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.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
45typedef JfrCheckpointManager::Buffer* BufferPtr;
46
47static JfrCheckpointManager* _instance = NULL;
48
49JfrCheckpointManager& JfrCheckpointManager::instance() {
50 return *_instance;
51}
52
53JfrCheckpointManager* JfrCheckpointManager::create(JfrChunkWriter& cw) {
54 assert(_instance == NULL, "invariant");
55 _instance = new JfrCheckpointManager(cw);
56 return _instance;
57}
58
59void JfrCheckpointManager::destroy() {
60 assert(_instance != NULL, "invariant");
61 delete _instance;
62 _instance = NULL;
63}
64
65JfrCheckpointManager::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
73JfrCheckpointManager::~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
86static const size_t unlimited_mspace_size = 0;
87static const size_t checkpoint_buffer_cache_count = 2;
88static const size_t checkpoint_buffer_size = 512 * K;
89
90static 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
98bool 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
117bool JfrCheckpointManager::use_epoch_transition_mspace(const Thread* thread) const {
118 return _service_thread != thread && OrderAccess::load_acquire(&_checkpoint_epoch_state) != JfrTraceIdEpoch::epoch();
119}
120
121void JfrCheckpointManager::synchronize_epoch() {
122 assert(_checkpoint_epoch_state != JfrTraceIdEpoch::epoch(), "invariant");
123 OrderAccess::storestore();
124 _checkpoint_epoch_state = JfrTraceIdEpoch::epoch();
125}
126
127void 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
133void JfrCheckpointManager::register_service_thread(const Thread* thread) {
134 _service_thread = thread;
135}
136
137void JfrCheckpointManager::register_full(BufferPtr t, Thread* thread) {
138 // nothing here at the moment
139 assert(t != NULL, "invariant");
140 assert(t->acquired_by(thread), "invariant");
141 assert(t->retired(), "invariant");
142}
143
144void JfrCheckpointManager::lock() {
145 assert(!_lock->owned_by_self(), "invariant");
146 _lock->lock_without_safepoint_check();
147}
148
149void JfrCheckpointManager::unlock() {
150 _lock->unlock();
151}
152
153#ifdef ASSERT
154
155bool JfrCheckpointManager::is_locked() const {
156 return _lock->owned_by_self();
157}
158
159static void assert_free_lease(const BufferPtr buffer) {
160 assert(buffer != NULL, "invariant");
161 assert(buffer->acquired_by_self(), "invariant");
162 assert(buffer->lease(), "invariant");
163}
164
165static void assert_release(const BufferPtr buffer) {
166 assert(buffer != NULL, "invariant");
167 assert(buffer->lease(), "invariant");
168 assert(buffer->acquired_by_self(), "invariant");
169}
170
171#endif // ASSERT
172
173static BufferPtr lease_free(size_t size, JfrCheckpointMspace* mspace, size_t retry_count, Thread* thread) {
174 static const size_t max_elem_size = mspace->min_elem_size(); // min is max
175 BufferPtr buffer;
176 if (size <= max_elem_size) {
177 BufferPtr buffer = mspace_get_free_lease_with_retry(size, mspace, retry_count, thread);
178 if (buffer != NULL) {
179 DEBUG_ONLY(assert_free_lease(buffer);)
180 return buffer;
181 }
182 }
183 buffer = mspace_allocate_transient_lease_to_free(size, mspace, thread);
184 DEBUG_ONLY(assert_free_lease(buffer);)
185 return buffer;
186}
187
188static const size_t lease_retry = 10;
189
190BufferPtr JfrCheckpointManager::lease_buffer(Thread* thread, size_t size /* 0 */) {
191 JfrCheckpointManager& manager = instance();
192 if (manager.use_epoch_transition_mspace(thread)) {
193 return lease_free(size, manager._epoch_transition_mspace, lease_retry, thread);
194 }
195 return lease_free(size, manager._free_list_mspace, lease_retry, thread);
196}
197
198/*
199* If the buffer was a "lease" from the free list, release back.
