1 /*
2 * Copyright (c) 2016, 2019, 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 "classfile/javaClasses.hpp"
27 #include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
28 #include "jfr/recorder/service/jfrOptionSet.hpp"
29 #include "jfr/recorder/storage/jfrMemorySpace.inline.hpp"
30 #include "jfr/recorder/repository/jfrChunkWriter.hpp"
31 #include "jfr/recorder/storage/jfrStorageUtils.inline.hpp"
32 #include "jfr/recorder/stringpool/jfrStringPool.hpp"
33 #include "jfr/recorder/stringpool/jfrStringPoolWriter.hpp"
34 #include "jfr/utilities/jfrTypes.hpp"
35 #include "runtime/atomic.hpp"
36 #include "runtime/mutexLocker.hpp"
37 #include "runtime/orderAccess.hpp"
38 #include "runtime/safepoint.hpp"
39 #include "runtime/thread.inline.hpp"
40
41 typedef JfrStringPool::Buffer* BufferPtr;
42
43 static JfrStringPool* _instance = NULL;
44
45 JfrStringPool& JfrStringPool::instance() {
46 return *_instance;
47 }
48
49 JfrStringPool* JfrStringPool::create(JfrChunkWriter& cw) {
50 assert(_instance == NULL, "invariant");
51 _instance = new JfrStringPool(cw);
52 return _instance;
53 }
54
55 void JfrStringPool::destroy() {
56 assert(_instance != NULL, "invariant");
57 delete _instance;
58 _instance = NULL;
59 }
60
61 JfrStringPool::JfrStringPool(JfrChunkWriter& cw) : _free_list_mspace(NULL), _lock(NULL), _chunkwriter(cw) {}
62
63 JfrStringPool::~JfrStringPool() {
64 if (_free_list_mspace != NULL) {
65 delete _free_list_mspace;
66 }
67 if (_lock != NULL) {
68 delete _lock;
69 }
70 }
71
72 static const size_t unlimited_mspace_size = 0;
73 static const size_t string_pool_cache_count = 2;
74 static const size_t string_pool_buffer_size = 512 * K;
75
76 bool JfrStringPool::initialize() {
77 assert(_free_list_mspace == NULL, "invariant");
78 _free_list_mspace = new JfrStringPoolMspace(string_pool_buffer_size, unlimited_mspace_size, string_pool_cache_count, this);
79 if (_free_list_mspace == NULL || !_free_list_mspace->initialize()) {
80 return false;
81 }
82 assert(_lock == NULL, "invariant");
83 _lock = new Mutex(Monitor::leaf - 1, "Checkpoint mutex", Mutex::_allow_vm_block_flag);
84 return _lock != NULL;
85 }
86
87 /*
88 * If the buffer was a "lease" from the global system, release back.
89 *
90 * The buffer is effectively invalidated for the thread post-return,
91 * and the caller should take means to ensure that it is not referenced any longer.
92 */
93 static void release(BufferPtr buffer, Thread* thread) {
94 assert(buffer != NULL, "invariant");
95 assert(buffer->lease(), "invariant");
96 assert(buffer->acquired_by_self(), "invariant");
97 buffer->clear_lease();
98 buffer->release();
99 }
100
101 BufferPtr JfrStringPool::flush(BufferPtr old, size_t used, size_t requested, Thread* thread) {
102 assert(old != NULL, "invariant");
103 assert(old->lease(), "invariant");
104 if (0 == requested) {
105 // indicates a lease is being returned
106 release(old, thread);
107 return NULL;
108 }
109 // migration of in-flight information
110 BufferPtr const new_buffer = lease_buffer(thread, used + requested);
111 if (new_buffer != NULL) {
112 migrate_outstanding_writes(old, new_buffer, used, requested);
113 }
114 release(old, thread);
115 return new_buffer; // might be NULL
116 }
117
118 static const size_t lease_retry = 10;
119
120 BufferPtr JfrStringPool::lease_buffer(Thread* thread, size_t size /* 0 */) {
121 BufferPtr buffer = mspace_get_free_lease_with_retry(size, instance()._free_list_mspace, lease_retry, thread);
122 if (buffer == NULL) {
123 buffer = mspace_allocate_transient_lease_to_free(size, instance()._free_list_mspace, thread);
124 }
125 assert(buffer->acquired_by_self(), "invariant");
126 assert(buffer->lease(), "invariant");
127 return buffer;
