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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/atomic-utils.h" | |
46 #include "src/base/platform/platform.h" | |
47 #include "src/profiler/cpu-profiler-inl.h" | |
48 #include "src/profiler/tick-sample.h" | |
49 #include "src/simulator.h" | |
50 #include "src/v8threads.h" | |
51 | |
52 | |
53 #if V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) | |
54 | |
55 // Not all versions of Android's C library provide ucontext_t. | |
56 // Detect this and provide custom but compatible definitions. Note that these | |
57 // follow the GLibc naming convention to access register values from | |
58 // mcontext_t. | |
59 // | |
60 // See http://code.google.com/p/android/issues/detail?id=34784 | |
61 | |
62 #if defined(__arm__) | |
63 | |
64 typedef struct sigcontext mcontext_t; | |
65 | |
66 typedef struct ucontext { | |
67 uint32_t uc_flags; | |
68 struct ucontext* uc_link; | |
69 stack_t uc_stack; | |
70 mcontext_t uc_mcontext; | |
71 // Other fields are not used by V8, don't define them here. | |
72 } ucontext_t; | |
73 | |
74 #elif defined(__aarch64__) | |
75 | |
76 typedef struct sigcontext mcontext_t; | |
77 | |
78 typedef struct ucontext { | |
79 uint64_t uc_flags; | |
80 struct ucontext *uc_link; | |
81 stack_t uc_stack; | |
82 mcontext_t uc_mcontext; | |
83 // Other fields are not used by V8, don't define them here. | |
84 } ucontext_t; | |
85 | |
86 #elif defined(__mips__) | |
87 // MIPS version of sigcontext, for Android bionic. | |
88 typedef struct { | |
89 uint32_t regmask; | |
90 uint32_t status; | |
91 uint64_t pc; | |
92 uint64_t gregs[32]; | |
93 uint64_t fpregs[32]; | |
94 uint32_t acx; | |
95 uint32_t fpc_csr; | |
96 uint32_t fpc_eir; | |
97 uint32_t used_math; | |
98 uint32_t dsp; | |
99 uint64_t mdhi; | |
100 uint64_t mdlo; | |
101 uint32_t hi1; | |
102 uint32_t lo1; | |
103 uint32_t hi2; | |
104 uint32_t lo2; | |
105 uint32_t hi3; | |
106 uint32_t lo3; | |
107 } mcontext_t; | |
108 | |
109 typedef struct ucontext { | |
110 uint32_t uc_flags; | |
111 struct ucontext* uc_link; | |
112 stack_t uc_stack; | |
113 mcontext_t uc_mcontext; | |
114 // Other fields are not used by V8, don't define them here. | |
115 } ucontext_t; | |
116 | |
117 #elif defined(__i386__) | |
118 // x86 version for Android. | |
119 typedef struct { | |
120 uint32_t gregs[19]; | |
121 void* fpregs; | |
122 uint32_t oldmask; | |
123 uint32_t cr2; | |
124 } mcontext_t; | |
125 | |
126 typedef uint32_t kernel_sigset_t[2]; // x86 kernel uses 64-bit signal masks | |
127 typedef struct ucontext { | |
128 uint32_t uc_flags; | |
129 struct ucontext* uc_link; | |
130 stack_t uc_stack; | |
131 mcontext_t uc_mcontext; | |
132 // Other fields are not used by V8, don't define them here. | |
133 } ucontext_t; | |
134 enum { REG_EBP = 6, REG_ESP = 7, REG_EIP = 14 }; | |
135 | |
136 #elif defined(__x86_64__) | |
137 // x64 version for Android. | |
138 typedef struct { | |
139 uint64_t gregs[23]; | |
140 void* fpregs; | |
141 uint64_t __reserved1[8]; | |
142 } mcontext_t; | |
143 | |
144 typedef struct ucontext { | |
145 uint64_t uc_flags; | |
146 struct ucontext *uc_link; | |
147 stack_t uc_stack; | |
148 mcontext_t uc_mcontext; | |
149 // Other fields are not used by V8, don't define them here. | |
150 } ucontext_t; | |
151 enum { REG_RBP = 10, REG_RSP = 15, REG_RIP = 16 }; | |
152 #endif | |
153 | |
154 #endif // V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T) | |
155 | |
156 | |
157 namespace v8 { | |
158 namespace internal { | |
159 | |
160 namespace { | |
161 | |
