trace.cc revision 5ce4b178d2483df679e7f718e379305e5d42a300 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "trace.h"
18
19#include <sys/uio.h>
20
21#include "base/stl_util.h"
22#include "base/unix_file/fd_file.h"
23#include "class_linker.h"
24#include "common_throws.h"
25#include "debugger.h"
26#include "dex_file-inl.h"
27#include "instrumentation.h"
28#include "mirror/art_method-inl.h"
29#include "mirror/class-inl.h"
30#include "mirror/dex_cache.h"
31#include "mirror/object_array-inl.h"
32#include "mirror/object-inl.h"
33#include "object_utils.h"
34#include "os.h"
35#include "scoped_thread_state_change.h"
36#include "ScopedLocalRef.h"
37#include "thread.h"
38#include "thread_list.h"
39#if !defined(ART_USE_PORTABLE_COMPILER)
40#include "entrypoints/quick/quick_entrypoints.h"
41#endif
42
43namespace art {
44
45// File format:
46//     header
47//     record 0
48//     record 1
49//     ...
50//
51// Header format:
52//     u4  magic ('SLOW')
53//     u2  version
54//     u2  offset to data
55//     u8  start date/time in usec
56//     u2  record size in bytes (version >= 2 only)
57//     ... padding to 32 bytes
58//
59// Record format v1:
60//     u1  thread ID
61//     u4  method ID | method action
62//     u4  time delta since start, in usec
63//
64// Record format v2:
65//     u2  thread ID
66//     u4  method ID | method action
67//     u4  time delta since start, in usec
68//
69// Record format v3:
70//     u2  thread ID
71//     u4  method ID | method action
72//     u4  time delta since start, in usec
73//     u4  wall time since start, in usec (when clock == "dual" only)
74//
75// 32 bits of microseconds is 70 minutes.
76//
77// All values are stored in little-endian order.
78
79enum TraceAction {
80    kTraceMethodEnter = 0x00,       // method entry
81    kTraceMethodExit = 0x01,        // method exit
82    kTraceUnroll = 0x02,            // method exited by exception unrolling
83    // 0x03 currently unused
84    kTraceMethodActionMask = 0x03,  // two bits
85};
86
87class BuildStackTraceVisitor : public StackVisitor {
88 public:
89  explicit BuildStackTraceVisitor(Thread* thread) : StackVisitor(thread, NULL),
90      method_trace_(Trace::AllocStackTrace()) {}
91
92  bool VisitFrame() {
93    mirror::ArtMethod* m = GetMethod();
94    // Ignore runtime frames (in particular callee save).
95    if (!m->IsRuntimeMethod()) {
96      method_trace_->push_back(m);
97    }
98    return true;
99  }
100
101  // Returns a stack trace where the topmost frame corresponds with the first element of the vector.
102  std::vector<mirror::ArtMethod*>* GetStackTrace() const {
103    return method_trace_;
104  }
105
106 private:
107  std::vector<mirror::ArtMethod*>* const method_trace_;
108};
109
110static const char     kTraceTokenChar             = '*';
111static const uint16_t kTraceHeaderLength          = 32;
112static const uint32_t kTraceMagicValue            = 0x574f4c53;
113static const uint16_t kTraceVersionSingleClock    = 2;
114static const uint16_t kTraceVersionDualClock      = 3;
115static const uint16_t kTraceRecordSizeSingleClock = 10;  // using v2
116static const uint16_t kTraceRecordSizeDualClock   = 14;  // using v3 with two timestamps
117
118#if defined(HAVE_POSIX_CLOCKS)
119ProfilerClockSource Trace::default_clock_source_ = kProfilerClockSourceDual;
120#else
121ProfilerClockSource Trace::default_clock_source_ = kProfilerClockSourceWall;
122#endif
123
124Trace* volatile Trace::the_trace_ = NULL;
125// TODO: Add way to enable sampling and set interval through gui.
