Mercurial > hg > truffle
annotate src/share/vm/runtime/jniHandles.cpp @ 6917:e81fbc04a942
7191817: -XX:+UseSerialGC -XX:+UseLargePages crashes with SIGFPE on MacOS X
Summary: Disable -XX:+UseLargePages for MacOS X
Reviewed-by: dholmes, coleenp, sla
Contributed-by: harold.seigel@oracle.com
author | coleenp |
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date | Thu, 25 Oct 2012 16:33:40 -0400 |
parents | da91efe96a93 |
children | f34d701e952e |
rev | line source |
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0 | 1 /* |
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2 * Copyright (c) 1998, 2012, 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 | |
115 void JNIHandles::destroy_global(jobject handle) { | |
116 if (handle != NULL) { | |
117 assert(is_global_handle(handle), "Invalid delete of global JNI handle"); | |
118 *((oop*)handle) = deleted_handle(); // Mark the handle as deleted, allocate will reuse it | |
119 } | |
120 } | |
121 | |
122 | |
123 void JNIHandles::destroy_weak_global(jobject handle) { | |
124 if (handle != NULL) { | |
125 assert(!CheckJNICalls || is_weak_global_handle(handle), "Invalid delete of weak global JNI handle"); | |
126 *((oop*)handle) = deleted_handle(); // Mark the handle as deleted, allocate will reuse it | |
127 } | |
128 } | |
129 | |
130 | |
131 void JNIHandles::oops_do(OopClosure* f) { | |
132 f->do_oop(&_deleted_handle); | |
133 _global_handles->oops_do(f); | |
134 } | |
135 | |
136 | |
137 void JNIHandles::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* f) { | |
138 _weak_global_handles->weak_oops_do(is_alive, f); | |
139 } | |
140 | |
141 | |
142 void JNIHandles::initialize() { | |
143 _global_handles = JNIHandleBlock::allocate_block(); | |
144 _weak_global_handles = JNIHandleBlock::allocate_block(); | |
145 EXCEPTION_MARK; | |
146 // We will never reach the CATCH below since Exceptions::_throw will cause | |
147 // the VM to exit if an exception is thrown during initialization | |
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148 Klass* k = SystemDictionary::Object_klass(); |
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149 _deleted_handle = InstanceKlass::cast(k)->allocate_instance(CATCH); |
0 | 150 } |
151 | |
152 | |
153 bool JNIHandles::is_local_handle(Thread* thread, jobject handle) { | |
154 JNIHandleBlock* block = thread->active_handles(); | |
155 | |
156 // Look back past possible native calls to jni_PushLocalFrame. | |
157 while (block != NULL) { | |
158 if (block->chain_contains(handle)) { | |
159 return true; | |
160 } | |
161 block = block->pop_frame_link(); | |
162 } | |
163 return false; | |
164 } | |
165 | |
166 | |
167 // Determine if the handle is somewhere in the current thread's stack. | |
168 // We easily can't isolate any particular stack frame the handle might | |
169 // come from, so we'll check the whole stack. | |
170 | |
171 bool JNIHandles::is_frame_handle(JavaThread* thr, jobject obj) { | |
172 // If there is no java frame, then this must be top level code, such | |
173 // as the java command executable, in which case, this type of handle | |
174 // is not permitted. | |
175 return (thr->has_last_Java_frame() && | |
176 (void*)obj < (void*)thr->stack_base() && | |
177 (void*)obj >= (void*)thr->last_Java_sp()); | |
178 } | |
179 | |
180 | |
181 bool JNIHandles::is_global_handle(jobject handle) { | |
182 return _global_handles->chain_contains(handle); | |
183 } | |
184 | |
185 | |
186 bool JNIHandles::is_weak_global_handle(jobject handle) { | |
187 return _weak_global_handles->chain_contains(handle); | |
188 } | |
189 | |
190 long JNIHandles::global_handle_memory_usage() { | |
191 return _global_handles->memory_usage(); | |
192 } | |
193 | |
194 long JNIHandles::weak_global_handle_memory_usage() { | |