162 class PlatformDataCommon : public Malloced { | |
163 public: | |
164 PlatformDataCommon() : profiled_thread_id_(ThreadId::Current()) {} | |
165 ThreadId profiled_thread_id() { return profiled_thread_id_; } | |
166 | |
167 protected: | |
168 ~PlatformDataCommon() {} | |
169 | |
170 private: | |
171 ThreadId profiled_thread_id_; | |
172 }; | |
173 | |
174 | |
175 typedef List<Sampler*> SamplerList; | |
176 | |
177 #if defined(USE_SIGNALS) | |
178 class AtomicGuard { | |
179 public: | |
180 explicit AtomicGuard(base::AtomicValue<int>* atomic, bool is_block = true) | |
181 : atomic_(atomic), | |
182 is_success_(false) { | |
183 do { | |
184 // Use Acquire_Load to gain mutual exclusion. | |
185 USE(atomic_->Value()); | |
186 is_success_ = atomic_->TrySetValue(0, 1); | |
187 } while (is_block && !is_success_); | |
188 } | |
189 | |
190 bool is_success() { return is_success_; } | |
191 | |
192 ~AtomicGuard() { | |
193 if (is_success_) { | |
194 atomic_->SetValue(0); | |
195 } | |
196 atomic_ = NULL; | |
197 } | |
198 | |
199 private: | |
200 base::AtomicValue<int>* atomic_; | |
201 bool is_success_; | |
202 }; | |
203 | |
204 | |
205 // Returns key for hash map. | |
206 void* ThreadKey(pthread_t thread_id) { | |
207 return reinterpret_cast<void*>(thread_id); | |
208 } | |
209 | |
210 | |
211 // Returns hash value for hash map. | |
212 uint32_t ThreadHash(pthread_t thread_id) { | |
213 #if V8_OS_MACOSX | |
214 return static_cast<uint32_t>(reinterpret_cast<intptr_t>(thread_id)); | |
215 #else | |
216 return static_cast<uint32_t>(thread_id); | |
217 #endif | |
218 } | |
219 #endif // USE_SIGNALS | |
220 | |
221 } // namespace | |
222 | |
223 #if defined(USE_SIGNALS) | |
224 | |
225 class Sampler::PlatformData : public PlatformDataCommon { | |
226 public: | |
227 PlatformData() : vm_tid_(pthread_self()) {} | |
228 pthread_t vm_tid() const { return vm_tid_; } | |
229 | |
230 private: | |
231 pthread_t vm_tid_; | |
232 }; | |
233 | |
234 #elif V8_OS_WIN || V8_OS_CYGWIN | |
235 | |
236 // ---------------------------------------------------------------------------- | |
237 // Win32 profiler support. On Cygwin we use the same sampler implementation as | |
238 // on Win32. | |
239 | |
240 class Sampler::PlatformData : public PlatformDataCommon { | |
241 public: | |
242 // Get a handle to the calling thread. This is the thread that we are | |
243 // going to profile. We need to make a copy of the handle because we are | |
244 // going to use it in the sampler thread. Using GetThreadHandle() will | |
245 // not work in this case. We're using OpenThread because DuplicateHandle | |
246 // for some reason doesn't work in Chrome's sandbox. | |
247 PlatformData() | |
248 : profiled_thread_(OpenThread(THREAD_GET_CONTEXT | | |
249 THREAD_SUSPEND_RESUME | | |
250 THREAD_QUERY_INFORMATION, | |
251 false, | |
252 GetCurrentThreadId())) {} | |
253 | |
254 ~PlatformData() { | |
255 if (profiled_thread_ != NULL) { | |
256 CloseHandle(profiled_thread_); | |
257 profiled_thread_ = NULL; | |
258 } | |
259 } | |
260 | |
261 HANDLE profiled_thread() { return profiled_thread_; } | |
262 | |
263 private: | |
264 HANDLE profiled_thread_; | |
265 }; | |
266 #endif | |
267 | |
268 | |
269 #if defined(USE_SIGNALS) | |
270 | |
271 class SignalHandler : public AllStatic { | |
272 public: | |
273 static void SetUp() { if (!mutex_) mutex_ = new base::Mutex(); } | |
274 static void TearDown() { delete mutex_; mutex_ = NULL; } | |
275 | |
276 static void IncreaseSamplerCount() { | |
277 base::LockGuard<base::Mutex> lock_guard(mutex_); | |