126bool Trace::sampling_enabled_ = true;
127uint32_t Trace::sampling_interval_us_ = 10000;
128pthread_t Trace::sampling_pthread_ = 0U;
129UniquePtr<std::vector<mirror::ArtMethod*> > Trace::temp_stack_trace_;
130
131static mirror::ArtMethod* DecodeTraceMethodId(uint32_t tmid) {
132  return reinterpret_cast<mirror::ArtMethod*>(tmid & ~kTraceMethodActionMask);
133}
134
135static TraceAction DecodeTraceAction(uint32_t tmid) {
136  return static_cast<TraceAction>(tmid & kTraceMethodActionMask);
137}
138
139static uint32_t EncodeTraceMethodAndAction(const mirror::ArtMethod* method,
140                                           TraceAction action) {
141  uint32_t tmid = reinterpret_cast<uint32_t>(method) | action;
142  DCHECK_EQ(method, DecodeTraceMethodId(tmid));
143  return tmid;
144}
145
146std::vector<mirror::ArtMethod*>* Trace::AllocStackTrace() {
147  if (temp_stack_trace_.get() != NULL) {
148    return temp_stack_trace_.release();
149  } else {
150    return new std::vector<mirror::ArtMethod*>();
151  }
152}
153
154void Trace::FreeStackTrace(std::vector<mirror::ArtMethod*>* stack_trace) {
155  stack_trace->clear();
156  temp_stack_trace_.reset(stack_trace);
157}
158
159void Trace::SetDefaultClockSource(ProfilerClockSource clock_source) {
160#if defined(HAVE_POSIX_CLOCKS)
161  default_clock_source_ = clock_source;
162#else
163  if (clock_source != kProfilerClockSourceWall) {
164    LOG(WARNING) << "Ignoring tracing request to use CPU time.";
165  }
166#endif
167}
168
169static uint16_t GetTraceVersion(ProfilerClockSource clock_source) {
170  return (clock_source == kProfilerClockSourceDual) ? kTraceVersionDualClock
171                                                    : kTraceVersionSingleClock;
172}
173
174static uint16_t GetRecordSize(ProfilerClockSource clock_source) {
175  return (clock_source == kProfilerClockSourceDual) ? kTraceRecordSizeDualClock
176                                                    : kTraceRecordSizeSingleClock;
177}
178
179bool Trace::UseThreadCpuClock() {
180  return (clock_source_ == kProfilerClockSourceThreadCpu) ||
181      (clock_source_ == kProfilerClockSourceDual);
182}
183
184bool Trace::UseWallClock() {
185  return (clock_source_ == kProfilerClockSourceWall) ||
186      (clock_source_ == kProfilerClockSourceDual);
187}
188
189static void MeasureClockOverhead(Trace* trace) {
190  if (trace->UseThreadCpuClock()) {
191    Thread::Current()->GetCpuMicroTime();
192  }
193  if (trace->UseWallClock()) {
194    MicroTime();
195  }
196}
197
198// Compute an average time taken to measure clocks.
199static uint32_t GetClockOverheadNanoSeconds(Trace* trace) {
200  Thread* self = Thread::Current();
201  uint64_t start = self->GetCpuMicroTime();
202
203  for (int i = 4000; i > 0; i--) {
204    MeasureClockOverhead(trace);
205    MeasureClockOverhead(trace);
206    MeasureClockOverhead(trace);
207    MeasureClockOverhead(trace);
208    MeasureClockOverhead(trace);
209    MeasureClockOverhead(trace);
210    MeasureClockOverhead(trace);
211    MeasureClockOverhead(trace);
212  }
213
214  uint64_t elapsed_us = self->GetCpuMicroTime() - start;
215  return static_cast<uint32_t>(elapsed_us / 32);
216}
217
218// TODO: put this somewhere with the big-endian equivalent used by JDWP.
