Line data Source code
1 : // Copyright 2016 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/libsampler/sampler.h"
6 :
7 : #if V8_OS_POSIX && !V8_OS_CYGWIN && !V8_OS_FUCHSIA
8 :
9 : #define USE_SIGNALS
10 :
11 : #include <errno.h>
12 : #include <pthread.h>
13 : #include <signal.h>
14 : #include <sys/time.h>
15 : #include <atomic>
16 :
17 : #if !V8_OS_QNX && !V8_OS_AIX
18 : #include <sys/syscall.h> // NOLINT
19 : #endif
20 :
21 : #if V8_OS_MACOSX
22 : #include <mach/mach.h>
23 : // OpenBSD doesn't have <ucontext.h>. ucontext_t lives in <signal.h>
24 : // and is a typedef for struct sigcontext. There is no uc_mcontext.
25 : #elif !V8_OS_OPENBSD
26 : #include <ucontext.h>
27 : #endif
28 :
29 : #include <unistd.h>
30 :
31 : #elif V8_OS_WIN || V8_OS_CYGWIN
32 :
33 : #include "src/base/win32-headers.h"
34 :
35 : #elif V8_OS_FUCHSIA
36 :
37 : #include <zircon/process.h>
38 : #include <zircon/syscalls.h>
39 : #include <zircon/syscalls/debug.h>
40 : #include <zircon/types.h>
41 :
42 : // TODO(wez): Remove this once the Fuchsia SDK has rolled.
43 : #if defined(ZX_THREAD_STATE_REGSET0)
44 : #define ZX_THREAD_STATE_GENERAL_REGS ZX_THREAD_STATE_REGSET0
45 : zx_status_t zx_thread_read_state(zx_handle_t h, uint32_t k, void* b, size_t l) {
46 : uint32_t dummy_out_len = 0;
47 : return zx_thread_read_state(h, k, b, static_cast<uint32_t>(l),
48 : &dummy_out_len);
49 : }
50 : #if defined(__x86_64__)
51 : typedef zx_x86_64_general_regs_t zx_thread_state_general_regs_t;
52 : #else
53 : typedef zx_arm64_general_regs_t zx_thread_state_general_regs_t;
54 : #endif
55 : #endif // !defined(ZX_THREAD_STATE_GENERAL_REGS)
56 :
57 : #endif
58 :
59 : #include <algorithm>
60 : #include <vector>
61 : #include <map>
62 :
63 : #include "src/base/atomic-utils.h"
64 : #include "src/base/hashmap.h"
65 : #include "src/base/platform/platform.h"
66 :
67 : #if V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T)
68 :
69 : // Not all versions of Android's C library provide ucontext_t.
70 : // Detect this and provide custom but compatible definitions. Note that these
71 : // follow the GLibc naming convention to access register values from
72 : // mcontext_t.
73 : //
74 : // See http://code.google.com/p/android/issues/detail?id=34784
75 :
76 : #if defined(__arm__)
77 :
78 : typedef struct sigcontext mcontext_t;
79 :
80 : typedef struct ucontext {
81 : uint32_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(__aarch64__)
89 :
90 : typedef struct sigcontext mcontext_t;
91 :
92 : typedef struct ucontext {
93 : uint64_t uc_flags;
94 : struct ucontext *uc_link;
95 : stack_t uc_stack;
96 : mcontext_t uc_mcontext;
97 : // Other fields are not used by V8, don't define them here.
98 : } ucontext_t;
99 :
100 : #elif defined(__mips__)
101 : // MIPS version of sigcontext, for Android bionic.
102 : typedef struct {
103 : uint32_t regmask;
104 : uint32_t status;
105 : uint64_t pc;
106 : uint64_t gregs[32];
107 : uint64_t fpregs[32];
108 : uint32_t acx;
109 : uint32_t fpc_csr;
110 : uint32_t fpc_eir;
111 : uint32_t used_math;
112 : uint32_t dsp;
113 : uint64_t mdhi;
114 : uint64_t mdlo;
115 : uint32_t hi1;
116 : uint32_t lo1;
117 : uint32_t hi2;
118 : uint32_t lo2;
119 : uint32_t hi3;
120 : uint32_t lo3;
121 : } mcontext_t;
122 :
123 : typedef struct ucontext {
124 : uint32_t uc_flags;
125 : struct ucontext* uc_link;
126 : stack_t uc_stack;
127 : mcontext_t uc_mcontext;
128 : // Other fields are not used by V8, don't define them here.
