1 /*
2 * Copyright (c) 2016, 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 "classfile/javaClasses.inline.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 "logging/log.hpp"
36 #include "runtime/atomic.hpp"
37 #include "runtime/mutexLocker.hpp"
38 #include "runtime/orderAccess.inline.hpp"
39 #include "runtime/safepoint.hpp"
40 #include "runtime/thread.inline.hpp"
41
42 typedef JfrStringPool::Buffer* BufferPtr;
43
44 static JfrStringPool* _instance = NULL;
45
46 JfrStringPool& JfrStringPool::instance() {
47 return *_instance;
48 }
49
50 JfrStringPool* JfrStringPool::create(JfrChunkWriter& cw) {
51 assert(_instance == NULL, "invariant");
52 _instance = new JfrStringPool(cw);
53 return _instance;
54 }
55
56 void JfrStringPool::destroy() {
57 assert(_instance != NULL, "invariant");
58 delete _instance;
59 _instance = NULL;
60 }
61
62 JfrStringPool::JfrStringPool(JfrChunkWriter& cw) : _free_list_mspace(NULL), _lock(NULL), _chunkwriter(cw) {}
63
64 JfrStringPool::~JfrStringPool() {
65 if (_free_list_mspace != NULL) {
66 delete _free_list_mspace;
67 }
68 if (_lock != NULL) {
69 delete _lock;
70 }
71 }
72
73 static const size_t unlimited_mspace_size = 0;
74 static const size_t string_pool_cache_count = 2;
75 static const size_t string_pool_buffer_size = 512 * K;
76
77 bool JfrStringPool::initialize() {
78 assert(_free_list_mspace == NULL, "invariant");
79 _free_list_mspace = new JfrStringPoolMspace(string_pool_buffer_size, unlimited_mspace_size, string_pool_cache_count, this);
80 if (_free_list_mspace == NULL || !_free_list_mspace->initialize()) {
81 return false;
82 }
83 assert(_lock == NULL, "invariant");
84 _lock = new Mutex(Monitor::leaf - 1, "Checkpoint mutex", Mutex::_allow_vm_block_flag, Monitor::_safepoint_check_never);
85 return _lock != NULL;
86 }
87
88 /*
89 * If the buffer was a "lease" from the global system, release back.
90 *
91 * The buffer is effectively invalidated for the thread post-return,
92 * and the caller should take means to ensure that it is not referenced any longer.
93 */
94 static void release(BufferPtr buffer, Thread* thread) {
95 assert(buffer != NULL, "invariant");
96 assert(buffer->lease(), "invariant");
97 assert(buffer->acquired_by_self(), "invariant");
98 buffer->clear_lease();
99 buffer->release();
100 }
101
102 BufferPtr JfrStringPool::flush(BufferPtr old, size_t used, size_t requested, Thread* thread) {
103 assert(old != NULL, "invariant");
104 assert(old->lease(), "invariant");
105 if (0 == requested) {
106 // indicates a lease is being returned
107 release(old, thread);
108 return NULL;
109 }
110 // migration of in-flight information
111 BufferPtr const new_buffer = lease_buffer(thread, used + requested);
112 if (new_buffer != NULL) {
113 migrate_outstanding_writes(old, new_buffer, used, requested);
114 }
115 release(old, thread);
116 return new_buffer; // might be NULL
117 }
118
119 static const size_t lease_retry = 10;
120
121 BufferPtr JfrStringPool::lease_buffer(Thread* thread, size_t size /* 0 */) {
122 BufferPtr buffer = mspace_get_free_lease_with_retry(size, instance()._free_list_mspace, lease_retry, thread);
123 if (buffer == NULL) {
124 buffer = mspace_allocate_transient_lease_to_free(size, instance()._free_list_mspace, thread);
125 }
126 assert(buffer->acquired_by_self(), "invariant");
127 assert(buffer->lease(), "invariant");
128 return buffer;
129 }
130
131 bool JfrStringPool::add(bool epoch, jlong id, jstring string, JavaThread* jt) {
132 assert(jt != NULL, "invariant");
133 const bool current_epoch = JfrTraceIdEpoch::epoch();
134 if (current_epoch == epoch) {
135 JfrStringPoolWriter writer(jt);
136 writer.write(id);
137 writer.write(string);
138 writer.inc_nof_strings();
139 }
140 return current_epoch;
141 }
142
143 class StringPoolWriteOp {
