1 // Copyright 2013 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #include "sampler.h" 29 30 #if V8_OS_POSIX && !V8_OS_CYGWIN 31 32 #define USE_SIGNALS 33 34 #include <errno.h> 35 #include <pthread.h> 36 #include <signal.h> 37 #include <sys/time.h> 38 #include <sys/syscall.h> 39 40 #if V8_OS_MACOSX 41 #include <mach/mach.h> 42 // OpenBSD doesn't have <ucontext.h>. ucontext_t lives in <signal.h> 43 // and is a typedef for struct sigcontext. There is no uc_mcontext. 44 #elif(!V8_OS_ANDROID || defined(__BIONIC_HAVE_UCONTEXT_T)) \ 45 && !V8_OS_OPENBSD 46 #include <ucontext.h> 47 #endif 48 #include <unistd.h> 49 50 // GLibc on ARM defines mcontext_t has a typedef for 'struct sigcontext'. 51 // Old versions of the C library <signal.h> didn't define the type. 52 #if V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) && \ 53 defined(__arm__) && !defined(__BIONIC_HAVE_STRUCT_SIGCONTEXT) 54 #include <asm/sigcontext.h> 55 #endif 56 57 #elif V8_OS_WIN || V8_OS_CYGWIN 58 59 #include "win32-headers.h" 60 61 #endif 62 63 #include "v8.h" 64 65 #include "cpu-profiler-inl.h" 66 #include "flags.h" 67 #include "frames-inl.h" 68 #include "log.h" 69 #include "platform.h" 70 #include "simulator.h" 71 #include "v8threads.h" 72 #include "vm-state-inl.h" 73 74 75 #if V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) 76 77 // Not all versions of Android's C library provide ucontext_t. 78 // Detect this and provide custom but compatible definitions. Note that these 79 // follow the GLibc naming convention to access register values from 80 // mcontext_t. 81 // 82 // See http://code.google.com/p/android/issues/detail?id=34784 83 84 #if defined(__arm__) 85 86 typedef struct sigcontext mcontext_t; 87 88 typedef struct ucontext { 89 uint32_t uc_flags; 90 struct ucontext* uc_link; 91 stack_t uc_stack; 92 mcontext_t uc_mcontext; 93 // Other fields are not used by V8, don't define them here. 94 } ucontext_t; 95 96 #elif defined(__mips__) 97 // MIPS version of sigcontext, for Android bionic. 98 typedef struct { 99 uint32_t regmask; 100 uint32_t status; 101 uint64_t pc; 102 uint64_t gregs[32]; 103 uint64_t fpregs[32]; 104 uint32_t acx; 105 uint32_t fpc_csr; 106 uint32_t fpc_eir; 107 uint32_t used_math; 108 uint32_t dsp; 109 uint64_t mdhi; 110 uint64_t mdlo; 111 uint32_t hi1; 112 uint32_t lo1; 113 uint32_t hi2; 114 uint32_t lo2; 115 uint32_t hi3; 116 uint32_t lo3; 117 } mcontext_t; 118 119 typedef struct ucontext { 120 uint32_t uc_flags; 121 struct ucontext* uc_link; 122 stack_t uc_stack; 123 mcontext_t uc_mcontext; 124 // Other fields are not used by V8, don't define them here. 125 } ucontext_t; 126 127 #elif defined(__i386__) 128 // x86 version for Android. 129 typedef struct { 130 uint32_t gregs[19]; 131 void* fpregs; 132 uint32_t oldmask; 133 uint32_t cr2; 134 } mcontext_t; 135 136 typedef uint32_t kernel_sigset_t[2]; // x86 kernel uses 64-bit signal masks 137 typedef struct ucontext { 138 uint32_t uc_flags; 139 struct ucontext* uc_link; 140 stack_t uc_stack; 141 mcontext_t uc_mcontext; 142 // Other fields are not used by V8, don't define them here. 143 } ucontext_t; 144 enum { REG_EBP = 6, REG_ESP = 7, REG_EIP = 14 }; 145 #endif 146 147 #endif // V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) 148 149 150 namespace v8 { 151 namespace internal { 152 153 namespace { 154 155 class PlatformDataCommon : public Malloced { 156 public: 