author | pliden |
Fri, 11 Apr 2014 12:29:24 +0200 | |
changeset 24094 | 5dbf1f44de18 |
parent 22556 | a17351e8c2c2 |
child 24424 | 2658d7834c6e |
permissions | -rw-r--r-- |
1 | 1 |
/* |
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* Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. |
|
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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* |
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*/ |
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||
7397 | 25 |
#include "precompiled.hpp" |
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#include "classfile/systemDictionary.hpp" |
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#include "oops/oop.inline.hpp" |
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#include "prims/jvmtiExport.hpp" |
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#include "runtime/jniHandles.hpp" |
30 |
#include "runtime/mutexLocker.hpp" |
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#include "runtime/thread.inline.hpp" |
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|
33 |
||
34 |
JNIHandleBlock* JNIHandles::_global_handles = NULL; |
|
35 |
JNIHandleBlock* JNIHandles::_weak_global_handles = NULL; |
|
36 |
oop JNIHandles::_deleted_handle = NULL; |
|
37 |
||
38 |
||
39 |
jobject JNIHandles::make_local(oop obj) { |
|
40 |
if (obj == NULL) { |
|
41 |
return NULL; // ignore null handles |
|
42 |
} else { |
|
43 |
Thread* thread = Thread::current(); |
|
44 |
assert(Universe::heap()->is_in_reserved(obj), "sanity check"); |
|
45 |
return thread->active_handles()->allocate_handle(obj); |
|
46 |
} |
|
47 |
} |
|
48 |
||
49 |
||
50 |
// optimized versions |
|
51 |
||
52 |
jobject JNIHandles::make_local(Thread* thread, oop obj) { |
|
53 |
if (obj == NULL) { |
|
54 |
return NULL; // ignore null handles |
|
55 |
} else { |
|
56 |
assert(Universe::heap()->is_in_reserved(obj), "sanity check"); |
|
57 |
return thread->active_handles()->allocate_handle(obj); |
|
58 |
} |
|
59 |
} |
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60 |
||
61 |
||
62 |
jobject JNIHandles::make_local(JNIEnv* env, oop obj) { |
|
63 |
if (obj == NULL) { |
|
64 |
return NULL; // ignore null handles |
|
65 |
} else { |
|
66 |
JavaThread* thread = JavaThread::thread_from_jni_environment(env); |
|
67 |
assert(Universe::heap()->is_in_reserved(obj), "sanity check"); |
|
68 |
return thread->active_handles()->allocate_handle(obj); |
|
69 |
} |
|
70 |
} |
|
71 |
||
72 |
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73 |
jobject JNIHandles::make_global(Handle obj) { |
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assert(!Universe::heap()->is_gc_active(), "can't extend the root set during GC"); |
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jobject res = NULL; |
76 |
if (!obj.is_null()) { |
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// ignore null handles |
|
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MutexLocker ml(JNIGlobalHandle_lock); |
|
79 |
assert(Universe::heap()->is_in_reserved(obj()), "sanity check"); |
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res = _global_handles->allocate_handle(obj()); |
|
81 |
} else { |
|
82 |
CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); |
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} |
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||
85 |
return res; |
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} |
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||