278 if (++client_count_ == 1) Install(); | |
279 } | |
280 | |
281 static void DecreaseSamplerCount() { | |
282 base::LockGuard<base::Mutex> lock_guard(mutex_); | |
283 if (--client_count_ == 0) Restore(); | |
284 } | |
285 | |
286 static bool Installed() { | |
287 return signal_handler_installed_; | |
288 } | |
289 | |
290 #if !V8_OS_NACL | |
291 static void CollectSample(void* context, Sampler* sampler); | |
292 #endif | |
293 | |
294 private: | |
295 static void Install() { | |
296 #if !V8_OS_NACL | |
297 struct sigaction sa; | |
298 sa.sa_sigaction = &HandleProfilerSignal; | |
299 sigemptyset(&sa.sa_mask); | |
300 #if V8_OS_QNX | |
301 sa.sa_flags = SA_SIGINFO; | |
302 #else | |
303 sa.sa_flags = SA_RESTART | SA_SIGINFO; | |
304 #endif | |
305 signal_handler_installed_ = | |
306 (sigaction(SIGPROF, &sa, &old_signal_handler_) == 0); | |
307 #endif | |
308 } | |
309 | |
310 static void Restore() { | |
311 #if !V8_OS_NACL | |
312 if (signal_handler_installed_) { | |
313 sigaction(SIGPROF, &old_signal_handler_, 0); | |
314 signal_handler_installed_ = false; | |
315 } | |
316 #endif | |
317 } | |
318 | |
319 #if !V8_OS_NACL | |
320 static void HandleProfilerSignal(int signal, siginfo_t* info, void* context); | |
321 #endif | |
322 // Protects the process wide state below. | |
323 static base::Mutex* mutex_; | |
324 static int client_count_; | |
325 static bool signal_handler_installed_; | |
326 static struct sigaction old_signal_handler_; | |
327 }; | |
328 | |
329 | |
330 base::Mutex* SignalHandler::mutex_ = NULL; | |
331 int SignalHandler::client_count_ = 0; | |
332 struct sigaction SignalHandler::old_signal_handler_; | |
333 bool SignalHandler::signal_handler_installed_ = false; | |
334 | |
335 | |
336 // As Native Client does not support signal handling, profiling is disabled. | |
337 #if !V8_OS_NACL | |
338 void SignalHandler::CollectSample(void* context, Sampler* sampler) { | |
339 if (sampler == NULL || (!sampler->IsProfiling() && | |
340 !sampler->IsRegistered())) { | |
341 return; | |
342 } | |
343 Isolate* isolate = sampler->isolate(); | |
344 | |
345 // We require a fully initialized and entered isolate. | |
346 if (isolate == NULL || !isolate->IsInUse()) return; | |
347 | |
348 if (v8::Locker::IsActive() && | |
349 !isolate->thread_manager()->IsLockedByCurrentThread()) { | |
350 return; | |
351 } | |
352 | |
353 v8::RegisterState state; | |
354 | |
355 #if defined(USE_SIMULATOR) | |
356 if (!SimulatorHelper::FillRegisters(isolate, &state)) return; | |
357 #else | |
358 // Extracting the sample from the context is extremely machine dependent. | |
359 ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context); | |
360 #if !(V8_OS_OPENBSD || (V8_OS_LINUX && (V8_HOST_ARCH_PPC || V8_HOST_ARCH_S390))) | |
361 mcontext_t& mcontext = ucontext->uc_mcontext; | |
362 #endif | |
363 #if V8_OS_LINUX | |
364 #if V8_HOST_ARCH_IA32 | |
365 state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]); | |
366 state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]); | |
367 state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]); | |
368 #elif V8_HOST_ARCH_X64 | |
369 state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_RIP]); | |
370 state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_RSP]); | |
371 state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_RBP]); | |
372 #elif V8_HOST_ARCH_ARM | |
373 #if V8_LIBC_GLIBC && !V8_GLIBC_PREREQ(2, 4) | |
374 // Old GLibc ARM versions used a gregs[] array to access the register | |
375 // values from mcontext_t. | |
376 state.pc = reinterpret_cast<Address>(mcontext.gregs[R15]); | |