157 PlatformDataCommon() : profiled_thread_id_(ThreadId::Current()) {} 158 ThreadId profiled_thread_id() { return profiled_thread_id_; } 159 160 protected: 161 ~PlatformDataCommon() {} 162 163 private: 164 ThreadId profiled_thread_id_; 165 }; 166 167 } // namespace 168 169 #if defined(USE_SIGNALS) 170 171 class Sampler::PlatformData : public PlatformDataCommon { 172 public: 173 PlatformData() : vm_tid_(pthread_self()) {} 174 pthread_t vm_tid() const { return vm_tid_; } 175 176 private: 177 pthread_t vm_tid_; 178 }; 179 180 #elif V8_OS_WIN || V8_OS_CYGWIN 181 182 // ---------------------------------------------------------------------------- 183 // Win32 profiler support. On Cygwin we use the same sampler implementation as 184 // on Win32. 185 186 class Sampler::PlatformData : public PlatformDataCommon { 187 public: 188 // Get a handle to the calling thread. This is the thread that we are 189 // going to profile. We need to make a copy of the handle because we are 190 // going to use it in the sampler thread. Using GetThreadHandle() will 191 // not work in this case. We're using OpenThread because DuplicateHandle 192 // for some reason doesn't work in Chrome's sandbox. 193 PlatformData() 194 : profiled_thread_(OpenThread(THREAD_GET_CONTEXT | 195 THREAD_SUSPEND_RESUME | 196 THREAD_QUERY_INFORMATION, 197 false, 198 GetCurrentThreadId())) {} 199 200 ~PlatformData() { 201 if (profiled_thread_ != NULL) { 202 CloseHandle(profiled_thread_); 203 profiled_thread_ = NULL; 204 } 205 } 206 207 HANDLE profiled_thread() { return profiled_thread_; } 208 209 private: 210 HANDLE profiled_thread_; 211 }; 212 #endif 213 214 215 #if defined(USE_SIMULATOR) 216 class SimulatorHelper { 217 public: 218 inline bool Init(Sampler* sampler, Isolate* isolate) { 219 simulator_ = isolate->thread_local_top()->simulator_; 220 // Check if there is active simulator. 221 return simulator_ != NULL; 222 } 223 224 inline void FillRegisters(RegisterState* state) { 225 state->pc = reinterpret_cast<Address>(simulator_->get_pc()); 226 state->sp = reinterpret_cast<Address>(simulator_->get_register( 227 Simulator::sp)); 228 #if V8_TARGET_ARCH_ARM 229 state->fp = reinterpret_cast<Address>(simulator_->get_register( 230 Simulator::r11)); 231 #elif V8_TARGET_ARCH_MIPS 232 state->fp = reinterpret_cast<Address>(simulator_->get_register( 233 Simulator::fp)); 234 #endif 235 } 236 237 private: 238 Simulator* simulator_; 239 }; 240 #endif // USE_SIMULATOR 241 242 243 #if defined(USE_SIGNALS) 244 245 class SignalHandler : public AllStatic { 246 public: 247 static void SetUp() { if (!mutex_) mutex_ = new Mutex(); } 248 static void TearDown() { delete mutex_; } 249 250 static void IncreaseSamplerCount() { 251 LockGuard<Mutex> lock_guard(mutex_); 252 if (++client_count_ == 1) Install(); 253 } 254 255 static void DecreaseSamplerCount() { 256 LockGuard<Mutex> lock_guard(mutex_); 257 if (--client_count_ == 0) Restore(); 258 } 259 260 static bool Installed() { 261 return signal_handler_installed_; 262 } 263 264 private: 265 static void Install() { 266 struct sigaction sa; 267 sa.sa_sigaction = &HandleProfilerSignal; 268 sigemptyset(&sa.sa_mask); 269 sa.sa_flags = SA_RESTART | SA_SIGINFO; 270 signal_handler_installed_ = 271 (sigaction(SIGPROF, &sa, &old_signal_handler_) == 0); 272 } 273 274 static void Restore() { 275 if (signal_handler_installed_) { 276 sigaction(SIGPROF, &old_signal_handler_, 0); 277 signal_handler_installed_ = false; 278 } 279 } 280 281 static void HandleProfilerSignal(int signal, siginfo_t* info, void* context); 282 // Protects the process wide state below. 