trace.cc revision 0a18df82f4dea95b7398f8c934341fccbf04eeee
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#define ATRACE_TAG ATRACE_TAG_DALVIK 22#include "cutils/trace.h" 23 24#include "base/stl_util.h" 25#include "base/unix_file/fd_file.h" 26#include "class_linker.h" 27#include "common_throws.h" 28#include "debugger.h" 29#include "dex_file-inl.h" 30#include "instrumentation.h" 31#include "mirror/art_method-inl.h" 32#include "mirror/class-inl.h" 33#include "mirror/dex_cache.h" 34#include "mirror/object_array-inl.h" 35#include "mirror/object-inl.h" 36#include "os.h" 37#include "scoped_thread_state_change.h" 38#include "ScopedLocalRef.h" 39#include "thread.h" 40#include "thread_list.h" 41#include "entrypoints/quick/quick_entrypoints.h" 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 118TraceClockSource Trace::default_clock_source_ = kDefaultTraceClockSource; 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(TraceClockSource clock_source) { 153#if defined(__linux__) 154 default_clock_source_ = clock_source; 155#else 156 if (clock_source != kTraceClockSourceWall) { 157 LOG(WARNING) << "Ignoring tracing request to use CPU time."; 158 } 159#endif 160} 161 162static uint16_t GetTraceVersion(TraceClockSource clock_source) { 163 return (clock_source == kTraceClockSourceDual) ? kTraceVersionDualClock 164 : kTraceVersionSingleClock; 165} 166 167static uint16_t GetRecordSize(TraceClockSource clock_source) { 168 return (clock_source == kTraceClockSourceDual) ? kTraceRecordSizeDualClock 169 : kTraceRecordSizeSingleClock; 170} 171 172bool Trace::UseThreadCpuClock() { 173 return (clock_source_ == kTraceClockSourceThreadCpu) || 174 (clock_source_ == kTraceClockSourceDual); 175} 176 177bool Trace::UseWallClock() { 178 return (clock_source_ == kTraceClockSourceWall) || 179 (clock_source_ == kTraceClockSourceDual); 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 ATTRIBUTE_UNUSED, 246 void* arg ATTRIBUTE_UNUSED) { 247 thread->SetTraceClockBase(0); 248 std::vector<mirror::ArtMethod*>* stack_trace = thread->GetStackTraceSample(); 249 thread->SetStackTraceSample(NULL); 250 delete stack_trace; 251} 252 253void Trace::CompareAndUpdateStackTrace(Thread* thread, 254 std::vector<mirror::ArtMethod*>* stack_trace) { 255 CHECK_EQ(pthread_self(), sampling_pthread_); 256 std::vector<mirror::ArtMethod*>* old_stack_trace = thread->GetStackTraceSample(); 257 // Update the thread's stack trace sample. 258 thread->SetStackTraceSample(stack_trace); 259 // Read timer clocks to use for all events in this trace. 260 uint32_t thread_clock_diff = 0; 261 uint32_t wall_clock_diff = 0; 262 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 263 if (old_stack_trace == NULL) { 264 // If there's no previous stack trace sample for this thread, log an entry event for all 265 // methods in the trace. 266 for (std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); 267 rit != stack_trace->rend(); ++rit) { 268 LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered, 269 thread_clock_diff, wall_clock_diff); 270 } 271 } else { 272 // If there's a previous stack trace for this thread, diff the traces and emit entry and exit 273 // events accordingly. 