219static void Append2LE(uint8_t* buf, uint16_t val) {
220  *buf++ = static_cast<uint8_t>(val);
221  *buf++ = static_cast<uint8_t>(val >> 8);
222}
223
224// TODO: put this somewhere with the big-endian equivalent used by JDWP.
225static void Append4LE(uint8_t* buf, uint32_t val) {
226  *buf++ = static_cast<uint8_t>(val);
227  *buf++ = static_cast<uint8_t>(val >> 8);
228  *buf++ = static_cast<uint8_t>(val >> 16);
229  *buf++ = static_cast<uint8_t>(val >> 24);
230}
231
232// TODO: put this somewhere with the big-endian equivalent used by JDWP.
233static void Append8LE(uint8_t* buf, uint64_t val) {
234  *buf++ = static_cast<uint8_t>(val);
235  *buf++ = static_cast<uint8_t>(val >> 8);
236  *buf++ = static_cast<uint8_t>(val >> 16);
237  *buf++ = static_cast<uint8_t>(val >> 24);
238  *buf++ = static_cast<uint8_t>(val >> 32);
239  *buf++ = static_cast<uint8_t>(val >> 40);
240  *buf++ = static_cast<uint8_t>(val >> 48);
241  *buf++ = static_cast<uint8_t>(val >> 56);
242}
243
244static void GetSample(Thread* thread, void* arg) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
245  BuildStackTraceVisitor build_trace_visitor(thread);
246  build_trace_visitor.WalkStack();
247  std::vector<mirror::ArtMethod*>* stack_trace = build_trace_visitor.GetStackTrace();
248  Trace* the_trace = reinterpret_cast<Trace*>(arg);
249  the_trace->CompareAndUpdateStackTrace(thread, stack_trace);
250}
251
252static void ClearThreadStackTraceAndClockBase(Thread* thread, void* arg) {
253  thread->SetTraceClockBase(0);
254  std::vector<mirror::ArtMethod*>* stack_trace = thread->GetStackTraceSample();
255  thread->SetStackTraceSample(NULL);
256  delete stack_trace;
257}
258
259void Trace::CompareAndUpdateStackTrace(Thread* thread,
260                                       std::vector<mirror::ArtMethod*>* stack_trace) {
261  CHECK_EQ(pthread_self(), sampling_pthread_);
262  std::vector<mirror::ArtMethod*>* old_stack_trace = thread->GetStackTraceSample();
263  // Update the thread's stack trace sample.
264  thread->SetStackTraceSample(stack_trace);
265  if (old_stack_trace == NULL) {
266    // If there's no previous stack trace sample for this thread, log an entry event for all
267    // methods in the trace.
268    for (std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin();
269         rit != stack_trace->rend(); ++rit) {
270      LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered);
271    }
272  } else {
273    // If there's a previous stack trace for this thread, diff the traces and emit entry and exit
274    // events accordingly.
275    std::vector<mirror::ArtMethod*>::reverse_iterator old_rit = old_stack_trace->rbegin();
276    std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin();
277    // Iterate bottom-up over both traces until there's a difference between them.
278    while (old_rit != old_stack_trace->rend() && rit != stack_trace->rend() && *old_rit == *rit) {
279      old_rit++;
280      rit++;
281    }
282    // Iterate top-down over the old trace until the point where they differ, emitting exit events.
283    for (std::vector<mirror::ArtMethod*>::iterator old_it = old_stack_trace->begin();
284         old_it != old_rit.base(); ++old_it) {
285      LogMethodTraceEvent(thread, *old_it, instrumentation::Instrumentation::kMethodExited);
286    }
287    // Iterate bottom-up over the new trace from the point where they differ, emitting entry events.