283 static Mutex* mutex_; 284 static int client_count_; 285 static bool signal_handler_installed_; 286 static struct sigaction old_signal_handler_; 287 }; 288 289 290 Mutex* SignalHandler::mutex_ = NULL; 291 int SignalHandler::client_count_ = 0; 292 struct sigaction SignalHandler::old_signal_handler_; 293 bool SignalHandler::signal_handler_installed_ = false; 294 295 296 void SignalHandler::HandleProfilerSignal(int signal, siginfo_t* info, 297 void* context) { 298 #if V8_OS_NACL 299 // As Native Client does not support signal handling, profiling 300 // is disabled. 301 return; 302 #else 303 USE(info); 304 if (signal != SIGPROF) return; 305 Isolate* isolate = Isolate::UncheckedCurrent(); 306 if (isolate == NULL || !isolate->IsInitialized() || !isolate->IsInUse()) { 307 // We require a fully initialized and entered isolate. 308 return; 309 } 310 if (v8::Locker::IsActive() && 311 !isolate->thread_manager()->IsLockedByCurrentThread()) { 312 return; 313 } 314 315 Sampler* sampler = isolate->logger()->sampler(); 316 if (sampler == NULL) return; 317 318 RegisterState state; 319 320 #if defined(USE_SIMULATOR) 321 SimulatorHelper helper; 322 if (!helper.Init(sampler, isolate)) return; 323 helper.FillRegisters(&state); 324 #else 325 // Extracting the sample from the context is extremely machine dependent. 326 ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context); 327 #if !V8_OS_OPENBSD 328 mcontext_t& mcontext = ucontext->uc_mcontext; 329 #endif 330 #if V8_OS_LINUX 331 #if V8_HOST_ARCH_IA32 332 state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]); 333 state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]); 334 state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]); 335 #elif V8_HOST_ARCH_X64 336 state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_RIP]); 337 state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_RSP]); 338 state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_RBP]); 339 #elif V8_HOST_ARCH_ARM 340 #if defined(__GLIBC__) && !defined(__UCLIBC__) && \ 341 (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3)) 342 // Old GLibc ARM versions used a gregs[] array to access the register 343 // values from mcontext_t. 344 state.pc = reinterpret_cast<Address>(mcontext.gregs[R15]); 345 state.sp = reinterpret_cast<Address>(mcontext.gregs[R13]); 346 state.fp = reinterpret_cast<Address>(mcontext.gregs[R11]); 347 #else 348 state.pc = reinterpret_cast<Address>(mcontext.arm_pc); 349 state.sp = reinterpret_cast<Address>(mcontext.arm_sp); 350 state.fp = reinterpret_cast<Address>(mcontext.arm_fp); 351 #endif // defined(__GLIBC__) && !defined(__UCLIBC__) && 352 // (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3)) 353 #elif V8_HOST_ARCH_MIPS 354 state.pc = reinterpret_cast<Address>(mcontext.pc); 355 state.sp = reinterpret_cast<Address>(mcontext.gregs[29]); 356 state.fp = reinterpret_cast<Address>(mcontext.gregs[30]); 357 #endif // V8_HOST_ARCH_* 358 #elif V8_OS_MACOSX 359 #if V8_HOST_ARCH_X64 360 #if __DARWIN_UNIX03 361 state.pc = reinterpret_cast<Address>(mcontext->__ss.__rip); 362 state.sp = reinterpret_cast<Address>(mcontext->__ss.__rsp); 363 state.fp = reinterpret_cast<Address>(mcontext->__ss.