trace.cc revision f8bdd4e783842577e49f418a0b5962ba49dfdd93
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 "os.h" 34#include "scoped_thread_state_change.h" 35#include "ScopedLocalRef.h" 36#include "thread.h" 37#include "thread_list.h" 38#if !defined(ART_USE_PORTABLE_COMPILER) 39#include "entrypoints/quick/quick_entrypoints.h" 40#endif 41 42namespace art { 43 44// File format: 45// header 46// record 0 47// record 1 48// ... 49// 50// Header format: 51// u4 magic ('SLOW') 52// u2 version 53// u2 offset to data 54// u8 start date/time in usec 55// u2 record size in bytes (version >= 2 only) 56// ... padding to 32 bytes 57// 58// Record format v1: 59// u1 thread ID 60// u4 method ID | method action 61// u4 time delta since start, in usec 62// 63// Record format v2: 64// u2 thread ID 65// u4 method ID | method action 66// u4 time delta since start, in usec 67// 68// Record format v3: 69// u2 thread ID 70// u4 method ID | method action 71// u4 time delta since start, in usec 72// u4 wall time since start, in usec (when clock == "dual" only) 73// 74// 32 bits of microseconds is 70 minutes. 75// 76// All values are stored in little-endian order. 77 78enum TraceAction { 79 kTraceMethodEnter = 0x00, // method entry 80 kTraceMethodExit = 0x01, // method exit 81 kTraceUnroll = 0x02, // method exited by exception unrolling 82 // 0x03 currently unused 83 kTraceMethodActionMask = 0x03, // two bits 84}; 85 86class BuildStackTraceVisitor : public StackVisitor { 87 public: 88 explicit BuildStackTraceVisitor(Thread* thread) : StackVisitor(thread, NULL), 89 method_trace_(Trace::AllocStackTrace()) {} 90 91 bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 92 mirror::ArtMethod* m = GetMethod(); 93 // Ignore runtime frames (in particular callee save). 94 if (!m->IsRuntimeMethod()) { 95 method_trace_->push_back(m); 96 } 97 return true; 98 } 99 100 // Returns a stack trace where the topmost frame corresponds with the first element of the vector. 101 std::vector<mirror::ArtMethod*>* GetStackTrace() const { 102 return method_trace_; 103 } 104 105 private: 106 std::vector<mirror::ArtMethod*>* const method_trace_; 107}; 108 109static const char kTraceTokenChar = '*'; 110static const uint16_t kTraceHeaderLength = 32; 111static const uint32_t kTraceMagicValue = 0x574f4c53; 112static const uint16_t kTraceVersionSingleClock = 2; 113static const uint16_t kTraceVersionDualClock = 3; 114static const uint16_t kTraceRecordSizeSingleClock = 10; // using v2 115static const uint16_t kTraceRecordSizeDualClock = 14; // using v3 with two timestamps 116 117TraceClockSource Trace::default_clock_source_ = kDefaultTraceClockSource; 118 119Trace* volatile Trace::the_trace_ = NULL; 120pthread_t Trace::sampling_pthread_ = 0U; 121std::unique_ptr<std::vector<mirror::ArtMethod*>> Trace::temp_stack_trace_; 122 123static mirror::ArtMethod* DecodeTraceMethodId(uint32_t tmid) { 124 return reinterpret_cast<mirror::ArtMethod*>(tmid & ~kTraceMethodActionMask); 125} 126 127static TraceAction DecodeTraceAction(uint32_t tmid) { 128 return static_cast<TraceAction>(tmid & kTraceMethodActionMask); 129} 130 131static uint32_t EncodeTraceMethodAndAction(mirror::ArtMethod* method, 132 TraceAction action) { 133 uint32_t tmid = PointerToLowMemUInt32(method) | action; 134 DCHECK_EQ(method, DecodeTraceMethodId(tmid)); 135 return tmid; 136} 137 138std::vector<mirror::ArtMethod*>* Trace::AllocStackTrace() { 139 