377 state.sp = reinterpret_cast<Address>(mcontext.gregs[R13]); | |
378 state.fp = reinterpret_cast<Address>(mcontext.gregs[R11]); | |
379 #else | |
380 state.pc = reinterpret_cast<Address>(mcontext.arm_pc); | |
381 state.sp = reinterpret_cast<Address>(mcontext.arm_sp); | |
382 state.fp = reinterpret_cast<Address>(mcontext.arm_fp); | |
383 #endif // V8_LIBC_GLIBC && !V8_GLIBC_PREREQ(2, 4) | |
384 #elif V8_HOST_ARCH_ARM64 | |
385 state.pc = reinterpret_cast<Address>(mcontext.pc); | |
386 state.sp = reinterpret_cast<Address>(mcontext.sp); | |
387 // FP is an alias for x29. | |
388 state.fp = reinterpret_cast<Address>(mcontext.regs[29]); | |
389 #elif V8_HOST_ARCH_MIPS | |
390 state.pc = reinterpret_cast<Address>(mcontext.pc); | |
391 state.sp = reinterpret_cast<Address>(mcontext.gregs[29]); | |
392 state.fp = reinterpret_cast<Address>(mcontext.gregs[30]); | |
393 #elif V8_HOST_ARCH_MIPS64 | |
394 state.pc = reinterpret_cast<Address>(mcontext.pc); | |
395 state.sp = reinterpret_cast<Address>(mcontext.gregs[29]); | |
396 state.fp = reinterpret_cast<Address>(mcontext.gregs[30]); | |
397 #elif V8_HOST_ARCH_PPC | |
398 state.pc = reinterpret_cast<Address>(ucontext->uc_mcontext.regs->nip); | |
399 state.sp = reinterpret_cast<Address>(ucontext->uc_mcontext.regs->gpr[PT_R1]); | |
400 state.fp = reinterpret_cast<Address>(ucontext->uc_mcontext.regs->gpr[PT_R31]); | |
401 #elif V8_HOST_ARCH_S390 | |
402 #if V8_TARGET_ARCH_32_BIT | |
403 // 31-bit target will have bit 0 (MSB) of the PSW set to denote addressing | |
404 // mode. This bit needs to be masked out to resolve actual address. | |
405 state.pc = | |
406 reinterpret_cast<Address>(ucontext->uc_mcontext.psw.addr & 0x7FFFFFFF); | |
407 #else | |
408 state.pc = reinterpret_cast<Address>(ucontext->uc_mcontext.psw.addr); | |
409 #endif // V8_TARGET_ARCH_32_BIT | |
410 state.sp = reinterpret_cast<Address>(ucontext->uc_mcontext.gregs[15]); | |
411 state.fp = reinterpret_cast<Address>(ucontext->uc_mcontext.gregs[11]); | |
412 #endif // V8_HOST_ARCH_* | |
413 #elif V8_OS_MACOSX | |
414 #if V8_HOST_ARCH_X64 | |
415 #if __DARWIN_UNIX03 | |
416 state.pc = reinterpret_cast<Address>(mcontext->__ss.__rip); | |
417 state.sp = reinterpret_cast<Address>(mcontext->__ss.__rsp); | |
418 state.fp = reinterpret_cast<Address>(mcontext->__ss.__rbp); | |
419 #else // !__DARWIN_UNIX03 | |
420 state.pc = reinterpret_cast<Address>(mcontext->ss.rip); | |
421 state.sp = reinterpret_cast<Address>(mcontext->ss.rsp); | |
422 state.fp = reinterpret_cast<Address>(mcontext->ss.rbp); | |
423 #endif // __DARWIN_UNIX03 | |
424 #elif V8_HOST_ARCH_IA32 | |
425 #if __DARWIN_UNIX03 | |
426 state.pc = reinterpret_cast<Address>(mcontext->__ss.__eip); | |
427 state.sp = reinterpret_cast<Address>(mcontext->__ss.__esp); | |
428 state.fp = reinterpret_cast<Address>(mcontext->__ss.__ebp); | |
429 #else // !__DARWIN_UNIX03 | |
430 state.pc = reinterpret_cast<Address>(mcontext->ss.eip); | |
431 state.sp = reinterpret_cast<Address>(mcontext->ss.esp); | |
432 state.fp = reinterpret_cast<Address>(mcontext->ss.ebp); | |
433 #endif // __DARWIN_UNIX03 | |
434 #endif // V8_HOST_ARCH_IA32 | |
435 #elif V8_OS_FREEBSD | |
436 #if V8_HOST_ARCH_IA32 | |
437 state.pc = reinterpret_cast<Address>(mcontext.mc_eip); | |
438 state.sp = reinterpret_cast<Address>(mcontext.mc_esp); | |
439 state.fp = reinterpret_cast<Address>(mcontext.mc_ebp); | |
440 #elif V8_HOST_ARCH_X64 | |
441 state.pc = reinterpret_cast<Address>(mcontext.mc_rip); | |
442 state.sp = reinterpret_cast<Address>(mcontext.mc_rsp); | |