195 return _weak_global_handles->memory_usage(); | |
196 } | |
197 | |
198 | |
199 class AlwaysAliveClosure: public BoolObjectClosure { | |
200 public: | |
201 bool do_object_b(oop obj) { return true; } | |
202 void do_object(oop obj) { assert(false, "Don't call"); } | |
203 }; | |
204 | |
205 class CountHandleClosure: public OopClosure { | |
206 private: | |
207 int _count; | |
208 public: | |
209 CountHandleClosure(): _count(0) {} | |
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210 virtual void do_oop(oop* unused) { |
0 | 211 _count++; |
212 } | |
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213 virtual void do_oop(narrowOop* unused) { ShouldNotReachHere(); } |
0 | 214 int count() { return _count; } |
215 }; | |
216 | |
217 // We assume this is called at a safepoint: no lock is needed. | |
218 void JNIHandles::print_on(outputStream* st) { | |
219 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); | |
220 assert(_global_handles != NULL && _weak_global_handles != NULL, | |
221 "JNIHandles not initialized"); | |
222 | |
223 CountHandleClosure global_handle_count; | |
224 AlwaysAliveClosure always_alive; | |
225 oops_do(&global_handle_count); | |
226 weak_oops_do(&always_alive, &global_handle_count); | |
227 | |
228 st->print_cr("JNI global references: %d", global_handle_count.count()); | |
229 st->cr(); | |
230 st->flush(); | |
231 } | |
232 | |
233 class VerifyHandleClosure: public OopClosure { | |
234 public: | |
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235 virtual void do_oop(oop* root) { |
0 | 236 (*root)->verify(); |
237 } | |
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238 virtual void do_oop(narrowOop* root) { ShouldNotReachHere(); } |
0 | 239 }; |
240 | |
241 void JNIHandles::verify() { | |
242 VerifyHandleClosure verify_handle; | |
243 AlwaysAliveClosure always_alive; | |
244 | |
245 oops_do(&verify_handle); | |
246 weak_oops_do(&always_alive, &verify_handle); | |
247 } | |
248 | |
249 | |
250 | |
251 void jni_handles_init() { | |
252 JNIHandles::initialize(); | |
253 } | |
254 | |
255 | |
256 int JNIHandleBlock::_blocks_allocated = 0; | |
257 JNIHandleBlock* JNIHandleBlock::_block_free_list = NULL; | |
258 #ifndef PRODUCT | |
259 JNIHandleBlock* JNIHandleBlock::_block_list = NULL; | |
260 #endif | |
261 | |
262 | |
263 void JNIHandleBlock::zap() { | |
264 // Zap block values | |
265 _top = 0; | |
266 for (int index = 0; index < block_size_in_oops; index++) { | |
267 _handles[index] = badJNIHandle; | |
268 } | |
269 } | |
270 | |
271 JNIHandleBlock* JNIHandleBlock::allocate_block(Thread* thread) { | |
272 assert(thread == NULL || thread == Thread::current(), "sanity check"); | |
273 JNIHandleBlock* block; | |
274 // Check the thread-local free list for a block so we don't | |
275 // have to acquire a mutex. | |
276 if (thread != NULL && thread->free_handle_block() != NULL) { | |
277 block = thread->free_handle_block(); | |
278 thread->set_free_handle_block(block->_next); | |
279 } | |
280 else { | |
281 // locking with safepoint checking introduces a potential deadlock: | |
282 // - we would hold JNIHandleBlockFreeList_lock and then Threads_lock | |
283 // - another would hold Threads_lock (jni_AttachCurrentThread) and then | |
284 // JNIHandleBlockFreeList_lock (JNIHandleBlock::allocate_block) | |
285 MutexLockerEx ml(JNIHandleBlockFreeList_lock, | |
286 Mutex::_no_safepoint_check_flag); | |
287 if (_block_free_list == NULL) { | |
288 // Allocate new block | |
289 block = new JNIHandleBlock(); | |
290 _blocks_allocated++; | |
291 if (TraceJNIHandleAllocation) { | |
292 tty->print_cr("JNIHandleBlock " INTPTR_FORMAT " allocated (%d total blocks)", | |
293 block, _blocks_allocated); | |
294 } | |
295 if (ZapJNIHandleArea) block->zap(); | |
296 #ifndef PRODUCT | |
