1 /*
2 * Copyright (c) 2012, 2013, 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 #ifndef SHARE_VM_SERVICES_MEM_TRACKER_HPP
26 #define SHARE_VM_SERVICES_MEM_TRACKER_HPP
27
28 #include "memory/allocation.hpp"
29 #include "runtime/globals.hpp"
30 #include "runtime/mutex.hpp"
31 #include "runtime/os.hpp"
32 #include "runtime/thread.hpp"
33 #include "services/memPtr.hpp"
34 #include "services/memRecorder.hpp"
35 #include "services/memSnapshot.hpp"
36 #include "services/memTrackWorker.hpp"
37
38 #ifdef SOLARIS
39 #include "thread_solaris.inline.hpp"
40 #endif
41
42 extern bool NMT_track_callsite;
43
44 #ifndef MAX_UNSIGNED_LONG
45 #define MAX_UNSIGNED_LONG (unsigned long)(-1)
46 #endif
47
48 #ifdef ASSERT
49 #define DEBUG_CALLER_PC (NMT_track_callsite ? os::get_caller_pc(2) : 0)
50 #else
51 #define DEBUG_CALLER_PC 0
52 #endif
53
54 // The thread closure walks threads to collect per-thread
55 // memory recorders at NMT sync point
56 class SyncThreadRecorderClosure : public ThreadClosure {
57 private:
58 int _thread_count;
59
60 public:
61 SyncThreadRecorderClosure() {
62 _thread_count =0;
63 }
64
65 void do_thread(Thread* thread);
66 int get_thread_count() const {
67 return _thread_count;
68 }
69 };
70
71 class BaselineOutputer;
72 class MemSnapshot;
73 class MemTrackWorker;
74 class Thread;
75 /*
76 * MemTracker is the 'gate' class to native memory tracking runtime.
77 */
78 class MemTracker : AllStatic {
79 friend class GenerationData;
80 friend class MemTrackWorker;
81 friend class MemSnapshot;
82 friend class SyncThreadRecorderClosure;
83
84 // NMT state
85 enum NMTStates {
86 NMT_uninited, // not yet initialized
87 NMT_bootstrapping_single_thread, // bootstrapping, VM is in single thread mode
88 NMT_bootstrapping_multi_thread, // bootstrapping, VM is about to enter multi-thread mode
89 NMT_started, // NMT fully started
90 NMT_shutdown_pending, // shutdown pending
91 NMT_final_shutdown, // in final phase of shutdown
92 NMT_shutdown // shutdown
93 };
94
95 public:
96 class Tracker : public StackObj {
97 friend class MemTracker;
98 public:
99 enum MemoryOperation {
100 NoOp, // no op
101 Malloc, // malloc
102 Realloc, // realloc
103 Free, // free
104 Reserve, // virtual memory reserve
105 Commit, // virtual memory commit
106 ReserveAndCommit, // virtual memory reserve and commit
107 StackAlloc = ReserveAndCommit, // allocate thread stack
108 Type, // assign virtual memory type
109 Uncommit, // virtual memory uncommit
110 Release, // virtual memory release
111 ArenaSize, // set arena size
112 StackRelease // release thread stack
113 };
114
115
116 protected:
117 Tracker(MemoryOperation op, Thread* thr = NULL);
118
119 public:
120 void discard();
121
122 void record(address addr, size_t size = 0, MEMFLAGS flags = mtNone, address pc = NULL);
123 void record(address old_addr, address new_addr, size_t size,
124 MEMFLAGS flags, address pc = NULL);
125
126 private:
127 bool _need_thread_critical_lock;
128 JavaThread* _java_thread;
129 MemoryOperation _op; // memory operation
130 jint _seq; // reserved sequence number
131 };
132
133
134 public:
135 // native memory tracking level
136 enum NMTLevel {
137 NMT_off, // native memory tracking is off
138 NMT_summary, // don't track callsite
139 NMT_detail // track callsite also
140 };
141
142 enum ShutdownReason {
143 NMT_shutdown_none, // no shutdown requested
144 NMT_shutdown_user, // user requested shutdown
145 NMT_normal, // normal shutdown, process exit
146 NMT_out_of_memory, // shutdown due to out of memory
147 NMT_initialization, // shutdown due to initialization failure
148 NMT_use_malloc_only, // can not combine NMT with UseMallocOnly flag