288    for (; rit != stack_trace->rend(); ++rit) {
289      LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered);
290    }
291    FreeStackTrace(old_stack_trace);
292  }
293}
294
295void* Trace::RunSamplingThread(void* arg) {
296  Runtime* runtime = Runtime::Current();
297  CHECK(runtime->AttachCurrentThread("Sampling Profiler", true, runtime->GetSystemThreadGroup(),
298                                     !runtime->IsCompiler()));
299
300  while (true) {
301    usleep(sampling_interval_us_);
302    ATRACE_BEGIN("Profile sampling");
303    Thread* self = Thread::Current();
304    Trace* the_trace;
305    {
306      MutexLock mu(self, *Locks::trace_lock_);
307      the_trace = the_trace_;
308      if (the_trace == NULL) {
309        break;
310      }
311    }
312
313    runtime->GetThreadList()->SuspendAll();
314    {
315      MutexLock mu(self, *Locks::thread_list_lock_);
316      runtime->GetThreadList()->ForEach(GetSample, the_trace);
317    }
318    runtime->GetThreadList()->ResumeAll();
319    ATRACE_END();
320  }
321
322  runtime->DetachCurrentThread();
323  return NULL;
324}
325
326void Trace::Start(const char* trace_filename, int trace_fd, int buffer_size, int flags,
327                  bool direct_to_ddms) {
328  Thread* self = Thread::Current();
329  {
330    MutexLock mu(self, *Locks::trace_lock_);
331    if (the_trace_ != NULL) {
332      LOG(ERROR) << "Trace already in progress, ignoring this request";
333      return;
334    }
335  }
336  Runtime* runtime = Runtime::Current();
337  runtime->GetThreadList()->SuspendAll();
338
339  // Open trace file if not going directly to ddms.
340  UniquePtr<File> trace_file;
341  if (!direct_to_ddms) {
342    if (trace_fd < 0) {
343      trace_file.reset(OS::CreateEmptyFile(trace_filename));
344    } else {
345      trace_file.reset(new File(trace_fd, "tracefile"));
346      trace_file->DisableAutoClose();
347    }
348    if (trace_file.get() == NULL) {
349      PLOG(ERROR) << "Unable to open trace file '" << trace_filename << "'";
350      runtime->GetThreadList()->ResumeAll();
351      ScopedObjectAccess soa(self);
352      ThrowRuntimeException("Unable to open trace file '%s'", trace_filename);
353      return;
354    }
355  }
356
357  // Create Trace object.
358  {
359    MutexLock mu(self, *Locks::trace_lock_);
360    if (the_trace_ != NULL) {
361      LOG(ERROR) << "Trace already in progress, ignoring this request";
362    } else {
363      the_trace_ = new Trace(trace_file.release(), buffer_size, flags);
364
365      // Enable count of allocs if specified in the flags.
366      if ((flags && kTraceCountAllocs) != 0) {
367        runtime->SetStatsEnabled(true);
368      }
369
370      if (sampling_enabled_) {
371        CHECK_PTHREAD_CALL(pthread_create, (&sampling_pthread_, NULL, &RunSamplingThread, NULL),
372                           "Sampling profiler thread");
373      } else {
374        runtime->GetInstrumentation()->AddListener(the_trace_,
375                                                   instrumentation::Instrumentation::kMethodEntered |
376                                                   instrumentation::Instrumentation::kMethodExited |
377                                                   instrumentation::Instrumentation::kMethodUnwind);
378      }
379    }
380  }