if (temp_stack_trace_.get() != NULL) { 140 return temp_stack_trace_.release(); 141 } else { 142 return new std::vector<mirror::ArtMethod*>(); 143 } 144} 145 146void Trace::FreeStackTrace(std::vector<mirror::ArtMethod*>* stack_trace) { 147 stack_trace->clear(); 148 temp_stack_trace_.reset(stack_trace); 149} 150 151void Trace::SetDefaultClockSource(TraceClockSource clock_source) { 152#if defined(HAVE_POSIX_CLOCKS) 153 default_clock_source_ = clock_source; 154#else 155 if (clock_source != kTraceClockSourceWall) { 156 LOG(WARNING) << "Ignoring tracing request to use CPU time."; 157 } 158#endif 159} 160 161static uint16_t GetTraceVersion(TraceClockSource clock_source) { 162 return (clock_source == kTraceClockSourceDual) ? kTraceVersionDualClock 163 : kTraceVersionSingleClock; 164} 165 166static uint16_t GetRecordSize(TraceClockSource clock_source) { 167 return (clock_source == kTraceClockSourceDual) ? kTraceRecordSizeDualClock 168 : kTraceRecordSizeSingleClock; 169} 170 171bool Trace::UseThreadCpuClock() { 172 return (clock_source_ == kTraceClockSourceThreadCpu) || 173 (clock_source_ == kTraceClockSourceDual); 174} 175 176bool Trace::UseWallClock() { 177 return (clock_source_ == kTraceClockSourceWall) || 178 (clock_source_ == kTraceClockSourceDual); 179} 180 181void Trace::MeasureClockOverhead() { 182 if (UseThreadCpuClock()) { 183 Thread::Current()->GetCpuMicroTime(); 184 } 185 if (UseWallClock()) { 186 MicroTime(); 187 } 188} 189 190// Compute an average time taken to measure clocks. 191uint32_t Trace::GetClockOverheadNanoSeconds() { 192 Thread* self = Thread::Current(); 193 uint64_t start = self->GetCpuMicroTime(); 194 195 for (int i = 4000; i > 0; i--) { 196 MeasureClockOverhead(); 197 MeasureClockOverhead(); 198 MeasureClockOverhead(); 199 MeasureClockOverhead(); 200 MeasureClockOverhead(); 201 MeasureClockOverhead(); 202 MeasureClockOverhead(); 203 MeasureClockOverhead(); 204 } 205 206 uint64_t elapsed_us = self->GetCpuMicroTime() - start; 207 return static_cast<uint32_t>(elapsed_us / 32); 208} 209 210// TODO: put this somewhere with the big-endian equivalent used by JDWP. 211static void Append2LE(uint8_t* buf, uint16_t val) { 212 *buf++ = static_cast<uint8_t>(val); 213 *buf++ = static_cast<uint8_t>(val >> 8); 214} 215 216// TODO: put this somewhere with the big-endian equivalent used by JDWP. 217static void Append4LE(uint8_t* buf, uint32_t val) { 218 *buf++ = static_cast<uint8_t>(val); 219 *buf++ = static_cast<uint8_t>(val >> 8); 220 *buf++ = static_cast<uint8_t>(val >> 16); 221 *buf++ = static_cast<uint8_t>(val >> 24); 222} 223 224// TODO: put this somewhere with the big-endian equivalent used by JDWP. 225static void Append8LE(uint8_t* buf, uint64_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 *buf++ = static_cast<uint8_t>(val >> 32); 231 *buf++ = static_cast<uint8_t>(val >> 40); 232 *buf++ = static_cast<uint8_t>(val >> 48); 233 *buf++ = static_cast<uint8_t>(val >> 56); 234} 235 236static void GetSample(Thread* thread, void* arg) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 237 BuildStackTraceVisitor build_trace_visitor(thread); 238 build_trace_visitor.WalkStack(); 239 std::vector<mirror::ArtMethod*>* stack_trace = build_trace_visitor.GetStackTrace(); 240 Trace* the_trace = reinterpret_cast<Trace*>(arg); 241 the_trace->CompareAndUpdateStackTrace(thread, stack_trace); 242} 243 244static void ClearThreadStackTraceAndClockBase(Thread* thread, void* arg) { 245 thread->SetTraceClockBase(0); 246 std::vector<mirror::ArtMethod*>* stack_trace = thread->GetStackTraceSample(); 247 thread->SetStackTraceSample(NULL); 248 delete stack_trace; 249} 250 251void Trace::CompareAndUpdateStackTrace(Thread* thread, 252 std::vector<mirror::ArtMethod*>* stack_trace) { 253 CHECK_EQ(pthread_self(), sampling_pthread_); 254 std::vector<mirror::ArtMethod*>* old_stack_trace = thread->GetStackTraceSample(); 255 // Update the thread's stack trace sample. 