__rbp); 364 #else // !__DARWIN_UNIX03 365 state.pc = reinterpret_cast<Address>(mcontext->ss.rip); 366 state.sp = reinterpret_cast<Address>(mcontext->ss.rsp); 367 state.fp = reinterpret_cast<Address>(mcontext->ss.rbp); 368 #endif // __DARWIN_UNIX03 369 #elif V8_HOST_ARCH_IA32 370 #if __DARWIN_UNIX03 371 state.pc = reinterpret_cast<Address>(mcontext->__ss.__eip); 372 state.sp = reinterpret_cast<Address>(mcontext->__ss.__esp); 373 state.fp = reinterpret_cast<Address>(mcontext->__ss.__ebp); 374 #else // !__DARWIN_UNIX03 375 state.pc = reinterpret_cast<Address>(mcontext->ss.eip); 376 state.sp = reinterpret_cast<Address>(mcontext->ss.esp); 377 state.fp = reinterpret_cast<Address>(mcontext->ss.ebp); 378 #endif // __DARWIN_UNIX03 379 #endif // V8_HOST_ARCH_IA32 380 #elif V8_OS_FREEBSD 381 #if V8_HOST_ARCH_IA32 382 state.pc = reinterpret_cast<Address>(mcontext.mc_eip); 383 state.sp = reinterpret_cast<Address>(mcontext.mc_esp); 384 state.fp = reinterpret_cast<Address>(mcontext.mc_ebp); 385 #elif V8_HOST_ARCH_X64 386 state.pc = reinterpret_cast<Address>(mcontext.mc_rip); 387 state.sp = reinterpret_cast<Address>(mcontext.mc_rsp); 388 state.fp = reinterpret_cast<Address>(mcontext.mc_rbp); 389 #elif V8_HOST_ARCH_ARM 390 state.pc = reinterpret_cast<Address>(mcontext.mc_r15); 391 state.sp = reinterpret_cast<Address>(mcontext.mc_r13); 392 state.fp = reinterpret_cast<Address>(mcontext.mc_r11); 393 #endif // V8_HOST_ARCH_* 394 #elif V8_OS_NETBSD 395 #if V8_HOST_ARCH_IA32 396 state.pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_EIP]); 397 state.sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_ESP]); 398 state.fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_EBP]); 399 #elif V8_HOST_ARCH_X64 400 state.pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_RIP]); 401 state.sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RSP]); 402 state.fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RBP]); 403 #endif // V8_HOST_ARCH_* 404 #elif V8_OS_OPENBSD 405 #if V8_HOST_ARCH_IA32 406 state.pc = reinterpret_cast<Address>(ucontext->sc_eip); 407 state.sp = reinterpret_cast<Address>(ucontext->sc_esp); 408 state.fp = reinterpret_cast<Address>(ucontext->sc_ebp); 409 #elif V8_HOST_ARCH_X64 410 state.pc = reinterpret_cast<Address>(ucontext->sc_rip); 411 state.sp = reinterpret_cast<Address>(ucontext->sc_rsp); 412 state.fp = reinterpret_cast<Address>(ucontext->sc_rbp); 413 #endif // V8_HOST_ARCH_* 414 #elif V8_OS_SOLARIS 415 state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_PC]); 416 state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_SP]); 417 state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_FP]); 418 #endif // V8_OS_SOLARIS 419 #endif // USE_SIMULATOR 420 sampler->SampleStack(state); 421 #endif // V8_OS_NACL 422 } 423 424 #endif 425 426 427 class SamplerThread : public Thread { 428 public: 429 static const int kSamplerThreadStackSize = 64 * KB; 430 431 explicit SamplerThread(int interval) 432 : Thread(Thread::Options("SamplerThread", kSamplerThreadStackSize)), 433 interval_(interval) {} 434 435 static void SetUp() { if (!mutex_) mutex_ = new Mutex(); } 436 static void TearDown() { delete mutex_; mutex_ = NULL; } 437 438 static void AddActiveSampler(Sampler* sampler) { 439 bool need_to_start = false; 440 LockGuard<Mutex> lock_guard(mutex_); 441 if (instance_ == NULL) { 442 // Start a thread that will send SIGPROF signal to VM threads, 443 // when CPU profiling will be enabled. 