149 NMT_error_reporting, // shutdown by vmError::report_and_die()
150 NMT_out_of_generation, // running out of generation queue
151 NMT_sequence_overflow // overflow the sequence number
152 };
153
154 public:
155 // initialize NMT tracking level from command line options, called
156 // from VM command line parsing code
157 static void init_tracking_options(const char* option_line);
158
159 // if NMT is enabled to record memory activities
160 static inline bool is_on() {
161 return (_tracking_level >= NMT_summary &&
162 _state >= NMT_bootstrapping_single_thread);
163 }
164
165 static inline enum NMTLevel tracking_level() {
166 return _tracking_level;
167 }
168
169 // user readable reason for shutting down NMT
170 static const char* reason() {
171 switch(_reason) {
172 case NMT_shutdown_none:
173 return "Native memory tracking is not enabled";
174 case NMT_shutdown_user:
175 return "Native memory tracking has been shutdown by user";
176 case NMT_normal:
177 return "Native memory tracking has been shutdown due to process exiting";
178 case NMT_out_of_memory:
179 return "Native memory tracking has been shutdown due to out of native memory";
180 case NMT_initialization:
181 return "Native memory tracking failed to initialize";
182 case NMT_error_reporting:
183 return "Native memory tracking has been shutdown due to error reporting";
184 case NMT_out_of_generation:
185 return "Native memory tracking has been shutdown due to running out of generation buffer";
186 case NMT_sequence_overflow:
187 return "Native memory tracking has been shutdown due to overflow the sequence number";
188 case NMT_use_malloc_only:
189 return "Native memory tracking is not supported when UseMallocOnly is on";
190 default:
191 ShouldNotReachHere();
192 return NULL;
193 }
194 }
195
196 // test if we can walk native stack
197 static bool can_walk_stack() {
198 // native stack is not walkable during bootstrapping on sparc
199 #if defined(SPARC)
200 return (_state == NMT_started);
201 #else
202 return (_state >= NMT_bootstrapping_single_thread && _state <= NMT_started);
203 #endif
204 }
205
206 // if native memory tracking tracks callsite
207 static inline bool track_callsite() { return _tracking_level == NMT_detail; }
208
209 // NMT automatically shuts itself down under extreme situation by default.
210 // When the value is set to false, NMT will try its best to stay alive,
211 // even it has to slow down VM.
212 static inline void set_autoShutdown(bool value) {
213 AutoShutdownNMT = value;
214 if (AutoShutdownNMT && _slowdown_calling_thread) {
215 _slowdown_calling_thread = false;
216 }
217 }
218
219 // shutdown native memory tracking capability. Native memory tracking
220 // can be shutdown by VM when it encounters low memory scenarios.
221 // Memory tracker should gracefully shutdown itself, and preserve the
222 // latest memory statistics for post morten diagnosis.
223 static void shutdown(ShutdownReason reason);
224
225 // if there is shutdown requested
226 static inline bool shutdown_in_progress() {
227 return (_state >= NMT_shutdown_pending);
228 }
229
230 // bootstrap native memory tracking, so it can start to collect raw data
231 // before worker thread can start
232
233 // the first phase of bootstrapping, when VM still in single-threaded mode
234 static void bootstrap_single_thread();
235 // the second phase of bootstrapping, VM is about or already in multi-threaded mode
236 static void bootstrap_multi_thread();
237
238 private:
239 static Tracker _tkr;
240
241 public:
242 // start() has to be called when VM still in single thread mode, but after
243 // command line option parsing is done.
