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/jfrRecorder.hpp"
28 #include "jfr/recorder/access/jfrbackend.hpp"
29 #include "jfr/recorder/access/jfrOptionSet.hpp"
30 #include "jfr/recorder/checkpoint/jfrCheckpointManager.hpp"
31 #include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"
32 #include "jfr/recorder/checkpoint/constant/jfrConstantManager.hpp"
33 #include "jfr/recorder/checkpoint/constant/traceid/jfrTraceIdEpoch.hpp"
34 #include "jfr/recorder/storage/jfrMemorySpace.inline.hpp"
35 #include "jfr/recorder/storage/jfrStorageUtils.inline.hpp"
36 #include "jfr/recorder/repository/jfrChunkWriter.hpp"
37 #include "jfr/utilities/jfrBigEndian.hpp"
38 #include "jfr/utilities/jfrLog.hpp"
39 #include "memory/resourceArea.hpp"
40 #include "runtime/mutexLocker.hpp"
41 #include "runtime/orderAccess.inline.hpp"
42 #include "runtime/safepoint.hpp"
43 #include "tracefiles/traceTypes.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 _epoch_transition_list(),
67 _free_list_mspace(NULL),
68 _transient_mspace(NULL),
69 _lock(NULL),
70 _constant_manager(NULL),
71 _service_thread(NULL),
72 _chunkwriter(cw),
73 _checkpoint_epoch_state(JfrTraceIdEpoch::epoch()) {}
74
75 JfrCheckpointManager::~JfrCheckpointManager() {
76 if (_free_list_mspace != NULL) {
77 delete _free_list_mspace;
78 }
79 if (_transient_mspace != NULL) {
80 delete _transient_mspace;
81 }
82 if (_lock != NULL) {
83 delete _lock;
84 }
85 if (_constant_manager) {
86 delete _constant_manager;
87 }
88 assert(_epoch_transition_list.count() == 0, "invariant");
89 }
90
91 static const size_t unlimited_mspace_size = 0;
92 static const size_t checkpoint_buffer_cache_count = 2;
93 static const size_t checkpoint_buffer_size = M;
94 static const size_t limited_mspace_size = checkpoint_buffer_cache_count * checkpoint_buffer_size;
95
96 static JfrCheckpointMspace* create_mspace(size_t buffer_size, size_t limit, size_t cache_count, JfrCheckpointManager* system) {
97 JfrCheckpointMspace* mspace = new JfrCheckpointMspace(buffer_size, limit, cache_count, system);
98 if (mspace != NULL) {
99 mspace->initialize();
100 }
101 return mspace;
102 }
103
104 bool JfrCheckpointManager::initialize() {
105 assert(_free_list_mspace == NULL, "invariant");
106 _free_list_mspace = create_mspace(checkpoint_buffer_size, limited_mspace_size, checkpoint_buffer_cache_count, this);
107 if (_free_list_mspace == NULL) {
108 return false;
109 }
110 assert(_transient_mspace == NULL, "invariant");
111 _transient_mspace = create_mspace((size_t)JfrOptionSet::global_buffer_size(), unlimited_mspace_size, 0, this);
112 if (_transient_mspace == NULL) {
113 return false;
114 }
115 assert(_constant_manager == NULL, "invariant");
116 _constant_manager = new JfrConstantManager();
117 if (_constant_manager == NULL || !_constant_manager->initialize()) {
118 return false;
119 }
120 assert(_lock == NULL, "invariant");
121 _lock = new Mutex(Monitor::leaf - 1, "Checkpoint mutex", Mutex::_allow_vm_block_flag);
122 return _lock != NULL;
123 }
124
125 bool JfrCheckpointManager::use_epoch_transition_list(const Thread* thread) const {
126 return _service_thread != thread && OrderAccess::load_acquire(&_checkpoint_epoch_state) != JfrTraceIdEpoch::epoch();
127 }
128
129 void JfrCheckpointManager::synchronize_epoch() {
130 assert(_checkpoint_epoch_state != JfrTraceIdEpoch::epoch(), "invariant");
131 OrderAccess::storestore();
132 _checkpoint_epoch_state = JfrTraceIdEpoch::epoch();
133 }
134
135 void JfrCheckpointManager::register_service_thread(const Thread* thread) {
136 _service_thread = thread;
137 }
138
139 void JfrCheckpointManager::register_full(BufferPtr t, Thread* thread) {
140 // nothing here at the moment
141 assert(t->retired(), "invariant");
142 }
143
144 void JfrCheckpointManager::lock() {
145 assert(!_lock->owned_by_self(), "invariant");
146 _lock->lock_without_safepoint_check();
147 }
148
149 void JfrCheckpointManager::unlock() {
150 _lock->unlock();
151 }