200*
201* The buffer is effectively invalidated for the thread post-return,
202* and the caller should take means to ensure that it is not referenced.
203*/
204static void release(BufferPtr const buffer, Thread* thread) {
205 DEBUG_ONLY(assert_release(buffer);)
206 buffer->clear_lease();
207 buffer->release();
208}
209
210BufferPtr JfrCheckpointManager::flush(BufferPtr old, size_t used, size_t requested, Thread* thread) {
211 assert(old != NULL, "invariant");
212 assert(old->lease(), "invariant");
213 if (0 == requested) {
214 // indicates a lease is being returned
215 release(old, thread);
216 return NULL;
217 }
218 // migration of in-flight information
219 BufferPtr const new_buffer = lease_buffer(thread, used + requested);
220 if (new_buffer != NULL) {
221 migrate_outstanding_writes(old, new_buffer, used, requested);
222 }
223 release(old, thread);
224 return new_buffer; // might be NULL
225}
226
227// offsets into the JfrCheckpointEntry
228static const juint starttime_offset = sizeof(jlong);
229static const juint duration_offset = starttime_offset + sizeof(jlong);
230static const juint flushpoint_offset = duration_offset + sizeof(jlong);
231static const juint types_offset = flushpoint_offset + sizeof(juint);
232static const juint payload_offset = types_offset + sizeof(juint);
233
234template <typename Return>
235static Return read_data(const u1* data) {
236 return JfrBigEndian::read<Return>(data);
237}
238
239static jlong total_size(const u1* data) {
240 return read_data<jlong>(data);
241}
242
243static jlong starttime(const u1* data) {
244 return read_data<jlong>(data + starttime_offset);
245}
246
247static jlong duration(const u1* data) {
248 return read_data<jlong>(data + duration_offset);
249}
250
251static bool is_flushpoint(const u1* data) {
252 return read_data<juint>(data + flushpoint_offset) == (juint)1;
253}
254
255static juint number_of_types(const u1* data) {
256 return read_data<juint>(data + types_offset);
257}
258
259static void write_checkpoint_header(JfrChunkWriter& cw, intptr_t offset_prev_cp_event, const u1* data) {
260 cw.reserve(sizeof(u4));
261 cw.write((u8)EVENT_CHECKPOINT);
262 cw.write(starttime(data));
263 cw.write(duration(data));
264 cw.write((jlong)offset_prev_cp_event);
265 cw.write(is_flushpoint(data));
266 cw.write(number_of_types(data));
267}
268
269static void write_checkpoint_content(JfrChunkWriter& cw, const u1* data, size_t size) {
270 assert(data != NULL, "invariant");
271 cw.write_unbuffered(data + payload_offset, size);
272}
273
274static size_t write_checkpoint_event(JfrChunkWriter& cw, const u1* data) {
275 assert(data != NULL, "invariant");
276 const intptr_t previous_checkpoint_event = cw.previous_checkpoint_offset();
277 const intptr_t event_begin = cw.current_offset();
278 const intptr_t offset_to_previous_checkpoint_event = 0 == previous_checkpoint_event ? 0 : previous_checkpoint_event - event_begin;
279 const jlong total_checkpoint_size = total_size(data);
280 write_checkpoint_header(cw, offset_to_previous_checkpoint_event, data);
281 write_checkpoint_content(cw, data, total_checkpoint_size - sizeof(JfrCheckpointEntry));
282 const jlong checkpoint_event_size = cw.current_offset() - event_begin;
283 cw.write_padded_at_offset<u4>(checkpoint_event_size, event_begin);
284 cw.set_previous_checkpoint_offset(event_begin);
285 return (size_t)total_checkpoint_size;
286}
287