381  runtime->GetThreadList()->ResumeAll();
382}
383
384void Trace::Stop() {
385  Runtime* runtime = Runtime::Current();
386  runtime->GetThreadList()->SuspendAll();
387  Trace* the_trace = NULL;
388  pthread_t sampling_pthread = 0U;
389  {
390    MutexLock mu(Thread::Current(), *Locks::trace_lock_);
391    if (the_trace_ == NULL) {
392      LOG(ERROR) << "Trace stop requested, but no trace currently running";
393    } else {
394      the_trace = the_trace_;
395      the_trace_ = NULL;
396      sampling_pthread = sampling_pthread_;
397      sampling_pthread_ = 0U;
398    }
399  }
400  if (the_trace != NULL) {
401    the_trace->FinishTracing();
402
403    if (sampling_enabled_) {
404      MutexLock mu(Thread::Current(), *Locks::thread_list_lock_);
405      runtime->GetThreadList()->ForEach(ClearThreadStackTraceAndClockBase, NULL);
406    } else {
407      runtime->GetInstrumentation()->RemoveListener(the_trace,
408                                                    instrumentation::Instrumentation::kMethodEntered |
409                                                    instrumentation::Instrumentation::kMethodExited |
410                                                    instrumentation::Instrumentation::kMethodUnwind);
411    }
412    delete the_trace;
413  }
414  runtime->GetThreadList()->ResumeAll();
415
416  if (sampling_enabled_ && sampling_pthread != 0U) {
417    CHECK_PTHREAD_CALL(pthread_join, (sampling_pthread, NULL), "sampling thread shutdown");
418  }
419}
420
421void Trace::Shutdown() {
422  if (IsMethodTracingActive()) {
423    Stop();
424  }
425}
426
427bool Trace::IsMethodTracingActive() {
428  MutexLock mu(Thread::Current(), *Locks::trace_lock_);
429  return the_trace_ != NULL;
430}
431
432Trace::Trace(File* trace_file, int buffer_size, int flags)
433    : trace_file_(trace_file), buf_(new uint8_t[buffer_size]()), flags_(flags),
434      clock_source_(default_clock_source_), buffer_size_(buffer_size), start_time_(MicroTime()),
435      cur_offset_(0),  overflow_(false) {
436  // Set up the beginning of the trace.
437  uint16_t trace_version = GetTraceVersion(clock_source_);
438  memset(buf_.get(), 0, kTraceHeaderLength);
439  Append4LE(buf_.get(), kTraceMagicValue);
440  Append2LE(buf_.get() + 4, trace_version);
441  Append2LE(buf_.get() + 6, kTraceHeaderLength);
442  Append8LE(buf_.get() + 8, start_time_);
443  if (trace_version >= kTraceVersionDualClock) {
444    uint16_t record_size = GetRecordSize(clock_source_);
445    Append2LE(buf_.get() + 16, record_size);
446  }
447
448  // Update current offset.
449  cur_offset_ = kTraceHeaderLength;
450}
451
452Trace::~Trace() {
453  CHECK_EQ(sampling_pthread_, static_cast<pthread_t>(0U));
454}
455
456static void DumpBuf(uint8_t* buf, size_t buf_size, ProfilerClockSource clock_source)
457    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
458  uint8_t* ptr = buf + kTraceHeaderLength;
459  uint8_t* end = buf + buf_size;
460
461  while (ptr < end) {
462    uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24);
463    mirror::ArtMethod* method = DecodeTraceMethodId(tmid);
464    TraceAction action = DecodeTraceAction(tmid);
465    LOG(INFO) << PrettyMethod(method) << " " << static_cast<int>(action);
466    ptr += GetRecordSize(clock_source);
467  }
468}
469
470void Trace::FinishTracing() {
471  // Compute elapsed time.
