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/jfrRecorder.hpp"
28 #include "jfr/recorder/checkpoint/jfrCheckpointManager.hpp"
29 #include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"
30 #include "jfr/recorder/checkpoint/types/jfrTypeManager.hpp"
31 #include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
32 #include "jfr/recorder/service/jfrOptionSet.hpp"
33 #include "jfr/recorder/storage/jfrMemorySpace.inline.hpp"
34 #include "jfr/recorder/storage/jfrStorageUtils.inline.hpp"
35 #include "jfr/recorder/repository/jfrChunkWriter.hpp"
36 #include "jfr/utilities/jfrBigEndian.hpp"
37 #include "jfr/utilities/jfrTypes.hpp"
38 #include "logging/log.hpp"
39 #include "memory/resourceArea.hpp"
40 #include "runtime/mutexLocker.hpp"
41 #include "runtime/orderAccess.inline.hpp"
42 #include "runtime/os.inline.hpp"
43 #include "runtime/safepoint.hpp"
44
45 typedef JfrCheckpointManager::Buffer* BufferPtr;
46
47 static JfrCheckpointManager* _instance = NULL;
48
49 JfrCheckpointManager& JfrCheckpointManager::instance() {
50 return *_instance;
51 }
52
53 JfrCheckpointManager* JfrCheckpointManager::create(JfrChunkWriter& cw) {
54 assert(_instance == NULL, "invariant");
55 _instance = new JfrCheckpointManager(cw);
56 return _instance;
57 }
58
59 void JfrCheckpointManager::destroy() {
60 assert(_instance != NULL, "invariant");
61 delete _instance;
62 _instance = NULL;
63 }
64
65 JfrCheckpointManager::JfrCheckpointManager(JfrChunkWriter& cw) :
66 _free_list_mspace(NULL),
67 _epoch_transition_mspace(NULL),
68 _lock(NULL),
69 _type_manager(NULL),
70 _service_thread(NULL),
71 _chunkwriter(cw),
72 _checkpoint_epoch_state(JfrTraceIdEpoch::epoch()) {}
73
74 JfrCheckpointManager::~JfrCheckpointManager() {
75 if (_free_list_mspace != NULL) {
76 delete _free_list_mspace;
77 }
78 if (_epoch_transition_mspace != NULL) {
79 delete _epoch_transition_mspace;
80 }
81 if (_lock != NULL) {
82 delete _lock;
83 }
84 if (_type_manager) {
85 delete _type_manager;
86 }
87 }
88
89 static const size_t unlimited_mspace_size = 0;
90 static const size_t checkpoint_buffer_cache_count = 2;
91 static const size_t checkpoint_buffer_size = 512 * K;
92
93 static JfrCheckpointMspace* create_mspace(size_t buffer_size, size_t limit, size_t cache_count, JfrCheckpointManager* system) {
94 JfrCheckpointMspace* mspace = new JfrCheckpointMspace(buffer_size, limit, cache_count, system);
95 if (mspace != NULL) {
96 mspace->initialize();
97 }
98 return mspace;
99 }
100
101 bool JfrCheckpointManager::initialize() {
102 assert(_free_list_mspace == NULL, "invariant");
103 _free_list_mspace = create_mspace(checkpoint_buffer_size, unlimited_mspace_size, checkpoint_buffer_cache_count, this);
104 if (_free_list_mspace == NULL) {
105 return false;
106 }
107 assert(_epoch_transition_mspace == NULL, "invariant");
108 _epoch_transition_mspace = create_mspace(checkpoint_buffer_size, unlimited_mspace_size, checkpoint_buffer_cache_count, this);
109 if (_epoch_transition_mspace == NULL) {
110 return false;
111 }
112 assert(_type_manager == NULL, "invariant");
113 _type_manager = new JfrTypeManager();
114 if (_type_manager == NULL || !_type_manager->initialize()) {
