1 /*
2 * Copyright (c) 1997, 2010, 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/oop.inline.hpp"
28 #include "runtime/handles.inline.hpp"
29 #ifdef TARGET_OS_FAMILY_linux
30 # include "os_linux.inline.hpp"
31 # include "thread_linux.inline.hpp"
32 #endif
33 #ifdef TARGET_OS_FAMILY_solaris
34 # include "os_solaris.inline.hpp"
35 # include "thread_solaris.inline.hpp"
36 #endif
37 #ifdef TARGET_OS_FAMILY_windows
38 # include "os_windows.inline.hpp"
39 # include "thread_windows.inline.hpp"
40 #endif
41
42 #ifdef ASSERT
43 oop* HandleArea::allocate_handle(oop obj) {
44 assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark");
45 assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark");
46 assert(SharedSkipVerify || obj->is_oop(), "sanity check");
47 return real_allocate_handle(obj);
48 }
49
50 Handle::Handle(Thread* thread, oop obj) {
51 assert(thread == Thread::current(), "sanity check");
52 if (obj == NULL) {
53 _handle = NULL;
54 } else {
55 _handle = thread->handle_area()->allocate_handle(obj);
56 }
57 }
58
59 #endif
60
61 static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) {
62 oop* bottom = (oop*) chunk->bottom();
63 oop* top = (oop*) chunk_top;
64 uintx handles_visited = top - bottom;
65 assert(top >= bottom && top <= (oop*) chunk->top(), "just checking");
66 // during GC phase 3, a handle may be a forward pointer that
67 // is not yet valid, so loosen the assertion
68 while (bottom < top) {
69 // assert((*bottom)->is_oop(), "handle should point to oop");
70 assert(Universe::heap()->is_in(*bottom), "handle should be valid heap address");
71 f->do_oop(bottom++);
72 }
73 return handles_visited;
74 }
75
76 // Used for debugging handle allocation.
77 NOT_PRODUCT(jint _nof_handlemarks = 0;)
78
79 void HandleArea::oops_do(OopClosure* f) {
80 uintx handles_visited = 0;
81 // First handle the current chunk. It is filled to the high water mark.
82 handles_visited += chunk_oops_do(f, _chunk, _hwm);
83 // Then handle all previous chunks. They are completely filled.
84 Chunk* k = _first;
85 while(k != _chunk) {
86 handles_visited += chunk_oops_do(f, k, k->top());
87 k = k->next();
88 }
89
90 // The thread local handle areas should not get very large
91 if (TraceHandleAllocation && handles_visited > TotalHandleAllocationLimit) {
92 #ifdef ASSERT
93 warning("%d: Visited in HandleMark : %d",
94 _nof_handlemarks, handles_visited);
95 #else
96 warning("Visited in HandleMark : %d", handles_visited);
97 #endif
98 }
99 if (_prev != NULL) _prev->oops_do(f);
100 }
101
102 void HandleMark::initialize(Thread* thread) {
103 _thread = thread;
104 // Save area
105 _area = thread->handle_area();
106 // Save current top
107 _chunk = _area->_chunk;
108 _hwm = _area->_hwm;
109 _max = _area->_max;
110 NOT_PRODUCT(_size_in_bytes = _area->_size_in_bytes;)
111 debug_only(_area->_handle_mark_nesting++);
112 assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks");
113 debug_only(Atomic::inc(&_nof_handlemarks);)
114
115 // Link this in the thread
116 set_previous_handle_mark(thread->last_handle_mark());
117 thread->set_last_handle_mark(this);
118 }
119
120
121 HandleMark::~HandleMark() {
122 HandleArea* area = _area; // help compilers with poor alias analysis
123 assert(area == _thread->handle_area(), "sanity check");
124 assert(area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" );
125 debug_only(area->_handle_mark_nesting--);
126
127 // Debug code to trace the number of handles allocated per mark/
128 #ifdef ASSERT
129 if (TraceHandleAllocation) {
130 size_t handles = 0;
131 Chunk *c = _chunk->next();
132 if (c == NULL) {
133 handles = area->_hwm - _hwm; // no new chunk allocated
134 } else {
135 handles = _max - _hwm; // add rest in first chunk
136 while(c != NULL) {
137 handles += c->length();
138 c = c->next();
139 }
140 handles -= area->_max - area->_hwm; // adjust for last trunk not full
141 }
142 handles /= sizeof(void *); // Adjust for size of a handle
143 if (handles > HandleAllocationLimit) {
144 // Note: _nof_handlemarks is only set in debug mode
145 warning("%d: Allocated in HandleMark : %d", _nof_handlemarks, handles);
146 }
147 }
148 #endif
149
150 // Delete later chunks
151 if( _chunk->next() ) {
152 _chunk->next_chop();
153 }
154 // Roll back arena to saved top markers
155 area->_chunk = _chunk;
156 area->_hwm = _hwm;
157 area->_max = _max;
158 NOT_PRODUCT(area->set_size_in_bytes(_size_in_bytes);)
159 #ifdef ASSERT
160 // clear out first chunk (to detect allocation bugs)
161 if (ZapVMHandleArea) {
162 memset(_hwm, badHandleValue, _max - _hwm);
163 }
164 Atomic::dec(&_nof_handlemarks);
165 #endif
166
167 // Unlink this from the thread
168 _thread->set_last_handle_mark(previous_handle_mark());
169 }
170
171 #ifdef ASSERT
172
173 NoHandleMark::NoHandleMark() {
174 HandleArea* area = Thread::current()->handle_area();
175 area->_no_handle_mark_nesting++;
176 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
177 }
178
179
180 NoHandleMark::~NoHandleMark() {
181 HandleArea* area = Thread::current()->handle_area();
182 assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
183 area->_no_handle_mark_nesting--;
184 }
185
186
187 ResetNoHandleMark::ResetNoHandleMark() {
188 HandleArea* area = Thread::current()->handle_area();
189 _no_handle_mark_nesting = area->_no_handle_mark_nesting;
190 area->_no_handle_mark_nesting = 0;
191 }
192
193
194 ResetNoHandleMark::~ResetNoHandleMark() {
195 HandleArea* area = Thread::current()->handle_area();
196 area->_no_handle_mark_nesting = _no_handle_mark_nesting;
197 }
198
199 #endif