472  uint64_t elapsed = MicroTime() - start_time_;
473
474  size_t final_offset = cur_offset_;
475  uint32_t clock_overhead_ns = GetClockOverheadNanoSeconds(this);
476
477  if ((flags_ & kTraceCountAllocs) != 0) {
478    Runtime::Current()->SetStatsEnabled(false);
479  }
480
481  std::set<mirror::ArtMethod*> visited_methods;
482  GetVisitedMethods(final_offset, &visited_methods);
483
484  std::ostringstream os;
485
486  os << StringPrintf("%cversion\n", kTraceTokenChar);
487  os << StringPrintf("%d\n", GetTraceVersion(clock_source_));
488  os << StringPrintf("data-file-overflow=%s\n", overflow_ ? "true" : "false");
489  if (UseThreadCpuClock()) {
490    if (UseWallClock()) {
491      os << StringPrintf("clock=dual\n");
492    } else {
493      os << StringPrintf("clock=thread-cpu\n");
494    }
495  } else {
496    os << StringPrintf("clock=wall\n");
497  }
498  os << StringPrintf("elapsed-time-usec=%llu\n", elapsed);
499  size_t num_records = (final_offset - kTraceHeaderLength) / GetRecordSize(clock_source_);
500  os << StringPrintf("num-method-calls=%zd\n", num_records);
501  os << StringPrintf("clock-call-overhead-nsec=%d\n", clock_overhead_ns);
502  os << StringPrintf("vm=art\n");
503  if ((flags_ & kTraceCountAllocs) != 0) {
504    os << StringPrintf("alloc-count=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_OBJECTS));
505    os << StringPrintf("alloc-size=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_BYTES));
506    os << StringPrintf("gc-count=%d\n", Runtime::Current()->GetStat(KIND_GC_INVOCATIONS));
507  }
508  os << StringPrintf("%cthreads\n", kTraceTokenChar);
509  DumpThreadList(os);
510  os << StringPrintf("%cmethods\n", kTraceTokenChar);
511  DumpMethodList(os, visited_methods);
512  os << StringPrintf("%cend\n", kTraceTokenChar);
513
514  std::string header(os.str());
515  if (trace_file_.get() == NULL) {
516    iovec iov[2];
517    iov[0].iov_base = reinterpret_cast<void*>(const_cast<char*>(header.c_str()));
518    iov[0].iov_len = header.length();
519    iov[1].iov_base = buf_.get();
520    iov[1].iov_len = final_offset;
521    Dbg::DdmSendChunkV(CHUNK_TYPE("MPSE"), iov, 2);
522    const bool kDumpTraceInfo = false;
523    if (kDumpTraceInfo) {
524      LOG(INFO) << "Trace sent:\n" << header;
525      DumpBuf(buf_.get(), final_offset, clock_source_);
526    }
527  } else {
528    if (!trace_file_->WriteFully(header.c_str(), header.length()) ||
529        !trace_file_->WriteFully(buf_.get(), final_offset)) {
530      std::string detail(StringPrintf("Trace data write failed: %s", strerror(errno)));
531      PLOG(ERROR) << detail;
532      ThrowRuntimeException("%s", detail.c_str());
533    }
534  }
535}
536
537void Trace::DexPcMoved(Thread* thread, mirror::Object* this_object,
538                       const mirror::ArtMethod* method, uint32_t new_dex_pc) {
539  // We're not recorded to listen to this kind of event, so complain.
540  LOG(ERROR) << "Unexpected dex PC event in tracing " << PrettyMethod(method) << " " << new_dex_pc;
541};
542
543void Trace::MethodEntered(Thread* thread, mirror::Object* this_object,
544                          const mirror::ArtMethod* method, uint32_t dex_pc) {
545  LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodEntered);
546}
547
548void Trace::MethodExited(Thread* thread, mirror::Object* this_object,
549                         const mirror::ArtMethod* method, uint32_t dex_pc,
550                         const JValue& return_value) {
551  UNUSED(return_value);
552  LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodExited);
553}
554
555void Trace::MethodUnwind(Thread* thread, const mirror::ArtMethod* method, uint32_t dex_pc) {
556  LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodUnwind);
557}
558
559void Trace::ExceptionCaught(Thread* thread, const ThrowLocation& throw_location,
560                            mirror::ArtMethod* catch_method, uint32_t catch_dex_pc,
561                            mirror::Throwable* exception_object)
562    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
563  LOG(ERROR) << "Unexpected exception caught event in tracing";
564}
565
566void Trace::LogMethodTraceEvent(Thread* thread, const mirror::ArtMethod* method,
567                                instrumentation::Instrumentation::InstrumentationEvent event) {
568  // Advance cur_offset_ atomically.