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||
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jobject JNIHandles::make_weak_global(Handle obj) { |
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assert(!Universe::heap()->is_gc_active(), "can't extend the root set during GC"); |
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jobject res = NULL; |
92 |
if (!obj.is_null()) { |
|
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// ignore null handles |
|
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MutexLocker ml(JNIGlobalHandle_lock); |
|
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assert(Universe::heap()->is_in_reserved(obj()), "sanity check"); |
|
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res = _weak_global_handles->allocate_handle(obj()); |
|
97 |
} else { |
|
98 |
CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops()); |
|
99 |
} |
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return res; |
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101 |
} |
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102 |
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103 |
||
104 |
void JNIHandles::destroy_global(jobject handle) { |
|
105 |
if (handle != NULL) { |
|
106 |
assert(is_global_handle(handle), "Invalid delete of global JNI handle"); |
|
107 |
*((oop*)handle) = deleted_handle(); // Mark the handle as deleted, allocate will reuse it |
|
108 |
} |
|
109 |
} |
|
110 |
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111 |
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112 |
void JNIHandles::destroy_weak_global(jobject handle) { |
|
113 |
if (handle != NULL) { |
|
114 |
assert(!CheckJNICalls || is_weak_global_handle(handle), "Invalid delete of weak global JNI handle"); |
|
115 |
*((oop*)handle) = deleted_handle(); // Mark the handle as deleted, allocate will reuse it |
|
116 |
} |
|
117 |
} |
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118 |
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119 |
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120 |
void JNIHandles::oops_do(OopClosure* f) { |
|
121 |
f->do_oop(&_deleted_handle); |
|
122 |
_global_handles->oops_do(f); |
|
123 |
} |
|
124 |
||
125 |
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126 |
void JNIHandles::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* f) { |
|
127 |
_weak_global_handles->weak_oops_do(is_alive, f); |
|
128 |
} |
|
129 |
||
130 |
||
131 |
void JNIHandles::initialize() { |
|
132 |
_global_handles = JNIHandleBlock::allocate_block(); |
|
133 |
_weak_global_handles = JNIHandleBlock::allocate_block(); |
|
134 |
EXCEPTION_MARK; |
|
135 |
// We will never reach the CATCH below since Exceptions::_throw will cause |
|
136 |
// the VM to exit if an exception is thrown during initialization |
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Klass* k = SystemDictionary::Object_klass(); |
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_deleted_handle = InstanceKlass::cast(k)->allocate_instance(CATCH); |
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} |
140 |
||
141 |
||
142 |
bool JNIHandles::is_local_handle(Thread* thread, jobject handle) { |
|
143 |
JNIHandleBlock* block = thread->active_handles(); |
|
144 |
||
145 |
// Look back past possible native calls to jni_PushLocalFrame. |
|
146 |
while (block != NULL) { |
|
147 |
if (block->chain_contains(handle)) { |
|
148 |
return true; |
|
149 |
} |
|
150 |
block = block->pop_frame_link(); |
