak reference (" INTPTR_FORMAT ")", root); | |
425 } | |
426 *root = NULL; | |
427 } | |
428 } | |
429 } | |
430 // the next handle block is valid only if current block is full | |
431 if (current->_top < block_size_in_oops) { | |
432 break; | |
433 } | |
434 } | |
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435 |
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436 /* |
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437 * JVMTI data structures may also contain weak oops. The iteration of them |
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438 * is placed here so that we don't need to add it to each of the collectors. |
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439 */ |
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440 JvmtiExport::weak_oops_do(is_alive, f); |
0 | 441 } |
442 | |
443 | |
444 jobject JNIHandleBlock::allocate_handle(oop obj) { | |
445 assert(Universe::heap()->is_in_reserved(obj), "sanity check"); | |
446 if (_top == 0) { | |
447 // This is the first allocation or the initial block got zapped when | |
448 // entering a native function. If we have any following blocks they are | |
449 // not valid anymore. | |
450 for (JNIHandleBlock* current = _next; current != NULL; | |
451 current = current->_next) { | |
452 assert(current->_last == NULL, "only first block should have _last set"); | |
453 assert(current->_free_list == NULL, | |
454 "only first block should have _free_list set"); | |
455 current->_top = 0; | |
456 if (ZapJNIHandleArea) current->zap(); | |
457 } | |
458 // Clear initial block | |
459 _free_list = NULL; | |
460 _allocate_before_rebuild = 0; | |
461 _last = this; | |
462 if (ZapJNIHandleArea) zap(); | |
463 } | |
464 | |
465 // Try last block | |
466 if (_last->_top < block_size_in_oops) { | |
467 oop* handle = &(_last->_handles)[_last->_top++]; | |
468 *handle = obj; | |
469 return (jobject) handle; | |
470 } | |
471 | |
472 // Try free list | |
473 if (_free_list != NULL) { | |
474 oop* handle = _free_list; | |
475 _free_list = (oop*) *_free_list; | |
476 *handle = obj; | |
477 return (jobject) handle; | |
478 } | |
479 // Check if unused block follow last | |
480 if (_last->_next != NULL) { | |
481 // update last and retry | |
482 _last = _last->_next; | |
483 return allocate_handle(obj); | |
484 } | |
485 | |
486 // No space available, we have to rebuild free list or expand | |
487 if (_allocate_before_rebuild == 0) { | |
488 rebuild_free_list(); // updates _allocate_before_rebuild counter | |
489 } else { | |
490 // Append new block | |
491 Thread* thread = Thread::current(); | |
492 Handle obj_handle(thread, obj); | |
493 // This can block, so we need to preserve obj accross call. | |
494 _last->_next = JNIHandleBlock::allocate_block(thread); | |
495 _last = _last->_next; | |
496 _allocate_before_rebuild--; | |
497 obj = obj_handle(); | |
498 } | |
499 return allocate_handle(obj); // retry | |
500 } | |
501 | |
502 | |
503 void JNIHandleBlock::rebuild_free_list() { | |
504 assert(_allocate_before_rebuild == 0 && _free_list == NULL, "just checking"); | |
505 int free = 0; | |
506 int blocks = 0; | |
507 for (JNIHandleBlock* current = this; current != NULL; current = current->_next) { | |
508 for (int index = 0; index < current->_top; index++) { | |
509 oop* handle = &(current->_handles)[index]; | |
510 if (*handle == JNIHandles::deleted_handle()) { | |
511 // this handle was cleared out by a delete call, reuse it | |
512 *handle = (oop) _free_list; | |
513 _free_list = handle; | |
514 free++; | |
515 } | |
516 } | |
517 // we should not rebuild free list if there are unused handles at the end | |
518 assert(current->_top == block_size_in_oops, "just checking"); | |
519 blocks++; | |
520 } | |
521 // Heuristic: if more than half of the handles are free we rebuild next time | |
522 // as well, otherwise we append a corresponding number of new blocks before | |
523 // attempting a free list rebuild again. | |
524 int total = blocks * block_size_in_oops; | |
525 int extra = total - 2*free; | |
526 if (extra > 0) { | |
527 // Not as many free handles as we would like - compute number of new blocks to append | |
528 _allocate_before_rebuild = (extra + block_size_in_oops - 1) / block_size_in_oops; | |
529 } | |
530 if (TraceJNIHandleAllocation) { | |
531 tty->print_cr("Rebuild free list JNIHandleBlock " INTPTR_FORMAT " blocks=%d used=%d free=%d add=%d", | |
532 this, blocks, total-free, free, _allocate_before_rebuild); | |
533 } | |
534 } | |
535 | |
536 | |
537 bool JNIHandleBlock::contains(jobject handle) const { | |
538 return ((jobject)&_handles[0] <= handle && handle<(jobject)&_handles[_top]); | |
539 } | |
540 | |
541 | |
542 bool JNIHandleBlock::chain_contains(jobject handle) const { | |
543 for (JNIHandleBlock* current = (JNIHandleBlock*) this; current != NULL; current = current->_next) { | |
544 if (current->contains(handle)) { | |
545 return true; | |
546 } | |
547 } | |
548 return false; | |
549 } | |
550 | |
551 | |
552 int JNIHandleBlock::length() const { | |
553 int result = 1; | |
554 for (JNIHandleBlock* current = _next; current != NULL; current = current->_next) { | |
555 result++; | |
556 } | |
557 return result; | |
558 } | |
559 | |
560 // This method is not thread-safe, i.e., must be called whule holding a lock on the | |
561 // structure. | |
562 long JNIHandleBlock::memory_usage() const { | |
563 return length() * sizeof(JNIHandleBlock); | |
564 } | |
565 | |
566 | |
567 #ifndef PRODUCT | |
568 | |
569 bool JNIHandleBlock::any_contains(jobject handle) { | |
570 for (JNIHandleBlock* current = _block_list; current != NULL; current = current->_block_list_link) { | |
571 if (current->contains(handle)) { | |
572 return true; | |
573 } | |
574 } | |
575 return false; | |
576 } | |
577 | |
578 void JNIHandleBlock::print_statistics() { | |
579 int used_blocks = 0; | |
580 int free_blocks = 0; | |
581 int used_handles = 0; | |
582 int free_handles = 0; | |
583 JNIHandleBlock* block = _block_list; | |
584 while (block != NULL) { | |
585 if (block->_top > 0) { | |
586 used_blocks++; | |
587 } else { | |
588 free_blocks++; | |
589 } | |
590 used_handles += block->_top; | |
591 free_handles += (block_size_in_oops - block->_top); | |
592 block = block->_block_list_link; | |
593 } | |
594 tty->print_cr("JNIHandleBlocks statistics"); | |
595 tty->print_cr("- blocks allocated: %d", used_blocks + free_blocks); | |
596 tty->print_cr("- blocks in use: %d", used_blocks); | |
597 tty->print_cr("- blocks free: %d", free_blocks); | |
598 tty->print_cr("- handles in use: %d", used_handles); | |
599 tty->print_cr("- handles free: %d", free_handles); | |
600 } | |
601 | |
602 #endif |