274 std::vector<mirror::ArtMethod*>::reverse_iterator old_rit = old_stack_trace->rbegin(); 275 std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); 276 // Iterate bottom-up over both traces until there's a difference between them. 277 while (old_rit != old_stack_trace->rend() && rit != stack_trace->rend() && *old_rit == *rit) { 278 old_rit++; 279 rit++; 280 } 281 // Iterate top-down over the old trace until the point where they differ, emitting exit events. 282 for (std::vector<mirror::ArtMethod*>::iterator old_it = old_stack_trace->begin(); 283 old_it != old_rit.base(); ++old_it) { 284 LogMethodTraceEvent(thread, *old_it, instrumentation::Instrumentation::kMethodExited, 285 thread_clock_diff, wall_clock_diff); 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 thread_clock_diff, wall_clock_diff); 291 } 292 FreeStackTrace(old_stack_trace); 293 } 294} 295 296void* Trace::RunSamplingThread(void* arg) { 297 Runtime* runtime = Runtime::Current(); 298 intptr_t interval_us = reinterpret_cast<intptr_t>(arg); 299 CHECK_GE(interval_us, 0); 300 CHECK(runtime->AttachCurrentThread("Sampling Profiler", true, runtime->GetSystemThreadGroup(), 301 !runtime->IsCompiler())); 302 303 while (true) { 304 usleep(interval_us); 305 ATRACE_BEGIN("Profile sampling"); 306 Thread* self = Thread::Current(); 307 Trace* the_trace; 308 { 309 MutexLock mu(self, *Locks::trace_lock_); 310 the_trace = the_trace_; 311 if (the_trace == NULL) { 312 break; 313 } 314 } 315 316 runtime->GetThreadList()->SuspendAll(); 317 { 318 MutexLock mu(self, *Locks::thread_list_lock_); 319 runtime->GetThreadList()->ForEach(GetSample, the_trace); 320 } 321 runtime->GetThreadList()->ResumeAll(); 322 ATRACE_END(); 323 } 324 325 runtime->DetachCurrentThread(); 326 return NULL; 327} 328 329void Trace::Start(const char* trace_filename, int trace_fd, int buffer_size, int flags, 330 bool direct_to_ddms, bool sampling_enabled, int interval_us) { 331 Thread* self = Thread::Current(); 332 { 333 MutexLock mu(self, *Locks::trace_lock_); 334 if (the_trace_ != NULL) { 335 LOG(ERROR) << "Trace already in progress, ignoring this request"; 336 return; 337 } 338 } 339 340 // Check interval if sampling is enabled 341 if (sampling_enabled && interval_us <= 0) { 342 LOG(ERROR) << "Invalid sampling interval: " << interval_us; 343 ScopedObjectAccess soa(self); 344 ThrowRuntimeException("Invalid sampling interval: %d", interval_us); 345 return; 346 } 347 348 // Open trace file if not going directly to ddms. 349 std::unique_ptr<File> trace_file; 350 if (!direct_to_ddms) { 351 if (trace_fd < 0) { 352 trace_file.reset(OS::CreateEmptyFile(trace_filename)); 353 } else { 354 trace_file.reset(new File(trace_fd, "tracefile")); 355 trace_file->DisableAutoClose(); 356 } 357 if (trace_file.get() == NULL) { 358 PLOG(ERROR) << "Unable to open trace file '" << trace_filename << "'"; 359 ScopedObjectAccess soa(self); 360 ThrowRuntimeException("Unable to open trace file '%s'", trace_filename); 361 return; 362 } 363 } 364 365 Runtime* runtime = Runtime::Current(); 366 367 // Enable count of allocs if specified in the flags. 368 bool enable_stats = false; 369 370 runtime->GetThreadList()->SuspendAll(); 371 372 // Create Trace object. 