115 return false;
116 }
117 assert(_lock == NULL, "invariant");
118 _lock = new Mutex(Monitor::leaf - 1, "Checkpoint mutex", Mutex::_allow_vm_block_flag, Monitor::_safepoint_check_never);
119 return _lock != NULL;
120 }
121
122 bool JfrCheckpointManager::use_epoch_transition_mspace(const Thread* thread) const {
123 return _service_thread != thread && OrderAccess::load_acquire(&_checkpoint_epoch_state) != JfrTraceIdEpoch::epoch();
124 }
125
126 void JfrCheckpointManager::synchronize_epoch() {
127 assert(_checkpoint_epoch_state != JfrTraceIdEpoch::epoch(), "invariant");
128 OrderAccess::storestore();
129 _checkpoint_epoch_state = JfrTraceIdEpoch::epoch();
130 }
131
132 void JfrCheckpointManager::shift_epoch() {
133 debug_only(const u1 current_epoch = JfrTraceIdEpoch::current();)
134 JfrTraceIdEpoch::shift_epoch();
135 assert(current_epoch != JfrTraceIdEpoch::current(), "invariant");
136 }
137
138 void JfrCheckpointManager::register_service_thread(const Thread* thread) {
139 _service_thread = thread;
140 }
141
142 void JfrCheckpointManager::register_full(BufferPtr t, Thread* thread) {
143 // nothing here at the moment
144 assert(t->retired(), "invariant");
145 }
146
147 void JfrCheckpointManager::lock() {
148 assert(!_lock->owned_by_self(), "invariant");
149 _lock->lock_without_safepoint_check();
150 }
151
152 void JfrCheckpointManager::unlock() {
153 _lock->unlock();
154 }
155
156 #ifdef ASSERT
157
158 bool JfrCheckpointManager::is_locked() const {
159 return _lock->owned_by_self();
160 }
161
162 static void assert_free_lease(const BufferPtr buffer) {
163 assert(buffer != NULL, "invariant");
164 assert(buffer->acquired_by_self(), "invariant");
165 assert(buffer->lease(), "invariant");
166 }
167
168 static void assert_release(const BufferPtr buffer) {
169 assert(buffer != NULL, "invariant");
170 assert(buffer->lease(), "invariant");
171 assert(buffer->acquired_by_self(), "invariant");
172 }
173
174 #endif // ASSERT
175
176 static BufferPtr lease_free(size_t size, JfrCheckpointMspace* mspace, size_t retry_count, Thread* thread) {
177 static const size_t max_elem_size = mspace->min_elem_size(); // min is max
178 BufferPtr buffer;
179 if (size <= max_elem_size) {
180 BufferPtr buffer = mspace_get_free_lease_with_retry(size, mspace, retry_count, thread);
181 if (buffer != NULL) {
182 DEBUG_ONLY(assert_free_lease(buffer);)
183 return buffer;
184 }
185 }
186 buffer = mspace_allocate_transient_lease_to_free(size, mspace, thread);
187 DEBUG_ONLY(assert_free_lease(buffer);)
188 return buffer;
189 }
190
191 static const size_t lease_retry = 10;
192
193 BufferPtr JfrCheckpointManager::lease_buffer(Thread* thread, size_t size /* 0 */) {
194 JfrCheckpointManager& manager = instance();
195 if (manager.use_epoch_transition_mspace(thread)) {
196 return lease_free(size, manager._epoch_transition_mspace, lease_retry, thread);
197 }
198 return lease_free(size, manager._free_list_mspace, lease_retry, thread);
199 }
200
201 /*
202 * If the buffer was a "lease" from the free list, release back.
203 *
204 * The buffer is effectively invalidated for the thread post-return,
205 * and the caller should take means to ensure that it is not referenced.