152
153 void JfrCheckpointManager::shift_epoch() {
154 debug_only(const u1 current_epoch = JfrTraceIdEpoch::current();)
155 JfrTraceIdEpoch::shift_epoch();
156 assert(current_epoch != JfrTraceIdEpoch::current(), "invariant");
157 }
158
159 #ifdef ASSERT
160 static void assert_free_lease(const BufferPtr buffer) {
161 assert(buffer != NULL, "invariant");
162 assert(buffer->acquired_by_self(), "invariant");
163 assert(!buffer->transient(), "invariant");
164 assert(buffer->lease(), "invariant");
165 }
166
167 static void assert_transient_lease(const BufferPtr buffer) {
168 assert(buffer->acquired_by_self(), "invariant");
169 assert(buffer->transient(), "invariant");
170 assert(buffer->lease(), "invariant");
171 }
172
173 static void assert_release(const BufferPtr buffer) {
174 assert(buffer != NULL, "invariant");
175 assert(buffer->lease(), "invariant");
176 assert(buffer->acquired_by_self(), "invariant");
177 }
178
179 #endif // ASSERT
180
181 static const size_t lease_retry = 10;
182
183 static BufferPtr lease_free(size_t size, JfrCheckpointMspace* mspace, Thread* thread) {
184 return mspace_get_free_lease_with_retry(size, mspace, lease_retry, thread);
185 }
186
187 BufferPtr JfrCheckpointManager::lease_buffer(Thread* thread, size_t size /* 0 */) {
188 if (instance().use_epoch_transition_list(thread)) {
189 // epoch has changed
190 return instance().lease_transient(size, thread);
191 }
192 static const size_t max_elem_size = instance()._free_list_mspace->min_elem_size(); // min is max
193 if (size <= max_elem_size) {
194 BufferPtr const buffer = lease_free(size, instance()._free_list_mspace, thread);
195 if (buffer != NULL) {
196 DEBUG_ONLY(assert_free_lease(buffer);)
197 return buffer;
198 }
199 }
200 return instance().lease_transient(size, thread);
201 }
202
203 /*
204 * 1. If the buffer was a "lease" from the free list, release back.
205 * 2. If the buffer is transient (temporal dynamically allocated), retire and release.
206 *
207 * The buffer is effectively invalidated for the thread post-return,
208 * and the caller should take means to ensure that it is not referenced.
209 */
210 static void release(BufferPtr const buffer, Thread* thread) {
211 DEBUG_ONLY(assert_release(buffer);)
212 buffer->clear_lease();
213 if (buffer->transient()) {
214 buffer->set_retired();
215 } else {
216 buffer->release();
217 }
218 }
219
220 BufferPtr JfrCheckpointManager::flush(BufferPtr old, size_t used, size_t requested, Thread* thread) {
221 assert(old != NULL, "invariant");
222 assert(old->lease(), "invariant");
223 if (0 == requested) {
224 // indicates a lease is being returned
225 release(old, thread);
226 return NULL;
227 }
228 // migration of in-flight information
229 BufferPtr const new_buffer = lease_buffer(thread, used + requested);
230 if (new_buffer != NULL) {
231 migrate_outstanding_writes(old, new_buffer, used, requested);
232 }
233 release(old, thread);
234 return new_buffer; // might be NULL
235 }
236
237 BufferPtr JfrCheckpointManager::lease_transient(size_t size, Thread* thread) {
238 BufferPtr buffer = mspace_allocate_transient_lease(size, _transient_mspace, thread);
239 if (buffer == NULL) {
240 log_warning(jfr)("Unable to allocate " SIZE_FORMAT " bytes of transient memory.", size);
241 return NULL;
242 }
243 DEBUG_ONLY(assert_transient_lease(buffer);)
244 MutexLockerEx lock(_lock, Mutex::_no_safepoint_check_flag);
245 if (use_epoch_transition_list(thread)) {
246 _epoch_transition_list.append(buffer);
247 } else {
248 _transient_mspace->insert_full_tail(buffer);
249 }
250 return buffer;
251 }
252
253 template <typename Processor>
254 static void process_epoch_transition_list(Processor& processor, JfrCheckpointMspace* mspace, JfrCheckpointMspace::List& list) {
255 assert(mspace != NULL, "invariant");
256 assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
257 if (list.count() == 0) {
258 // nothing to do
259 return;
260 }
261 // Fetch epoch transition list nodes.
