1 /*
2 * Copyright (c) 1997, 2020, 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 #include "runtime/thread.inline.hpp"
31
32 #ifdef ASSERT
allocate_handle(oop obj)33 oop* HandleArea::allocate_handle(oop obj) {
34 assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark");
35 assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark");
36 assert(oopDesc::is_oop(obj), "not an oop: " INTPTR_FORMAT, p2i(obj));
37 return real_allocate_handle(obj);
38 }
39 #endif
40
41 // Copy constructors and destructors for metadata handles
42 // These do too much to inline.
43 #define DEF_METADATA_HANDLE_FN_NOINLINE(name, type) \
44 name##Handle::name##Handle(const name##Handle &h) { \
45 _value = h._value; \
46 if (_value != NULL) { \
47 assert(_value->is_valid(), "obj is valid"); \
48 if (h._thread != NULL) { \
49 assert(h._thread == Thread::current(), "thread must be current");\
50 _thread = h._thread; \
51 } else { \
52 _thread = Thread::current(); \
53 } \
54 assert(_thread->is_in_live_stack((address)this), "not on stack?"); \
55 _thread->metadata_handles()->push((Metadata*)_value); \
56 } else { \
57 _thread = NULL; \
58 } \
59 } \
60 name##Handle& name##Handle::operator=(const name##Handle &s) { \
61 remove(); \
62 _value = s._value; \
63 if (_value != NULL) { \
64 assert(_value->is_valid(), "obj is valid"); \
65 if (s._thread != NULL) { \
66 assert(s._thread == Thread::current(), "thread must be current");\
67 _thread = s._thread; \
68 } else { \
69 _thread = Thread::current(); \
70 } \
71 assert(_thread->is_in_live_stack((address)this), "not on stack?"); \
72 _thread->metadata_handles()->push((Metadata*)_value); \
73 } else { \
74 _thread = NULL; \
75 } \
76 return *this; \
77 } \
78 inline void name##Handle::remove() { \
79 if (_value != NULL) { \
80 int i = _thread->metadata_handles()->find_from_end((Metadata*)_value); \
81 assert(i!=-1, "not in metadata_handles list"); \
82 _thread->metadata_handles()->remove_at(i); \
83 } \
84 } \
85 name##Handle::~name##Handle () { remove(); } \
86
DEF_METADATA_HANDLE_FN_NOINLINE(method,Method)87 DEF_METADATA_HANDLE_FN_NOINLINE(method, Method)
88 DEF_METADATA_HANDLE_FN_NOINLINE(constantPool, ConstantPool)
89
90
91 static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) {
92 oop* bottom = (oop*) chunk->bottom();
93 oop* top = (oop*) chunk_top;
94 uintx handles_visited = top - bottom;
95 assert(top >= bottom && top <= (oop*) chunk->top(), "just checking");
96 // during GC phase 3, a handle may be a forward pointer that
97 // is not yet valid, so loosen the assertion
98 while (bottom < top) {
99 f->do_oop(bottom++);
100 }
101 return handles_visited;
102 }
103
oops_do(OopClosure * f)104 void HandleArea::oops_do(OopClosure* f) {
105 uintx handles_visited = 0;
106 // First handle the current chunk. It is filled to the high water mark.
107 handles_visited += chunk_oops_do(f, _chunk, _hwm);
108 // Then handle all previous chunks. They are completely filled.
109 Chunk* k = _first;
110 while(k != _chunk) {
111 handles_visited += chunk_oops_do(f, k, k->top());
112 k = k->next();
113 }
114
115 if (_prev != NULL) _prev->oops_do(f);
116 }
117
initialize(Thread * thread)118 void HandleMark::initialize(Thread* thread) {
119 _thread = thread; // Not the current thread during thread creation.
120 // Save area
121 _area = thread->handle_area();
122 // Save current top
123 _chunk = _area->_chunk;
124 _hwm = _area->_hwm;
125 _max = _area->_max;
126 _size_in_bytes = _area->_size_in_bytes;
127 debug_only(_area->_handle_mark_nesting++);
128 assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks");
129
130 // Link this in the thread
131 set_previous_handle_mark(thread->last_handle_mark());
132 thread->set_last_handle_mark(this);
133 }
134
~HandleMark()135 HandleMark::~HandleMark() {
136 assert(_area == _thread->handle_area(), "sanity check");
137 assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" );
138
139 pop_and_restore();
140 #ifdef ASSERT
141 // clear out first chunk (to detect allocation bugs)
142 if (ZapVMHandleArea) {
143 memset(_hwm, badHandleValue, _max - _hwm);
144 }
145 #endif
146
147 // Unlink this from the thread
148 _thread->set_last_handle_mark(previous_handle_mark());
149 }
150
chop_later_chunks()151 void HandleMark::chop_later_chunks() {
152 // reset arena size before delete chunks. Otherwise, the total
153 // arena size could exceed total chunk size
154 _area->set_size_in_bytes(size_in_bytes());
155 _chunk->next_chop();
156 }
157
operator new(size_t size)158 void* HandleMark::operator new(size_t size) throw() {
159 return AllocateHeap(size, mtThread);
160 }
161
operator new[](size_t size)162 void* HandleMark::operator new [] (size_t size) throw() {
163 return AllocateHeap(size, mtThread);
164 }
165
operator delete(void * p)166 void HandleMark::operator delete(void* p) {
167 FreeHeap(p);
168 }
169
operator delete[](void * p)170 void HandleMark::operator delete[](void* p) {
171 FreeHeap(p);
172 }
173
174 #ifdef ASSERT
175
NoHandleMark()176 NoHandleMark::NoHandleMark() {
177 HandleArea* area = Thread::current()->handle_area();
178 area->_no_handle_mark_nesting++;
179 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
180 }
181
182
~NoHandleMark()183 NoHandleMark::~NoHandleMark() {
184 HandleArea* area = Thread::current()->handle_area();
185 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
186 area->_no_handle_mark_nesting--;
187 }
188
189
ResetNoHandleMark()190 ResetNoHandleMark::ResetNoHandleMark() {
191 HandleArea* area = Thread::current()->handle_area();
192 _no_handle_mark_nesting = area->_no_handle_mark_nesting;
193 area->_no_handle_mark_nesting = 0;
194 }
195
196
~ResetNoHandleMark()197 ResetNoHandleMark::~ResetNoHandleMark() {
198 HandleArea* area = Thread::current()->handle_area();
199 area->_no_handle_mark_nesting = _no_handle_mark_nesting;
200 }
201
202 #endif // ASSERT
203