373 { 374 MutexLock mu(self, *Locks::trace_lock_); 375 if (the_trace_ != NULL) { 376 LOG(ERROR) << "Trace already in progress, ignoring this request"; 377 } else { 378 enable_stats = (flags && kTraceCountAllocs) != 0; 379 the_trace_ = new Trace(trace_file.release(), buffer_size, flags, sampling_enabled); 380 if (sampling_enabled) { 381 CHECK_PTHREAD_CALL(pthread_create, (&sampling_pthread_, NULL, &RunSamplingThread, 382 reinterpret_cast<void*>(interval_us)), 383 "Sampling profiler thread"); 384 } else { 385 runtime->GetInstrumentation()->AddListener(the_trace_, 386 instrumentation::Instrumentation::kMethodEntered | 387 instrumentation::Instrumentation::kMethodExited | 388 instrumentation::Instrumentation::kMethodUnwind); 389 runtime->GetInstrumentation()->EnableMethodTracing(); 390 } 391 } 392 } 393 394 runtime->GetThreadList()->ResumeAll(); 395 396 // Can't call this when holding the mutator lock. 397 if (enable_stats) { 398 runtime->SetStatsEnabled(true); 399 } 400} 401 402void Trace::Stop() { 403 bool stop_alloc_counting = false; 404 Runtime* runtime = Runtime::Current(); 405 runtime->GetThreadList()->SuspendAll(); 406 Trace* the_trace = NULL; 407 pthread_t sampling_pthread = 0U; 408 { 409 MutexLock mu(Thread::Current(), *Locks::trace_lock_); 410 if (the_trace_ == NULL) { 411 LOG(ERROR) << "Trace stop requested, but no trace currently running"; 412 } else { 413 the_trace = the_trace_; 414 the_trace_ = NULL; 415 sampling_pthread = sampling_pthread_; 416 } 417 } 418 if (the_trace != NULL) { 419 stop_alloc_counting = (the_trace->flags_ & kTraceCountAllocs) != 0; 420 the_trace->FinishTracing(); 421 422 if (the_trace->sampling_enabled_) { 423 MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); 424 runtime->GetThreadList()->ForEach(ClearThreadStackTraceAndClockBase, NULL); 425 } else { 426 runtime->GetInstrumentation()->DisableMethodTracing(); 427 runtime->GetInstrumentation()->RemoveListener(the_trace, 428 instrumentation::Instrumentation::kMethodEntered | 429 instrumentation::Instrumentation::kMethodExited | 430 instrumentation::Instrumentation::kMethodUnwind); 431 } 432 if (the_trace->trace_file_.get() != nullptr) { 433 // Do not try to erase, so flush and close explicitly. 434 if (the_trace->trace_file_->Flush() != 0) { 435 PLOG(ERROR) << "Could not flush trace file."; 436 } 437 if (the_trace->trace_file_->Close() != 0) { 438 PLOG(ERROR) << "Could not close trace file."; 439 } 440 } 441 delete the_trace; 442 } 443 runtime->GetThreadList()->ResumeAll(); 444 445 if (stop_alloc_counting) { 446 // Can be racy since SetStatsEnabled is not guarded by any locks. 447 Runtime::Current()->SetStatsEnabled(false); 448 } 449 450 if (sampling_pthread != 0U) { 451 CHECK_PTHREAD_CALL(pthread_join, (sampling_pthread, NULL), "sampling thread shutdown"); 452 sampling_pthread_ = 0U; 453 } 454} 455 456void Trace::Shutdown() { 457 if (GetMethodTracingMode() != kTracingInactive) { 458 Stop(); 459 } 460} 461 462TracingMode Trace::GetMethodTracingMode() { 463 MutexLock mu(Thread::Current(), *Locks::trace_lock_); 464 if (the_trace_ == NULL) { 465 return kTracingInactive; 466 } else if (the_trace_->sampling_enabled_) { 467 return kSampleProfilingActive; 468 } else { 469 return kMethodTracingActive; 470 } 471} 472 473Trace::Trace(File* trace_file, int buffer_size, int flags, bool sampling_enabled) 474 : trace_file_(trace_file), buf_(new uint8_t[buffer_size]()), flags_(flags), 475 sampling_enabled_(sampling_enabled), clock_source_(default_clock_source_), 476 buffer_size_(buffer_size), start_time_(MicroTime()), 477 clock_overhead_ns_(GetClockOverheadNanoSeconds()), cur_offset_(0), overflow_(false) { 478 // Set up the beginning of the trace. 