|
151 |
} |
|
152 |
return false; |
|
153 |
} |
|
154 |
||
155 |
||
156 |
// Determine if the handle is somewhere in the current thread's stack. |
|
157 |
// We easily can't isolate any particular stack frame the handle might |
|
158 |
// come from, so we'll check the whole stack. |
|
159 |
||
160 |
bool JNIHandles::is_frame_handle(JavaThread* thr, jobject obj) { |
|
161 |
// If there is no java frame, then this must be top level code, such |
|
162 |
// as the java command executable, in which case, this type of handle |
|
163 |
// is not permitted. |
|
164 |
return (thr->has_last_Java_frame() && |
|
165 |
(void*)obj < (void*)thr->stack_base() && |
|
166 |
(void*)obj >= (void*)thr->last_Java_sp()); |
|
167 |
} |
|
168 |
||
169 |
||
170 |
bool JNIHandles::is_global_handle(jobject handle) { |
|
171 |
return _global_handles->chain_contains(handle); |
|
172 |
} |
|
173 |
||
174 |
||
175 |
bool JNIHandles::is_weak_global_handle(jobject handle) { |
|
176 |
return _weak_global_handles->chain_contains(handle); |
|
177 |
} |
|
178 |
||
179 |
long JNIHandles::global_handle_memory_usage() { |
|
180 |
return _global_handles->memory_usage(); |
|
181 |
} |
|
182 |
||
183 |
long JNIHandles::weak_global_handle_memory_usage() { |
|
184 |
return _weak_global_handles->memory_usage(); |
|
185 |
} |
|
186 |
||
187 |
||
188 |
class AlwaysAliveClosure: public BoolObjectClosure { |
|
189 |
public: |
|
190 |
bool do_object_b(oop obj) { return true; } |
|
191 |
}; |
|
192 |
||
193 |
class CountHandleClosure: public OopClosure { |
|
194 |
private: |
|
195 |
int _count; |
|
196 |
public: |
|
197 |
CountHandleClosure(): _count(0) {} |
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virtual void do_oop(oop* ooph) { |
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if (*ooph != JNIHandles::deleted_handle()) { |
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_count++; |
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} |
1 | 202 |
} |
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virtual void do_oop(narrowOop* unused) { ShouldNotReachHere(); } |
1 | 204 |
int count() { return _count; } |
205 |
}; |
|
206 |
||
207 |
// We assume this is called at a safepoint: no lock is needed. |
|
208 |
void JNIHandles::print_on(outputStream* st) { |
|
209 |
assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); |
|
210 |
assert(_global_handles != NULL && _weak_global_handles != NULL, |
|
211 |
"JNIHandles not initialized"); |
|
212 |
||
213 |
CountHandleClosure global_handle_count; |
|
214 |
AlwaysAliveClosure always_alive; |
|
215 |
oops_do(&global_handle_count); |
|
216 |
weak_oops_do(&always_alive, &global_handle_count); |
|
217 |
||
218 |
st->print_cr("JNI global references: %d", global_handle_count.count()); |
|
219 |
st->cr(); |
|
220 |
st->flush(); |
|
221 |
} |
|
222 |
||
223 |
class VerifyHandleClosure: public OopClosure { |
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224 |
public: |
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virtual void do_oop(oop* root) { |
1 | 226 |
(*root)->verify(); |
227 |
} |
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virtual void do_oop(narrowOop* root) { ShouldNotReachHere(); } |
1 | 229 |
}; |
230 |
||
231 |
void JNIHandles::verify() { |
|
232 |
VerifyHandleClosure verify_handle; |
|
233 |
AlwaysAliveClosure always_alive; |
|
234 |
||
235 |
oops_do(&verify_handle); |
|
236 |
weak_oops_do(&always_alive, &verify_handle); |
|
237 |
} |
|
238 |
||
239 |
||
240 |
||
241 |