288static size_t write_checkpoints(JfrChunkWriter& cw, const u1* data, size_t size) {
289 assert(cw.is_valid(), "invariant");
290 assert(data != NULL, "invariant");
291 assert(size > 0, "invariant");
292 const u1* const limit = data + size;
293 const u1* next_entry = data;
294 size_t processed = 0;
295 while (next_entry < limit) {
296 const size_t checkpoint_size = write_checkpoint_event(cw, next_entry);
297 processed += checkpoint_size;
298 next_entry += checkpoint_size;
299 }
300 assert(next_entry == limit, "invariant");
301 return processed;
302}
303
304template <typename T>
305class CheckpointWriteOp {
306 private:
307 JfrChunkWriter& _writer;
308 size_t _processed;
309 public:
310 typedef T Type;
311 CheckpointWriteOp(JfrChunkWriter& writer) : _writer(writer), _processed(0) {}
312 bool write(Type* t, const u1* data, size_t size) {
313 _processed += write_checkpoints(_writer, data, size);
314 return true;
315 }
316 size_t processed() const { return _processed; }
317};
318
319typedef CheckpointWriteOp<JfrCheckpointMspace::Type> WriteOperation;
320typedef MutexedWriteOp<WriteOperation> MutexedWriteOperation;
321typedef ReleaseOp<JfrCheckpointMspace> CheckpointReleaseOperation;
322typedef CompositeOperation<MutexedWriteOperation, CheckpointReleaseOperation> CheckpointWriteOperation;
323
324static size_t write_mspace_exclusive(JfrCheckpointMspace* mspace, JfrChunkWriter& chunkwriter) {
325 Thread* const thread = Thread::current();
326 WriteOperation wo(chunkwriter);
327 MutexedWriteOperation mwo(wo);
328 CheckpointReleaseOperation cro(mspace, thread, false);
329 CheckpointWriteOperation cpwo(&mwo, &cro);
330 assert(mspace->is_full_empty(), "invariant");
331 process_free_list(cpwo, mspace);
332 return wo.processed();
333}
334
335size_t JfrCheckpointManager::write() {
336 const size_t processed = write_mspace_exclusive(_free_list_mspace, _chunkwriter);
337 synchronize_epoch();
338 return processed;
339}
340
341size_t JfrCheckpointManager::write_epoch_transition_mspace() {
342 return write_mspace_exclusive(_epoch_transition_mspace, _chunkwriter);
343}
344
345typedef DiscardOp<DefaultDiscarder<JfrBuffer> > DiscardOperation;
346size_t JfrCheckpointManager::clear() {
347 DiscardOperation discarder(mutexed); // mutexed discard mode
348 process_free_list(discarder, _free_list_mspace);
349 process_free_list(discarder, _epoch_transition_mspace);
350 synchronize_epoch();
351 return discarder.processed();
352}
353
354size_t JfrCheckpointManager::write_types() {
355 JfrCheckpointWriter writer(false, true, Thread::current());
356 JfrTypeManager::write_types(writer);
357 return writer.used_size();
358}
359
360size_t JfrCheckpointManager::write_safepoint_types() {
361 // this is also a "flushpoint"
362 JfrCheckpointWriter writer(true, true, Thread::current());
363 JfrTypeManager::write_safepoint_types(writer);
364 return writer.used_size();
365}
366
367void JfrCheckpointManager::write_type_set() {
368 JfrTypeManager::write_type_set();
369}
370
371void JfrCheckpointManager::write_type_set_for_unloaded_classes() {
372 assert_locked_or_safepoint(ClassLoaderDataGraph_lock);
373 JfrTypeManager::write_type_set_for_unloaded_classes();
374}
375
376void JfrCheckpointManager::create_thread_checkpoint(JavaThread* jt) {
377 JfrTypeManager::create_thread_checkpoint(jt);
378}
379
380void JfrCheckpointManager::write_thread_checkpoint(JavaThread* jt) {
381 JfrTypeManager::write_thread_checkpoint(jt);
382}
383