569  int32_t new_offset;
570  int32_t old_offset;
571  do {
572    old_offset = cur_offset_;
573    new_offset = old_offset + GetRecordSize(clock_source_);
574    if (new_offset > buffer_size_) {
575      overflow_ = true;
576      return;
577    }
578  } while (android_atomic_release_cas(old_offset, new_offset, &cur_offset_) != 0);
579
580  TraceAction action = kTraceMethodEnter;
581  switch (event) {
582    case instrumentation::Instrumentation::kMethodEntered:
583      action = kTraceMethodEnter;
584      break;
585    case instrumentation::Instrumentation::kMethodExited:
586      action = kTraceMethodExit;
587      break;
588    case instrumentation::Instrumentation::kMethodUnwind:
589      action = kTraceUnroll;
590      break;
591    default:
592      UNIMPLEMENTED(FATAL) << "Unexpected event: " << event;
593  }
594
595  uint32_t method_value = EncodeTraceMethodAndAction(method, action);
596
597  // Write data
598  uint8_t* ptr = buf_.get() + old_offset;
599  Append2LE(ptr, thread->GetTid());
600  Append4LE(ptr + 2, method_value);
601  ptr += 6;
602
603  if (UseThreadCpuClock()) {
604    uint64_t clock_base = thread->GetTraceClockBase();
605    uint32_t thread_clock_diff = 0;
606    if (UNLIKELY(clock_base == 0)) {
607      // First event, record the base time in the map.
608      uint64_t time = thread->GetCpuMicroTime();
609      thread->SetTraceClockBase(time);
610    } else {
611      thread_clock_diff = thread->GetCpuMicroTime() - clock_base;
612    }
613    Append4LE(ptr, thread_clock_diff);
614    ptr += 4;
615  }
616  if (UseWallClock()) {
617    uint32_t wall_clock_diff = MicroTime() - start_time_;
618    Append4LE(ptr, wall_clock_diff);
619  }
620}
621
622void Trace::GetVisitedMethods(size_t buf_size,
623                              std::set<mirror::ArtMethod*>* visited_methods) {
624  uint8_t* ptr = buf_.get() + kTraceHeaderLength;
625  uint8_t* end = buf_.get() + buf_size;
626
627  while (ptr < end) {
628    uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24);
629    mirror::ArtMethod* method = DecodeTraceMethodId(tmid);
630    visited_methods->insert(method);
631    ptr += GetRecordSize(clock_source_);
632  }
633}
634
635void Trace::DumpMethodList(std::ostream& os,
636                           const std::set<mirror::ArtMethod*>& visited_methods) {
637  typedef std::set<mirror::ArtMethod*>::const_iterator It;  // TODO: C++0x auto
638  MethodHelper mh;
639  for (It it = visited_methods.begin(); it != visited_methods.end(); ++it) {
640    mirror::ArtMethod* method = *it;
641    mh.ChangeMethod(method);
642    os << StringPrintf("%p\t%s\t%s\t%s\t%s\n", method,
643        PrettyDescriptor(mh.GetDeclaringClassDescriptor()).c_str(), mh.GetName(),
644        mh.GetSignature().c_str(), mh.GetDeclaringClassSourceFile());
645  }
646}
647
648static void DumpThread(Thread* t, void* arg) {
649  std::ostream& os = *reinterpret_cast<std::ostream*>(arg);
650  std::string name;
651  t->GetThreadName(name);
652  os << t->GetTid() << "\t" << name << "\n";
653}
654
655void Trace::DumpThreadList(std::ostream& os) {
656  Thread* self = Thread::Current();
657  Locks::thread_list_lock_->AssertNotHeld(self);
658  MutexLock mu(self, *Locks::thread_list_lock_);
659  Runtime::Current()->GetThreadList()->ForEach(DumpThread, &os);
660}
661
662}  // namespace art
663