443 state.fp = reinterpret_cast<Address>(mcontext.mc_rbp); | |
444 #elif V8_HOST_ARCH_ARM | |
445 state.pc = reinterpret_cast<Address>(mcontext.mc_r15); | |
446 state.sp = reinterpret_cast<Address>(mcontext.mc_r13); | |
447 state.fp = reinterpret_cast<Address>(mcontext.mc_r11); | |
448 #endif // V8_HOST_ARCH_* | |
449 #elif V8_OS_NETBSD | |
450 #if V8_HOST_ARCH_IA32 | |
451 state.pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_EIP]); | |
452 state.sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_ESP]); | |
453 state.fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_EBP]); | |
454 #elif V8_HOST_ARCH_X64 | |
455 state.pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_RIP]); | |
456 state.sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RSP]); | |
457 state.fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RBP]); | |
458 #endif // V8_HOST_ARCH_* | |
459 #elif V8_OS_OPENBSD | |
460 #if V8_HOST_ARCH_IA32 | |
461 state.pc = reinterpret_cast<Address>(ucontext->sc_eip); | |
462 state.sp = reinterpret_cast<Address>(ucontext->sc_esp); | |
463 state.fp = reinterpret_cast<Address>(ucontext->sc_ebp); | |
464 #elif V8_HOST_ARCH_X64 | |
465 state.pc = reinterpret_cast<Address>(ucontext->sc_rip); | |
466 state.sp = reinterpret_cast<Address>(ucontext->sc_rsp); | |
467 state.fp = reinterpret_cast<Address>(ucontext->sc_rbp); | |
468 #endif // V8_HOST_ARCH_* | |
469 #elif V8_OS_SOLARIS | |
470 state.pc = reinterpret_cast<Address>(mcontext.gregs[REG_PC]); | |
471 state.sp = reinterpret_cast<Address>(mcontext.gregs[REG_SP]); | |
472 state.fp = reinterpret_cast<Address>(mcontext.gregs[REG_FP]); | |
473 #elif V8_OS_QNX | |
474 #if V8_HOST_ARCH_IA32 | |
475 state.pc = reinterpret_cast<Address>(mcontext.cpu.eip); | |
476 state.sp = reinterpret_cast<Address>(mcontext.cpu.esp); | |
477 state.fp = reinterpret_cast<Address>(mcontext.cpu.ebp); | |
478 #elif V8_HOST_ARCH_ARM | |
479 state.pc = reinterpret_cast<Address>(mcontext.cpu.gpr[ARM_REG_PC]); | |
480 state.sp = reinterpret_cast<Address>(mcontext.cpu.gpr[ARM_REG_SP]); | |
481 state.fp = reinterpret_cast<Address>(mcontext.cpu.gpr[ARM_REG_FP]); | |
482 #endif // V8_HOST_ARCH_* | |
483 #elif V8_OS_AIX | |
484 state.pc = reinterpret_cast<Address>(mcontext.jmp_context.iar); | |
485 state.sp = reinterpret_cast<Address>(mcontext.jmp_context.gpr[1]); | |
486 state.fp = reinterpret_cast<Address>(mcontext.jmp_context.gpr[31]); | |
487 #endif // V8_OS_AIX | |
488 #endif // USE_SIMULATOR | |
489 sampler->SampleStack(state); | |
490 } | |
491 #endif // V8_OS_NACL | |
492 | |
493 #endif // USE_SIGNALS | |
494 | |
495 | |
496 class SamplerThread : public base::Thread { | |
497 public: | |
498 static const int kSamplerThreadStackSize = 64 * KB; | |
499 | |
500 explicit SamplerThread(int interval) | |
501 : Thread(base::Thread::Options("SamplerThread", kSamplerThreadStackSize)), | |
502 interval_(interval) {} | |
503 | |
504 static void SetUp() { if (!mutex_) mutex_ = new base::Mutex(); } | |
505 static void TearDown() { delete mutex_; mutex_ = NULL; } | |
506 | |
507 static void AddActiveSampler(Sampler* sampler) { | |
508 bool need_to_start = false; | |
509 base::LockGuard<base::Mutex> lock_guard(mutex_); | |
510 if (instance_ == NULL) { | |
511 // Start a thread that will send SIGPROF signal to VM threads, | |
512 // when CPU profiling will be enabled. | |
513 instance_ = new SamplerThread(sampler->interval()); | |
514 need_to_start = true; | |
515 } | |
516 | |
517 DCHECK(sampler->IsActive()); | |
518 DCHECK(instance_->interval_ == sampler->interval()); | |
519 | |