262 // No inserts will happen concurrently so we are ok outside the lock
263 JfrCheckpointMspace::Type* buffer = list.clear();
264 assert(list.count() == 0, "invariant");
265 while (buffer != NULL) {
266 assert(buffer->retired(), "invariant");
267 assert(buffer->transient(), "invariant");
268 JfrCheckpointMspace::Type* next = buffer->next();
269 processor.process(buffer);
270 mspace->deallocate(buffer);
271 buffer = next;
272 }
273 }
274
275 // offsets into the JfrCheckpointEntry
276 static const juint starttime_offset = sizeof(jlong);
277 static const juint duration_offset = starttime_offset + sizeof(jlong);
278 static const juint flushpoint_offset = duration_offset + sizeof(jlong);
279 static const juint constant_types_offset = flushpoint_offset + sizeof(juint);
280 static const juint payload_offset = constant_types_offset + sizeof(juint);
281
282 template <typename Return>
283 static Return read_data(const u1* data) {
284 return JfrBigEndian::read<Return>(data);
285 }
286
287 static jlong total_size(const u1* data) {
288 return read_data<jlong>(data);
289 }
290
291 static jlong starttime(const u1* data) {
292 return read_data<jlong>(data + starttime_offset);
293 }
294
295 static jlong duration(const u1* data) {
296 return read_data<jlong>(data + duration_offset);
297 }
298
299 static bool is_flushpoint(const u1* data) {
300 return read_data<juint>(data + flushpoint_offset) == (juint)1;
301 }
302
303 static juint number_of_constant_types(const u1* data) {
304 return read_data<juint>(data + constant_types_offset);
305 }
306
307 static void write_checkpoint_header(JfrChunkWriter& cw, intptr_t offset_prev_cp_event, const u1* data) {
308 cw.reserve(sizeof(u4));
309 cw.write((u8)EVENT_CHECKPOINT);
310 cw.write(starttime(data));
311 cw.write(duration(data));
312 cw.write((jlong)offset_prev_cp_event);
313 cw.write(is_flushpoint(data));
314 cw.write(number_of_constant_types(data));
315 }
316
317 static void write_checkpoint_content(JfrChunkWriter& cw, const u1* data, size_t size) {
318 assert(data != NULL, "invariant");
319 cw.write_unbuffered(data + payload_offset, size);
320 }
321
322 static size_t write_checkpoint_event(JfrChunkWriter& cw, const u1* data) {
323 assert(data != NULL, "invariant");
324 const intptr_t previous_checkpoint_event = cw.previous_checkpoint_offset();
325 const intptr_t event_begin = cw.current_offset();
326 const intptr_t offset_to_previous_checkpoint_event = 0 == previous_checkpoint_event ? 0 : previous_checkpoint_event - event_begin;
327 const jlong total_checkpoint_size = total_size(data);
328 write_checkpoint_header(cw, offset_to_previous_checkpoint_event, data);
329 write_checkpoint_content(cw, data, total_checkpoint_size - sizeof(JfrCheckpointEntry));
330 const jlong checkpoint_event_size = cw.current_offset() - event_begin;
331 cw.write_padded_at_offset<u4>(checkpoint_event_size, event_begin);
332 cw.set_previous_checkpoint_offset(event_begin);
333 return (size_t)total_checkpoint_size;
334 }
335
336 static size_t write_checkpoints(JfrChunkWriter& cw, const u1* data, size_t size) {
337 assert(cw.is_valid(), "invariant");
338 assert(data != NULL, "invariant");
339 assert(size > 0, "invariant");
340 const u1* const limit = data + size;
341 const u1* next_entry = data;
342 size_t processed = 0;
343 while (next_entry < limit) {
344 const size_t checkpoint_size = write_checkpoint_event(cw, next_entry);
345 processed += checkpoint_size;
346 next_entry += checkpoint_size;
347 }
348 assert(next_entry == limit, "invariant");
349 return processed;
350 }
351
352 template <typename T>
353 class CheckpointWriteOp {
354 private:
355 JfrChunkWriter& _writer;