void jni_handles_init() { |
|
242 |
JNIHandles::initialize(); |
|
243 |
} |
|
244 |
||
245 |
||
246 |
int JNIHandleBlock::_blocks_allocated = 0; |
|
247 |
JNIHandleBlock* JNIHandleBlock::_block_free_list = NULL; |
|
248 |
#ifndef PRODUCT |
|
249 |
JNIHandleBlock* JNIHandleBlock::_block_list = NULL; |
|
250 |
#endif |
|
251 |
||
252 |
||
253 |
void JNIHandleBlock::zap() { |
|
254 |
// Zap block values |
|
255 |
_top = 0; |
|
256 |
for (int index = 0; index < block_size_in_oops; index++) { |
|
257 |
_handles[index] = badJNIHandle; |
|
258 |
} |
|
259 |
} |
|
260 |
||
261 |
JNIHandleBlock* JNIHandleBlock::allocate_block(Thread* thread) { |
|
262 |
assert(thread == NULL || thread == Thread::current(), "sanity check"); |
|
263 |
JNIHandleBlock* block; |
|
264 |
// Check the thread-local free list for a block so we don't |
|
265 |
// have to acquire a mutex. |
|
266 |
if (thread != NULL && thread->free_handle_block() != NULL) { |
|
267 |
block = thread->free_handle_block(); |
|
268 |
thread->set_free_handle_block(block->_next); |
|
269 |
} |
|
270 |
else { |
|
271 |
// locking with safepoint checking introduces a potential deadlock: |
|
272 |
// - we would hold JNIHandleBlockFreeList_lock and then Threads_lock |
|
273 |
// - another would hold Threads_lock (jni_AttachCurrentThread) and then |
|
274 |
// JNIHandleBlockFreeList_lock (JNIHandleBlock::allocate_block) |
|
275 |
MutexLockerEx ml(JNIHandleBlockFreeList_lock, |
|
276 |
Mutex::_no_safepoint_check_flag); |
|
277 |
if (_block_free_list == NULL) { |
|
278 |
// Allocate new block |
|
279 |
block = new JNIHandleBlock(); |
|
280 |
_blocks_allocated++; |
|
281 |
if (TraceJNIHandleAllocation) { |
|
282 |
tty->print_cr("JNIHandleBlock " INTPTR_FORMAT " allocated (%d total blocks)", |
|
283 |
block, _blocks_allocated); |
|
284 |
} |
|
285 |
if (ZapJNIHandleArea) block->zap(); |
|
286 |
#ifndef PRODUCT |
|
287 |
// Link new block to list of all allocated blocks |
|
288 |
block->_block_list_link = _block_list; |
|
289 |
_block_list = block; |
|
290 |
#endif |
|
291 |
} else { |
|
292 |
// Get block from free list |
|
293 |
block = _block_free_list; |
|
294 |
_block_free_list = _block_free_list->_next; |
|
295 |
} |
|
296 |
} |
|
297 |
block->_top = 0; |
|
298 |
block->_next = NULL; |
|
299 |
block->_pop_frame_link = NULL; |
|
300 |
// _last, _free_list & _allocate_before_rebuild initialized in allocate_handle |
|
301 |
debug_only(block->_last = NULL); |
|
302 |
debug_only(block->_free_list = NULL); |
|
303 |
debug_only(block->_allocate_before_rebuild = -1); |
|
304 |
return block; |
|
305 |
} |
|
306 |
||
307 |
||
308 |
void JNIHandleBlock::release_block(JNIHandleBlock* block, Thread* thread) { |
|
309 |
assert(thread == NULL || thread == Thread::current(), "sanity check"); |
|
310 |
JNIHandleBlock* pop_frame_link = block->pop_frame_link(); |
|
311 |
// Put returned block at the beginning of the thread-local free list. |
|
312 |
// Note that if thread == NULL, we use it as an implicit argument that |
|
313 |
// we _don't_ want the block to be kept on the free_handle_block. |
|
314 |
// See for instance JavaThread::exit(). |
|
315 |
if (thread != NULL ) { |
|
316 |
if (ZapJNIHandleArea) block->zap(); |
|
317 |
JNIHandleBlock* freelist = thread->free_handle_block(); |
|
318 |
block->_pop_frame_link = NULL; |
|
319 |
thread->set_free_handle_block(block); |
|
320 |
||
321 |
// Add original freelist to end of chain |
|
322 |
if ( freelist != NULL ) { |
|
323 |
while ( block->_next != NULL ) block = block->_next; |