520 #if defined(USE_SIGNALS) | |
521 AddSampler(sampler); | |
522 #else | |
523 DCHECK(!instance_->active_samplers_.Contains(sampler)); | |
524 instance_->active_samplers_.Add(sampler); | |
525 #endif // USE_SIGNALS | |
526 | |
527 if (need_to_start) instance_->StartSynchronously(); | |
528 } | |
529 | |
530 static void RemoveSampler(Sampler* sampler) { | |
531 SamplerThread* instance_to_remove = NULL; | |
532 { | |
533 base::LockGuard<base::Mutex> lock_guard(mutex_); | |
534 | |
535 DCHECK(sampler->IsActive() || sampler->IsRegistered()); | |
536 #if defined(USE_SIGNALS) | |
537 { | |
538 AtomicGuard atomic_guard(&sampler_list_access_counter_); | |
539 // Remove sampler from map. | |
540 pthread_t thread_id = sampler->platform_data()->vm_tid(); | |
541 void* thread_key = ThreadKey(thread_id); | |
542 uint32_t thread_hash = ThreadHash(thread_id); | |
543 HashMap::Entry* entry = | |
544 thread_id_to_samplers_.Get().Lookup(thread_key, thread_hash); | |
545 DCHECK(entry != NULL); | |
546 SamplerList* samplers = reinterpret_cast<SamplerList*>(entry->value); | |
547 samplers->RemoveElement(sampler); | |
548 if (samplers->is_empty()) { | |
549 thread_id_to_samplers_.Pointer()->Remove(thread_key, thread_hash); | |
550 delete samplers; | |
551 } | |
552 if (thread_id_to_samplers_.Get().occupancy() == 0) { | |
553 instance_to_remove = instance_; | |
554 instance_ = NULL; | |
555 } | |
556 } | |
557 #else | |
558 bool removed = instance_->active_samplers_.RemoveElement(sampler); | |
559 DCHECK(removed); | |
560 USE(removed); | |
561 | |
562 // We cannot delete the instance immediately as we need to Join() the | |
563 // thread but we are holding mutex_ and the thread may try to acquire it. | |
564 if (instance_->active_samplers_.is_empty()) { | |
565 instance_to_remove = instance_; | |
566 instance_ = NULL; | |
567 } | |
568 #endif // USE_SIGNALS | |
569 } | |
570 | |
571 if (!instance_to_remove) return; | |
572 instance_to_remove->Join(); | |
573 delete instance_to_remove; | |
574 } | |
575 | |
576 // Unlike AddActiveSampler, this method only adds a sampler, | |
577 // but won't start the sampler thread. | |
578 static void RegisterSampler(Sampler* sampler) { | |
579 base::LockGuard<base::Mutex> lock_guard(mutex_); | |
580 #if defined(USE_SIGNALS) | |
581 AddSampler(sampler); | |
582 #endif // USE_SIGNALS | |
583 } | |
584 | |
585 // Implement Thread::Run(). | |
586 virtual void Run() { | |
587 while (true) { | |
588 { | |
589 base::LockGuard<base::Mutex> lock_guard(mutex_); | |
590 #if defined(USE_SIGNALS) | |
591 if (thread_id_to_samplers_.Get().occupancy() == 0) break; | |
592 if (SignalHandler::Installed()) { | |
593 for (HashMap::Entry *p = thread_id_to_samplers_.Get().Start(); | |
594 p != NULL; p = thread_id_to_samplers_.Get().Next(p)) { | |
595 #if V8_OS_AIX && V8_TARGET_ARCH_PPC64 | |
596 // on AIX64, cannot cast (void *) to pthread_t which is | |
597 // of type unsigned int (4bytes) | |
598 pthread_t thread_id = reinterpret_cast<intptr_t>(p->key); | |
599 #else | |
600 pthread_t thread_id = reinterpret_cast<pthread_t>(p->key); | |
601 #endif | |
602 pthread_kill(thread_id, SIGPROF); | |
603 } | |
604 } | |
605 #else | |
606 if (active_samplers_.is_empty()) break; | |
607 // When CPU profiling is enabled both JavaScript and C++ code is | |
608 // profiled. We must not suspend. | |
609 for (int i = 0; i < active_samplers_.length(); ++i) { | |
610 Sampler* sampler = active_samplers_.at(i); | |
611 if (!sampler->IsProfiling()) continue; | |
612 sampler->DoSample(); | |
613 } | |
614 #endif // USE_SIGNALS | |
