trace.cc revision c96657c4243e04888d5948fa023d78cc9213800b
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() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 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 118ProfilerClockSource Trace::default_clock_source_ = kDefaultProfilerClockSource; 119 120Trace* volatile Trace::the_trace_ = NULL; 121pthread_t Trace::sampling_pthread_ = 0U; 122std::unique_ptr<std::vector<mirror::ArtMethod*>> Trace::temp_stack_trace_; 123 124static mirror::ArtMethod* DecodeTraceMethodId(uint32_t tmid) { 125 return reinterpret_cast<mirror::ArtMethod*>(tmid & ~kTraceMethodActionMask); 126} 127 128static TraceAction DecodeTraceAction(uint32_t tmid) { 129 return static_cast<TraceAction>(tmid & kTraceMethodActionMask); 130} 131 132static uint32_t EncodeTraceMethodAndAction(mirror::ArtMethod* method, 133 TraceAction action) { 134 uint32_t tmid = PointerToLowMemUInt32(method) | action; 135 DCHECK_EQ(method, DecodeTraceMethodId(tmid)); 136 return tmid; 137} 138 139std::vector<mirror::ArtMethod*>* Trace::AllocStackTrace() { 140 if (temp_stack_trace_.get() != NULL) { 141 return temp_stack_trace_.release(); 142 } else { 143 return new std::vector<mirror::ArtMethod*>(); 144 } 145} 146 147void Trace::FreeStackTrace(std::vector<mirror::ArtMethod*>* stack_trace) { 148 stack_trace->clear(); 149 temp_stack_trace_.reset(stack_trace); 150} 151 152void Trace::SetDefaultClockSource(ProfilerClockSource clock_source) { 153#if defined(HAVE_POSIX_CLOCKS) 154 default_clock_source_ = clock_source; 155#else 156 if (clock_source != kProfilerClockSourceWall) { 157 LOG(WARNING) << "Ignoring tracing request to use CPU time."; 158 } 159#endif 160} 161 162static uint16_t GetTraceVersion(ProfilerClockSource clock_source) { 163 return (clock_source == kProfilerClockSourceDual) ? kTraceVersionDualClock 164 : kTraceVersionSingleClock; 165} 166 167static uint16_t GetRecordSize(ProfilerClockSource clock_source) { 168 return (clock_source == kProfilerClockSourceDual) ? kTraceRecordSizeDualClock 169 : kTraceRecordSizeSingleClock; 170} 171 172bool Trace::UseThreadCpuClock() { 173 return (clock_source_ == kProfilerClockSourceThreadCpu) || 174 (clock_source_ == kProfilerClockSourceDual); 175} 176 177bool Trace::UseWallClock() { 178 return (clock_source_ == kProfilerClockSourceWall) || 179 (clock_source_ == kProfilerClockSourceDual); 180} 181 182void Trace::MeasureClockOverhead() { 183 if (UseThreadCpuClock()) { 184 Thread::Current()->GetCpuMicroTime(); 185 } 186 if (UseWallClock()) { 187 MicroTime(); 188 } 189} 190 191// Compute an average time taken to measure clocks. 192uint32_t Trace::GetClockOverheadNanoSeconds() { 193 Thread* self = Thread::Current(); 194 uint64_t start = self->GetCpuMicroTime(); 195 196 for (int i = 4000; i > 0; i--) { 197 MeasureClockOverhead(); 198 MeasureClockOverhead(); 199 MeasureClockOverhead(); 200 MeasureClockOverhead(); 201 MeasureClockOverhead(); 202 MeasureClockOverhead(); 203 MeasureClockOverhead(); 204 MeasureClockOverhead(); 205 } 206 207 uint64_t elapsed_us = self->GetCpuMicroTime() - start; 208 return static_cast<uint32_t>(elapsed_us / 32); 209} 210 211// TODO: put this somewhere with the big-endian equivalent used by JDWP. 212static void Append2LE(uint8_t* buf, uint16_t val) { 213 *buf++ = static_cast<uint8_t>(val); 214 *buf++ = static_cast<uint8_t>(val >> 8); 215} 216 217// TODO: put this somewhere with the big-endian equivalent used by JDWP. 218static void Append4LE(uint8_t* buf, uint32_t val) { 219 *buf++ = static_cast<uint8_t>(val); 220 *buf++ = static_cast<uint8_t>(val >> 8); 221 *buf++ = static_cast<uint8_t>(val >> 16); 222 *buf++ = static_cast<uint8_t>(val >> 24); 223} 224 225// TODO: put this somewhere with the big-endian equivalent used by JDWP. 226static void Append8LE(uint8_t* buf, uint64_t val) { 227 *buf++ = static_cast<uint8_t>(val); 228 *buf++ = static_cast<uint8_t>(val >> 8); 229 *buf++ = static_cast<uint8_t>(val >> 16); 230 *buf++ = static_cast<uint8_t>(val >> 24); 231 *buf++ = static_cast<uint8_t>(val >> 32); 232 *buf++ = static_cast<uint8_t>(val >> 40); 233 *buf++ = static_cast<uint8_t>(val >> 48); 234 *buf++ = static_cast<uint8_t>(val >> 56); 235} 236 237static void GetSample(Thread* thread, void* arg) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 238 BuildStackTraceVisitor build_trace_visitor(thread); 239 build_trace_visitor.WalkStack(); 240 std::vector<mirror::ArtMethod*>* stack_trace = build_trace_visitor.GetStackTrace(); 241 Trace* the_trace = reinterpret_cast<Trace*>(arg); 242 the_trace->CompareAndUpdateStackTrace(thread, stack_trace); 243} 244 245static void ClearThreadStackTraceAndClockBase(Thread* thread, void* arg) { 246 thread->SetTraceClockBase(0); 247 std::vector<mirror::ArtMethod*>* stack_trace = thread->GetStackTraceSample(); 248 thread->SetStackTraceSample(NULL); 249 delete stack_trace; 250} 251 252void Trace::CompareAndUpdateStackTrace(Thread* thread, 253 std::vector<mirror::ArtMethod*>* stack_trace) { 254 CHECK_EQ(pthread_self(), sampling_pthread_); 255 std::vector<mirror::ArtMethod*>* old_stack_trace = thread->GetStackTraceSample(); 256 // Update the thread's stack trace sample. 257 thread->SetStackTraceSample(stack_trace); 258 // Read timer clocks to use for all events in this trace. 259 uint32_t thread_clock_diff = 0; 260 uint32_t wall_clock_diff = 0; 261 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 262 if (old_stack_trace == NULL) { 263 // If there's no previous stack trace sample for this thread, log an entry event for all 264 // methods in the trace. 265 for (std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); 266 rit != stack_trace->rend(); ++rit) { 267 LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered, 268 thread_clock_diff, wall_clock_diff); 269 } 270 } else { 271 // If there's a previous stack trace for this thread, diff the traces and emit entry and exit 272 // events accordingly. 273 std::vector<mirror::ArtMethod*>::reverse_iterator old_rit = old_stack_trace->rbegin(); 274 std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); 275 // Iterate bottom-up over both traces until there's a difference between them. 276 while (old_rit != old_stack_trace->rend() && rit != stack_trace->rend() && *old_rit == *rit) { 277 old_rit++; 278 rit++; 279 } 280 // Iterate top-down over the old trace until the point where they differ, emitting exit events. 281 for (std::vector<mirror::ArtMethod*>::iterator old_it = old_stack_trace->begin(); 282 old_it != old_rit.base(); ++old_it) { 283 LogMethodTraceEvent(thread, *old_it, instrumentation::Instrumentation::kMethodExited, 284 thread_clock_diff, wall_clock_diff); 285 } 286 // Iterate bottom-up over the new trace from the point where they differ, emitting entry events. 