206 */
207 static void release(BufferPtr const buffer, Thread* thread) {
208 DEBUG_ONLY(assert_release(buffer);)
209 buffer->clear_lease();
210 buffer->release();
211 }
212
213 BufferPtr JfrCheckpointManager::flush(BufferPtr old, size_t used, size_t requested, Thread* thread) {
214 assert(old != NULL, "invariant");
215 assert(old->lease(), "invariant");
216 if (0 == requested) {
217 // indicates a lease is being returned
218 release(old, thread);
219 return NULL;
220 }
221 // migration of in-flight information
222 BufferPtr const new_buffer = lease_buffer(thread, used + requested);
223 if (new_buffer != NULL) {
224 migrate_outstanding_writes(old, new_buffer, used, requested);
225 }
226 release(old, thread);
227 return new_buffer; // might be NULL
228 }
229
230 // offsets into the JfrCheckpointEntry
231 static const juint starttime_offset = sizeof(jlong);
232 static const juint duration_offset = starttime_offset + sizeof(jlong);
233 static const juint flushpoint_offset = duration_offset + sizeof(jlong);
234 static const juint types_offset = flushpoint_offset + sizeof(juint);
235 static const juint payload_offset = types_offset + sizeof(juint);
236
237 template <typename Return>
238 static Return read_data(const u1* data) {
239 return JfrBigEndian::read<Return>(data);
240 }
241
242 static jlong total_size(const u1* data) {
243 return read_data<jlong>(data);
244 }
245
246 static jlong starttime(const u1* data) {
247 return read_data<jlong>(data + starttime_offset);
248 }
249
250 static jlong duration(const u1* data) {
251 return read_data<jlong>(data + duration_offset);
252 }
253
254 static bool is_flushpoint(const u1* data) {
255 return read_data<juint>(data + flushpoint_offset) == (juint)1;
256 }
257
258 static juint number_of_types(const u1* data) {
259 return read_data<juint>(data + types_offset);
260 }
261
262 static void write_checkpoint_header(JfrChunkWriter& cw, intptr_t offset_prev_cp_event, const u1* data) {
263 cw.reserve(sizeof(u4));
264 cw.write((u8)EVENT_CHECKPOINT);
265 cw.write(starttime(data));
266 cw.write(duration(data));
267 cw.write((jlong)offset_prev_cp_event);
268 cw.write(is_flushpoint(data));
269 cw.write(number_of_types(data));
270 }
271
272 static void write_checkpoint_content(JfrChunkWriter& cw, const u1* data, size_t size) {
273 assert(data != NULL, "invariant");
274 cw.write_unbuffered(data + payload_offset, size);
275 }
276
277 static size_t write_checkpoint_event(JfrChunkWriter& cw, const u1* data) {
278 assert(data != NULL, "invariant");
279 const intptr_t previous_checkpoint_event = cw.previous_checkpoint_offset();
280 const intptr_t event_begin = cw.current_offset();
281 const intptr_t offset_to_previous_checkpoint_event = 0 == previous_checkpoint_event ? 0 : previous_checkpoint_event - event_begin;
282 const jlong total_checkpoint_size = total_size(data);
283 write_checkpoint_header(cw, offset_to_previous_checkpoint_event, data);
284 write_checkpoint_content(cw, data, total_checkpoint_size - sizeof(JfrCheckpointEntry));
285 const jlong checkpoint_event_size = cw.current_offset() - event_begin;
286 cw.write_padded_at_offset<u4>(checkpoint_event_size, event_begin);
287 cw.set_previous_checkpoint_offset(event_begin);
288 return (size_t)total_checkpoint_size;
289 }
290
291 static size_t write_checkpoints(JfrChunkWriter& cw, const u1* data, size_t size) {
292 assert(cw.is_valid(), "invariant");
293 assert(data != NULL, "invariant");
294 assert(size > 0, "invariant");
295 const u1* const limit = data + size;