256 thread->SetStackTraceSample(stack_trace); 257 // Read timer clocks to use for all events in this trace. 258 uint32_t thread_clock_diff = 0; 259 uint32_t wall_clock_diff = 0; 260 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 261 if (old_stack_trace == NULL) { 262 // If there's no previous stack trace sample for this thread, log an entry event for all 263 // methods in the trace. 264 for (std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); 265 rit != stack_trace->rend(); ++rit) { 266 LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered, 267 thread_clock_diff, wall_clock_diff); 268 } 269 } else { 270 // If there's a previous stack trace for this thread, diff the traces and emit entry and exit 271 // events accordingly. 272 std::vector<mirror::ArtMethod*>::reverse_iterator old_rit = old_stack_trace->rbegin(); 273 std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); 274 // Iterate bottom-up over both traces until there's a difference between them. 275 while (old_rit != old_stack_trace->rend() && rit != stack_trace->rend() && *old_rit == *rit) { 276 old_rit++; 277 rit++; 278 } 279 // Iterate top-down over the old trace until the point where they differ, emitting exit events. 280 for (std::vector<mirror::ArtMethod*>::iterator old_it = old_stack_trace->begin(); 281 old_it != old_rit.base(); ++old_it) { 282 LogMethodTraceEvent(thread, *old_it, instrumentation::Instrumentation::kMethodExited, 283 thread_clock_diff, wall_clock_diff); 284 } 285 // Iterate bottom-up over the new trace from the point where they differ, emitting entry events. 286 for (; rit != stack_trace->rend(); ++rit) { 287 LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered, 288 thread_clock_diff, wall_clock_diff); 289 } 290 FreeStackTrace(old_stack_trace); 291 } 292} 293 294void* Trace::RunSamplingThread(void* arg) { 295 Runtime* runtime = Runtime::Current(); 296 intptr_t interval_us = reinterpret_cast<intptr_t>(arg); 297 CHECK_GE(interval_us, 0); 298 CHECK(runtime->AttachCurrentThread("Sampling Profiler", true, runtime->GetSystemThreadGroup(), 299 !runtime->IsCompiler())); 300 301 while (true) { 302 usleep(interval_us); 303 ATRACE_BEGIN("Profile sampling"); 304 Thread* self = Thread::Current(); 305 Trace* the_trace; 306 { 307 MutexLock mu(self, *Locks::trace_lock_); 308 the_trace = the_trace_; 309 if (the_trace == NULL) { 310 break; 311 } 312 } 313 314 runtime->GetThreadList()->SuspendAll(); 315 { 316 MutexLock mu(self, *Locks::thread_list_lock_); 317 runtime->GetThreadList()->ForEach(GetSample, the_trace); 318 } 319 runtime->GetThreadList()->ResumeAll(); 320 ATRACE_END(); 321 } 322 323 runtime->DetachCurrentThread(); 324 return NULL; 325} 326 327void Trace::Start(const char* trace_filename, int trace_fd, int buffer_size, int flags, 328 bool direct_to_ddms, bool sampling_enabled, int interval_us) { 329 Thread* self = Thread::Current(); 330 { 331 MutexLock