287 for (; rit != stack_trace->rend(); ++rit) { 288 LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered, 289 thread_clock_diff, wall_clock_diff); 290 } 291 FreeStackTrace(old_stack_trace); 292 } 293} 294 295void* Trace::RunSamplingThread(void* arg) { 296 Runtime* runtime = Runtime::Current(); 297 intptr_t interval_us = reinterpret_cast<intptr_t>(arg); 298 CHECK_GE(interval_us, 0); 299 CHECK(runtime->AttachCurrentThread("Sampling Profiler", true, runtime->GetSystemThreadGroup(), 300 !runtime->IsCompiler())); 301 302 while (true) { 303 usleep(interval_us); 304 ATRACE_BEGIN("Profile sampling"); 305 Thread* self = Thread::Current(); 306 Trace* the_trace; 307 { 308 MutexLock mu(self, *Locks::trace_lock_); 309 the_trace = the_trace_; 310 if (the_trace == NULL) { 311 break; 312 } 313 } 314 315 runtime->GetThreadList()->SuspendAll(); 316 { 317 MutexLock mu(self, *Locks::thread_list_lock_); 318 runtime->GetThreadList()->ForEach(GetSample, the_trace); 319 } 320 runtime->GetThreadList()->ResumeAll(); 321 ATRACE_END(); 322 } 323 324 runtime->DetachCurrentThread(); 325 return NULL; 326} 327 328void Trace::Start(const char* trace_filename, int trace_fd, int buffer_size, int flags, 329 bool direct_to_ddms, bool sampling_enabled, int interval_us) { 330 Thread* self = Thread::Current(); 331 { 332 MutexLock mu(self, *Locks::trace_lock_); 333 if (the_trace_ != NULL) { 334 LOG(ERROR) << "Trace already in progress, ignoring this request"; 335 return; 336 } 337 } 338 Runtime* runtime = Runtime::Current(); 339 runtime->GetThreadList()->SuspendAll(); 340 341 // Open trace file if not going directly to ddms. 342 std::unique_ptr<File> trace_file; 343 if (!direct_to_ddms) { 344 if (trace_fd < 0) { 345 trace_file.reset(OS::CreateEmptyFile(trace_filename)); 346 } else { 347 trace_file.reset(new File(trace_fd, "tracefile")); 348 trace_file->DisableAutoClose(); 349 } 350 if (trace_file.get() == NULL) { 351 PLOG(ERROR) << "Unable to open trace file '" << trace_filename << "'"; 352 runtime->GetThreadList()->ResumeAll(); 353 ScopedObjectAccess soa(self); 354 ThrowRuntimeException("Unable to open trace file '%s'", trace_filename); 355 return; 356 } 357 } 358 359 // Create Trace object. 360 { 361 MutexLock mu(self, *Locks::trace_lock_); 362 if (the_trace_ != NULL) { 363 LOG(ERROR) << "Trace already in progress, ignoring this request"; 364 } else { 365 the_trace_ = new Trace(trace_file.release(), buffer_size, flags, sampling_enabled); 366 367 // Enable count of allocs if specified in the flags. 368 if ((flags && kTraceCountAllocs) != 0) { 369 runtime->SetStatsEnabled(true); 370 } 371 372 373 374 if (sampling_enabled) { 375 CHECK_PTHREAD_CALL(pthread_create, (&sampling_pthread_, NULL, &RunSamplingThread, 376 reinterpret_cast<void*>(interval_us)), 377 "Sampling profiler thread"); 378 } else { 379 runtime->GetInstrumentation()->AddListener(the_trace_, 380 instrumentation::Instrumentation::kMethodEntered | 381 instrumentation::Instrumentation::kMethodExited | 382 instrumentation::Instrumentation::kMethodUnwind); 383 runtime->GetInstrumentation()->EnableMethodTracing(); 384 } 385 } 386 } 387 runtime->GetThreadList()->ResumeAll(); 388} 389 390void Trace::Stop() { 391 Runtime* runtime = Runtime::Current(); 392 runtime->GetThreadList()->SuspendAll(); 393 Trace* the_trace = NULL; 394 pthread_t sampling_pthread = 0U; 395 { 396 MutexLock mu(Thread::Current(), *Locks::trace_lock_); 397 if (the_trace_ == NULL) { 398 LOG(ERROR) << "Trace stop requested, but no trace currently running"; 399 } else { 400 the_trace = the_trace_; 401 the_trace_ = NULL; 402 sampling_pthread = sampling_pthread_; 403 sampling_pthread_ = 0U; 404 } 405 } 406 if (the_trace != NULL) { 407 the_trace->FinishTracing(); 408 409 if (the_trace->sampling_enabled_) { 410 MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); 411 runtime->GetThreadList()->ForEach(ClearThreadStackTraceAndClockBase, NULL); 412 } else { 413 runtime->GetInstrumentation()->DisableMethodTracing(); 