144 public:
145 typedef JfrStringPoolBuffer Type;
146 private:
147 UnBufferedWriteToChunk<Type> _writer;
148 Thread* _thread;
149 size_t _strings_processed;
150 public:
151 StringPoolWriteOp(JfrChunkWriter& writer, Thread* thread) : _writer(writer), _thread(thread), _strings_processed(0) {}
152 bool write(Type* buffer, const u1* data, size_t size) {
153 buffer->acquire(_thread); // blocking
154 const u4 nof_strings_used = (const u4)buffer->string_count();
155 assert(nof_strings_used > 0, "invariant");
156 buffer->set_string_top(buffer->string_top() + nof_strings_used);
157 // "size processed" for string pool buffers is the number of processed string elements
158 _strings_processed += nof_strings_used;
159 const bool ret = _writer.write(buffer, data, size);
160 buffer->release();
161 return ret;
162 }
163 size_t processed() { return _strings_processed; }
164 };
165
166 typedef StringPoolWriteOp WriteOperation;
167 typedef ConcurrentWriteOp<WriteOperation> ConcurrentWriteOperation;
168
169 size_t JfrStringPool::write() {
170 Thread* const thread = Thread::current();
171 WriteOperation wo(_chunkwriter, thread);
172 ConcurrentWriteOperation cwo(wo);
173 assert(_free_list_mspace->is_full_empty(), "invariant");
174 process_free_list(cwo, _free_list_mspace);
175 return wo.processed();
176 }
177
178 typedef MutexedWriteOp<WriteOperation> MutexedWriteOperation;
179 typedef ReleaseOp<JfrStringPoolMspace> StringPoolReleaseOperation;
180 typedef CompositeOperation<MutexedWriteOperation, StringPoolReleaseOperation> StringPoolWriteOperation;
181
182 size_t JfrStringPool::write_at_safepoint() {
183 assert(SafepointSynchronize::is_at_safepoint(), "invariant");
184 Thread* const thread = Thread::current();
185 WriteOperation wo(_chunkwriter, thread);
186 MutexedWriteOperation mwo(wo);
187 StringPoolReleaseOperation spro(_free_list_mspace, thread, false);
188 StringPoolWriteOperation spwo(&mwo, &spro);
189 assert(_free_list_mspace->is_full_empty(), "invariant");
190 process_free_list(spwo, _free_list_mspace);
191 return wo.processed();
192 }
193
194 class StringPoolBufferDiscarder {
195 private:
196 Thread* _thread;
197 size_t _processed;
198 public:
199 typedef JfrStringPoolBuffer Type;
200 StringPoolBufferDiscarder() : _thread(Thread::current()), _processed(0) {}
201 bool process(Type* buffer) {
202 buffer->acquire(_thread); // serialized access
203 const u1* const current_top = buffer->top();
204 const size_t unflushed_size = buffer->pos() - current_top;
205 if (unflushed_size == 0) {
206 assert(buffer->string_count() == 0, "invariant");
207 buffer->release();
208 return true;
209 }
210 buffer->set_top(current_top + unflushed_size);
211 const u4 nof_strings_used = buffer->string_count();
212 buffer->set_string_top(buffer->string_top() + nof_strings_used);
213 // "size processed" for string pool buffers is the number of string elements
214 _processed += nof_strings_used;
215 buffer->release();
216 return true;
217 }
218 size_t processed() const { return _processed; }
219 };
220
221 size_t JfrStringPool::clear() {
222 StringPoolBufferDiscarder discard_operation;
223 assert(_free_list_mspace->is_full_empty(), "invariant");
224 process_free_list(discard_operation, _free_list_mspace);
225 return discard_operation.processed();
226 }
227
228 void JfrStringPool::register_full(BufferPtr t, Thread* thread) {
229 // nothing here at the moment
230 assert(t->retired(), "invariant");
231 }
232
233 void JfrStringPool::lock() {
234 assert(!_lock->owned_by_self(), "invariant");
235 _lock->lock_without_safepoint_check();
236 }
237
238 void JfrStringPool::unlock() {
239 _lock->unlock();
240 }
241
242 #ifdef ASSERT
243 bool JfrStringPool::is_locked() const {
244 return _lock->owned_by_self();
245 }
246 #endif