615 } | |
616 base::OS::Sleep(base::TimeDelta::FromMilliseconds(interval_)); | |
617 } | |
618 } | |
619 | |
620 private: | |
621 // Protects the process wide state below. | |
622 static base::Mutex* mutex_; | |
623 static SamplerThread* instance_; | |
624 | |
625 const int interval_; | |
626 | |
627 #if defined(USE_SIGNALS) | |
628 struct HashMapCreateTrait { | |
629 static void Construct(HashMap* allocated_ptr) { | |
630 new (allocated_ptr) HashMap(HashMap::PointersMatch); | |
631 } | |
632 }; | |
633 friend class SignalHandler; | |
634 static base::LazyInstance<HashMap, HashMapCreateTrait>::type | |
635 thread_id_to_samplers_; | |
636 static base::AtomicValue<int> sampler_list_access_counter_; | |
637 static void AddSampler(Sampler* sampler) { | |
638 AtomicGuard atomic_guard(&sampler_list_access_counter_); | |
639 // Add sampler into map if needed. | |
640 pthread_t thread_id = sampler->platform_data()->vm_tid(); | |
641 HashMap::Entry *entry = | |
642 thread_id_to_samplers_.Pointer()->LookupOrInsert(ThreadKey(thread_id), | |
643 ThreadHash(thread_id)); | |
644 if (entry->value == NULL) { | |
645 SamplerList* samplers = new SamplerList(); | |
646 samplers->Add(sampler); | |
647 entry->value = samplers; | |
648 } else { | |
649 SamplerList* samplers = reinterpret_cast<SamplerList*>(entry->value); | |
650 if (!samplers->Contains(sampler)) { | |
651 samplers->Add(sampler); | |
652 } | |
653 } | |
654 } | |
655 #else | |
656 SamplerList active_samplers_; | |
657 #endif // USE_SIGNALS | |
658 | |
659 DISALLOW_COPY_AND_ASSIGN(SamplerThread); | |
660 }; | |
661 | |
662 | |
663 base::Mutex* SamplerThread::mutex_ = NULL; | |
664 SamplerThread* SamplerThread::instance_ = NULL; | |
665 #if defined(USE_SIGNALS) | |
666 base::LazyInstance<HashMap, SamplerThread::HashMapCreateTrait>::type | |
667 SamplerThread::thread_id_to_samplers_ = LAZY_INSTANCE_INITIALIZER; | |
668 base::AtomicValue<int> SamplerThread::sampler_list_access_counter_(0); | |
669 | |
670 // As Native Client does not support signal handling, profiling is disabled. | |
671 #if !V8_OS_NACL | |
672 void SignalHandler::HandleProfilerSignal(int signal, siginfo_t* info, | |
673 void* context) { | |
674 USE(info); | |
675 if (signal != SIGPROF) return; | |
676 AtomicGuard atomic_guard(&SamplerThread::sampler_list_access_counter_, false); | |
677 if (!atomic_guard.is_success()) return; | |
678 pthread_t thread_id = pthread_self(); | |
679 HashMap::Entry* entry = | |
680 SamplerThread::thread_id_to_samplers_.Pointer()->Lookup( | |
681 ThreadKey(thread_id), ThreadHash(thread_id)); | |
682 if (entry == NULL) | |
683 return; | |
684 SamplerList* samplers = reinterpret_cast<SamplerList*>(entry->value); | |
685 for (int i = 0; i < samplers->length(); ++i) { | |
686 Sampler* sampler = samplers->at(i); | |
687 CollectSample(context, sampler); | |
688 } | |
689 } | |
690 #endif // !V8_OS_NACL | |
691 #endif // USE_SIGNALs | |
692 | |
693 | |
694 void Sampler::SetUp() { | |
695 #if defined(USE_SIGNALS) | |
696 SignalHandler::SetUp(); | |
697 #endif | |
698 SamplerThread::SetUp(); | |
699 } | |
700 | |
701 | |
702 void Sampler::TearDown() { | |
703 SamplerThread::TearDown(); | |
704 #if defined(USE_SIGNALS) | |
705 SignalHandler::TearDown(); | |
706 #endif | |
707 } | |
708 | |
709 Sampler::Sampler(Isolate* isolate, int interval) | |
710 : isolate_(isolate), | |
711 interval_(interval), | |
712 profiling_(false), | |
713 has_processing_thread_(false), | |
714 active_(false), | |
715 registered_(false), | |
716 is_counting_samples_(false), | |
717 js_sample_count_(0), | |