414 runtime->GetInstrumentation()->RemoveListener(the_trace, 415 instrumentation::Instrumentation::kMethodEntered | 416 instrumentation::Instrumentation::kMethodExited | 417 instrumentation::Instrumentation::kMethodUnwind); 418 } 419 delete the_trace; 420 } 421 runtime->GetThreadList()->ResumeAll(); 422 423 if (sampling_pthread != 0U) { 424 CHECK_PTHREAD_CALL(pthread_join, (sampling_pthread, NULL), "sampling thread shutdown"); 425 } 426} 427 428void Trace::Shutdown() { 429 if (GetMethodTracingMode() != kTracingInactive) { 430 Stop(); 431 } 432} 433 434TracingMode Trace::GetMethodTracingMode() { 435 MutexLock mu(Thread::Current(), *Locks::trace_lock_); 436 if (the_trace_ == NULL) { 437 return kTracingInactive; 438 } else if (the_trace_->sampling_enabled_) { 439 return kSampleProfilingActive; 440 } else { 441 return kMethodTracingActive; 442 } 443} 444 445Trace::Trace(File* trace_file, int buffer_size, int flags, bool sampling_enabled) 446 : trace_file_(trace_file), buf_(new uint8_t[buffer_size]()), flags_(flags), 447 sampling_enabled_(sampling_enabled), clock_source_(default_clock_source_), 448 buffer_size_(buffer_size), start_time_(MicroTime()), 449 clock_overhead_ns_(GetClockOverheadNanoSeconds()), cur_offset_(0), overflow_(false) { 450 // Set up the beginning of the trace. 451 uint16_t trace_version = GetTraceVersion(clock_source_); 452 memset(buf_.get(), 0, kTraceHeaderLength); 453 Append4LE(buf_.get(), kTraceMagicValue); 454 Append2LE(buf_.get() + 4, trace_version); 455 Append2LE(buf_.get() + 6, kTraceHeaderLength); 456 Append8LE(buf_.get() + 8, start_time_); 457 if (trace_version >= kTraceVersionDualClock) { 458 uint16_t record_size = GetRecordSize(clock_source_); 459 Append2LE(buf_.get() + 16, record_size); 460 } 461 462 // Update current offset. 463 cur_offset_.StoreRelaxed(kTraceHeaderLength); 464} 465 466static void DumpBuf(uint8_t* buf, size_t buf_size, ProfilerClockSource clock_source) 467 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 468 uint8_t* ptr = buf + kTraceHeaderLength; 469 uint8_t* end = buf + buf_size; 470 471 while (ptr < end) { 472 uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); 473 mirror::ArtMethod* method = DecodeTraceMethodId(tmid); 474 TraceAction action = DecodeTraceAction(tmid); 475 LOG(INFO) << PrettyMethod(method) << " " << static_cast<int>(action); 476 ptr += GetRecordSize(clock_source); 477 } 478} 479 480void Trace::FinishTracing() { 481 // Compute elapsed time. 482 uint64_t elapsed = MicroTime() - start_time_; 483 484 size_t final_offset = cur_offset_.LoadRelaxed(); 485 486 if ((flags_ & kTraceCountAllocs) != 0) { 487 Runtime::Current()->SetStatsEnabled(false); 488 } 489 490 std::set<mirror::ArtMethod*> visited_methods; 491 GetVisitedMethods(final_offset, &visited_methods); 492 493 std::ostringstream os; 494 495 os << StringPrintf("%cversion\n", kTraceTokenChar); 496 os << StringPrintf("%d\n", GetTraceVersion(clock_source_)); 497 os << StringPrintf("data-file-overflow=%s\n", overflow_ ? "true" : "false"); 498 if (UseThreadCpuClock()) { 499 if (UseWallClock()) { 500 os << StringPrintf("clock=dual\n"); 501 } else { 502 os << StringPrintf("clock=thread-cpu\n"); 503 } 504 } else { 505 os << StringPrintf("clock=wall\n"); 506 } 507 os << StringPrintf("elapsed-time-usec=%" PRIu64 "\n", elapsed); 508 size_t num_records = (final_offset - kTraceHeaderLength) / GetRecordSize(clock_source_); 509 os << StringPrintf("num-method-calls=%zd\n", num_records); 510 os << StringPrintf("clock-call-overhead-nsec=%d\n", clock_overhead_ns_); 