mu(self, *Locks::trace_lock_); 332 if (the_trace_ != NULL) { 333 LOG(ERROR) << "Trace already in progress, ignoring this request"; 334 return; 335 } 336 } 337 338 // Check interval if sampling is enabled 339 if (sampling_enabled && interval_us <= 0) { 340 LOG(ERROR) << "Invalid sampling interval: " << interval_us; 341 ScopedObjectAccess soa(self); 342 ThrowRuntimeException("Invalid sampling interval: %d", interval_us); 343 return; 344 } 345 346 // Open trace file if not going directly to ddms. 347 std::unique_ptr<File> trace_file; 348 if (!direct_to_ddms) { 349 if (trace_fd < 0) { 350 trace_file.reset(OS::CreateEmptyFile(trace_filename)); 351 } else { 352 trace_file.reset(new File(trace_fd, "tracefile")); 353 trace_file->DisableAutoClose(); 354 } 355 if (trace_file.get() == NULL) { 356 PLOG(ERROR) << "Unable to open trace file '" << trace_filename << "'"; 357 ScopedObjectAccess soa(self); 358 ThrowRuntimeException("Unable to open trace file '%s'", trace_filename); 359 return; 360 } 361 } 362 363 Runtime* runtime = Runtime::Current(); 364 runtime->GetThreadList()->SuspendAll(); 365 366 // Create Trace object. 367 { 368 MutexLock mu(self, *Locks::trace_lock_); 369 if (the_trace_ != NULL) { 370 LOG(ERROR) << "Trace already in progress, ignoring this request"; 371 } else { 372 the_trace_ = new Trace(trace_file.release(), buffer_size, flags, sampling_enabled); 373 374 // Enable count of allocs if specified in the flags. 375 if ((flags && kTraceCountAllocs) != 0) { 376 runtime->SetStatsEnabled(true); 377 } 378 379 380 381 if (sampling_enabled) { 382 CHECK_PTHREAD_CALL(pthread_create, (&sampling_pthread_, NULL, &RunSamplingThread, 383 reinterpret_cast<void*>(interval_us)), 384 "Sampling profiler thread"); 385 } else { 386 runtime->GetInstrumentation()->AddListener(the_trace_, 387 instrumentation::Instrumentation::kMethodEntered | 388 instrumentation::Instrumentation::kMethodExited | 389 instrumentation::Instrumentation::kMethodUnwind); 390 runtime->GetInstrumentation()->EnableMethodTracing(); 391 } 392 } 393 } 394 395 runtime->GetThreadList()->ResumeAll(); 396} 397 398void Trace::Stop() { 399 Runtime* runtime = Runtime::Current(); 400 runtime->GetThreadList()->SuspendAll(); 401 Trace* the_trace = NULL; 402 pthread_t sampling_pthread = 0U; 403 { 404 MutexLock mu(Thread::Current(), *Locks::trace_lock_); 405 if (the_trace_ == NULL) { 406 LOG(ERROR) << "Trace stop requested, but no trace currently running"; 407 } else { 408 the_trace = the_trace_; 409 the_trace_ = NULL; 410 sampling_pthread = sampling_pthread_; 411 } 412 } 413 if (the_trace != NULL) { 414 the_trace->FinishTracing(); 415 416 if (the_trace->sampling_enabled_) { 417 MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); 418 runtime->GetThreadList()->ForEach(ClearThreadStackTraceAndClockBase, NULL); 419 } else { 420 runtime->GetInstrumentation()->DisableMethodTracing(); 421 runtime->GetInstrumentation()->RemoveListener(the_trace, 422 instrumentation::Instrumentation::kMethodEntered | 423 instrumentation::Instrumentation::kMethodExited | 424 instrumentation::Instrumentation::kMethodUnwind); 425 } 426 delete the_trace; 427 } 428 runtime->GetThreadList()->ResumeAll(); 429 430 if (sampling_pthread != 0U) { 431 CHECK_PTHREAD_CALL(pthread_join, (sampling_pthread, NULL), "sampling thread shutdown"); 432 sampling_pthread_ = 0U; 433 } 434} 435 436void Trace::Shutdown() { 437 if (GetMethodTracingMode() != kTracingInactive) { 