|
324 |
block->_next = freelist; |
|
325 |
} |
|
326 |
block = NULL; |
|
327 |
} |
|
328 |
if (block != NULL) { |
|
329 |
// Return blocks to free list |
|
330 |
// locking with safepoint checking introduces a potential deadlock: |
|
331 |
// - we would hold JNIHandleBlockFreeList_lock and then Threads_lock |
|
332 |
// - another would hold Threads_lock (jni_AttachCurrentThread) and then |
|
333 |
// JNIHandleBlockFreeList_lock (JNIHandleBlock::allocate_block) |
|
334 |
MutexLockerEx ml(JNIHandleBlockFreeList_lock, |
|
335 |
Mutex::_no_safepoint_check_flag); |
|
336 |
while (block != NULL) { |
|
337 |
if (ZapJNIHandleArea) block->zap(); |
|
338 |
JNIHandleBlock* next = block->_next; |
|
339 |
block->_next = _block_free_list; |
|
340 |
_block_free_list = block; |
|
341 |
block = next; |
|
342 |
} |
|
343 |
} |
|
344 |
if (pop_frame_link != NULL) { |
|
345 |
// As a sanity check we release blocks pointed to by the pop_frame_link. |
|
346 |
// This should never happen (only if PopLocalFrame is not called the |
|
347 |
// correct number of times). |
|
348 |
release_block(pop_frame_link, thread); |
|
349 |
} |
|
350 |
} |
|
351 |
||
352 |
||
353 |
void JNIHandleBlock::oops_do(OopClosure* f) { |
|
354 |
JNIHandleBlock* current_chain = this; |
|
355 |
// Iterate over chain of blocks, followed by chains linked through the |
|
356 |
// pop frame links. |
|
357 |
while (current_chain != NULL) { |
|
358 |
for (JNIHandleBlock* current = current_chain; current != NULL; |
|
359 |
current = current->_next) { |
|
360 |
assert(current == current_chain || current->pop_frame_link() == NULL, |
|
361 |
"only blocks first in chain should have pop frame link set"); |
|
362 |
for (int index = 0; index < current->_top; index++) { |
|
363 |
oop* root = &(current->_handles)[index]; |
|
364 |
oop value = *root; |
|
365 |
// traverse heap pointers only, not deleted handles or free list |
|
366 |
// pointers |
|
367 |
if (value != NULL && Universe::heap()->is_in_reserved(value)) { |
|
368 |
f->do_oop(root); |
|
369 |
} |
|
370 |
} |
|
371 |
// the next handle block is valid only if current block is full |
|
372 |
if (current->_top < block_size_in_oops) { |
|
373 |
break; |
|
374 |
} |
|
375 |
} |
|
376 |
current_chain = current_chain->pop_frame_link(); |
|
377 |
} |
|
378 |
} |
|
379 |
||
380 |
||
381 |
void JNIHandleBlock::weak_oops_do(BoolObjectClosure* is_alive, |
|
382 |
OopClosure* f) { |
|
383 |
for (JNIHandleBlock* current = this; current != NULL; current = current->_next) { |
|
384 |
assert(current->pop_frame_link() == NULL, |
|
385 |
"blocks holding weak global JNI handles should not have pop frame link set"); |
|
386 |
for (int index = 0; index < current->_top; index++) { |
|
387 |
oop* root = &(current->_handles)[index]; |
|
388 |
oop value = *root; |
|
389 |
// traverse heap pointers only, not deleted handles or free list pointers |
|
390 |
if (value != NULL && Universe::heap()->is_in_reserved(value)) { |
|
391 |
if (is_alive->do_object_b(value)) { |
|
392 |
// The weakly referenced object is alive, update pointer |
|
393 |
f->do_oop(root); |
|
394 |
} else { |
|
395 |
// The weakly referenced object is not alive, clear the reference by storing NULL |
|
396 |
if (TraceReferenceGC) { |
|
397 |
tty->print_cr("Clearing JNI weak reference (" INTPTR_FORMAT ")", root); |
|
398 |
} |
|
399 |
*root = NULL; |
|
400 |
} |
|
401 |
} |
|
402 |
} |
|
403 |
// the next handle block is valid only if current block is full |
|
404 |
if (current->_top < block_size_in_oops) { |
