Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2013 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/profiler/sampler.h" |
| 6 | |
| 7 | #if V8_OS_POSIX && !V8_OS_CYGWIN |
| 8 | |
| 9 | #define USE_SIGNALS |
| 10 | |
| 11 | #include <errno.h> |
| 12 | #include <pthread.h> |
| 13 | #include <signal.h> |
| 14 | #include <sys/time.h> |
| 15 | |
| 16 | #if !V8_OS_QNX && !V8_OS_NACL && !V8_OS_AIX |
| 17 | #include <sys/syscall.h> // NOLINT |
| 18 | #endif |
| 19 | |
| 20 | #if V8_OS_MACOSX |
| 21 | #include <mach/mach.h> |
| 22 | // OpenBSD doesn't have <ucontext.h>. ucontext_t lives in <signal.h> |
| 23 | // and is a typedef for struct sigcontext. There is no uc_mcontext. |
| 24 | #elif(!V8_OS_ANDROID || defined(__BIONIC_HAVE_UCONTEXT_T)) && \ |
| 25 | !V8_OS_OPENBSD && !V8_OS_NACL |
| 26 | #include <ucontext.h> |
| 27 | #endif |
| 28 | |
| 29 | #include <unistd.h> |
| 30 | |
| 31 | // GLibc on ARM defines mcontext_t has a typedef for 'struct sigcontext'. |
| 32 | // Old versions of the C library <signal.h> didn't define the type. |
| 33 | #if V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) && \ |
| 34 | (defined(__arm__) || defined(__aarch64__)) && \ |
| 35 | !defined(__BIONIC_HAVE_STRUCT_SIGCONTEXT) |
| 36 | #include <asm/sigcontext.h> // NOLINT |
| 37 | #endif |
| 38 | |
| 39 | #elif V8_OS_WIN || V8_OS_CYGWIN |
| 40 | |
| 41 | #include "src/base/win32-headers.h" |
| 42 | |
| 43 | #endif |
| 44 | |
| 45 | #include "src/base/platform/platform.h" |
| 46 | #include "src/flags.h" |
| 47 | #include "src/frames-inl.h" |
| 48 | #include "src/log.h" |
| 49 | #include "src/profiler/cpu-profiler-inl.h" |
| 50 | #include "src/simulator.h" |
| 51 | #include "src/v8threads.h" |
| 52 | #include "src/vm-state-inl.h" |
| 53 | |
| 54 | |
| 55 | #if V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) |
| 56 | |
| 57 | // Not all versions of Android's C library provide ucontext_t. |
| 58 | // Detect this and provide custom but compatible definitions. Note that these |
| 59 | // follow the GLibc naming convention to access register values from |
| 60 | // mcontext_t. |
| 61 | // |
| 62 | // See http://code.google.com/p/android/issues/detail?id=34784 |
| 63 | |
| 64 | #if defined(__arm__) |
| 65 | |
| 66 | typedef struct sigcontext mcontext_t; |
| 67 | |
| 68 | typedef struct ucontext { |
| 69 | uint32_t uc_flags; |
| 70 | struct ucontext* uc_link; |
| 71 | stack_t uc_stack; |
| 72 | mcontext_t uc_mcontext; |
| 73 | // Other fields are not used by V8, don't define them here. |
| 74 | } ucontext_t; |
| 75 | |
| 76 | #elif defined(__aarch64__) |
| 77 | |
| 78 | typedef struct sigcontext mcontext_t; |
| 79 | |
| 80 | typedef struct ucontext { |
| 81 | uint64_t uc_flags; |
| 82 | struct ucontext *uc_link; |
| 83 | stack_t uc_stack; |
| 84 | mcontext_t uc_mcontext; |
| 85 | // Other fields are not used by V8, don't define them here. |
| 86 | } ucontext_t; |
| 87 | |
| 88 | #elif defined(__mips__) |
| 89 | // MIPS version of sigcontext, for Android bionic. |
| 90 | typedef struct { |
| 91 | uint32_t regmask; |
| 92 | uint32_t status; |
| 93 | uint64_t pc; |
| 94 | uint64_t gregs[32]; |
| 95 | uint64_t fpregs[32]; |
| 96 | uint32_t acx; |
| 97 | uint32_t fpc_csr; |
| 98 | uint32_t fpc_eir; |
| 99 | uint32_t used_math; |
| 100 | uint32_t dsp; |
| 101 | uint64_t mdhi; |
| 102 | uint64_t mdlo; |
| 103 | uint32_t hi1; |
| 104 | uint32_t lo1; |
| 105 | uint32_t hi2; |
| 106 | uint32_t lo2; |
| 107 | uint32_t hi3; |
| 108 | uint32_t lo3; |
| 109 | } mcontext_t; |
| 110 | |
| 111 | typedef struct ucontext { |
| 112 | uint32_t uc_flags; |
| 113 | struct ucontext* uc_link; |
| 114 | stack_t uc_stack; |
| 115 | mcontext_t uc_mcontext; |
| 116 | // Other fields are not used by V8, don't define them here. |
| 117 | } ucontext_t; |
| 118 | |
| 119 | #elif defined(__i386__) |
| 120 | // x86 version for Android. |
| 121 | typedef struct { |
| 122 | uint32_t gregs[19]; |
| 123 | void* fpregs; |
| 124 | uint32_t oldmask; |
| 125 | uint32_t cr2; |
| 126 | } mcontext_t; |
| 127 | |
| 128 | typedef uint32_t kernel_sigset_t[2]; // x86 kernel uses 64-bit signal masks |
| 129 | typedef struct ucontext { |
| 130 | uint32_t uc_flags; |
| 131 | struct ucontext* uc_link; |
| 132 | stack_t uc_stack; |
| 133 | mcontext_t uc_mcontext; |
