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