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