511 os << StringPrintf("vm=art\n"); 512 if ((flags_ & kTraceCountAllocs) != 0) { 513 os << StringPrintf("alloc-count=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_OBJECTS)); 514 os << StringPrintf("alloc-size=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_BYTES)); 515 os << StringPrintf("gc-count=%d\n", Runtime::Current()->GetStat(KIND_GC_INVOCATIONS)); 516 } 517 os << StringPrintf("%cthreads\n", kTraceTokenChar); 518 DumpThreadList(os); 519 os << StringPrintf("%cmethods\n", kTraceTokenChar); 520 DumpMethodList(os, visited_methods); 521 os << StringPrintf("%cend\n", kTraceTokenChar); 522 523 std::string header(os.str()); 524 if (trace_file_.get() == NULL) { 525 iovec iov[2]; 526 iov[0].iov_base = reinterpret_cast<void*>(const_cast<char*>(header.c_str())); 527 iov[0].iov_len = header.length(); 528 iov[1].iov_base = buf_.get(); 529 iov[1].iov_len = final_offset; 530 Dbg::DdmSendChunkV(CHUNK_TYPE("MPSE"), iov, 2); 531 const bool kDumpTraceInfo = false; 532 if (kDumpTraceInfo) { 533 LOG(INFO) << "Trace sent:\n" << header; 534 DumpBuf(buf_.get(), final_offset, clock_source_); 535 } 536 } else { 537 if (!trace_file_->WriteFully(header.c_str(), header.length()) || 538 !trace_file_->WriteFully(buf_.get(), final_offset)) { 539 std::string detail(StringPrintf("Trace data write failed: %s", strerror(errno))); 540 PLOG(ERROR) << detail; 541 ThrowRuntimeException("%s", detail.c_str()); 542 } 543 } 544} 545 546void Trace::DexPcMoved(Thread* thread, mirror::Object* this_object, 547 mirror::ArtMethod* method, uint32_t new_dex_pc) { 548 // We're not recorded to listen to this kind of event, so complain. 549 LOG(ERROR) << "Unexpected dex PC event in tracing " << PrettyMethod(method) << " " << new_dex_pc; 550}; 551 552void Trace::FieldRead(Thread* /*thread*/, mirror::Object* this_object, 553 mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field) 554 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 555 // We're not recorded to listen to this kind of event, so complain. 556 LOG(ERROR) << "Unexpected field read event in tracing " << PrettyMethod(method) << " " << dex_pc; 557} 558 559void Trace::FieldWritten(Thread* /*thread*/, mirror::Object* this_object, 560 mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field, 561 const JValue& field_value) 562 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 563 // We're not recorded to listen to this kind of event, so complain. 564 LOG(ERROR) << "Unexpected field write event in tracing " << PrettyMethod(method) << " " << dex_pc; 565} 566 567void Trace::MethodEntered(Thread* thread, mirror::Object* this_object, 568 mirror::ArtMethod* method, uint32_t dex_pc) { 569 uint32_t thread_clock_diff = 0; 570 uint32_t wall_clock_diff = 0; 571 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 572 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodEntered, 573 thread_clock_diff, wall_clock_diff); 574} 575 576void Trace::MethodExited(Thread* thread, mirror::Object* this_object, 577 mirror::ArtMethod* method, uint32_t dex_pc, 578 const JValue& return_value) { 579 UNUSED(return_value); 580 uint32_t thread_clock_diff = 0; 581 uint32_t wall_clock_diff = 0; 582 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 583 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodExited, 584 thread_clock_diff, wall_clock_diff); 585} 586 587void Trace::MethodUnwind(Thread* thread, mirror::Object* this_object, 588 mirror::ArtMethod* method, uint32_t dex_pc) { 589 uint32_t thread_clock_diff = 0; 590 uint32_t wall_clock_diff = 0; 591 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 