handles.cpp revision 3602:da91efe96a93
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 */ 24 25#include "precompiled.hpp" 26#include "memory/allocation.inline.hpp" 27#include "oops/constantPool.hpp" 28#include "oops/oop.inline.hpp" 29#include "runtime/handles.inline.hpp" 30#ifdef TARGET_OS_FAMILY_linux 31# include "os_linux.inline.hpp" 32# include "thread_linux.inline.hpp" 33#endif 34#ifdef TARGET_OS_FAMILY_solaris 35# include "os_solaris.inline.hpp" 36# include "thread_solaris.inline.hpp" 37#endif 38#ifdef TARGET_OS_FAMILY_windows 39# include "os_windows.inline.hpp" 40# include "thread_windows.inline.hpp" 41#endif 42#ifdef TARGET_OS_FAMILY_bsd 43# include "os_bsd.inline.hpp" 44# include "thread_bsd.inline.hpp" 45#endif 46 47#ifdef ASSERT 48oop* HandleArea::allocate_handle(oop obj) { 49 assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark"); 50 assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark"); 51 assert(SharedSkipVerify || obj->is_oop(), "sanity check"); 52 return real_allocate_handle(obj); 53} 54 55Handle::Handle(Thread* thread, oop obj) { 56 assert(thread == Thread::current(), "sanity check"); 57 if (obj == NULL) { 58 _handle = NULL; 59 } else { 60 _handle = thread->handle_area()->allocate_handle(obj); 61 } 62} 63 64#endif 65 66static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) { 67 oop* bottom = (oop*) chunk->bottom(); 68 oop* top = (oop*) chunk_top; 69 uintx handles_visited = top - bottom; 70 assert(top >= bottom && top <= (oop*) chunk->top(), "just checking"); 71 // during GC phase 3, a handle may be a forward pointer that 72 // is not yet valid, so loosen the assertion 73 while (bottom < top) { 74 // This test can be moved up but for now check every oop. 75 76 assert((*bottom)->is_oop(), "handle should point to oop"); 77 78 f->do_oop(bottom++); 79 } 80 return handles_visited; 81} 82 83// Used for debugging handle allocation. 84NOT_PRODUCT(jint _nof_handlemarks = 0;) 85 86void HandleArea::oops_do(OopClosure* f) { 87 uintx handles_visited = 0; 88 // First handle the current chunk. It is filled to the high water mark. 89 handles_visited += chunk_oops_do(f, _chunk, _hwm); 90 // Then handle all previous chunks. They are completely filled. 91 Chunk* k = _first; 92 while(k != _chunk) { 93 handles_visited += chunk_oops_do(f, k, k->top()); 94 k = k->next(); 95 } 96 97 // The thread local handle areas should not get very large 98 if (TraceHandleAllocation && handles_visited > TotalHandleAllocationLimit) { 99#ifdef ASSERT 100 warning("%d: Visited in HandleMark : %d", 101 _nof_handlemarks, handles_visited); 102#else 103 warning("Visited in HandleMark : %d", handles_visited); 104#endif 105 } 106 if (_prev != NULL) _prev->oops_do(f); 107} 108 109void HandleMark::initialize(Thread* thread) { 110 _thread = thread; 111 // Save area 112 _area = thread->handle_area(); 113 // Save current top 114 _chunk = _area->_chunk; 115 _hwm = _area->_hwm; 116 _max = _area->_max; 117 _size_in_bytes = _area->_size_in_bytes; 118 debug_only(_area->_handle_mark_nesting++); 119 assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks"); 120 debug_only(Atomic::inc(&_nof_handlemarks);) 121 122 // Link this in the thread 123 set_previous_handle_mark(thread->last_handle_mark()); 124 thread->set_last_handle_mark(this); 125} 126 127 128HandleMark::~HandleMark() { 129 HandleArea* area = _area; // help compilers with poor alias analysis 130 assert(area == _thread->handle_area(), "sanity check"); 131 assert(area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" ); 132 debug_only(area->_handle_mark_nesting--); 133 134 // Debug code to trace the number of handles allocated per mark/ 135#ifdef ASSERT 136 if (TraceHandleAllocation) { 137 size_t handles = 0; 138 Chunk *c = _chunk->next(); 139 if (c == NULL) { 140 handles = area->_hwm - _hwm; // no new chunk allocated 141 } else { 142 handles = _max - _hwm; // add rest in first chunk 143 while(c != NULL) { 144 handles += c->length(); 145 c = c->next(); 146 } 147 handles -= area->_max - area->_hwm; // adjust for last trunk not full 148 } 149 handles /= sizeof(void *); // Adjust for size of a handle 150 if (handles > HandleAllocationLimit) { 151 // Note: _nof_handlemarks is only set in debug mode 152 warning("%d: Allocated in HandleMark : %d", _nof_handlemarks, handles); 153 } 154 155 tty->print_cr("Handles %d", handles); 156 } 157#endif 158 159 // Delete later chunks 160 if( _chunk->next() ) { 161 _chunk->next_chop(); 162 } 163 // Roll back arena to saved top markers 164 area->_chunk = _chunk; 165 area->_hwm = _hwm; 166 area->_max = _max; 167 area->set_size_in_bytes(_size_in_bytes); 168#ifdef ASSERT 169 // clear out first chunk (to detect allocation bugs) 170 if (ZapVMHandleArea) { 171 memset(_hwm, badHandleValue, _max - _hwm); 172 } 173 Atomic::dec(&_nof_handlemarks); 174#endif 175 176 // Unlink this from the thread 177 _thread->set_last_handle_mark(previous_handle_mark()); 178} 179 180#ifdef ASSERT 181 182NoHandleMark::NoHandleMark() { 183 HandleArea* area = Thread::current()->handle_area(); 184 area->_no_handle_mark_nesting++; 185 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" ); 186} 187 188 189NoHandleMark::~NoHandleMark() { 190 HandleArea* area = Thread::current()->handle_area(); 191 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" ); 192 area->_no_handle_mark_nesting--; 193} 194 195 196ResetNoHandleMark::ResetNoHandleMark() { 197 HandleArea* area = Thread::current()->handle_area(); 198 _no_handle_mark_nesting = area->_no_handle_mark_nesting; 199 area->_no_handle_mark_nesting = 0; 200} 201 202 203ResetNoHandleMark::~ResetNoHandleMark() { 204 HandleArea* area = Thread::current()->handle_area(); 205 area->_no_handle_mark_nesting = _no_handle_mark_nesting; 206} 207 208#endif 209