0 /*
1  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3  *
4  * This code is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License version 2 only, as
6  * published by the Free Software Foundation.
7  *
8  * This code is distributed in the hope that it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
11  * version 2 for more details (a copy is included in the LICENSE file that
12  * accompanied this code).
13  *
14  * You should have received a copy of the GNU General Public License version
15  * 2 along with this work; if not, write to the Free Software Foundation,
16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17  *
18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19  * or visit www.oracle.com if you need additional information or have any
20  * questions.
21  *
22  */
23 
24 #include "precompiled.hpp"
25 #include "classfile/javaClasses.inline.hpp"
26 #include "jfr/recorder/jfrRecorder.hpp"
27 #include "jfr/recorder/checkpoint/jfrCheckpointManager.hpp"
28 #include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"
29 #include "jfr/recorder/checkpoint/types/jfrTypeManager.hpp"
30 #include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
31 #include "jfr/recorder/service/jfrOptionSet.hpp"
32 #include "jfr/recorder/storage/jfrMemorySpace.inline.hpp"
33 #include "jfr/recorder/storage/jfrStorageUtils.inline.hpp"
34 #include "jfr/recorder/repository/jfrChunkWriter.hpp"
35 #include "jfr/utilities/jfrBigEndian.hpp"
36 #include "jfr/utilities/jfrTypes.hpp"
37 #include "logging/log.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "runtime/mutexLocker.hpp"
40 #include "runtime/orderAccess.hpp"
41 #include "runtime/os.inline.hpp"
42 #include "runtime/safepoint.hpp"
43 
44 typedef JfrCheckpointManager::Buffer* BufferPtr;
45 
46 static JfrCheckpointManager* _instance = NULL;
47 
48 JfrCheckpointManager& JfrCheckpointManager::instance() {
49   return *_instance;
50 }
51 
52 JfrCheckpointManager* JfrCheckpointManager::create(JfrChunkWriter& cw) {
53   assert(_instance == NULL, "invariant");
54   _instance = new JfrCheckpointManager(cw);
55   return _instance;
56 }
57 
58 void JfrCheckpointManager::destroy() {
59   assert(_instance != NULL, "invariant");
60   delete _instance;
61   _instance = NULL;
62 }
63 
64 JfrCheckpointManager::JfrCheckpointManager(JfrChunkWriter& cw) :
65   _free_list_mspace(NULL),
66   _epoch_transition_mspace(NULL),
67   _lock(NULL),
68   _service_thread(NULL),
69   _chunkwriter(cw),
70   _checkpoint_epoch_state(JfrTraceIdEpoch::epoch()) {}
71 
72 JfrCheckpointManager::~JfrCheckpointManager() {
73   if (_free_list_mspace != NULL) {
74     delete _free_list_mspace;
75   }
76   if (_epoch_transition_mspace != NULL) {
77     delete _epoch_transition_mspace;
78   }
79   if (_lock != NULL) {
80     delete _lock;
81   }
82   JfrTypeManager::clear();
83 }
84 
85 static const size_t unlimited_mspace_size = 0;
86 static const size_t checkpoint_buffer_cache_count = 2;
87 static const size_t checkpoint_buffer_size = 512 * K;
88 
89 static JfrCheckpointMspace* create_mspace(size_t buffer_size, size_t limit, size_t cache_count, JfrCheckpointManager* system) {
90   JfrCheckpointMspace* mspace = new JfrCheckpointMspace(buffer_size, limit, cache_count, system);
91   if (mspace != NULL) {
92     mspace->initialize();
93   }
94   return mspace;
95 }
96 
97 bool JfrCheckpointManager::initialize() {
98   assert(_free_list_mspace == NULL, "invariant");
99   _free_list_mspace = create_mspace(checkpoint_buffer_size, unlimited_mspace_size, checkpoint_buffer_cache_count, this);
