1 /* 2 * Copyright (c) 1997, 2018, 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/atomic.hpp" 30 #include "runtime/handles.inline.hpp" 31 #include "runtime/thread.inline.hpp" 32 33 bool Handle::operator == (oop o) const { 34 return oopDesc::equals(obj(), o); 35 } 36 37 bool Handle::operator == (const Handle& h) const { 38 return oopDesc::equals(obj(), h.obj()); 39 } 40 41 #ifdef ASSERT 42 oop* HandleArea::allocate_handle(oop obj) { 43 assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark"); 44 assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark"); 45 assert(oopDesc::is_oop(obj), "not an oop: " INTPTR_FORMAT, p2i(obj)); 46 return real_allocate_handle(obj); 47 } 48 #endif 49 50 // Copy constructors and destructors for metadata handles 51 // These do too much to inline. 52 #define DEF_METADATA_HANDLE_FN_NOINLINE(name, type) \ 53 name##Handle::name##Handle(const name##Handle &h) { \ 54 _value = h._value; \ 55 if (_value != NULL) { \ 56 assert(_value->is_valid(), "obj is valid"); \ 57 if (h._thread != NULL) { \ 58 assert(h._thread == Thread::current(), "thread must be current");\ 59 _thread = h._thread; \ 60 } else { \ 61 _thread = Thread::current(); \ 62 } \ 63 assert (_thread->is_in_stack((address)this), "not on stack?"); \ 64 _thread->metadata_handles()->push((Metadata*)_value); \ 65 } else { \ 66 _thread = NULL; \ 67 } \ 68 } \ 69 name##Handle& name##Handle::operator=(const name##Handle &s) { \ 70 remove(); \ 71 _value = s._value; \ 72 if (_value != NULL) { \ 73 assert(_value->is_valid(), "obj is valid"); \ 74 if (s._thread != NULL) { \ 75 assert(s._thread == Thread::current(), "thread must be current");\ 76 _thread = s._thread; \ 77 } else { \ 78 _thread = Thread::current(); \ 79 } \ 80 assert (_thread->is_in_stack((address)this), "not on stack?"); \ 81 _thread->metadata_handles()->push((Metadata*)_value); \ 82 } else { \ 83 _thread = NULL; \ 84 } \ 85 return *this; \ 86 } \ 87 inline void name##Handle::remove() { \ 88 if (_value != NULL) { \ 89 int i = _thread->metadata_handles()->find_from_end((Metadata*)_value); \ 90 assert(i!=-1, "not in metadata_handles list"); \ 91 _thread->metadata_handles()->remove_at(i); \ 92 } \ 93 } \ 94 name##Handle::~name##Handle () { remove(); } \ 95 96 DEF_METADATA_HANDLE_FN_NOINLINE(method, Method) 97 DEF_METADATA_HANDLE_FN_NOINLINE(constantPool, ConstantPool) 98 99 100 static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) { 101 oop* bottom = (oop*) chunk->bottom(); 102 oop* top = (oop*) chunk_top; 103 uintx handles_visited = top - bottom; 104 assert(top >= bottom && top <= (oop*) chunk->top(), "just checking"); 105 // during GC phase 3, a handle may be a forward pointer that 106 // is not yet valid, so loosen the assertion 107 while (bottom < top) { 108 f->do_oop(bottom++); 109 } 110 return handles_visited; 111 } 112 113 // Used for debugging handle allocation. 114 NOT_PRODUCT(jint _nof_handlemarks = 0;) 115 116 void HandleArea::oops_do(OopClosure* f) { 117 uintx handles_visited = 0; 118 // First handle the current chunk. It is filled to the high water mark. 119 handles_visited += chunk_oops_do(f, _chunk, _hwm); 120 // Then handle all previous chunks. They are completely filled. 121 Chunk* k = _first; 122 while(k != _chunk) { 123 handles_visited += chunk_oops_do(f, k, k->top()); 124 k = k->next(); 125 } 126 127 if (_prev != NULL) _prev->oops_do(f); 128 } 129 130 void HandleMark::initialize(Thread* thread) { 131 _thread = thread; 132 // Save area 133 _area = thread->handle_area(); 134 // Save current top 135 _chunk = _area->_chunk; 136 _hwm = _area->_hwm; 137 _max = _area->_max; 138 _size_in_bytes = _area->_size_in_bytes; 139 debug_only(_area->_handle_mark_nesting++); 140 assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks"); 141 debug_only(Atomic::inc(&_nof_handlemarks);) 142 143 // Link this in the thread 144 set_previous_handle_mark(thread->last_handle_mark()); 145 thread->set_last_handle_mark(this); 146 } 147 148 149 HandleMark::~HandleMark() { 150 HandleArea* area = _area; // help compilers with poor alias analysis 151 assert(area == _thread->handle_area(), "sanity check"); 152 assert(area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" ); 153 debug_only(area->_handle_mark_nesting--); 154 155 // Delete later chunks 156 if( _chunk->next() ) { 157 // reset arena size before delete chunks. Otherwise, the total 158 // arena size could exceed total chunk size 159 assert(area->size_in_bytes() > size_in_bytes(), "Sanity check"); 160 area->set_size_in_bytes(size_in_bytes()); 161 _chunk->next_chop(); 162 } else { 163 assert(area->size_in_bytes() == size_in_bytes(), "Sanity check"); 164 } 165 // Roll back arena to saved top markers 166 area->_chunk = _chunk; 167 area->_hwm = _hwm; 168 area->_max = _max; 169 #ifdef ASSERT 170 // clear out first chunk (to detect allocation bugs) 171 if (ZapVMHandleArea) { 172 memset(_hwm, badHandleValue, _max - _hwm); 173 } 174 Atomic::dec(&_nof_handlemarks); 175 #endif 176 177 // Unlink this from the thread 178 _thread->set_last_handle_mark(previous_handle_mark()); 179 } 180 181 void* HandleMark::operator new(size_t size) throw() { 182 return AllocateHeap(size, mtThread); 183 } 184 185 void* HandleMark::operator new [] (size_t size) throw() { 186 return AllocateHeap(size, mtThread); 187 } 188 189 void HandleMark::operator delete(void* p) { 190 FreeHeap(p); 191 } 192 193 void HandleMark::operator delete[](void* p) { 194 FreeHeap(p); 195 } 196 197 #ifdef ASSERT 198 199 NoHandleMark::NoHandleMark() { 200 HandleArea* area = Thread::current()->handle_area(); 201 area->_no_handle_mark_nesting++; 202 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" ); 203 } 204 205 206 NoHandleMark::~NoHandleMark() { 207 HandleArea* area = Thread::current()->handle_area(); 208 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" ); 209 area->_no_handle_mark_nesting--; 210 } 211 212 213 ResetNoHandleMark::ResetNoHandleMark() { 214 HandleArea* area = Thread::current()->handle_area(); 215 _no_handle_mark_nesting = area->_no_handle_mark_nesting; 216 area->_no_handle_mark_nesting = 0; 217 } 218 219 220 ResetNoHandleMark::~ResetNoHandleMark() { 221 HandleArea* area = Thread::current()->handle_area(); 222 area->_no_handle_mark_nesting = _no_handle_mark_nesting; 223 } 224 225 #endif // ASSERT