128 }
129
130 bool JfrStringPool::add(bool epoch, jlong id, jstring string, JavaThread* jt) {
131 assert(jt != NULL, "invariant");
132 const bool current_epoch = (JfrTraceIdEpoch::epoch() != 0);
133 if (current_epoch == epoch) {
134 JfrStringPoolWriter writer(jt);
135 writer.write(id);
136 writer.write(string);
137 writer.inc_nof_strings();
138 }
139 return current_epoch;
140 }
141
142 template <template <typename> class Operation>
143 class StringPoolOp {
144 public:
145 typedef JfrStringPoolBuffer Type;
146 private:
147 Operation<Type> _op;
148 Thread* _thread;
149 size_t _strings_processed;
150 public:
151 StringPoolOp() : _op(), _thread(Thread::current()), _strings_processed(0) {}
152 StringPoolOp(JfrChunkWriter& writer, Thread* thread) : _op(writer), _thread(thread), _strings_processed(0) {}
153 bool write(Type* buffer, const u1* data, size_t size) {
154 assert(buffer->acquired_by(_thread) || buffer->retired(), "invariant");
155 const uint64_t nof_strings_used = buffer->string_count();
156 assert(nof_strings_used > 0, "invariant");
157 buffer->set_string_top(buffer->string_top() + nof_strings_used);
158 // "size processed" for string pool buffers is the number of processed string elements
159 _strings_processed += nof_strings_used;
160 return _op.write(buffer, data, size);
161 }
162 size_t processed() { return _strings_processed; }
163 };
164
165 template <typename Type>
166 class StringPoolDiscarderStub {
167 public:
168 bool write(Type* buffer, const u1* data, size_t size) {
169 // stub only, discard happens at higher level
170 return true;
171 }
172 };
173
174 typedef StringPoolOp<UnBufferedWriteToChunk> WriteOperation;
175 typedef StringPoolOp<StringPoolDiscarderStub> DiscardOperation;
176 typedef ExclusiveOp<WriteOperation> ExclusiveWriteOperation;
177 typedef ExclusiveOp<DiscardOperation> ExclusiveDiscardOperation;
178 typedef ReleaseOp<JfrStringPoolMspace> StringPoolReleaseOperation;
179 typedef CompositeOperation<ExclusiveWriteOperation, StringPoolReleaseOperation> StringPoolWriteOperation;
180 typedef CompositeOperation<ExclusiveDiscardOperation, StringPoolReleaseOperation> StringPoolDiscardOperation;
181
182 size_t JfrStringPool::write() {
183 Thread* const thread = Thread::current();
184 WriteOperation wo(_chunkwriter, thread);
185 ExclusiveWriteOperation ewo(wo);
186 StringPoolReleaseOperation spro(_free_list_mspace, thread, false);
187 StringPoolWriteOperation spwo(&ewo, &spro);
188 assert(_free_list_mspace->is_full_empty(), "invariant");
189 process_free_list(spwo, _free_list_mspace);
190 return wo.processed();
191 }
192
193 size_t JfrStringPool::write_at_safepoint() {
194 assert(SafepointSynchronize::is_at_safepoint(), "invariant");
195 return write();
196 }
197
198 size_t JfrStringPool::clear() {
199 DiscardOperation discard_operation;
200 ExclusiveDiscardOperation edo(discard_operation);
201 StringPoolReleaseOperation spro(_free_list_mspace, Thread::current(), false);
202 StringPoolDiscardOperation spdo(&edo, &spro);
203 assert(_free_list_mspace->is_full_empty(), "invariant");
204 process_free_list(spdo, _free_list_mspace);
205 return discard_operation.processed();
206 }
207
208 void JfrStringPool::register_full(BufferPtr t, Thread* thread) {
209 // nothing here at the moment
210 assert(t != NULL, "invariant");
211 assert(t->acquired_by(thread), "invariant");
212 assert(t->retired(), "invariant");
213 }
214
215 void JfrStringPool::lock() {
216 assert(!_lock->owned_by_self(), "invariant");
217 _lock->lock_without_safepoint_check();
218 }
219
220 void JfrStringPool::unlock() {
221 _lock->unlock();
222 }
223
224 #ifdef ASSERT
225 bool JfrStringPool::is_locked() const {
226 return _lock->owned_by_self();
227 }
228 #endif