100   if (_free_list_mspace == NULL) {
101     return false;
102   }
103   assert(_epoch_transition_mspace == NULL, "invariant");
104   _epoch_transition_mspace = create_mspace(checkpoint_buffer_size, unlimited_mspace_size, checkpoint_buffer_cache_count, this);
105   if (_epoch_transition_mspace == NULL) {
106     return false;
107   }
108   assert(_lock == NULL, "invariant");
109   _lock = new Mutex(Monitor::leaf - 1, "Checkpoint mutex", Mutex::_allow_vm_block_flag, Monitor::_safepoint_check_never);
110   if (_lock == NULL) {
111     return false;
112   }
113   return JfrTypeManager::initialize();
114 }
115 
116 bool JfrCheckpointManager::use_epoch_transition_mspace(const Thread* thread) const {
117   return _service_thread != thread && OrderAccess::load_acquire(&_checkpoint_epoch_state) != JfrTraceIdEpoch::epoch();
118 }
119 
120 void JfrCheckpointManager::synchronize_epoch() {
121   assert(_checkpoint_epoch_state != JfrTraceIdEpoch::epoch(), "invariant");
122   OrderAccess::storestore();
123   _checkpoint_epoch_state = JfrTraceIdEpoch::epoch();
124 }
125 
126 void JfrCheckpointManager::shift_epoch() {
127   debug_only(const u1 current_epoch = JfrTraceIdEpoch::current();)
128   JfrTraceIdEpoch::shift_epoch();
129   assert(current_epoch != JfrTraceIdEpoch::current(), "invariant");
130 }
131 
132 void JfrCheckpointManager::register_service_thread(const Thread* thread) {
133   _service_thread = thread;
134 }
135 
136 void JfrCheckpointManager::register_full(BufferPtr t, Thread* thread) {
137   // nothing here at the moment
138   assert(t->retired(), "invariant");
139 }
140 
141 void JfrCheckpointManager::lock() {
142   assert(!_lock->owned_by_self(), "invariant");
143   _lock->lock_without_safepoint_check();
144 }
145 
146 void JfrCheckpointManager::unlock() {
147   _lock->unlock();
148 }
149 
150 #ifdef ASSERT
151 
152 bool JfrCheckpointManager::is_locked() const {
153   return _lock->owned_by_self();
154 }
155 
156 static void assert_free_lease(const BufferPtr buffer) {
157   assert(buffer != NULL, "invariant");
158   assert(buffer->acquired_by_self(), "invariant");
159   assert(buffer->lease(), "invariant");
160 }
161 
162 static void assert_release(const BufferPtr buffer) {
163   assert(buffer != NULL, "invariant");
164   assert(buffer->lease(), "invariant");
165   assert(buffer->acquired_by_self(), "invariant");
166 }
167 
168 #endif // ASSERT
169 
170 static BufferPtr lease_free(size_t size, JfrCheckpointMspace* mspace, size_t retry_count, Thread* thread) {
171   static const size_t max_elem_size = mspace->min_elem_size(); // min is max
172   BufferPtr buffer;
173   if (size <= max_elem_size) {
174     BufferPtr buffer = mspace_get_free_lease_with_retry(size, mspace, retry_count, thread);
175     if (buffer != NULL) {
176       DEBUG_ONLY(assert_free_lease(buffer);)
177       return buffer;
178     }
179   }
180   buffer = mspace_allocate_transient_lease_to_free(size, mspace, thread);
181   DEBUG_ONLY(assert_free_lease(buffer);)
182   return buffer;
183 }
184 
185 static const size_t lease_retry = 10;
186 
187 BufferPtr JfrCheckpointManager::lease_buffer(Thread* thread, size_t size /* 0 */) {
188   JfrCheckpointManager& manager = instance();
189   if (manager.use_epoch_transition_mspace(thread)) {
190     return lease_free(size, manager._epoch_transition_mspace, lease_retry, thread);
191   }
192   return lease_free(size, manager._free_list_mspace, lease_retry, thread);
193 }
194 
195 /*
196 * If the buffer was a "lease" from the free list, release back.