| 134 | // Other fields are not used by V8, don't define them here. |
| 135 | } ucontext_t; |
| 136 | enum { REG_EBP = 6, REG_ESP = 7, REG_EIP = 14 }; |
| 137 | |
| 138 | #elif defined(__x86_64__) |
| 139 | // x64 version for Android. |
| 140 | typedef struct { |
| 141 | uint64_t gregs[23]; |
| 142 | void* fpregs; |
| 143 | uint64_t __reserved1[8]; |
| 144 | } mcontext_t; |
| 145 | |
| 146 | typedef struct ucontext { |
| 147 | uint64_t uc_flags; |
| 148 | struct ucontext *uc_link; |
| 149 | stack_t uc_stack; |
| 150 | mcontext_t uc_mcontext; |
| 151 | // Other fields are not used by V8, don't define them here. |
| 152 | } ucontext_t; |
| 153 | enum { REG_RBP = 10, REG_RSP = 15, REG_RIP = 16 }; |
| 154 | #endif |
| 155 | |
| 156 | #endif // V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) |
| 157 | |
| 158 | |
| 159 | namespace v8 { |
| 160 | namespace internal { |
| 161 | |
| 162 | namespace { |
| 163 | |
| 164 | class PlatformDataCommon : public Malloced { |
| 165 | public: |
| 166 | PlatformDataCommon() : profiled_thread_id_(ThreadId::Current()) {} |
| 167 | ThreadId profiled_thread_id() { return profiled_thread_id_; } |
| 168 | |
| 169 | protected: |
| 170 | ~PlatformDataCommon() {} |
| 171 | |
| 172 | private: |
| 173 | ThreadId profiled_thread_id_; |
| 174 | }; |
| 175 | |
| 176 | |
| 177 | bool IsSamePage(byte* ptr1, byte* ptr2) { |
| 178 | const uint32_t kPageSize = 4096; |
| 179 | uintptr_t mask = ~static_cast<uintptr_t>(kPageSize - 1); |
| 180 | return (reinterpret_cast<uintptr_t>(ptr1) & mask) == |
| 181 | (reinterpret_cast<uintptr_t>(ptr2) & mask); |
| 182 | } |
| 183 | |
| 184 | |
| 185 | // Check if the code at specified address could potentially be a |
| 186 | // frame setup code. |
| 187 | bool IsNoFrameRegion(Address address) { |
| 188 | struct Pattern { |
| 189 | int bytes_count; |
| 190 | byte bytes[8]; |
| 191 | int offsets[4]; |
| 192 | }; |
| 193 | byte* pc = reinterpret_cast<byte*>(address); |
| 194 | static Pattern patterns[] = { |
| 195 | #if V8_HOST_ARCH_IA32 |
| 196 | // push %ebp |
| 197 | // mov %esp,%ebp |
| 198 | {3, {0x55, 0x89, 0xe5}, {0, 1, -1}}, |
| 199 | // pop %ebp |
| 200 | // ret N |
| 201 | {2, {0x5d, 0xc2}, {0, 1, -1}}, |
| 202 | // pop %ebp |
| 203 | // ret |
| 204 | {2, {0x5d, 0xc3}, {0, 1, -1}}, |
| 205 | #elif V8_HOST_ARCH_X64 |
| 206 | // pushq %rbp |
| 207 | // movq %rsp,%rbp |
| 208 | {4, {0x55, 0x48, 0x89, 0xe5}, {0, 1, -1}}, |
| 209 | // popq %rbp |
| 210 | // ret N |
| 211 | {2, {0x5d, 0xc2}, {0, 1, -1}}, |
| 212 | // popq %rbp |
| 213 | // ret |
| 214 | {2, {0x5d, 0xc3}, {0, 1, -1}}, |
| 215 | #endif |
| 216 | {0, {}, {}} |
| 217 | }; |
| 218 | for (Pattern* pattern = patterns; pattern->bytes_count; ++pattern) { |
| 219 | for (int* offset_ptr = pattern->offsets; *offset_ptr != -1; ++offset_ptr) { |
| 220 | int offset = *offset_ptr; |
| 221 | if (!offset || IsSamePage(pc, pc - offset)) { |
| 222 | MSAN_MEMORY_IS_INITIALIZED(pc - offset, pattern->bytes_count); |
| 223 | if (!memcmp(pc - offset, pattern->bytes, pattern->bytes_count)) |
| 224 | return true; |
| 225 | } else { |
| 226 | // It is not safe to examine bytes on another page as it might not be |
| 227 | // allocated thus causing a SEGFAULT. |
| 228 | // Check the pattern part that's on the same page and |
| 229 | // pessimistically assume it could be the entire pattern match. |
| 230 | MSAN_MEMORY_IS_INITIALIZED(pc, pattern->bytes_count - offset); |
| 231 | if (!memcmp(pc, pattern->bytes + offset, pattern->bytes_count - offset)) |
| 232 | return true; |
| 233 | } |
| 234 | } |
| 235 | } |
| 236 | return false; |
| 237 | } |
| 238 | |
| 239 | } // namespace |
| 240 | |
| 241 | #if defined(USE_SIGNALS) |
| 242 | |
| 243 | class Sampler::PlatformData : public PlatformDataCommon { |
| 244 | public: |
| 245 | PlatformData() : vm_tid_(pthread_self()) {} |
| 246 | pthread_t vm_tid() const { return vm_tid_; } |
| 247 | |
| 248 | private: |
| 249 | pthread_t vm_tid_; |
| 250 | }; |
| 251 | |
| 252 | #elif V8_OS_WIN || V8_OS_CYGWIN |
| 253 | |
| 254 | // ---------------------------------------------------------------------------- |
| 255 | // Win32 profiler support. On Cygwin we use the same sampler implementation as |
| 256 | // on Win32. |
| 257 | |
| 258 | class Sampler::PlatformData : public PlatformDataCommon { |