297 // Link new block to list of all allocated blocks | |
298 block->_block_list_link = _block_list; | |
299 _block_list = block; | |
300 #endif | |
301 } else { | |
302 // Get block from free list | |
303 block = _block_free_list; | |
304 _block_free_list = _block_free_list->_next; | |
305 } | |
306 } | |
307 block->_top = 0; | |
308 block->_next = NULL; | |
309 block->_pop_frame_link = NULL; | |
310 // _last, _free_list & _allocate_before_rebuild initialized in allocate_handle | |
311 debug_only(block->_last = NULL); | |
312 debug_only(block->_free_list = NULL); | |
313 debug_only(block->_allocate_before_rebuild = -1); | |
314 return block; | |
315 } | |
316 | |
317 | |
318 void JNIHandleBlock::release_block(JNIHandleBlock* block, Thread* thread) { | |
319 assert(thread == NULL || thread == Thread::current(), "sanity check"); | |
320 JNIHandleBlock* pop_frame_link = block->pop_frame_link(); | |
321 // Put returned block at the beginning of the thread-local free list. | |
322 // Note that if thread == NULL, we use it as an implicit argument that | |
323 // we _don't_ want the block to be kept on the free_handle_block. | |
324 // See for instance JavaThread::exit(). | |
325 if (thread != NULL ) { | |
326 if (ZapJNIHandleArea) block->zap(); | |
327 JNIHandleBlock* freelist = thread->free_handle_block(); | |
328 block->_pop_frame_link = NULL; | |
329 thread->set_free_handle_block(block); | |
330 | |
331 // Add original freelist to end of chain | |
332 if ( freelist != NULL ) { | |
333 while ( block->_next != NULL ) block = block->_next; | |
334 block->_next = freelist; | |
335 } | |
336 block = NULL; | |
337 } | |
338 if (block != NULL) { | |
339 // Return blocks to free list | |
340 // locking with safepoint checking introduces a potential deadlock: | |
341 // - we would hold JNIHandleBlockFreeList_lock and then Threads_lock | |
342 // - another would hold Threads_lock (jni_AttachCurrentThread) and then | |
343 // JNIHandleBlockFreeList_lock (JNIHandleBlock::allocate_block) | |
344 MutexLockerEx ml(JNIHandleBlockFreeList_lock, | |
345 Mutex::_no_safepoint_check_flag); | |
346 while (block != NULL) { | |
347 if (ZapJNIHandleArea) block->zap(); | |
348 JNIHandleBlock* next = block->_next; | |
349 block->_next = _block_free_list; | |
350 _block_free_list = block; | |
351 block = next; | |
352 } | |
353 } | |
354 if (pop_frame_link != NULL) { | |
355 // As a sanity check we release blocks pointed to by the pop_frame_link. | |
356 // This should never happen (only if PopLocalFrame is not called the | |
357 // correct number of times). | |
358 release_block(pop_frame_link, thread); | |
359 } | |
360 } | |
361 | |
362 | |
363 void JNIHandleBlock::oops_do(OopClosure* f) { | |
364 JNIHandleBlock* current_chain = this; | |
365 // Iterate over chain of blocks, followed by chains linked through the | |
366 // pop frame links. | |
367 while (current_chain != NULL) { | |
368 for (JNIHandleBlock* current = current_chain; current != NULL; | |
369 current = current->_next) { | |
370 assert(current == current_chain || current->pop_frame_link() == NULL, | |
371 "only blocks first in chain should have pop frame link set"); | |
372 for (int index = 0; index < current->_top; index++) { | |
373 oop* root = &(current->_handles)[index]; | |
374 oop value = *root; | |
375 // traverse heap pointers only, not deleted handles or free list | |
376 // pointers | |
377 if (value != NULL && Universe::heap()->is_in_reserved(value)) { | |
378 f->do_oop(root); | |
379 } | |
380 } | |
381 // the next handle block is valid only if current block is full | |
382 if (current->_top < block_size_in_oops) { | |
383 break; | |
384 } | |
385 } | |
386 current_chain = current_chain->pop_frame_link(); | |
387 } | |
388 } | |
389 | |
390 | |