197 *
198 * The buffer is effectively invalidated for the thread post-return,
199 * and the caller should take means to ensure that it is not referenced.
200 */
201 static void release(BufferPtr const buffer, Thread* thread) {
202   DEBUG_ONLY(assert_release(buffer);)
203   buffer->clear_lease();
204   buffer->release();
205 }
206 
207 BufferPtr JfrCheckpointManager::flush(BufferPtr old, size_t used, size_t requested, Thread* thread) {
208   assert(old != NULL, "invariant");
209   assert(old->lease(), "invariant");
210   if (0 == requested) {
211     // indicates a lease is being returned
212     release(old, thread);
213     return NULL;
214   }
215   // migration of in-flight information
216   BufferPtr const new_buffer = lease_buffer(thread, used + requested);
217   if (new_buffer != NULL) {
218     migrate_outstanding_writes(old, new_buffer, used, requested);
219   }
220   release(old, thread);
221   return new_buffer; // might be NULL
222 }
223 
224 // offsets into the JfrCheckpointEntry
225 static const juint starttime_offset = sizeof(jlong);
226 static const juint duration_offset = starttime_offset + sizeof(jlong);
227 static const juint flushpoint_offset = duration_offset + sizeof(jlong);
228 static const juint types_offset = flushpoint_offset + sizeof(juint);
229 static const juint payload_offset = types_offset + sizeof(juint);
230 
231 template <typename Return>
232 static Return read_data(const u1* data) {
233   return JfrBigEndian::read<Return>(data);
234 }
235 
236 static jlong total_size(const u1* data) {
237   return read_data<jlong>(data);
238 }
239 
240 static jlong starttime(const u1* data) {
241   return read_data<jlong>(data + starttime_offset);
242 }
243 
244 static jlong duration(const u1* data) {
245   return read_data<jlong>(data + duration_offset);
246 }
247 
248 static bool is_flushpoint(const u1* data) {
249   return read_data<juint>(data + flushpoint_offset) == (juint)1;
250 }
251 
252 static juint number_of_types(const u1* data) {
253   return read_data<juint>(data + types_offset);
254 }
255 
256 static void write_checkpoint_header(JfrChunkWriter& cw, intptr_t offset_prev_cp_event, const u1* data) {
257   cw.reserve(sizeof(u4));
258   cw.write((u8)EVENT_CHECKPOINT);
259   cw.write(starttime(data));
260   cw.write(duration(data));
261   cw.write((jlong)offset_prev_cp_event);
262   cw.write(is_flushpoint(data));
263   cw.write(number_of_types(data));
264 }
265 
266 static void write_checkpoint_content(JfrChunkWriter& cw, const u1* data, size_t size) {
267   assert(data != NULL, "invariant");
268   cw.write_unbuffered(data + payload_offset, size);
269 }
270 
271 static size_t write_checkpoint_event(JfrChunkWriter& cw, const u1* data) {
272   assert(data != NULL, "invariant");
273   const intptr_t previous_checkpoint_event = cw.previous_checkpoint_offset();
274   const intptr_t event_begin = cw.current_offset();
275   const intptr_t offset_to_previous_checkpoint_event = 0 == previous_checkpoint_event ? 0 : previous_checkpoint_event - event_begin;
276   const jlong total_checkpoint_size = total_size(data);
277   write_checkpoint_header(cw, offset_to_previous_checkpoint_event, data);
278   write_checkpoint_content(cw, data, total_checkpoint_size - sizeof(JfrCheckpointEntry));
279   const jlong checkpoint_event_size = cw.current_offset() - event_begin;
280   cw.write_padded_at_offset<u4>(checkpoint_event_size, event_begin);
281   cw.set_previous_checkpoint_offset(event_begin);
282   return (size_t)total_checkpoint_size;
283 }
284 