| 259 | public: |
| 260 | // Get a handle to the calling thread. This is the thread that we are |
| 261 | // going to profile. We need to make a copy of the handle because we are |
| 262 | // going to use it in the sampler thread. Using GetThreadHandle() will |
| 263 | // not work in this case. We're using OpenThread because DuplicateHandle |
| 264 | // for some reason doesn't work in Chrome's sandbox. |
| 265 | PlatformData() |
| 266 | : profiled_thread_(OpenThread(THREAD_GET_CONTEXT | |
| 267 | THREAD_SUSPEND_RESUME | |
| 268 | THREAD_QUERY_INFORMATION, |
| 269 | false, |
| 270 | GetCurrentThreadId())) {} |
| 271 | |
| 272 | ~PlatformData() { |
| 273 | if (profiled_thread_ != NULL) { |
| 274 | CloseHandle(profiled_thread_); |
| 275 | profiled_thread_ = NULL; |
| 276 | } |
| 277 | } |
| 278 | |
| 279 | HANDLE profiled_thread() { return profiled_thread_; } |
| 280 | |
| 281 | private: |
| 282 | HANDLE profiled_thread_; |
| 283 | }; |
| 284 | #endif |
| 285 | |
| 286 | |
| 287 | #if defined(USE_SIMULATOR) |
| 288 | class SimulatorHelper { |
| 289 | public: |
| 290 | inline bool Init(Isolate* isolate) { |
| 291 | simulator_ = isolate->thread_local_top()->simulator_; |
| 292 | // Check if there is active simulator. |
| 293 | return simulator_ != NULL; |
| 294 | } |
| 295 | |
| 296 | inline void FillRegisters(v8::RegisterState* state) { |
| 297 | #if V8_TARGET_ARCH_ARM |
| 298 | if (!simulator_->has_bad_pc()) { |
| 299 | state->pc = reinterpret_cast<Address>(simulator_->get_pc()); |
| 300 | } |
| 301 | state->sp = reinterpret_cast<Address>(simulator_->get_register( |
| 302 | Simulator::sp)); |
| 303 | state->fp = reinterpret_cast<Address>(simulator_->get_register( |
| 304 | Simulator::r11)); |
| 305 | #elif V8_TARGET_ARCH_ARM64 |
| 306 | if (simulator_->sp() == 0 || simulator_->fp() == 0) { |
| 307 | // It's possible that the simulator is interrupted while it is updating |
| 308 | // the sp or fp register. ARM64 simulator does this in two steps: |
| 309 | // first setting it to zero and then setting it to a new value. |
| 310 | // Bailout if sp/fp doesn't contain the new value. |
| 311 | // |
| 312 | // FIXME: The above doesn't really solve the issue. |
| 313 | // If a 64-bit target is executed on a 32-bit host even the final |
| 314 | // write is non-atomic, so it might obtain a half of the result. |
| 315 | // Moreover as long as the register set code uses memcpy (as of now), |
| 316 | // it is not guaranteed to be atomic even when both host and target |
| 317 | // are of same bitness. |
| 318 | return; |
| 319 | } |
| 320 | state->pc = reinterpret_cast<Address>(simulator_->pc()); |
| 321 | state->sp = reinterpret_cast<Address>(simulator_->sp()); |
| 322 | state->fp = reinterpret_cast<Address>(simulator_->fp()); |
| 323 | #elif V8_TARGET_ARCH_MIPS || V8_TARGET_ARCH_MIPS64 |
| 324 | if (!simulator_->has_bad_pc()) { |
| 325 | state->pc = reinterpret_cast<Address>(simulator_->get_pc()); |
| 326 | } |
| 327 | state->sp = reinterpret_cast<Address>(simulator_->get_register( |
| 328 | Simulator::sp)); |
| 329 | state->fp = reinterpret_cast<Address>(simulator_->get_register( |
| 330 | Simulator::fp)); |
| 331 | #elif V8_TARGET_ARCH_PPC |
| 332 | if (!simulator_->has_bad_pc()) { |
| 333 | state->pc = reinterpret_cast<Address>(simulator_->get_pc()); |
| 334 | } |
| 335 | state->sp = |
| 336 | reinterpret_cast<Address>(simulator_->get_register(Simulator::sp)); |
| 337 | state->fp = |
| 338 | reinterpret_cast<Address>(simulator_->get_register(Simulator::fp)); |
| 339 | #endif |
| 340 | } |
| 341 | |
| 342 | private: |
| 343 | Simulator* simulator_; |
| 344 | }; |
| 345 | #endif // USE_SIMULATOR |
| 346 | |
| 347 | |
| 348 | #if defined(USE_SIGNALS) |
| 349 | |
| 350 | class SignalHandler : public AllStatic { |
| 351 | public: |
| 352 | static void SetUp() { if (!mutex_) mutex_ = new base::Mutex(); } |
| 353 | static void TearDown() { delete mutex_; mutex_ = NULL; } |
| 354 | |
| 355 | static void IncreaseSamplerCount() { |
| 356 | base::LockGuard<base::Mutex> lock_guard(mutex_); |
| 357 | if (++client_count_ == 1) Install(); |
| 358 | } |
| 359 | |
| 360 | static void DecreaseSamplerCount() { |
| 361 | base::LockGuard<base::Mutex> lock_guard(mutex_); |
| 362 | if (--client_count_ == 0) Restore(); |
| 363 | } |
| 364 | |