391 void JNIHandleBlock::weak_oops_do(BoolObjectClosure* is_alive, | |
392 OopClosure* f) { | |
393 for (JNIHandleBlock* current = this; current != NULL; current = current->_next) { | |
394 assert(current->pop_frame_link() == NULL, | |
395 "blocks holding weak global JNI handles should not have pop frame link set"); | |
396 for (int index = 0; index < current->_top; index++) { | |
397 oop* root = &(current->_handles)[index]; | |
398 oop value = *root; | |
399 // traverse heap pointers only, not deleted handles or free list pointers | |
400 if (value != NULL && Universe::heap()->is_in_reserved(value)) { | |
401 if (is_alive->do_object_b(value)) { | |
402 // The weakly referenced object is alive, update pointer | |
403 f->do_oop(root); | |
404 } else { | |
405 // The weakly referenced object is not alive, clear the reference by storing NULL | |
406 if (TraceReferenceGC) { | |
407 tty->print_cr("Clearing JNI weak reference (" INTPTR_FORMAT ")", root); | |
408 } | |
409 *root = NULL; | |
410 } | |
411 } | |
412 } | |
413 // the next handle block is valid only if current block is full | |
414 if (current->_top < block_size_in_oops) { | |
415 break; | |
416 } | |
417 } | |
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418 |
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419 /* |
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420 * JVMTI data structures may also contain weak oops. The iteration of them |
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421 * is placed here so that we don't need to add it to each of the collectors. |
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422 */ |
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423 JvmtiExport::weak_oops_do(is_alive, f); |
0 | 424 } |
425 | |
426 | |
427 jobject JNIHandleBlock::allocate_handle(oop obj) { | |
428 assert(Universe::heap()->is_in_reserved(obj), "sanity check"); | |
429 if (_top == 0) { | |
430 // This is the first allocation or the initial block got zapped when | |
431 // entering a native function. If we have any following blocks they are | |
432 // not valid anymore. | |
433 for (JNIHandleBlock* current = _next; current != NULL; | |
434 current = current->_next) { | |
435 assert(current->_last == NULL, "only first block should have _last set"); | |
436 assert(current->_free_list == NULL, | |
437 "only first block should have _free_list set"); | |
438 current->_top = 0; | |
439 if (ZapJNIHandleArea) current->zap(); | |
440 } | |
441 // Clear initial block | |
442 _free_list = NULL; | |
443 _allocate_before_rebuild = 0; | |
444 _last = this; | |
445 if (ZapJNIHandleArea) zap(); | |
446 } | |
447 | |
448 // Try last block | |
449 if (_last->_top < block_size_in_oops) { | |
450 oop* handle = &(_last->_handles)[_last->_top++]; | |
451 *handle = obj; | |
452 return (jobject) handle; | |
453 } | |
454 | |
455 // Try free list | |
456 if (_free_list != NULL) { | |
457 oop* handle = _free_list; | |
458 _free_list = (oop*) *_free_list; | |
459 *handle = obj; | |
460 return (jobject) handle; | |
461 } | |
462 // Check if unused block follow last | |
463 if (_last->_next != NULL) { | |
464 // update last and retry | |
465 _last = _last->_next; | |
466 return allocate_handle(obj); | |
467 } | |
468 | |
469 // No space available, we have to rebuild free list or expand | |
470 if (_allocate_before_rebuild == 0) { | |
471 rebuild_free_list(); // updates _allocate_before_rebuild counter | |
472 } else { | |
473 // Append new block | |
474 Thread* thread = Thread::current(); | |
475 Handle obj_handle(thread, obj); | |
476 // This can block, so we need to preserve obj accross call. | |
477 _last->_next = JNIHandleBlock::allocate_block(thread); | |
478 _last = _last->_next; | |
479 _allocate_before_rebuild--; | |
480 obj = obj_handle(); | |
481 } | |