129 : } ucontext_t;
130 :
131 : #elif defined(__i386__)
132 : // x86 version for Android.
133 : typedef struct {
134 : uint32_t gregs[19];
135 : void* fpregs;
136 : uint32_t oldmask;
137 : uint32_t cr2;
138 : } mcontext_t;
139 :
140 : typedef uint32_t kernel_sigset_t[2]; // x86 kernel uses 64-bit signal masks
141 : typedef struct ucontext {
142 : uint32_t uc_flags;
143 : struct ucontext* uc_link;
144 : stack_t uc_stack;
145 : mcontext_t uc_mcontext;
146 : // Other fields are not used by V8, don't define them here.
147 : } ucontext_t;
148 : enum { REG_EBP = 6, REG_ESP = 7, REG_EIP = 14 };
149 :
150 : #elif defined(__x86_64__)
151 : // x64 version for Android.
152 : typedef struct {
153 : uint64_t gregs[23];
154 : void* fpregs;
155 : uint64_t __reserved1[8];
156 : } mcontext_t;
157 :
158 : typedef struct ucontext {
159 : uint64_t uc_flags;
160 : struct ucontext *uc_link;
161 : stack_t uc_stack;
162 : mcontext_t uc_mcontext;
163 : // Other fields are not used by V8, don't define them here.
164 : } ucontext_t;
165 : enum { REG_RBP = 10, REG_RSP = 15, REG_RIP = 16 };
166 : #endif
167 :
168 : #endif // V8_OS_ANDROID && !defined(__BIONIC_HAVE_UCONTEXT_T)
169 :
170 :
171 : namespace v8 {
172 : namespace sampler {
173 :
174 : namespace {
175 :
176 : #if defined(USE_SIGNALS)
177 : typedef std::vector<Sampler*> SamplerList;
178 : typedef std::atomic_bool AtomicMutex;
179 :
180 : class AtomicGuard {
181 : public:
182 27873 : explicit AtomicGuard(AtomicMutex* atomic, bool is_blocking = true)
183 27873 : : atomic_(atomic), is_success_(false) {
184 27937 : do {
185 27937 : bool expected = false;
186 : // We have to use the strong version here for the case where is_blocking
187 : // is false, and we will only attempt the exchange once.
188 27937 : is_success_ = atomic->compare_exchange_strong(expected, true);
189 928 : } while (is_blocking && !is_success_);
190 27873 : }
191 :
192 : bool is_success() const { return is_success_; }
193 :
194 : ~AtomicGuard() {
195 27873 : if (!is_success_) return;
196 27873 : atomic_->store(false);
197 : }
198 :
199 : private:
200 : AtomicMutex* const atomic_;
201 : bool is_success_;
202 : };
203 :
204 : // Returns key for hash map.
205 : void* ThreadKey(pthread_t thread_id) {
206 27873 : return reinterpret_cast<void*>(thread_id);
207 : }
208 :
209 : // Returns hash value for hash map.
210 : uint32_t ThreadHash(pthread_t thread_id) {
211 : #if V8_OS_BSD
212 : return static_cast<uint32_t>(reinterpret_cast<intptr_t>(thread_id));
213 : #else
214 27873 : return static_cast<uint32_t>(thread_id);
215 : #endif
216 : }
217 :
218 : #endif // USE_SIGNALS
219 :
220 : } // namespace
221 :
222 : #if defined(USE_SIGNALS)
223 :
224 : class Sampler::PlatformData {
225 : public:
226 63661 : PlatformData() : vm_tid_(pthread_self()) {}
227 30003 : pthread_t vm_tid() const { return vm_tid_; }
228 :
229 : private:
230 : pthread_t vm_tid_;
231 : };
232 :
233 : // SamplerManager keeps a list of Samplers per thread, and allows the caller to
234 : // take a sample for every Sampler on the current thread.
235 : class SamplerManager {
236 : public:
237 : SamplerManager() = default;
238 :
239 : // Add |sampler| to the map if it is not already present.
240 432 : void AddSampler(Sampler* sampler) {
241 432 : AtomicGuard atomic_guard(&samplers_access_counter_);
242 : DCHECK(sampler->IsActive() || !sampler->IsRegistered());
243 432 : pthread_t thread_id = sampler->platform_data()->vm_tid();
244 : base::HashMap::Entry* entry =
245 : sampler_map_.LookupOrInsert(ThreadKey(thread_id),
246 864 : ThreadHash(thread_id));
247 : DCHECK_NOT_NULL(entry);
248 432 : if (entry->value == nullptr) {
249 431 : SamplerList* samplers = new SamplerList();
250 431 : samplers->push_back(sampler);
251 431 : entry->value = samplers;
252 : } else {
253 : SamplerList* samplers = reinterpret_cast<SamplerList*>(entry->value);
254 : auto it = std::find(samplers->begin(), samplers->end(), sampler);
255 1 : if (it == samplers->end()) samplers->push_back(sampler);
256 : }
257 432 : }
258 :
259 : // If |sampler| exists in the map, remove it and delete the SamplerList if
260 : // |sampler| was the last sampler in the list.