479 uint16_t trace_version = GetTraceVersion(clock_source_); 480 memset(buf_.get(), 0, kTraceHeaderLength); 481 Append4LE(buf_.get(), kTraceMagicValue); 482 Append2LE(buf_.get() + 4, trace_version); 483 Append2LE(buf_.get() + 6, kTraceHeaderLength); 484 Append8LE(buf_.get() + 8, start_time_); 485 if (trace_version >= kTraceVersionDualClock) { 486 uint16_t record_size = GetRecordSize(clock_source_); 487 Append2LE(buf_.get() + 16, record_size); 488 } 489 490 // Update current offset. 491 cur_offset_.StoreRelaxed(kTraceHeaderLength); 492} 493 494static void DumpBuf(uint8_t* buf, size_t buf_size, TraceClockSource clock_source) 495 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 496 uint8_t* ptr = buf + kTraceHeaderLength; 497 uint8_t* end = buf + buf_size; 498 499 while (ptr < end) { 500 uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); 501 mirror::ArtMethod* method = DecodeTraceMethodId(tmid); 502 TraceAction action = DecodeTraceAction(tmid); 503 LOG(INFO) << PrettyMethod(method) << " " << static_cast<int>(action); 504 ptr += GetRecordSize(clock_source); 505 } 506} 507 508void Trace::FinishTracing() { 509 // Compute elapsed time. 510 uint64_t elapsed = MicroTime() - start_time_; 511 512 size_t final_offset = cur_offset_.LoadRelaxed(); 513 514 std::set<mirror::ArtMethod*> visited_methods; 515 GetVisitedMethods(final_offset, &visited_methods); 516 517 std::ostringstream os; 518 519 os << StringPrintf("%cversion\n", kTraceTokenChar); 520 os << StringPrintf("%d\n", GetTraceVersion(clock_source_)); 521 os << StringPrintf("data-file-overflow=%s\n", overflow_ ? "true" : "false"); 522 if (UseThreadCpuClock()) { 523 if (UseWallClock()) { 524 os << StringPrintf("clock=dual\n"); 525 } else { 526 os << StringPrintf("clock=thread-cpu\n"); 527 } 528 } else { 529 os << StringPrintf("clock=wall\n"); 530 } 531 os << StringPrintf("elapsed-time-usec=%" PRIu64 "\n", elapsed); 532 size_t num_records = (final_offset - kTraceHeaderLength) / GetRecordSize(clock_source_); 533 os << StringPrintf("num-method-calls=%zd\n", num_records); 534 os << StringPrintf("clock-call-overhead-nsec=%d\n", clock_overhead_ns_); 535 os << StringPrintf("vm=art\n"); 536 if ((flags_ & kTraceCountAllocs) != 0) { 537 os << StringPrintf("alloc-count=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_OBJECTS)); 538 os << StringPrintf("alloc-size=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_BYTES)); 539 os << StringPrintf("gc-count=%d\n", Runtime::Current()->GetStat(KIND_GC_INVOCATIONS)); 540 } 541 os << StringPrintf("%cthreads\n", kTraceTokenChar); 542 DumpThreadList(os); 543 os << StringPrintf("%cmethods\n", kTraceTokenChar); 544 DumpMethodList(os, visited_methods); 545 os << StringPrintf("%cend\n", kTraceTokenChar); 546 547 std::string header(os.str()); 548 if (trace_file_.get() == NULL) { 549 iovec iov[2]; 550 iov[0].iov_base = reinterpret_cast<void*>(const_cast<char*>(header.c_str())); 551 iov[0].iov_len = header.length(); 552 iov[1].iov_base = buf_.get(); 553 iov[1].iov_len = final_offset; 554 Dbg::DdmSendChunkV(CHUNK_TYPE("MPSE"), iov, 2); 555 const bool kDumpTraceInfo = false; 556 if (kDumpTraceInfo) { 557 LOG(INFO) << "Trace sent:\n" << header; 558 DumpBuf(buf_.get(), final_offset, clock_source_); 559 } 560 } else { 561 if (!trace_file_->WriteFully(header.c_str(), header.length()) || 562 !trace_file_->WriteFully(buf_.get(), final_offset)) { 563 std::string detail(StringPrintf("Trace data write failed: %s", strerror(errno))); 564 PLOG(ERROR) << detail; 565 ThrowRuntimeException("%s", detail.c_str()); 566 } 567 } 568} 569 570void Trace::DexPcMoved(Thread* thread, mirror::Object* this_object, 571 mirror::ArtMethod* method, uint32_t new_dex_pc) { 572 UNUSED(thread, this_object, method, new_dex_pc); 573 // We're not recorded to listen to this kind of event, so complain. 