482 return allocate_handle(obj); // retry | |
483 } | |
484 | |
485 | |
486 void JNIHandleBlock::rebuild_free_list() { | |
487 assert(_allocate_before_rebuild == 0 && _free_list == NULL, "just checking"); | |
488 int free = 0; | |
489 int blocks = 0; | |
490 for (JNIHandleBlock* current = this; current != NULL; current = current->_next) { | |
491 for (int index = 0; index < current->_top; index++) { | |
492 oop* handle = &(current->_handles)[index]; | |
493 if (*handle == JNIHandles::deleted_handle()) { | |
494 // this handle was cleared out by a delete call, reuse it | |
495 *handle = (oop) _free_list; | |
496 _free_list = handle; | |
497 free++; | |
498 } | |
499 } | |
500 // we should not rebuild free list if there are unused handles at the end | |
501 assert(current->_top == block_size_in_oops, "just checking"); | |
502 blocks++; | |
503 } | |
504 // Heuristic: if more than half of the handles are free we rebuild next time | |
505 // as well, otherwise we append a corresponding number of new blocks before | |
506 // attempting a free list rebuild again. | |
507 int total = blocks * block_size_in_oops; | |
508 int extra = total - 2*free; | |
509 if (extra > 0) { | |
510 // Not as many free handles as we would like - compute number of new blocks to append | |
511 _allocate_before_rebuild = (extra + block_size_in_oops - 1) / block_size_in_oops; | |
512 } | |
513 if (TraceJNIHandleAllocation) { | |
514 tty->print_cr("Rebuild free list JNIHandleBlock " INTPTR_FORMAT " blocks=%d used=%d free=%d add=%d", | |
515 this, blocks, total-free, free, _allocate_before_rebuild); | |
516 } | |
517 } | |
518 | |
519 | |
520 bool JNIHandleBlock::contains(jobject handle) const { | |
521 return ((jobject)&_handles[0] <= handle && handle<(jobject)&_handles[_top]); | |
522 } | |
523 | |
524 | |
525 bool JNIHandleBlock::chain_contains(jobject handle) const { | |
526 for (JNIHandleBlock* current = (JNIHandleBlock*) this; current != NULL; current = current->_next) { | |
527 if (current->contains(handle)) { | |
528 return true; | |
529 } | |
530 } | |
531 return false; | |
532 } | |
533 | |
534 | |
535 int JNIHandleBlock::length() const { | |
536 int result = 1; | |
537 for (JNIHandleBlock* current = _next; current != NULL; current = current->_next) { | |
538 result++; | |
539 } | |
540 return result; | |
541 } | |
542 | |
543 // This method is not thread-safe, i.e., must be called whule holding a lock on the | |
544 // structure. | |
545 long JNIHandleBlock::memory_usage() const { | |
546 return length() * sizeof(JNIHandleBlock); | |
547 } | |
548 | |
549 | |
550 #ifndef PRODUCT | |
551 | |
552 bool JNIHandleBlock::any_contains(jobject handle) { | |
553 for (JNIHandleBlock* current = _block_list; current != NULL; current = current->_block_list_link) { | |
554 if (current->contains(handle)) { | |
555 return true; | |
556 } | |
557 } | |
558 return false; | |
559 } | |
560 | |
561 void JNIHandleBlock::print_statistics() { | |
562 int used_blocks = 0; | |
563 int free_blocks = 0; | |
564 int used_handles = 0; | |
565 int free_handles = 0; | |
566 JNIHandleBlock* block = _block_list; | |
567 while (block != NULL) { | |
568 if (block->_top > 0) { | |
569 used_blocks++; | |
570 } else { | |
571 free_blocks++; | |
572 } | |
573 used_handles += block->_top; | |
574 free_handles += (block_size_in_oops - block->_top); | |
575 block = block->_block_list_link; | |
576 } | |
577 tty->print_cr("JNIHandleBlocks statistics"); | |
578 tty->print_cr("- blocks allocated: %d", used_blocks + free_blocks); | |
579 tty->print_cr("- blocks in use: %d", used_blocks); | |
580 tty->print_cr("- blocks free: %d", free_blocks); | |
581 tty->print_cr("- handles in use: %d", used_handles); | |
582 tty->print_cr("- handles free: %d", free_handles); | |
583 } | |
584 | |
585 #endif |