592 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodUnwind, 593 thread_clock_diff, wall_clock_diff); 594} 595 596void Trace::ExceptionCaught(Thread* thread, const ThrowLocation& throw_location, 597 mirror::ArtMethod* catch_method, uint32_t catch_dex_pc, 598 mirror::Throwable* exception_object) 599 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 600 LOG(ERROR) << "Unexpected exception caught event in tracing"; 601} 602 603void Trace::ReadClocks(Thread* thread, uint32_t* thread_clock_diff, uint32_t* wall_clock_diff) { 604 if (UseThreadCpuClock()) { 605 uint64_t clock_base = thread->GetTraceClockBase(); 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 } 614 if (UseWallClock()) { 615 *wall_clock_diff = MicroTime() - start_time_; 616 } 617} 618 619void Trace::LogMethodTraceEvent(Thread* thread, mirror::ArtMethod* method, 620 instrumentation::Instrumentation::InstrumentationEvent event, 621 uint32_t thread_clock_diff, uint32_t wall_clock_diff) { 622 // Advance cur_offset_ atomically. 623 int32_t new_offset; 624 int32_t old_offset; 625 do { 626 old_offset = cur_offset_.LoadRelaxed(); 627 new_offset = old_offset + GetRecordSize(clock_source_); 628 if (new_offset > buffer_size_) { 629 overflow_ = true; 630 return; 631 } 632 } while (!cur_offset_.CompareExchangeWeakSequentiallyConsistent(old_offset, new_offset)); 633 634 TraceAction action = kTraceMethodEnter; 635 switch (event) { 636 case instrumentation::Instrumentation::kMethodEntered: 637 action = kTraceMethodEnter; 638 break; 639 case instrumentation::Instrumentation::kMethodExited: 640 action = kTraceMethodExit; 641 break; 642 case instrumentation::Instrumentation::kMethodUnwind: 643 action = kTraceUnroll; 644 break; 645 default: 646 UNIMPLEMENTED(FATAL) << "Unexpected event: " << event; 647 } 648 649 uint32_t method_value = EncodeTraceMethodAndAction(method, action); 650 651 // Write data 652 uint8_t* ptr = buf_.get() + old_offset; 653 Append2LE(ptr, thread->GetTid()); 654 Append4LE(ptr + 2, method_value); 655 ptr += 6; 656 657 if (UseThreadCpuClock()) { 658 Append4LE(ptr, thread_clock_diff); 659 ptr += 4; 660 } 661 if (UseWallClock()) { 662 Append4LE(ptr, wall_clock_diff); 663 } 664} 665 666void Trace::GetVisitedMethods(size_t buf_size, 667 std::set<mirror::ArtMethod*>* visited_methods) { 668 uint8_t* ptr = buf_.get() + kTraceHeaderLength; 669 uint8_t* end = buf_.get() + buf_size; 670 671 while (ptr < end) { 672 uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); 673 mirror::ArtMethod* method = DecodeTraceMethodId(tmid); 674 visited_methods->insert(method); 675 ptr += GetRecordSize(clock_source_); 676 } 677} 678 679void Trace::DumpMethodList(std::ostream& os, const std::set<mirror::ArtMethod*>& visited_methods) { 680 for (const auto& method : visited_methods) { 681 os << StringPrintf("%p\t%s\t%s\t%s\t%s\n", method, 682 PrettyDescriptor(method->GetDeclaringClassDescriptor()).c_str(), method->GetName(), 683 method->GetSignature().ToString().c_str(), method->GetDeclaringClassSourceFile()); 684 } 685} 686 687static void DumpThread(Thread* t, void* arg) { 688 std::ostream& os = *reinterpret_cast<std::ostream*>(arg); 689 std::string name; 690 t->GetThreadName(name); 691 os << t->GetTid() << "\t" << name << "\n"; 692} 693 694void Trace::DumpThreadList(std::ostream& os) { 695 Thread* self = Thread::Current(); 696 Locks::thread_list_lock_->AssertNotHeld(self); 697 MutexLock mu(self, *Locks::thread_list_lock_); 698 Runtime::Current()->GetThreadList()->ForEach(DumpThread, &os); 699} 700 701} // namespace art 702