261 432 : void RemoveSampler(Sampler* sampler) {
262 432 : AtomicGuard atomic_guard(&samplers_access_counter_);
263 : DCHECK(sampler->IsActive() || sampler->IsRegistered());
264 432 : pthread_t thread_id = sampler->platform_data()->vm_tid();
265 432 : void* thread_key = ThreadKey(thread_id);
266 : uint32_t thread_hash = ThreadHash(thread_id);
267 432 : base::HashMap::Entry* entry = sampler_map_.Lookup(thread_key, thread_hash);
268 : DCHECK_NOT_NULL(entry);
269 432 : SamplerList* samplers = reinterpret_cast<SamplerList*>(entry->value);
270 : samplers->erase(std::remove(samplers->begin(), samplers->end(), sampler),
271 432 : samplers->end());
272 432 : if (samplers->empty()) {
273 431 : sampler_map_.Remove(thread_key, thread_hash);
274 862 : delete samplers;
275 : }
276 432 : }
277 :
278 : #if defined(USE_SIGNALS)
279 : // Take a sample for every sampler on the current thread. This function can
280 : // return without taking samples if AddSampler or RemoveSampler are being
281 : // concurrently called on any thread.
282 27009 : void DoSample(const v8::RegisterState& state) {
283 27009 : AtomicGuard atomic_guard(&samplers_access_counter_, false);
284 27009 : if (!atomic_guard.is_success()) return;
285 27009 : pthread_t thread_id = pthread_self();
286 : base::HashMap::Entry* entry =
287 27009 : sampler_map_.Lookup(ThreadKey(thread_id), ThreadHash(thread_id));
288 27009 : if (!entry) return;
289 27009 : SamplerList& samplers = *static_cast<SamplerList*>(entry->value);
290 :
291 81029 : for (Sampler* sampler : samplers) {
292 : Isolate* isolate = sampler->isolate();
293 : // We require a fully initialized and entered isolate.
294 27011 : if (isolate == nullptr || !isolate->IsInUse()) continue;
295 27002 : if (v8::Locker::IsActive() && !Locker::IsLocked(isolate)) continue;
296 27002 : sampler->SampleStack(state);
297 : }
298 : }
299 : #endif
300 :
301 27873 : static SamplerManager* instance() {
302 28037 : static base::LeakyObject<SamplerManager> instance;
303 27873 : return instance.get();
304 : }
305 :
306 : private:
307 : base::HashMap sampler_map_;
308 : AtomicMutex samplers_access_counter_;
309 : };
310 :
311 : #elif V8_OS_WIN || V8_OS_CYGWIN
312 :
313 : // ----------------------------------------------------------------------------
314 : // Win32 profiler support. On Cygwin we use the same sampler implementation as
315 : // on Win32.
316 :
317 : class Sampler::PlatformData {
318 : public:
319 : // Get a handle to the calling thread. This is the thread that we are
320 : // going to profile. We need to make a copy of the handle because we are
321 : // going to use it in the sampler thread. Using GetThreadHandle() will
322 : // not work in this case. We're using OpenThread because DuplicateHandle
323 : // for some reason doesn't work in Chrome's sandbox.