444 instance_ = new SamplerThread(sampler->interval()); 445 need_to_start = true; 446 } 447 448 ASSERT(sampler->IsActive()); 449 ASSERT(!instance_->active_samplers_.Contains(sampler)); 450 ASSERT(instance_->interval_ == sampler->interval()); 451 instance_->active_samplers_.Add(sampler); 452 453 if (need_to_start) instance_->StartSynchronously(); 454 } 455 456 static void RemoveActiveSampler(Sampler* sampler) { 457 SamplerThread* instance_to_remove = NULL; 458 { 459 LockGuard<Mutex> lock_guard(mutex_); 460 461 ASSERT(sampler->IsActive()); 462 bool removed = instance_->active_samplers_.RemoveElement(sampler); 463 ASSERT(removed); 464 USE(removed); 465 466 // We cannot delete the instance immediately as we need to Join() the 467 // thread but we are holding mutex_ and the thread may try to acquire it. 468 if (instance_->active_samplers_.is_empty()) { 469 instance_to_remove = instance_; 470 instance_ = NULL; 471 } 472 } 473 474 if (!instance_to_remove) return; 475 instance_to_remove->Join(); 476 delete instance_to_remove; 477 } 478 479 // Implement Thread::Run(). 480 virtual void Run() { 481 while (true) { 482 { 483 LockGuard<Mutex> lock_guard(mutex_); 484 if (active_samplers_.is_empty()) break; 485 // When CPU profiling is enabled both JavaScript and C++ code is 486 // profiled. We must not suspend. 487 for (int i = 0; i < active_samplers_.length(); ++i) { 488 Sampler* sampler = active_samplers_.at(i); 489 if (!sampler->isolate()->IsInitialized()) continue; 490 if (!sampler->IsProfiling()) continue; 491 sampler->DoSample(); 492 } 493 } 494 OS::Sleep(interval_); 495 } 496 } 497 498 private: 499 // Protects the process wide state below. 500 static Mutex* mutex_; 501 static SamplerThread* instance_; 502 503 const int interval_; 504 List<Sampler*> active_samplers_; 505 506 DISALLOW_COPY_AND_ASSIGN(SamplerThread); 507 }; 508 509 510 Mutex* SamplerThread::mutex_ = NULL; 511 SamplerThread* SamplerThread::instance_ = NULL; 512 513 514 // 515 // StackTracer implementation 516 // 517 DISABLE_ASAN void TickSample::Init(Isolate* isolate, 518 const RegisterState& regs) { 519 ASSERT(isolate->IsInitialized()); 520 pc = regs.pc; 521 state = isolate->current_vm_state(); 522 523 // Avoid collecting traces while doing GC. 524 if (state == GC) return; 525 526 Address js_entry_sp = isolate->js_entry_sp(); 527 if (js_entry_sp == 0) { 528 // Not executing JS now. 529 return; 530 } 531 532 ExternalCallbackScope* scope = isolate->external_callback_scope(); 533 Address handler = Isolate::handler(isolate->thread_local_top()); 534 // If there is a handler on top of the external callback scope then 535 // we have already entrered JavaScript again and the external callback 536 // is not the top function. 537 if (scope && scope->scope_address() < handler) { 538 external_callback = scope->callback(); 539 has_external_callback = true; 540 } else { 541 // Sample potential return address value for frameless invocation of 542 // stubs (we'll figure out later, if this value makes sense). 