718 external_sample_count_(0) { | |
719 data_ = new PlatformData; | |
720 } | |
721 | |
722 Sampler::~Sampler() { | |
723 DCHECK(!IsActive()); | |
724 if (IsRegistered()) { | |
725 SamplerThread::RemoveSampler(this); | |
726 } | |
727 delete data_; | |
728 } | |
729 | |
730 void Sampler::Start() { | |
731 DCHECK(!IsActive()); | |
732 SetActive(true); | |
733 SamplerThread::AddActiveSampler(this); | |
734 } | |
735 | |
736 | |
737 void Sampler::Stop() { | |
738 DCHECK(IsActive()); | |
739 SamplerThread::RemoveSampler(this); | |
740 SetActive(false); | |
741 SetRegistered(false); | |
742 } | |
743 | |
744 | |
745 void Sampler::IncreaseProfilingDepth() { | |
746 base::NoBarrier_AtomicIncrement(&profiling_, 1); | |
747 #if defined(USE_SIGNALS) | |
748 SignalHandler::IncreaseSamplerCount(); | |
749 #endif | |
750 } | |
751 | |
752 | |
753 void Sampler::DecreaseProfilingDepth() { | |
754 #if defined(USE_SIGNALS) | |
755 SignalHandler::DecreaseSamplerCount(); | |
756 #endif | |
757 base::NoBarrier_AtomicIncrement(&profiling_, -1); | |
758 } | |
759 | |
760 | |
761 void Sampler::SampleStack(const v8::RegisterState& state) { | |
762 TickSample* sample = isolate_->cpu_profiler()->StartTickSample(); | |
763 TickSample sample_obj; | |
764 if (sample == NULL) sample = &sample_obj; | |
765 sample->Init(isolate_, state, TickSample::kIncludeCEntryFrame, true); | |
766 if (is_counting_samples_ && !sample->timestamp.IsNull()) { | |
767 if (sample->state == JS) ++js_sample_count_; | |
768 if (sample->state == EXTERNAL) ++external_sample_count_; | |
769 } | |
770 Tick(sample); | |
771 if (sample != &sample_obj) { | |
772 isolate_->cpu_profiler()->FinishTickSample(); | |
773 } | |
774 } | |
775 | |
776 | |
777 #if defined(USE_SIGNALS) | |
778 | |
779 void Sampler::DoSample() { | |
780 if (!SignalHandler::Installed()) return; | |
781 if (!IsActive() && !IsRegistered()) { | |
782 SamplerThread::RegisterSampler(this); | |
783 SetRegistered(true); | |
784 } | |
785 pthread_kill(platform_data()->vm_tid(), SIGPROF); | |
786 } | |
787 | |
788 #elif V8_OS_WIN || V8_OS_CYGWIN | |
789 | |
790 void Sampler::DoSample() { | |
791 HANDLE profiled_thread = platform_data()->profiled_thread(); | |
792 if (profiled_thread == NULL) return; | |
793 | |
794 const DWORD kSuspendFailed = static_cast<DWORD>(-1); | |
795 if (SuspendThread(profiled_thread) == kSuspendFailed) return; | |
796 | |
797 // Context used for sampling the register state of the profiled thread. | |
798 CONTEXT context; | |
799 memset(&context, 0, sizeof(context)); | |
800 context.ContextFlags = CONTEXT_FULL; | |
801 if (GetThreadContext(profiled_thread, &context) != 0) { | |
802 v8::RegisterState state; | |
803 #if defined(USE_SIMULATOR) | |
804 if (!SimulatorHelper::FillRegisters(isolate(), &state)) { | |
805 ResumeThread(profiled_thread); | |
806 return; | |
807 } | |
808 #else | |
809 #if V8_HOST_ARCH_X64 | |
810 state.pc = reinterpret_cast<Address>(context.Rip); | |
811 state.sp = reinterpret_cast<Address>(context.Rsp); | |
812 state.fp = reinterpret_cast<Address>(context.Rbp); | |
813 #else | |
814 state.pc = reinterpret_cast<Address>(context.Eip); | |
815 state.sp = reinterpret_cast<Address>(context.Esp); | |
816 state.fp = reinterpret_cast<Address>(context.Ebp); | |
817 #endif | |
818 #endif // USE_SIMULATOR | |
819 SampleStack(state); | |
820 } | |
821 ResumeThread(profiled_thread); | |
822 } | |
823 | |
824 #endif // USE_SIGNALS | |
825 | |
826 | |
827 } // namespace internal | |
828 } // namespace v8 | |
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