| 365 | static bool Installed() { |
| 366 | return signal_handler_installed_; |
| 367 | } |
| 368 | |
| 369 | private: |
| 370 | static void Install() { |
| 371 | #if !V8_OS_NACL |
| 372 | struct sigaction sa; |
| 373 | sa.sa_sigaction = &HandleProfilerSignal; |
| 374 | sigemptyset(&sa.sa_mask); |
| 375 | #if V8_OS_QNX |
| 376 | sa.sa_flags = SA_SIGINFO; |
| 377 | #else |
| 378 | sa.sa_flags = SA_RESTART | SA_SIGINFO; |
| 379 | #endif |
| 380 | signal_handler_installed_ = |
| 381 | (sigaction(SIGPROF, &sa, &old_signal_handler_) == 0); |
| 382 | #endif |
| 383 | } |
| 384 | |
| 385 | static void Restore() { |
| 386 | #if !V8_OS_NACL |
| 387 | if (signal_handler_installed_) { |
| 388 | sigaction(SIGPROF, &old_signal_handler_, 0); |
| 389 | signal_handler_installed_ = false; |
| 390 | } |
| 391 | #endif |
| 392 | } |
| 393 | |
| 394 | #if !V8_OS_NACL |
| 395 | static void HandleProfilerSignal(int signal, siginfo_t* info, void* context); |
| 396 | #endif |
| 397 | // Protects the process wide state below. |
| 398 | static base::Mutex* mutex_; |
| 399 | static int client_count_; |
| 400 | static bool signal_handler_installed_; |
| 401 | static struct sigaction old_signal_handler_; |
| 402 | }; |
| 403 | |
| 404 | |
| 405 | base::Mutex* SignalHandler::mutex_ = NULL; |
| 406 | int SignalHandler::client_count_ = 0; |
| 407 | struct sigaction SignalHandler::old_signal_handler_; |
| 408 | bool SignalHandler::signal_handler_installed_ = false; |
| 409 | |
| 410 | |
| 411 | // As Native Client does not support signal handling, profiling is disabled. |
| 412 | #if !V8_OS_NACL |
| 413 | void SignalHandler::HandleProfilerSignal(int signal, siginfo_t* info, |
| 414 | void* context) { |
| 415 | USE(info); |
| 416 | if (signal != SIGPROF) return; |
| 417 | Isolate* isolate = Isolate::UnsafeCurrent(); |
| 418 | if (isolate == NULL || !isolate->IsInUse()) { |
| 419 | // We require a fully initialized and entered isolate. |
| 420 | return; |
| 421 | } |
| 422 | if (v8::Locker::IsActive() && |
| 423 | !isolate->thread_manager()->IsLockedByCurrentThread()) { |
| 424 | return; |
| 425 | } |
| 426 | |
| 427 | Sampler* sampler = isolate->logger()->sampler(); |
| 428 | if (sampler == NULL) return; |
| 429 | |
| 430 | v8::RegisterState state; |
| 431 | |
| 432 | #if defined(USE_SIMULATOR) |
| 433 | SimulatorHelper helper; |
| 434 | if (!helper.Init(isolate)) return; |
| 435 | helper.FillRegisters(&state); |
| 436 | // It possible that the simulator is interrupted while it is updating |
| 437 | // the sp or fp register. ARM64 simulator does this in two steps: |
| 438 | // first setting it to zero and then setting it to the new value. |
| 439 | // Bailout if sp/fp doesn't contain the new value. |
| 440 | if (state.sp == 0 || state.fp == 0) return; |
| 441 | #else |
| 442 | // Extracting the sample from the context is extremely machine dependent. |
| 443 | ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context); |
| 444 | #if !(V8_OS_OPENBSD || (V8_OS_LINUX && V8_HOST_ARCH_PPC)) |
| 445 | mcontext_t& mcontext = ucontext->uc_mcontext; |
| 446 | #endif |
| 447 | #if V8_OS_LINUX |
| 448 | #if V8_HOST_ARCH_IA32 |
| 449 | state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]); |
| 450 | state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]); |
| 451 | state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]); |
| 452 | #elif V8_HOST_ARCH_X64 |
| 453 | state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_RIP]); |
| 454 | state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_RSP]); |
| 455 | state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_RBP]); |
| 456 | #elif V8_HOST_ARCH_ARM |
| 457 | #if V8_LIBC_GLIBC && !V8_GLIBC_PREREQ(2, 4) |
| 458 | // Old GLibc ARM versions used a gregs[] array to access the register |
| 459 | // values from mcontext_t. |
| 460 | state.pc = reinterpret_cast<Address>(mcontext.gregs[R15]); |
| 461 | state.sp = reinterpret_cast<Address>(mcontext.gregs[R13]); |
| 462 | state.fp = reinterpret_cast<Address>(mcontext.gregs[R11]); |
| 463 | #else |
| 464 | state.pc = reinterpret_cast<Address>(mcontext.arm_pc); |
| 465 | state.sp = reinterpret_cast<Address>(mcontext.arm_sp); |
| 466 | state.fp = reinterpret_cast<Address>(mcontext.arm_fp); |
| 467 | #endif // V8_LIBC_GLIBC && !V8_GLIBC_PREREQ(2, 4) |