356 size_t _processed;
357 public:
358 typedef T Type;
359 CheckpointWriteOp(JfrChunkWriter& writer) : _writer(writer), _processed(0) {}
360 bool write(Type* t, const u1* data, size_t size) {
361 _processed += write_checkpoints(_writer, data, size);
362 return true;
363 }
364 size_t processed() const { return _processed; }
365 };
366
367 typedef CheckpointWriteOp<JfrCheckpointMspace::Type> WriteOperation;
368 typedef ConcurrentWriteOp<WriteOperation> ConcurrentWriteOperation;
369 typedef MutexedReleaseOp<JfrCheckpointMspace> CheckpointReleaseOperation;
370 typedef CompositeOperation<ConcurrentWriteOperation, CheckpointReleaseOperation> CheckpointWriteOperation;
371
372 size_t JfrCheckpointManager::write() {
373 Thread* const thread = Thread::current();
374 WriteOperation wo(_chunkwriter);
375 ConcurrentWriteOperation cwo(wo);
376 CheckpointReleaseOperation cro(_free_list_mspace, thread);
377 CheckpointWriteOperation cpwo(&cwo, &cro);
378 assert(_free_list_mspace->is_full_empty(), "invariant");
379 process_free_list(cpwo, _free_list_mspace);
380 CheckpointReleaseOperation transient_release(_transient_mspace, thread);
381 CheckpointWriteOperation transient_writer(&cwo, &transient_release);
382 assert(_transient_mspace->is_free_empty(), "invariant");
383 process_full_list(transient_writer, _transient_mspace);
384 synchronize_epoch();
385 return wo.processed();
386 }
387
388 typedef MutexedWriteOp<WriteOperation> MutexedWriteOperation;
389
390 size_t JfrCheckpointManager::write_epoch_transition_list() {
391 WriteOperation wo(_chunkwriter);
392 MutexedWriteOperation epoch_list_writer(wo); // mutexed write mode
393 process_epoch_transition_list(epoch_list_writer, _transient_mspace, _epoch_transition_list);
394 return epoch_list_writer.processed();
395 }
396
397 typedef DiscardOp<DefaultDiscarder<JfrBuffer> > DiscardOperation;
398 size_t JfrCheckpointManager::clear() {
399 DiscardOperation discarder(concurrent); // concurrent discard mode
400 process_full_list(discarder, _transient_mspace);
401 process_epoch_transition_list(discarder, _transient_mspace, _epoch_transition_list);
402 process_free_list(discarder, _free_list_mspace);
403 synchronize_epoch();
404 return discarder.processed();
405 }
406
407 bool JfrCheckpointManager::register_serializer(JfrConstantTypeId id, bool require_safepoint, bool permit_cache, JfrConstantSerializer* cs) {
408 assert(cs != NULL, "invariant");
409 return instance()._constant_manager->register_serializer(id, require_safepoint, permit_cache, cs);
410 }
411
412 size_t JfrCheckpointManager::write_constant_types() {
413 JfrCheckpointWriter writer(false, true, Thread::current());
414 _constant_manager->write_constants(writer);
415 return writer.used_size();
416 }
417
418 size_t JfrCheckpointManager::write_safepoint_constant_types() {
419 // this is also a "flushpoint"
420 JfrCheckpointWriter writer(true, true, Thread::current());
421 _constant_manager->write_safepoint_constants(writer);
422 return writer.used_size();
423 }
424
425 void JfrCheckpointManager::write_constant_tag_set() {
426 _constant_manager->write_constant_tag_set();
427 }
428
429 void JfrCheckpointManager::write_constant_tag_set_for_unloaded_classes() {
430 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
431 instance()._constant_manager->write_constant_tag_set_for_unloaded_classes();
432 }
433
434 void JfrCheckpointManager::create_thread_checkpoint(JavaThread* jt) {
435 instance()._constant_manager->create_thread_checkpoint(jt);
436 }
437
438 void JfrCheckpointManager::write_thread_checkpoint(JavaThread* jt) {
439 instance()._constant_manager->write_thread_checkpoint(jt);
440 }