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