285 static size_t write_checkpoints(JfrChunkWriter& cw, const u1* data, size_t size) {
286   assert(cw.is_valid(), "invariant");
287   assert(data != NULL, "invariant");
288   assert(size > 0, "invariant");
289   const u1* const limit = data + size;
290   const u1* next_entry = data;
291   size_t processed = 0;
292   while (next_entry < limit) {
293     const size_t checkpoint_size = write_checkpoint_event(cw, next_entry);
294     processed += checkpoint_size;
295     next_entry += checkpoint_size;
296   }
297   assert(next_entry == limit, "invariant");
298   return processed;
299 }
300 
301 template <typename T>
302 class CheckpointWriteOp {
303  private:
304   JfrChunkWriter& _writer;
305   size_t _processed;
306  public:
307   typedef T Type;
308   CheckpointWriteOp(JfrChunkWriter& writer) : _writer(writer), _processed(0) {}
309   bool write(Type* t, const u1* data, size_t size) {
310     _processed += write_checkpoints(_writer, data, size);
311     return true;
312   }
313   size_t processed() const { return _processed; }
314 };
315 
316 typedef CheckpointWriteOp<JfrCheckpointMspace::Type> WriteOperation;
317 typedef MutexedWriteOp<WriteOperation> MutexedWriteOperation;
318 typedef ReleaseOp<JfrCheckpointMspace> CheckpointReleaseOperation;
319 typedef CompositeOperation<MutexedWriteOperation, CheckpointReleaseOperation> CheckpointWriteOperation;
320 
321 static size_t write_mspace_exclusive(JfrCheckpointMspace* mspace, JfrChunkWriter& chunkwriter) {
322   Thread* const thread = Thread::current();
323   WriteOperation wo(chunkwriter);
324   MutexedWriteOperation mwo(wo);
325   CheckpointReleaseOperation cro(mspace, thread, false);
326   CheckpointWriteOperation cpwo(&mwo, &cro);
327   assert(mspace->is_full_empty(), "invariant");
328   process_free_list(cpwo, mspace);
329   return wo.processed();
330 }
331 
332 size_t JfrCheckpointManager::write() {
333   const size_t processed = write_mspace_exclusive(_free_list_mspace, _chunkwriter);
334   synchronize_epoch();
335   return processed;
336 }
337 
338 size_t JfrCheckpointManager::write_epoch_transition_mspace() {
339   return write_mspace_exclusive(_epoch_transition_mspace, _chunkwriter);
340 }
341 
342 typedef DiscardOp<DefaultDiscarder<JfrBuffer> > DiscardOperation;
343 size_t JfrCheckpointManager::clear() {
344   DiscardOperation discarder(mutexed); // mutexed discard mode
345   process_free_list(discarder, _free_list_mspace);
346   process_free_list(discarder, _epoch_transition_mspace);
347   synchronize_epoch();
348   return discarder.processed();
349 }
350 
351 size_t JfrCheckpointManager::write_types() {
352   JfrCheckpointWriter writer(false, true, Thread::current());
353   JfrTypeManager::write_types(writer);
354   return writer.used_size();
355 }
356 
357 size_t JfrCheckpointManager::write_safepoint_types() {
358   // this is also a "flushpoint"
359   JfrCheckpointWriter writer(true, true, Thread::current());
360   JfrTypeManager::write_safepoint_types(writer);
361   return writer.used_size();
362 }
363 
364 void JfrCheckpointManager::write_type_set() {
365   JfrTypeManager::write_type_set();
366 }
367 
368 void JfrCheckpointManager::write_type_set_for_unloaded_classes() {

369   JfrTypeManager::write_type_set_for_unloaded_classes();
370 }
371 
372 void JfrCheckpointManager::create_thread_checkpoint(JavaThread* jt) {
373   JfrTypeManager::create_thread_checkpoint(jt);
374 }
375 
376 void JfrCheckpointManager::write_thread_checkpoint(JavaThread* jt) {
377   JfrTypeManager::write_thread_checkpoint(jt);
378 }
--- EOF ---