|
405 |
break; |
|
406 |
} |
|
407 |
} |
|
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changeset
|
408 |
|
08aadd7aa3ee
6458402: 3 jvmti tests fail with CMS and +ExplicitGCInvokesConcurrent
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|
409 |
/* |
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|
410 |
* JVMTI data structures may also contain weak oops. The iteration of them |
ce1e4ae77aea
7012505: BreakpointWithFullGC.sh fails with Internal Error (src/share/vm/oops/methodOop.cpp:220)
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|
411 |
* is placed here so that we don't need to add it to each of the collectors. |
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|
412 |
*/ |
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|
413 |
JvmtiExport::weak_oops_do(is_alive, f); |
1 | 414 |
} |
415 |
||
416 |
||
417 |
jobject JNIHandleBlock::allocate_handle(oop obj) { |
|
418 |
assert(Universe::heap()->is_in_reserved(obj), "sanity check"); |
|
419 |
if (_top == 0) { |
|
420 |
// This is the first allocation or the initial block got zapped when |
|
421 |
// entering a native function. If we have any following blocks they are |
|
422 |
// not valid anymore. |
|
423 |
for (JNIHandleBlock* current = _next; current != NULL; |
|
424 |
current = current->_next) { |
|
425 |
assert(current->_last == NULL, "only first block should have _last set"); |
|
426 |
assert(current->_free_list == NULL, |
|
427 |
"only first block should have _free_list set"); |
|
428 |
current->_top = 0; |
|
429 |
if (ZapJNIHandleArea) current->zap(); |
|
430 |
} |
|
431 |
// Clear initial block |
|
432 |
_free_list = NULL; |
|
433 |
_allocate_before_rebuild = 0; |
|
434 |
_last = this; |
|
435 |
if (ZapJNIHandleArea) zap(); |
|
436 |
} |
|
437 |
||
438 |
// Try last block |
|
439 |
if (_last->_top < block_size_in_oops) { |
|
440 |
oop* handle = &(_last->_handles)[_last->_top++]; |
|
441 |
*handle = obj; |
|
442 |
return (jobject) handle; |
|
443 |
} |
|
444 |
||
445 |
// Try free list |
|
446 |
if (_free_list != NULL) { |
|
447 |
oop* handle = _free_list; |
|
448 |
_free_list = (oop*) *_free_list; |
|
449 |
*handle = obj; |
|
450 |
return (jobject) handle; |
|
451 |
} |
|
452 |
// Check if unused block follow last |
|
453 |
if (_last->_next != NULL) { |
|
454 |
// update last and retry |
|
455 |
_last = _last->_next; |
|
456 |
return allocate_handle(obj); |
|
457 |
} |
|
458 |
||
459 |
// No space available, we have to rebuild free list or expand |
|
460 |
if (_allocate_before_rebuild == 0) { |
|
461 |
rebuild_free_list(); // updates _allocate_before_rebuild counter |
|
462 |
} else { |
|
463 |
// Append new block |
|
464 |
Thread* thread = Thread::current(); |
|
465 |
Handle obj_handle(thread, obj); |
|
22551 | 466 |
// This can block, so we need to preserve obj across call. |
1 | 467 |
_last->_next = JNIHandleBlock::allocate_block(thread); |
468 |
_last = _last->_next; |
|
469 |
_allocate_before_rebuild--; |
|
470 |
obj = obj_handle(); |
|
471 |
} |
|
472 |
return allocate_handle(obj); // retry |
|
473 |
} |
|
474 |
||
475 |
||
476 |
void JNIHandleBlock::rebuild_free_list() { |
|
477 |
assert(_allocate_before_rebuild == 0 && _free_list == NULL, "just checking"); |
|
478 |
int free = 0; |
|
479 |
int blocks = 0; |
|
480 |
for (JNIHandleBlock* current = this; current != NULL; current = current->_next) { |
|
481 |
for (int index = 0; index < current->_top; index++) { |
|
482 |
oop* handle = &(current->_handles)[index]; |
|
483 |