| 468 | #elif V8_HOST_ARCH_ARM64 |
| 469 | state.pc = reinterpret_cast<Address>(mcontext.pc); |
| 470 | state.sp = reinterpret_cast<Address>(mcontext.sp); |
| 471 | // FP is an alias for x29. |
| 472 | state.fp = reinterpret_cast<Address>(mcontext.regs[29]); |
| 473 | #elif V8_HOST_ARCH_MIPS |
| 474 | state.pc = reinterpret_cast<Address>(mcontext.pc); |
| 475 | state.sp = reinterpret_cast<Address>(mcontext.gregs[29]); |
| 476 | state.fp = reinterpret_cast<Address>(mcontext.gregs[30]); |
| 477 | #elif V8_HOST_ARCH_MIPS64 |
| 478 | state.pc = reinterpret_cast<Address>(mcontext.pc); |
| 479 | state.sp = reinterpret_cast<Address>(mcontext.gregs[29]); |
| 480 | state.fp = reinterpret_cast<Address>(mcontext.gregs[30]); |
| 481 | #elif V8_HOST_ARCH_PPC |
| 482 | state.pc = reinterpret_cast<Address>(ucontext->uc_mcontext.regs->nip); |
| 483 | state.sp = reinterpret_cast<Address>(ucontext->uc_mcontext.regs->gpr[PT_R1]); |
| 484 | state.fp = reinterpret_cast<Address>(ucontext->uc_mcontext.regs->gpr[PT_R31]); |
| 485 | #endif // V8_HOST_ARCH_* |
| 486 | #elif V8_OS_MACOSX |
| 487 | #if V8_HOST_ARCH_X64 |
| 488 | #if __DARWIN_UNIX03 |
| 489 | state.pc = reinterpret_cast<Address>(mcontext->__ss.__rip); |
| 490 | state.sp = reinterpret_cast<Address>(mcontext->__ss.__rsp); |
| 491 | state.fp = reinterpret_cast<Address>(mcontext->__ss.__rbp); |
| 492 | #else // !__DARWIN_UNIX03 |
| 493 | state.pc = reinterpret_cast<Address>(mcontext->ss.rip); |
| 494 | state.sp = reinterpret_cast<Address>(mcontext->ss.rsp); |
| 495 | state.fp = reinterpret_cast<Address>(mcontext->ss.rbp); |
| 496 | #endif // __DARWIN_UNIX03 |
| 497 | #elif V8_HOST_ARCH_IA32 |
| 498 | #if __DARWIN_UNIX03 |
| 499 | state.pc = reinterpret_cast<Address>(mcontext->__ss.__eip); |
| 500 | state.sp = reinterpret_cast<Address>(mcontext->__ss.__esp); |
| 501 | state.fp = reinterpret_cast<Address>(mcontext->__ss.__ebp); |
| 502 | #else // !__DARWIN_UNIX03 |
| 503 | state.pc = reinterpret_cast<Address>(mcontext->ss.eip); |
| 504 | state.sp = reinterpret_cast<Address>(mcontext->ss.esp); |
| 505 | state.fp = reinterpret_cast<Address>(mcontext->ss.ebp); |
| 506 | #endif // __DARWIN_UNIX03 |
| 507 | #endif // V8_HOST_ARCH_IA32 |
| 508 | #elif V8_OS_FREEBSD |
| 509 | #if V8_HOST_ARCH_IA32 |
| 510 | state.pc = reinterpret_cast<Address>(mcontext.mc_eip); |
| 511 | state.sp = reinterpret_cast<Address>(mcontext.mc_esp); |
| 512 | state.fp = reinterpret_cast<Address>(mcontext.mc_ebp); |
| 513 | #elif V8_HOST_ARCH_X64 |
| 514 | state.pc = reinterpret_cast<Address>(mcontext.mc_rip); |
| 515 | state.sp = reinterpret_cast<Address>(mcontext.mc_rsp); |
| 516 | state.fp = reinterpret_cast<Address>(mcontext.mc_rbp); |
| 517 | #elif V8_HOST_ARCH_ARM |
| 518 | state.pc = reinterpret_cast<Address>(mcontext.mc_r15); |
| 519 | state.sp = reinterpret_cast<Address>(mcontext.mc_r13); |
| 520 | state.fp = reinterpret_cast<Address>(mcontext.mc_r11); |
| 521 | #endif // V8_HOST_ARCH_* |
| 522 | #elif V8_OS_NETBSD |
| 523 | #if V8_HOST_ARCH_IA32 |
| 524 | state.pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_EIP]); |
| 525 | state.sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_ESP]); |
| 526 | state.fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_EBP]); |
| 527 | #elif V8_HOST_ARCH_X64 |
| 528 | state.pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_RIP]); |
| 529 | state.sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RSP]); |
| 530 | state.fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RBP]); |
| 531 | #endif // V8_HOST_ARCH_* |
| 532 | #elif V8_OS_OPENBSD |
| 533 | #if V8_HOST_ARCH_IA32 |
| 534 | state.pc = reinterpret_cast<Address>(ucontext->sc_eip); |
| 535 | state.sp = reinterpret_cast<Address>(ucontext->sc_esp); |
| 536 | state.fp = reinterpret_cast<Address>(ucontext->sc_ebp); |
| 537 | #elif V8_HOST_ARCH_X64 |
| 538 | state.pc = reinterpret_cast<Address>(ucontext->sc_rip); |
| 539 | state.sp = reinterpret_cast<Address>(ucontext->sc_rsp); |
| 540 | state.fp = reinterpret_cast<Address>(ucontext->sc_rbp); |
| 541 | #endif // V8_HOST_ARCH_* |
| 542 | #elif V8_OS_SOLARIS |
| 543 | state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_PC]); |
| 544 | state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_SP]); |
| 545 | state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_FP]); |