244 static void start();
245
246 // record a 'malloc' call
247 static inline void record_malloc(address addr, size_t size, MEMFLAGS flags,
248 address pc = 0, Thread* thread = NULL) {
249 Tracker tkr(Tracker::Malloc, thread);
250 tkr.record(addr, size, flags, pc);
251 }
252 // record a 'free' call
253 static inline void record_free(address addr, MEMFLAGS flags, Thread* thread = NULL) {
254 Tracker tkr(Tracker::Free, thread);
255 tkr.record(addr, 0, flags, DEBUG_CALLER_PC);
256 }
257
258 static inline void record_arena_size(address addr, size_t size) {
259 Tracker tkr(Tracker::ArenaSize);
260 tkr.record(addr, size);
261 }
262
263 // record a virtual memory 'reserve' call
264 static inline void record_virtual_memory_reserve(address addr, size_t size,
265 MEMFLAGS flags, address pc = 0, Thread* thread = NULL) {
266 if (is_on()) {
267 assert(size > 0, "Sanity check");
268 Tracker tkr(Tracker::Reserve, thread);
269 tkr.record(addr, size, flags, pc);
270 }
271 }
272
273 static inline void record_thread_stack(address addr, size_t size, Thread* thr,
274 address pc = 0) {
275 if (is_on()) {
276 Tracker tkr(Tracker::StackAlloc, thr);
277 tkr.record(addr, size, mtThreadStack, pc);
278 }
279 }
280
281 static inline void release_thread_stack(address addr, size_t size, Thread* thr) {
282 if (is_on()) {
283 Tracker tkr(Tracker::StackRelease, thr);
284 tkr.record(addr, size, mtThreadStack, DEBUG_CALLER_PC);
285 }
286 }
287
288 // record a virtual memory 'commit' call
289 static inline void record_virtual_memory_commit(address addr, size_t size,
290 address pc, Thread* thread = NULL) {
291 if (is_on()) {
292 Tracker tkr(Tracker::Commit, thread);
293 tkr.record(addr, size, mtNone, pc);
294 }
295 }
296
297 static inline void record_virtual_memory_reserve_and_commit(address addr, size_t size,
298 MEMFLAGS flags, address pc, Thread* thread = NULL) {
299 if (is_on()) {
300 Tracker tkr(Tracker::ReserveAndCommit, thread);
301 tkr.record(addr, size, flags, pc);
302 }
303 }
304
305
306 // record memory type on virtual memory base address
307 static inline void record_virtual_memory_type(address base, MEMFLAGS flags,
308 Thread* thread = NULL) {
309 if (is_on()) {
310 Tracker tkr(Tracker::Type);
311 tkr.record(base, 0, flags);
312 }
313 }
314
315 // Get memory trackers for memory operations that can result race conditions.
316 // The memory tracker has to be obtained before realloc, virtual memory uncommit
317 // and virtual memory release, and call tracker.record() method if operation
318 // succeeded, or tracker.discard() to abort the tracking.
319 static inline Tracker get_realloc_tracker() {
320 return Tracker(Tracker::Realloc);
321 }
322
323 static inline Tracker get_virtual_memory_uncommit_tracker() {
324 return Tracker(Tracker::Uncommit);
325 }
326
327 static inline Tracker get_virtual_memory_release_tracker() {
328 return Tracker(Tracker::Release);
329 }
330
331
332 // create memory baseline of current memory snapshot
333 static bool baseline();
334 // is there a memory baseline
335 static bool has_baseline() {
336 return _baseline.baselined();
337 }
338
339 // print memory usage from current snapshot
340 static bool print_memory_usage(BaselineOutputer& out, size_t unit,
341 bool summary_only = true);
342 // compare memory usage between current snapshot and baseline
343 static bool compare_memory_usage(BaselineOutputer& out, size_t unit,
344 bool summary_only = true);
345
346 // the version for whitebox testing support, it ensures that all memory
347 // activities before this method call, are reflected in the snapshot
348 // database.
349 static bool wbtest_wait_for_data_merge();
350
351 // sync is called within global safepoint to synchronize nmt data
352 static void sync();
353
354 // called when a thread is about to exit
355 static void thread_exiting(JavaThread* thread);
356
357 // retrieve global snapshot
358 static MemSnapshot* get_snapshot() {
359 if (shutdown_in_progress()) {
360 return NULL;
361 }
362 return _snapshot;
363 }
364
365 // print tracker stats
366 NOT_PRODUCT(static void print_tracker_stats(outputStream* st);)
367 NOT_PRODUCT(static void walk_stack(int toSkip, char* buf, int len);)
368
369 private:
370 // start native memory tracking worker thread
371 static bool start_worker(MemSnapshot* snapshot);
372
373 // called by worker thread to complete shutdown process
374 static void final_shutdown();
375
376 protected:
377 // retrieve per-thread recorder of the specified thread.
378 // if the recorder is full, it will be enqueued to overflow
379 // queue, a new recorder is acquired from recorder pool or a
380 // new instance is created.