if (*handle == JNIHandles::deleted_handle()) { |
|
484 |
// this handle was cleared out by a delete call, reuse it |
|
485 |
*handle = (oop) _free_list; |
|
486 |
_free_list = handle; |
|
487 |
free++; |
|
488 |
} |
|
489 |
} |
|
490 |
// we should not rebuild free list if there are unused handles at the end |
|
491 |
assert(current->_top == block_size_in_oops, "just checking"); |
|
492 |
blocks++; |
|
493 |
} |
|
494 |
// Heuristic: if more than half of the handles are free we rebuild next time |
|
495 |
// as well, otherwise we append a corresponding number of new blocks before |
|
496 |
// attempting a free list rebuild again. |
|
497 |
int total = blocks * block_size_in_oops; |
|
498 |
int extra = total - 2*free; |
|
499 |
if (extra > 0) { |
|
500 |
// Not as many free handles as we would like - compute number of new blocks to append |
|
501 |
_allocate_before_rebuild = (extra + block_size_in_oops - 1) / block_size_in_oops; |
|
502 |
} |
|
503 |
if (TraceJNIHandleAllocation) { |
|
504 |
tty->print_cr("Rebuild free list JNIHandleBlock " INTPTR_FORMAT " blocks=%d used=%d free=%d add=%d", |
|
505 |
this, blocks, total-free, free, _allocate_before_rebuild); |
|
506 |
} |
|
507 |
} |
|
508 |
||
509 |
||
510 |
bool JNIHandleBlock::contains(jobject handle) const { |
|
511 |
return ((jobject)&_handles[0] <= handle && handle<(jobject)&_handles[_top]); |
|
512 |
} |
|
513 |
||
514 |
||
515 |
bool JNIHandleBlock::chain_contains(jobject handle) const { |
|
516 |
for (JNIHandleBlock* current = (JNIHandleBlock*) this; current != NULL; current = current->_next) { |
|
517 |
if (current->contains(handle)) { |
|
518 |
return true; |
|
519 |
} |
|
520 |
} |
|
521 |
return false; |
|
522 |
} |
|
523 |
||
524 |
||
525 |
int JNIHandleBlock::length() const { |
|
526 |
int result = 1; |
|
527 |
for (JNIHandleBlock* current = _next; current != NULL; current = current->_next) { |
|
528 |
result++; |
|
529 |
} |
|
530 |
return result; |
|
531 |
} |
|
532 |
||
22551 | 533 |
// This method is not thread-safe, i.e., must be called while holding a lock on the |
1 | 534 |
// structure. |
535 |
long JNIHandleBlock::memory_usage() const { |
|
536 |
return length() * sizeof(JNIHandleBlock); |
|
537 |
} |
|
538 |
||
539 |
||
540 |
#ifndef PRODUCT |
|
541 |
||
542 |
bool JNIHandleBlock::any_contains(jobject handle) { |
|
543 |
for (JNIHandleBlock* current = _block_list; current != NULL; current = current->_block_list_link) { |
|
544 |
if (current->contains(handle)) { |
|
545 |
return true; |
|
546 |
} |
|
547 |
} |
|
548 |
return false; |
|
549 |
} |
|
550 |
||
551 |
void JNIHandleBlock::print_statistics() { |
|
552 |
int used_blocks = 0; |
|
553 |
int free_blocks = 0; |
|
554 |
int used_handles = 0; |
|
555 |
int free_handles = 0; |
|
556 |
JNIHandleBlock* block = _block_list; |
|
557 |
while (block != NULL) { |
|
558 |
if (block->_top > 0) { |
|
559 |
used_blocks++; |
|
560 |
} else { |
|
561 |
free_blocks++; |
|
562 |
} |
|
563 |
used_handles += block->_top; |
|
564 |
free_handles += (block_size_in_oops - block->_top); |
|
565 |
block = block->_block_list_link; |
|
566 |
} |
|
567 |
tty->print_cr("JNIHandleBlocks statistics"); |
|
568 |
tty->print_cr("- blocks allocated: %d", used_blocks + free_blocks); |
|
569 |
tty->print_cr("- blocks in use: %d", used_blocks); |
|
570 |
tty->print_cr("- blocks free: %d", free_blocks); |
|
571 |
tty->print_cr("- handles in use: %d", used_handles); |
|
572 |
tty->print_cr("- handles free: %d", free_handles); |
|
573 |
} |
|
574 |
||
575 |
#endif |