438 Stop(); 439 } 440} 441 442TracingMode Trace::GetMethodTracingMode() { 443 MutexLock mu(Thread::Current(), *Locks::trace_lock_); 444 if (the_trace_ == NULL) { 445 return kTracingInactive; 446 } else if (the_trace_->sampling_enabled_) { 447 return kSampleProfilingActive; 448 } else { 449 return kMethodTracingActive; 450 } 451} 452 453Trace::Trace(File* trace_file, int buffer_size, int flags, bool sampling_enabled) 454 : trace_file_(trace_file), buf_(new uint8_t[buffer_size]()), flags_(flags), 455 sampling_enabled_(sampling_enabled), clock_source_(default_clock_source_), 456 buffer_size_(buffer_size), start_time_(MicroTime()), 457 clock_overhead_ns_(GetClockOverheadNanoSeconds()), cur_offset_(0), overflow_(false) { 458 // Set up the beginning of the trace. 459 uint16_t trace_version = GetTraceVersion(clock_source_); 460 memset(buf_.get(), 0, kTraceHeaderLength); 461 Append4LE(buf_.get(), kTraceMagicValue); 462 Append2LE(buf_.get() + 4, trace_version); 463 Append2LE(buf_.get() + 6, kTraceHeaderLength); 464 Append8LE(buf_.get() + 8, start_time_); 465 if (trace_version >= kTraceVersionDualClock) { 466 uint16_t record_size = GetRecordSize(clock_source_); 467 Append2LE(buf_.get() + 16, record_size); 468 } 469 470 // Update current offset. 471 cur_offset_.StoreRelaxed(kTraceHeaderLength); 472} 473 474static void DumpBuf(uint8_t* buf, size_t buf_size, TraceClockSource clock_source) 475 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 476 uint8_t* ptr = buf + kTraceHeaderLength; 477 uint8_t* end = buf + buf_size; 478 479 while (ptr < end) { 480 uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); 481 mirror::ArtMethod* method = DecodeTraceMethodId(tmid); 482 TraceAction action = DecodeTraceAction(tmid); 483 LOG(INFO) << PrettyMethod(method) << " " << static_cast<int>(action); 484 ptr += GetRecordSize(clock_source); 485 } 486} 487 488void Trace::FinishTracing() { 489 // Compute elapsed time. 490 uint64_t elapsed = MicroTime() - start_time_; 491 492 size_t final_offset = cur_offset_.LoadRelaxed(); 493 494 if ((flags_ & kTraceCountAllocs) != 0) { 495 Runtime::Current()->SetStatsEnabled(false); 496 } 497 498 std::set<mirror::ArtMethod*> visited_methods; 499 GetVisitedMethods(final_offset, &visited_methods); 500 501 std::ostringstream os; 502 503 os << StringPrintf("%cversion\n", kTraceTokenChar); 504 os << StringPrintf("%d\n", GetTraceVersion(clock_source_)); 505 os << StringPrintf("data-file-overflow=%s\n", overflow_ ? "true" : "false"); 506 if (UseThreadCpuClock()) { 507 if (UseWallClock()) { 508 os << StringPrintf("clock=dual\n"); 509 } else { 510 os << StringPrintf("clock=thread-cpu\n"); 511 } 512 } else { 513 os << StringPrintf("clock=wall\n"); 514 } 515 os << StringPrintf("elapsed-time-usec=%" PRIu64 "\n", elapsed); 516 size_t num_records = (final_offset - kTraceHeaderLength) / GetRecordSize(clock_source_); 517 os << StringPrintf("num-method-calls=%zd\n", num_records); 518 os << StringPrintf("clock-call-overhead-nsec=%d\n", clock_overhead_ns_); 519 os << StringPrintf("vm=art\n"); 520 if ((flags_ & kTraceCountAllocs) != 0) { 521 os << StringPrintf("alloc-count=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_OBJECTS)); 522 os << StringPrintf("alloc-size=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_BYTES)); 523 os << StringPrintf("gc-count=%d\n", Runtime::Current()->GetStat(KIND_GC_INVOCATIONS)); 524 } 525 os << StringPrintf("%cthreads\n", kTraceTokenChar); 526 DumpThreadList(os); 527 os << StringPrintf("%cmethods\n", kTraceTokenChar); 528 DumpMethodList(os, visited_methods); 529 os << StringPrintf("%cend\n", kTraceTokenChar); 530 531 std::string header(os.str()); 532 if (trace_file_.get() == NULL) { 533 iovec iov[2]; 534 iov[0].iov_base = reinterpret_cast<void*>(const_cast<char*>(header.c_str())); 535 iov[0].iov_len = header.length(); 536 iov[1].iov_base = buf_.get(); 537 iov[1].iov_len = final_offset; 538 Dbg::DdmSendChunkV(CHUNK_TYPE("MPSE"), iov, 2); 539 const bool kDumpTraceInfo = false; 540 if (kDumpTraceInfo) { 541 LOG(INFO) << "Trace sent:\n" << header; 542 DumpBuf(buf_.get(), final_offset, clock_source_); 543 } 544 } else { 545 if (!trace_file_->WriteFully(header.c_str(), header.length()) || 546 !trace_file_->WriteFully(buf_.get(), final_offset)) { 547 std::string detail(StringPrintf("Trace data write failed: %s", strerror(errno))); 548 PLOG(ERROR) << detail; 549 ThrowRuntimeException("%s", detail.c_str()); 550 } 551 } 552} 553 554void Trace::DexPcMoved(Thread* thread, mirror::Object* this_object, 555 mirror::ArtMethod* method, uint32_t new_dex_pc) { 556 // We're not recorded to listen to this kind of event, so complain. 557 LOG(ERROR) << "Unexpected dex PC event in tracing " << PrettyMethod(method) << " " << new_dex_pc; 558}; 559 560void Trace::FieldRead(Thread* /*thread*/, mirror::Object* this_object, 561 mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field) 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 read event in tracing " << PrettyMethod(method) << " " << dex_pc; 565} 566 567void Trace::FieldWritten(Thread* /*thread*/, mirror::Object* this_object, 568 mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field, 569 const JValue& field_value) 570 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 571 // We're not recorded to listen to this kind of event, so complain. 572 LOG(ERROR) << "Unexpected field write event in tracing " << PrettyMethod(method) << " " << dex_pc; 573} 574 575void Trace::MethodEntered(Thread* thread, mirror::Object* this_object, 576 mirror::ArtMethod* method, uint32_t dex_pc) { 577 uint32_t thread_clock_diff = 0; 578 uint32_t wall_clock_diff = 0; 579 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 580 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodEntered, 581 thread_clock_diff, wall_clock_diff); 582} 583 584void Trace::MethodExited(Thread* thread, mirror::Object* this_object, 585 mirror::ArtMethod* method, uint32_t dex_pc, 586 const JValue& return_value) { 587 UNUSED(return_value); 588 uint32_t thread_clock_diff = 0; 589 uint32_t wall_clock_diff = 0; 590 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 591 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodExited, 592 thread_clock_diff, wall_clock_diff); 593} 594 595void Trace::MethodUnwind(Thread* thread, mirror::Object* this_object, 596 mirror::ArtMethod* method, uint32_t dex_pc) { 597 uint32_t thread_clock_diff = 0; 598 uint32_t wall_clock_diff = 0; 599 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 600 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodUnwind, 601 thread_clock_diff, wall_clock_diff); 602} 603 604void Trace::ExceptionCaught(Thread* thread, const ThrowLocation& throw_location, 605 mirror::ArtMethod* catch_method, uint32_t catch_dex_pc, 606 mirror::Throwable* exception_object) 607 