543 tos = Memory::Address_at(regs.sp); 544 has_external_callback = false; 545 } 546 547 SafeStackFrameIterator it(isolate, regs.fp, regs.sp, js_entry_sp); 548 top_frame_type = it.top_frame_type(); 549 int i = 0; 550 while (!it.done() && i < TickSample::kMaxFramesCount) { 551 stack[i++] = it.frame()->pc(); 552 it.Advance(); 553 } 554 frames_count = i; 555 } 556 557 558 void Sampler::SetUp() { 559 #if defined(USE_SIGNALS) 560 SignalHandler::SetUp(); 561 #endif 562 SamplerThread::SetUp(); 563 } 564 565 566 void Sampler::TearDown() { 567 SamplerThread::TearDown(); 568 #if defined(USE_SIGNALS) 569 SignalHandler::TearDown(); 570 #endif 571 } 572 573 574 Sampler::Sampler(Isolate* isolate, int interval) 575 : isolate_(isolate), 576 interval_(interval), 577 profiling_(false), 578 has_processing_thread_(false), 579 active_(false), 580 is_counting_samples_(false), 581 js_and_external_sample_count_(0) { 582 data_ = new PlatformData; 583 } 584 585 586 Sampler::~Sampler() { 587 ASSERT(!IsActive()); 588 delete data_; 589 } 590 591 592 void Sampler::Start() { 593 ASSERT(!IsActive()); 594 SetActive(true); 595 SamplerThread::AddActiveSampler(this); 596 } 597 598 599 void Sampler::Stop() { 600 ASSERT(IsActive()); 601 SamplerThread::RemoveActiveSampler(this); 602 SetActive(false); 603 } 604 605 606 void Sampler::IncreaseProfilingDepth() { 607 NoBarrier_AtomicIncrement(&profiling_, 1); 608 #if defined(USE_SIGNALS) 609 SignalHandler::IncreaseSamplerCount(); 610 #endif 611 } 612 613 614 void Sampler::DecreaseProfilingDepth() { 615 #if defined(USE_SIGNALS) 616 SignalHandler::DecreaseSamplerCount(); 617 #endif 618 NoBarrier_AtomicIncrement(&profiling_, -1); 619 } 620 621 622 void Sampler::SampleStack(const RegisterState& state) { 623 TickSample* sample = isolate_->cpu_profiler()->StartTickSample(); 624 TickSample sample_obj; 625 if (sample == NULL) sample = &sample_obj; 626 sample->Init(isolate_, state); 627 if (is_counting_samples_) { 628 if (sample->state == JS || sample->state == EXTERNAL) { 629 ++js_and_external_sample_count_; 630 } 631 } 632 Tick(sample); 633 if (sample != &sample_obj) { 634 isolate_->cpu_profiler()->FinishTickSample(); 635 } 636 } 637 638 639 #if defined(USE_SIGNALS) 640 641 void Sampler::DoSample() { 642 if (!SignalHandler::Installed()) return; 643 pthread_kill(platform_data()->vm_tid(), SIGPROF); 644 } 645 646 #elif V8_OS_WIN || V8_OS_CYGWIN 647 648 void Sampler::DoSample() { 649 HANDLE profiled_thread = platform_data()->profiled_thread(); 650 if (profiled_thread == NULL) return; 651 652 #if defined(USE_SIMULATOR) 653 SimulatorHelper helper; 654 if (!helper.Init(this, isolate())) return; 655 #endif 656 657 const DWORD kSuspendFailed = static_cast<DWORD>(-1); 658 if (SuspendThread(profiled_thread) == kSuspendFailed) return; 659 660 // Context used for sampling the register state of the profiled thread. 661 CONTEXT context; 662 memset(&context, 0, sizeof(context)); 663 context.ContextFlags = CONTEXT_FULL; 664 if (GetThreadContext(profiled_thread, &context) != 0) { 665 RegisterState state; 666 #if defined(USE_SIMULATOR) 667 helper.FillRegisters(&state); 668 #else 669 #if V8_HOST_ARCH_X64 670 state.pc = reinterpret_cast<Address>(context.Rip); 671 state.sp = reinterpret_cast<Address>(context.Rsp); 672 state.fp = reinterpret_cast<Address>(context.Rbp); 673 #else 674 state.pc = reinterpret_cast<Address>(context.Eip); 675 state.sp = reinterpret_cast<Address>(context.Esp); 676 state.fp = reinterpret_cast<Address>(context.Ebp); 677 #endif 678 #endif // USE_SIMULATOR 679 SampleStack(state); 680 } 681 ResumeThread(profiled_thread); 682 } 683 684 #endif // USE_SIGNALS 685 686 687 } } // namespace v8::internal 688