574 LOG(ERROR) << "Unexpected dex PC event in tracing " << PrettyMethod(method) << " " << new_dex_pc; 575} 576 577void Trace::FieldRead(Thread* thread, mirror::Object* this_object, 578 mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field) 579 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 580 UNUSED(thread, this_object, method, dex_pc, field); 581 // We're not recorded to listen to this kind of event, so complain. 582 LOG(ERROR) << "Unexpected field read event in tracing " << PrettyMethod(method) << " " << dex_pc; 583} 584 585void Trace::FieldWritten(Thread* thread, mirror::Object* this_object, 586 mirror::ArtMethod* method, uint32_t dex_pc, mirror::ArtField* field, 587 const JValue& field_value) 588 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 589 UNUSED(thread, this_object, method, dex_pc, field, field_value); 590 // We're not recorded to listen to this kind of event, so complain. 591 LOG(ERROR) << "Unexpected field write event in tracing " << PrettyMethod(method) << " " << dex_pc; 592} 593 594void Trace::MethodEntered(Thread* thread, mirror::Object* this_object ATTRIBUTE_UNUSED, 595 mirror::ArtMethod* method, uint32_t dex_pc ATTRIBUTE_UNUSED) { 596 uint32_t thread_clock_diff = 0; 597 uint32_t wall_clock_diff = 0; 598 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 599 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodEntered, 600 thread_clock_diff, wall_clock_diff); 601} 602 603void Trace::MethodExited(Thread* thread, mirror::Object* this_object ATTRIBUTE_UNUSED, 604 mirror::ArtMethod* method, uint32_t dex_pc ATTRIBUTE_UNUSED, 605 const JValue& return_value ATTRIBUTE_UNUSED) { 606 uint32_t thread_clock_diff = 0; 607 uint32_t wall_clock_diff = 0; 608 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 609 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodExited, 610 thread_clock_diff, wall_clock_diff); 611} 612 613void Trace::MethodUnwind(Thread* thread, mirror::Object* this_object ATTRIBUTE_UNUSED, 614 mirror::ArtMethod* method, uint32_t dex_pc ATTRIBUTE_UNUSED) { 615 uint32_t thread_clock_diff = 0; 616 uint32_t wall_clock_diff = 0; 617 ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); 618 LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodUnwind, 619 thread_clock_diff, wall_clock_diff); 620} 621 622void Trace::ExceptionCaught(Thread* thread, const ThrowLocation& throw_location, 623 mirror::ArtMethod* catch_method, uint32_t catch_dex_pc, 624 mirror::Throwable* exception_object) 625 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 626 UNUSED(thread, throw_location, catch_method, catch_dex_pc, exception_object); 627 LOG(ERROR) << "Unexpected exception caught event in tracing"; 628} 629 630void Trace::ReadClocks(Thread* thread, uint32_t* thread_clock_diff, uint32_t* wall_clock_diff) { 631 if (UseThreadCpuClock()) { 632 uint64_t clock_base = thread->GetTraceClockBase(); 633 if (UNLIKELY(clock_base == 0)) { 634 // First event, record the base time in the map. 635 uint64_t time = thread->GetCpuMicroTime(); 636 thread->SetTraceClockBase(time); 637 } else { 638 *thread_clock_diff = thread->GetCpuMicroTime() - clock_base; 639 } 640 } 641 if (UseWallClock()) { 642 *wall_clock_diff = MicroTime() - start_time_; 643 } 644} 645 646void Trace::LogMethodTraceEvent(Thread* thread, mirror::ArtMethod* method, 647 instrumentation::Instrumentation::InstrumentationEvent event, 648 uint32_t thread_clock_diff, uint32_t wall_clock_diff) { 649 // Advance cur_offset_ atomically. 