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 608 LOG(ERROR) << "Unexpected exception caught event in tracing"; 609} 610 611void Trace::ReadClocks(Thread* thread, uint32_t* thread_clock_diff, uint32_t* wall_clock_diff) { 612 if (UseThreadCpuClock()) { 613 uint64_t clock_base = thread->GetTraceClockBase(); 614 if (UNLIKELY(clock_base == 0)) { 615 // First event, record the base time in the map. 616 uint64_t time = thread->GetCpuMicroTime(); 617 thread->SetTraceClockBase(time); 618 } else { 619 *thread_clock_diff = thread->GetCpuMicroTime() - clock_base; 620 } 621 } 622 if (UseWallClock()) { 623 *wall_clock_diff = MicroTime() - start_time_; 624 } 625} 626 627void Trace::LogMethodTraceEvent(Thread* thread, mirror::ArtMethod* method, 628 instrumentation::Instrumentation::InstrumentationEvent event, 629 uint32_t thread_clock_diff, uint32_t wall_clock_diff) { 630 // Advance cur_offset_ atomically. 631 int32_t new_offset; 632 int32_t old_offset; 633 do { 634 old_offset = cur_offset_.LoadRelaxed(); 635 new_offset = old_offset + GetRecordSize(clock_source_); 636 if (new_offset > buffer_size_) { 637 overflow_ = true; 638 return; 639 } 640 } while (!cur_offset_.CompareExchangeWeakSequentiallyConsistent(old_offset, new_offset)); 641 642 TraceAction action = kTraceMethodEnter; 643 switch (event) { 644 case instrumentation::Instrumentation::kMethodEntered: 645 action = kTraceMethodEnter; 646 break; 647 case instrumentation::Instrumentation::kMethodExited: 648 action = kTraceMethodExit; 649 break; 650 case instrumentation::Instrumentation::kMethodUnwind: 651 action = kTraceUnroll; 652 break; 653 default: 654 UNIMPLEMENTED(FATAL) << "Unexpected event: " << event; 655 } 656 657 uint32_t method_value = EncodeTraceMethodAndAction(method, action); 658 659 // Write data 660 uint8_t* ptr = buf_.get() + old_offset; 661 Append2LE(ptr, thread->GetTid()); 662 Append4LE(ptr + 2, method_value); 663 ptr += 6; 664 665 if (UseThreadCpuClock()) { 666 Append4LE(ptr, thread_clock_diff); 667 ptr += 4; 668 } 669 if (UseWallClock()) { 670 Append4LE(ptr, wall_clock_diff); 671 } 672} 673 674void Trace::GetVisitedMethods(size_t buf_size, 675 std::set<mirror::ArtMethod*>* visited_methods) { 676 uint8_t* ptr = buf_.get() + kTraceHeaderLength; 677 uint8_t* end = buf_.get() + buf_size; 678 679 while (ptr < end) { 680 uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); 681 mirror::ArtMethod* method = DecodeTraceMethodId(tmid); 682 visited_methods->insert(method); 683 ptr += GetRecordSize(clock_source_); 684 } 685} 686 687void Trace::DumpMethodList(std::ostream& os, const std::set<mirror::ArtMethod*>& visited_methods) { 688 for (const auto& method : visited_methods) { 689 os << StringPrintf("%p\t%s\t%s\t%s\t%s\n", method, 690 PrettyDescriptor(method->GetDeclaringClassDescriptor()).c_str(), method->GetName(), 691 method->GetSignature().ToString().c_str(), method->GetDeclaringClassSourceFile()); 692 } 693} 694 695static void DumpThread(Thread* t, void* arg) { 696 std::ostream& os = *reinterpret_cast<std::ostream*>(arg); 697 std::string name; 698 t->GetThreadName(name); 699 os << t->GetTid() << "\t" << name << "\n"; 700} 701 702void Trace::DumpThreadList(std::ostream& os) { 703 Thread* self = Thread::Current(); 704 Locks::thread_list_lock_->AssertNotHeld(self); 705 MutexLock mu(self, *Locks::thread_list_lock_); 706 Runtime::Current()->GetThreadList()->ForEach(DumpThread, &os); 707} 708 709} // namespace art 710