296 const u1* next_entry = data;
297 size_t processed = 0;
298 while (next_entry < limit) {
299 const size_t checkpoint_size = write_checkpoint_event(cw, next_entry);
300 processed += checkpoint_size;
301 next_entry += checkpoint_size;
302 }
303 assert(next_entry == limit, "invariant");
304 return processed;
305 }
306
307 template <typename T>
308 class CheckpointWriteOp {
309 private:
310 JfrChunkWriter& _writer;
311 size_t _processed;
312 public:
313 typedef T Type;
314 CheckpointWriteOp(JfrChunkWriter& writer) : _writer(writer), _processed(0) {}
315 bool write(Type* t, const u1* data, size_t size) {
316 _processed += write_checkpoints(_writer, data, size);
317 return true;
318 }
319 size_t processed() const { return _processed; }
320 };
321
322 typedef CheckpointWriteOp<JfrCheckpointMspace::Type> WriteOperation;
323 typedef MutexedWriteOp<WriteOperation> MutexedWriteOperation;
324 typedef ReleaseOp<JfrCheckpointMspace> CheckpointReleaseOperation;
325 typedef CompositeOperation<MutexedWriteOperation, CheckpointReleaseOperation> CheckpointWriteOperation;
326
327 static size_t write_mspace_exclusive(JfrCheckpointMspace* mspace, JfrChunkWriter& chunkwriter) {
328 Thread* const thread = Thread::current();
329 WriteOperation wo(chunkwriter);
330 MutexedWriteOperation mwo(wo);
331 CheckpointReleaseOperation cro(mspace, thread, false);
332 CheckpointWriteOperation cpwo(&mwo, &cro);
333 assert(mspace->is_full_empty(), "invariant");
334 process_free_list(cpwo, mspace);
335 return wo.processed();
336 }
337
338 size_t JfrCheckpointManager::write() {
339 const size_t processed = write_mspace_exclusive(_free_list_mspace, _chunkwriter);
340 synchronize_epoch();
341 return processed;
342 }
343
344 size_t JfrCheckpointManager::write_epoch_transition_mspace() {
345 return write_mspace_exclusive(_epoch_transition_mspace, _chunkwriter);
346 }
347
348 typedef DiscardOp<DefaultDiscarder<JfrBuffer> > DiscardOperation;
349 size_t JfrCheckpointManager::clear() {
350 DiscardOperation discarder(mutexed); // mutexed discard mode
351 process_free_list(discarder, _free_list_mspace);
352 process_free_list(discarder, _epoch_transition_mspace);
353 synchronize_epoch();
354 return discarder.processed();
355 }
356
357 bool JfrCheckpointManager::register_serializer(JfrTypeId id, bool require_safepoint, bool permit_cache, JfrSerializer* cs) {
358 assert(cs != NULL, "invariant");
359 return instance()._type_manager->register_serializer(id, require_safepoint, permit_cache, cs);
360 }
361
362 size_t JfrCheckpointManager::write_types() {
363 JfrCheckpointWriter writer(false, true, Thread::current());
364 _type_manager->write_types(writer);
365 return writer.used_size();
366 }
367
368 size_t JfrCheckpointManager::write_safepoint_types() {
369 // this is also a "flushpoint"
370 JfrCheckpointWriter writer(true, true, Thread::current());
371 _type_manager->write_safepoint_types(writer);
372 return writer.used_size();
373 }
374
375 void JfrCheckpointManager::write_type_set() {
376 _type_manager->write_type_set();
377 }
378
379 void JfrCheckpointManager::write_type_set_for_unloaded_classes() {
380 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
381 instance()._type_manager->write_type_set_for_unloaded_classes();
382 }
383
384 void JfrCheckpointManager::create_thread_checkpoint(JavaThread* jt) {
385 instance()._type_manager->create_thread_checkpoint(jt);
386 }
387
388 void JfrCheckpointManager::write_thread_checkpoint(JavaThread* jt) {
389 instance()._type_manager->write_thread_checkpoint(jt);
390 }