| 546 | #elif V8_OS_QNX |
| 547 | #if V8_HOST_ARCH_IA32 |
| 548 | state.pc = reinterpret_cast<Address>(mcontext.cpu.eip); |
| 549 | state.sp = reinterpret_cast<Address>(mcontext.cpu.esp); |
| 550 | state.fp = reinterpret_cast<Address>(mcontext.cpu.ebp); |
| 551 | #elif V8_HOST_ARCH_ARM |
| 552 | state.pc = reinterpret_cast<Address>(mcontext.cpu.gpr[ARM_REG_PC]); |
| 553 | state.sp = reinterpret_cast<Address>(mcontext.cpu.gpr[ARM_REG_SP]); |
| 554 | state.fp = reinterpret_cast<Address>(mcontext.cpu.gpr[ARM_REG_FP]); |
| 555 | #endif // V8_HOST_ARCH_* |
| 556 | #elif V8_OS_AIX |
| 557 | state.pc = reinterpret_cast<Address>(mcontext.jmp_context.iar); |
| 558 | state.sp = reinterpret_cast<Address>(mcontext.jmp_context.gpr[1]); |
| 559 | state.fp = reinterpret_cast<Address>(mcontext.jmp_context.gpr[31]); |
| 560 | #endif // V8_OS_AIX |
| 561 | #endif // USE_SIMULATOR |
| 562 | sampler->SampleStack(state); |
| 563 | } |
| 564 | #endif // V8_OS_NACL |
| 565 | |
| 566 | #endif |
| 567 | |
| 568 | |
| 569 | class SamplerThread : public base::Thread { |
| 570 | public: |
| 571 | static const int kSamplerThreadStackSize = 64 * KB; |
| 572 | |
| 573 | explicit SamplerThread(int interval) |
| 574 | : Thread(base::Thread::Options("SamplerThread", kSamplerThreadStackSize)), |
| 575 | interval_(interval) {} |
| 576 | |
| 577 | static void SetUp() { if (!mutex_) mutex_ = new base::Mutex(); } |
| 578 | static void TearDown() { delete mutex_; mutex_ = NULL; } |
| 579 | |
| 580 | static void AddActiveSampler(Sampler* sampler) { |
| 581 | bool need_to_start = false; |
| 582 | base::LockGuard<base::Mutex> lock_guard(mutex_); |
| 583 | if (instance_ == NULL) { |
| 584 | // Start a thread that will send SIGPROF signal to VM threads, |
| 585 | // when CPU profiling will be enabled. |
| 586 | instance_ = new SamplerThread(sampler->interval()); |
| 587 | need_to_start = true; |
| 588 | } |
| 589 | |
| 590 | DCHECK(sampler->IsActive()); |
| 591 | DCHECK(!instance_->active_samplers_.Contains(sampler)); |
| 592 | DCHECK(instance_->interval_ == sampler->interval()); |
| 593 | instance_->active_samplers_.Add(sampler); |
| 594 | |
| 595 | if (need_to_start) instance_->StartSynchronously(); |
| 596 | } |
| 597 | |
| 598 | static void RemoveActiveSampler(Sampler* sampler) { |
| 599 | SamplerThread* instance_to_remove = NULL; |
| 600 | { |
| 601 | base::LockGuard<base::Mutex> lock_guard(mutex_); |
| 602 | |
| 603 | DCHECK(sampler->IsActive()); |
| 604 | bool removed = instance_->active_samplers_.RemoveElement(sampler); |
| 605 | DCHECK(removed); |
| 606 | USE(removed); |
| 607 | |
| 608 | // We cannot delete the instance immediately as we need to Join() the |
| 609 | // thread but we are holding mutex_ and the thread may try to acquire it. |
| 610 | if (instance_->active_samplers_.is_empty()) { |
| 611 | instance_to_remove = instance_; |
| 612 | instance_ = NULL; |
| 613 | } |
| 614 | } |
| 615 | |
| 616 | if (!instance_to_remove) return; |
| 617 | instance_to_remove->Join(); |
| 618 | delete instance_to_remove; |
| 619 | } |
| 620 | |
| 621 | // Implement Thread::Run(). |
| 622 | virtual void Run() { |
| 623 | while (true) { |
| 624 | { |
| 625 | base::LockGuard<base::Mutex> lock_guard(mutex_); |
| 626 | if (active_samplers_.is_empty()) break; |
| 627 | // When CPU profiling is enabled both JavaScript and C++ code is |
| 628 | // profiled. We must not suspend. |
| 629 | for (int i = 0; i < active_samplers_.length(); ++i) { |
| 630 | Sampler* sampler = active_samplers_.at(i); |
| 631 | if (!sampler->IsProfiling()) continue; |
| 632 | sampler->DoSample(); |
| 633 | } |
| 634 | } |
| 635 | base::OS::Sleep(base::TimeDelta::FromMilliseconds(interval_)); |
| 636 | } |
| 637 | } |
| 638 | |
| 639 | private: |
| 640 | // Protects the process wide state below. |
| 641 | static base::Mutex* mutex_; |
| 642 | static SamplerThread* instance_; |
| 643 | |
| 644 | const int interval_; |
| 645 | List<Sampler*> active_samplers_; |
| 646 | |
| 647 | DISALLOW_COPY_AND_ASSIGN(SamplerThread); |
| 648 | }; |
| 649 | |
| 650 | |
| 651 | base::Mutex* SamplerThread::mutex_ = NULL; |
| 652 | SamplerThread* SamplerThread::instance_ = NULL; |
| 653 | |
| 654 | |
| 655 | // |
| 656 | // StackTracer implementation |
| 657 | // |