381 // when thread == NULL, it means global recorder
382 static MemRecorder* get_thread_recorder(JavaThread* thread);
383
384 // per-thread recorder pool
385 static void release_thread_recorder(MemRecorder* rec);
386 static void delete_all_pooled_recorders();
387
388 // pending recorder queue. Recorders are queued to pending queue
389 // when they are overflowed or collected at nmt sync point.
390 static void enqueue_pending_recorder(MemRecorder* rec);
391 static MemRecorder* get_pending_recorders();
392 static void delete_all_pending_recorders();
393
394 // write a memory tracking record in recorder
395 static void write_tracking_record(address addr, MEMFLAGS type,
396 size_t size, jint seq, address pc, JavaThread* thread);
397
398 static bool is_single_threaded_bootstrap() {
399 return _state == NMT_bootstrapping_single_thread;
400 }
401
402 static void check_NMT_load(Thread* thr) {
403 assert(thr != NULL, "Sanity check");
404 if (_slowdown_calling_thread && thr != _worker_thread) {
405 os::yield_all();
406 }
407 }
408
409 static void inc_pending_op_count() {
410 Atomic::inc(&_pending_op_count);
411 }
412
413 static void dec_pending_op_count() {
414 Atomic::dec(&_pending_op_count);
415 assert(_pending_op_count >= 0, "Sanity check");
416 }
417
418
419 private:
420 // retrieve a pooled memory record or create new one if there is not
421 // one available
422 static MemRecorder* get_new_or_pooled_instance();
423 static void create_memory_record(address addr, MEMFLAGS type,
424 size_t size, address pc, Thread* thread);
425 static void create_record_in_recorder(address addr, MEMFLAGS type,
426 size_t size, address pc, JavaThread* thread);
427
428 static void set_current_processing_generation(unsigned long generation) {
429 _worker_thread_idle = false;
430 _processing_generation = generation;
431 }
432
433 static void report_worker_idle() {
434 _worker_thread_idle = true;
435 }
436
437 private:
438 // global memory snapshot
439 static MemSnapshot* _snapshot;
440
441 // a memory baseline of snapshot
442 static MemBaseline _baseline;
443
444 // query lock
445 static Mutex* _query_lock;
446
447 // a thread can start to allocate memory before it is attached
448 // to VM 'Thread', those memory activities are recorded here.
449 // ThreadCritical is required to guard this global recorder.
450 static MemRecorder* volatile _global_recorder;
451
452 // main thread id
453 debug_only(static intx _main_thread_tid;)
454
455 // pending recorders to be merged
456 static MemRecorder* volatile _merge_pending_queue;
457
458 NOT_PRODUCT(static volatile jint _pending_recorder_count;)
459
460 // pooled memory recorders
461 static MemRecorder* volatile _pooled_recorders;
462
463 // memory recorder pool management, uses following
464 // counter to determine if a released memory recorder
465 // should be pooled
466
467 // latest thread count
468 static int _thread_count;
469 // pooled recorder count
470 static volatile jint _pooled_recorder_count;
471
472
473 // worker thread to merge pending recorders into snapshot
474 static MemTrackWorker* _worker_thread;
475
476 // how many safepoints we skipped without entering sync point
477 static int _sync_point_skip_count;
478
479 // if the tracker is properly intialized
480 static bool _is_tracker_ready;
481 // tracking level (off, summary and detail)
482 static enum NMTLevel _tracking_level;
483
484 // current nmt state
485 static volatile enum NMTStates _state;
486 // the reason for shutting down nmt
487 static enum ShutdownReason _reason;
488 // the generation that NMT is processing
489 static volatile unsigned long _processing_generation;
490 // although NMT is still procesing current generation, but
491 // there is not more recorder to process, set idle state
492 static volatile bool _worker_thread_idle;
493
494 // if NMT should slow down calling thread to allow
495 // worker thread to catch up
496 static volatile bool _slowdown_calling_thread;
497
498 // pending memory op count.
499 // Certain memory ops need to pre-reserve sequence number
500 // before memory operation can happen to avoid race condition.
501 // See MemTracker::Tracker for detail
502 static volatile jint _pending_op_count;
503 };
504
505 #endif // SHARE_VM_SERVICES_MEM_TRACKER_HPP