650 int32_t new_offset; 651 int32_t old_offset; 652 do { 653 old_offset = cur_offset_.LoadRelaxed(); 654 new_offset = old_offset + GetRecordSize(clock_source_); 655 if (new_offset > buffer_size_) { 656 overflow_ = true; 657 return; 658 } 659 } while (!cur_offset_.CompareExchangeWeakSequentiallyConsistent(old_offset, new_offset)); 660 661 TraceAction action = kTraceMethodEnter; 662 switch (event) { 663 case instrumentation::Instrumentation::kMethodEntered: 664 action = kTraceMethodEnter; 665 break; 666 case instrumentation::Instrumentation::kMethodExited: 667 action = kTraceMethodExit; 668 break; 669 case instrumentation::Instrumentation::kMethodUnwind: 670 action = kTraceUnroll; 671 break; 672 default: 673 UNIMPLEMENTED(FATAL) << "Unexpected event: " << event; 674 } 675 676 uint32_t method_value = EncodeTraceMethodAndAction(method, action); 677 678 // Write data 679 uint8_t* ptr = buf_.get() + old_offset; 680 Append2LE(ptr, thread->GetTid()); 681 Append4LE(ptr + 2, method_value); 682 ptr += 6; 683 684 if (UseThreadCpuClock()) { 685 Append4LE(ptr, thread_clock_diff); 686 ptr += 4; 687 } 688 if (UseWallClock()) { 689 Append4LE(ptr, wall_clock_diff); 690 } 691} 692 693void Trace::GetVisitedMethods(size_t buf_size, 694 std::set<mirror::ArtMethod*>* visited_methods) { 695 uint8_t* ptr = buf_.get() + kTraceHeaderLength; 696 uint8_t* end = buf_.get() + buf_size; 697 698 while (ptr < end) { 699 uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); 700 mirror::ArtMethod* method = DecodeTraceMethodId(tmid); 701 visited_methods->insert(method); 702 ptr += GetRecordSize(clock_source_); 703 } 704} 705 706void Trace::DumpMethodList(std::ostream& os, const std::set<mirror::ArtMethod*>& visited_methods) { 707 for (const auto& method : visited_methods) { 708 os << StringPrintf("%p\t%s\t%s\t%s\t%s\n", method, 709 PrettyDescriptor(method->GetDeclaringClassDescriptor()).c_str(), method->GetName(), 710 method->GetSignature().ToString().c_str(), method->GetDeclaringClassSourceFile()); 711 } 712} 713 714static void DumpThread(Thread* t, void* arg) { 715 std::ostream& os = *reinterpret_cast<std::ostream*>(arg); 716 std::string name; 717 t->GetThreadName(name); 718 os << t->GetTid() << "\t" << name << "\n"; 719} 720 721void Trace::DumpThreadList(std::ostream& os) { 722 Thread* self = Thread::Current(); 723 for (auto it : exited_threads_) { 724 os << it.first << "\t" << it.second << "\n"; 725 } 726 Locks::thread_list_lock_->AssertNotHeld(self); 727 MutexLock mu(self, *Locks::thread_list_lock_); 728 Runtime::Current()->GetThreadList()->ForEach(DumpThread, &os); 729} 730 731void Trace::StoreExitingThreadInfo(Thread* thread) { 732 MutexLock mu(thread, *Locks::trace_lock_); 733 if (the_trace_ != nullptr) { 734 std::string name; 735 thread->GetThreadName(name); 736 // The same thread/tid may be used multiple times. As SafeMap::Put does not allow to override 737 // a previous mapping, use SafeMap::Overwrite. 738 the_trace_->exited_threads_.Overwrite(thread->GetTid(), name); 739 } 740} 741 742} // namespace art 743