| 658 | DISABLE_ASAN void TickSample::Init(Isolate* isolate, |
| 659 | const v8::RegisterState& regs, |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 660 | RecordCEntryFrame record_c_entry_frame, |
| 661 | bool update_stats) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 662 | timestamp = base::TimeTicks::HighResolutionNow(); |
| 663 | pc = reinterpret_cast<Address>(regs.pc); |
| 664 | state = isolate->current_vm_state(); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 665 | this->update_stats = update_stats; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 666 | |
| 667 | // Avoid collecting traces while doing GC. |
| 668 | if (state == GC) return; |
| 669 | |
| 670 | Address js_entry_sp = isolate->js_entry_sp(); |
| 671 | if (js_entry_sp == 0) return; // Not executing JS now. |
| 672 | |
| 673 | if (pc && IsNoFrameRegion(pc)) { |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 674 | // Can't collect stack. Mark the sample as spoiled. |
| 675 | timestamp = base::TimeTicks(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 676 | pc = 0; |
| 677 | return; |
| 678 | } |
| 679 | |
| 680 | ExternalCallbackScope* scope = isolate->external_callback_scope(); |
| 681 | Address handler = Isolate::handler(isolate->thread_local_top()); |
| 682 | // If there is a handler on top of the external callback scope then |
| 683 | // we have already entrered JavaScript again and the external callback |
| 684 | // is not the top function. |
| 685 | if (scope && scope->scope_address() < handler) { |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 686 | external_callback_entry = *scope->callback_entrypoint_address(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 687 | has_external_callback = true; |
| 688 | } else { |
| 689 | // sp register may point at an arbitrary place in memory, make |
| 690 | // sure MSAN doesn't complain about it. |
| 691 | MSAN_MEMORY_IS_INITIALIZED(regs.sp, sizeof(Address)); |
| 692 | // Sample potential return address value for frameless invocation of |
| 693 | // stubs (we'll figure out later, if this value makes sense). |
| 694 | tos = Memory::Address_at(reinterpret_cast<Address>(regs.sp)); |
| 695 | has_external_callback = false; |
| 696 | } |
| 697 | |
| 698 | SafeStackFrameIterator it(isolate, reinterpret_cast<Address>(regs.fp), |
| 699 | reinterpret_cast<Address>(regs.sp), js_entry_sp); |
| 700 | top_frame_type = it.top_frame_type(); |
| 701 | |
| 702 | SampleInfo info; |
| 703 | GetStackSample(isolate, regs, record_c_entry_frame, |
| 704 | reinterpret_cast<void**>(&stack[0]), kMaxFramesCount, &info); |
| 705 | frames_count = static_cast<unsigned>(info.frames_count); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 706 | if (!frames_count) { |
| 707 | // It is executing JS but failed to collect a stack trace. |
| 708 | // Mark the sample as spoiled. |
| 709 | timestamp = base::TimeTicks(); |
| 710 | pc = 0; |
| 711 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 712 | } |
| 713 | |
| 714 | |
| 715 | void TickSample::GetStackSample(Isolate* isolate, const v8::RegisterState& regs, |
| 716 | RecordCEntryFrame record_c_entry_frame, |
| 717 | void** frames, size_t frames_limit, |
| 718 | v8::SampleInfo* sample_info) { |
| 719 | sample_info->frames_count = 0; |
| 720 | sample_info->vm_state = isolate->current_vm_state(); |
| 721 | if (sample_info->vm_state == GC) return; |
| 722 | |
| 723 | Address js_entry_sp = isolate->js_entry_sp(); |
| 724 | if (js_entry_sp == 0) return; // Not executing JS now. |
| 725 | |
| 726 | SafeStackFrameIterator it(isolate, reinterpret_cast<Address>(regs.fp), |
| 727 | reinterpret_cast<Address>(regs.sp), js_entry_sp); |
| 728 | size_t i = 0; |
| 729 | if (record_c_entry_frame == kIncludeCEntryFrame && !it.done() && |
| 730 | it.top_frame_type() == StackFrame::EXIT) { |
| 731 | frames[i++] = isolate->c_function(); |
| 732 | } |
| 733 | while (!it.done() && i < frames_limit) { |
| 734 | frames[i++] = it.frame()->pc(); |
| 735 | it.Advance(); |
| 736 | } |
| 737 | sample_info->frames_count = i; |
| 738 | } |
| 739 | |
| 740 | |
| 741 | void Sampler::SetUp() { |
| 742 | #if defined(USE_SIGNALS) |
| 743 | SignalHandler::SetUp(); |
| 744 | #endif |
| 745 | SamplerThread::SetUp(); |
| 746 | } |
| 747 | |
| 748 | |
| 749 | void Sampler::TearDown() { |
| 750 | SamplerThread::TearDown(); |
| 751 | #if defined(USE_SIGNALS) |
| 752 | SignalHandler::TearDown(); |
| 753 | #endif |
| 754 | } |
| 755 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 756 | Sampler::Sampler(Isolate* isolate, int interval) |
| 757 | : isolate_(isolate), |
| 758 | interval_(interval), |
| 759 | profiling_(false), |
| 760 | has_processing_thread_(false), |
| 761 | active_(false), |
| 762 | is_counting_samples_(false), |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 763 | js_sample_count_(0), |
| 764 | external_sample_count_(0) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 765 | data_ = new PlatformData; |
| 766 | } |
| 767 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 768 | Sampler::~Sampler() { |
| 769 | DCHECK(!IsActive()); |
| 770 | delete data_; |
| 771 | } |
| 772 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 773 | void Sampler::Start() { |
| 774 | DCHECK(!IsActive()); |
| 775 | SetActive(true); |
| 776 | SamplerThread::AddActiveSampler(this); |
| 777 | } |
| 778 | |
| 779 | |
| 780 | void Sampler::Stop() { |
| 781 | DCHECK(IsActive()); |
| 782 | SamplerThread::RemoveActiveSampler(this); |
| 783 | SetActive(false); |
| 784 | } |
| 785 | |
| 786 | |
| 787 | void Sampler::IncreaseProfilingDepth() { |
| 788 | base::NoBarrier_AtomicIncrement(&profiling_, 1); |
| 789 | #if defined(USE_SIGNALS) |
| 790 | SignalHandler::IncreaseSamplerCount(); |
| 791 | #endif |
| 792 | } |
| 793 | |
| 794 | |
| 795 | void Sampler::DecreaseProfilingDepth() { |
| 796 | #if defined(USE_SIGNALS) |
| 797 | SignalHandler::DecreaseSamplerCount(); |
| 798 | #endif |
| 799 | base::NoBarrier_AtomicIncrement(&profiling_, -1); |
| 800 | } |
| 801 | |
| 802 | |
| 803 | void Sampler::SampleStack(const v8::RegisterState& state) { |
| 804 | TickSample* sample = isolate_->cpu_profiler()->StartTickSample(); |
| 805 | TickSample sample_obj; |
| 806 | if (sample == NULL) sample = &sample_obj; |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame^] | 807 | sample->Init(isolate_, state, TickSample::kIncludeCEntryFrame, true); |
| 808 | if (is_counting_samples_ && !sample->timestamp.IsNull()) { |
| 809 | if (sample->state == JS) ++js_sample_count_; |
| 810 | if (sample->state == EXTERNAL) ++external_sample_count_; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 811 | } |
| 812 | Tick(sample); |
| 813 | if (sample != &sample_obj) { |
| 814 | isolate_->cpu_profiler()->FinishTickSample(); |
| 815 | } |
| 816 | } |
| 817 | |
| 818 | |
| 819 | #if defined(USE_SIGNALS) |
| 820 | |
| 821 | void Sampler::DoSample() { |
| 822 | if (!SignalHandler::Installed()) return; |
| 823 | pthread_kill(platform_data()->vm_tid(), SIGPROF); |
| 824 | } |
| 825 | |
| 826 | #elif V8_OS_WIN || V8_OS_CYGWIN |
| 827 | |
| 828 | void Sampler::DoSample() { |
| 829 | HANDLE profiled_thread = platform_data()->profiled_thread(); |
| 830 | if (profiled_thread == NULL) return; |
| 831 | |
| 832 | #if defined(USE_SIMULATOR) |
| 833 | SimulatorHelper helper; |
| 834 | if (!helper.Init(isolate())) return; |
| 835 | #endif |
| 836 | |
| 837 | const DWORD kSuspendFailed = static_cast<DWORD>(-1); |
| 838 | if (SuspendThread(profiled_thread) == kSuspendFailed) return; |
| 839 | |
| 840 | // Context used for sampling the register state of the profiled thread. |
| 841 | CONTEXT context; |
| 842 | memset(&context, 0, sizeof(context)); |
| 843 | context.ContextFlags = CONTEXT_FULL; |
| 844 | if (GetThreadContext(profiled_thread, &context) != 0) { |
| 845 | v8::RegisterState state; |
| 846 | #if defined(USE_SIMULATOR) |
| 847 | helper.FillRegisters(&state); |
| 848 | #else |
| 849 | #if V8_HOST_ARCH_X64 |
| 850 | state.pc = reinterpret_cast<Address>(context.Rip); |
| 851 | state.sp = reinterpret_cast<Address>(context.Rsp); |
| 852 | state.fp = reinterpret_cast<Address>(context.Rbp); |
| 853 | #else |
| 854 | state.pc = reinterpret_cast<Address>(context.Eip); |
| 855 | state.sp = reinterpret_cast<Address>(context.Esp); |
| 856 | state.fp = reinterpret_cast<Address>(context.Ebp); |
| 857 | #endif |
| 858 | #endif // USE_SIMULATOR |
| 859 | SampleStack(state); |
| 860 | } |
| 861 | ResumeThread(profiled_thread); |
| 862 | } |
| 863 | |
| 864 | #endif // USE_SIGNALS |
| 865 | |
| 866 | |
| 867 | } // namespace internal |
| 868 | } // namespace v8 |