324 : PlatformData()
325 : : profiled_thread_(OpenThread(THREAD_GET_CONTEXT |
326 : THREAD_SUSPEND_RESUME |
327 : THREAD_QUERY_INFORMATION,
328 : false,
329 : GetCurrentThreadId())) {}
330 :
331 : ~PlatformData() {
332 : if (profiled_thread_ != nullptr) {
333 : CloseHandle(profiled_thread_);
334 : profiled_thread_ = nullptr;
335 : }
336 : }
337 :
338 : HANDLE profiled_thread() { return profiled_thread_; }
339 :
340 : private:
341 : HANDLE profiled_thread_;
342 : };
343 :
344 : #elif V8_OS_FUCHSIA
345 :
346 : class Sampler::PlatformData {
347 : public:
348 : PlatformData() {
349 : zx_handle_duplicate(zx_thread_self(), ZX_RIGHT_SAME_RIGHTS,
350 : &profiled_thread_);
351 : }
352 : ~PlatformData() {
353 : if (profiled_thread_ != ZX_HANDLE_INVALID) {
354 : zx_handle_close(profiled_thread_);
355 : profiled_thread_ = ZX_HANDLE_INVALID;
356 : }
357 : }
358 :
359 : zx_handle_t profiled_thread() { return profiled_thread_; }
360 :
361 : private:
362 : zx_handle_t profiled_thread_ = ZX_HANDLE_INVALID;
363 : };
364 :
365 : #endif // USE_SIGNALS
366 :
367 :
368 : #if defined(USE_SIGNALS)
369 : class SignalHandler {
370 : public:
371 61281 : static void SetUp() { if (!mutex_) mutex_ = new base::Mutex(); }
372 31878 : static void TearDown() {
373 31878 : delete mutex_;
374 31878 : mutex_ = nullptr;
375 31878 : }
376 :
377 778 : static void IncreaseSamplerCount() {
378 778 : base::MutexGuard lock_guard(mutex_);
379 778 : if (++client_count_ == 1) Install();
380 778 : }
381 :
382 773 : static void DecreaseSamplerCount() {
383 773 : base::MutexGuard lock_guard(mutex_);
384 773 : if (--client_count_ == 0) Restore();
385 773 : }
386 :
387 29139 : static bool Installed() {
388 29139 : base::MutexGuard lock_guard(mutex_);
389 58278 : return signal_handler_installed_;
390 : }
391 :
392 : private:
393 768 : static void Install() {
394 : struct sigaction sa;
395 768 : sa.sa_sigaction = &HandleProfilerSignal;
396 768 : sigemptyset(&sa.sa_mask);
397 : #if V8_OS_QNX
398 : sa.sa_flags = SA_SIGINFO;
399 : #else
400 768 : sa.sa_flags = SA_RESTART | SA_SIGINFO;
401 : #endif
402 : signal_handler_installed_ =
403 768 : (sigaction(SIGPROF, &sa, &old_signal_handler_) == 0);
404 768 : }
405 :
406 763 : static void Restore() {
407 763 : if (signal_handler_installed_) {
408 763 : sigaction(SIGPROF, &old_signal_handler_, nullptr);
409 763 : signal_handler_installed_ = false;
410 : }
411 763 : }
412 :
413 : static void FillRegisterState(void* context, RegisterState* regs);
414 : static void HandleProfilerSignal(int signal, siginfo_t* info, void* context);
415 :
416 : // Protects the process wide state below.
417 : static base::Mutex* mutex_;
418 : static int client_count_;
419 : static bool signal_handler_installed_;
420 : static struct sigaction old_signal_handler_;
421 : };
422 :
423 : base::Mutex* SignalHandler::mutex_ = nullptr;
424 : int SignalHandler::client_count_ = 0;
425 : struct sigaction SignalHandler::old_signal_handler_;
426 : bool SignalHandler::signal_handler_installed_ = false;
427 :
428 :
429 27009 : void SignalHandler::HandleProfilerSignal(int signal, siginfo_t* info,
430 : void* context) {
431 : USE(info);
432 27009 : if (signal != SIGPROF) return;
433 : v8::RegisterState state;
434 : FillRegisterState(context, &state);
435 27009 : SamplerManager::instance()->DoSample(state);
436 : }
437 :
438 0 : void SignalHandler::FillRegisterState(void* context, RegisterState* state) {
439 : // Extracting the sample from the context is extremely machine dependent.
440 : ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context);
441 : #if !(V8_OS_OPENBSD || (V8_OS_LINUX && (V8_HOST_ARCH_PPC || V8_HOST_ARCH_S390)))
442 : mcontext_t& mcontext = ucontext->uc_mcontext;
443 : #endif
444 : #if V8_OS_LINUX
445 : #if V8_HOST_ARCH_IA32
446 : state->pc = reinterpret_cast<void*>(mcontext.gregs[REG_EIP]);
447 : state->sp = reinterpret_cast<void*>(mcontext.gregs[REG_ESP]);
448 : state->fp = reinterpret_cast<void*>(mcontext.gregs[REG_EBP]);
449 : #elif V8_HOST_ARCH_X64
450 27009 : state->pc = reinterpret_cast<void*>(mcontext.gregs[REG_RIP]);
451 27009 : state->sp = reinterpret_cast<void*>(mcontext.gregs[REG_RSP]);
452 27009 : state->fp = reinterpret_cast<void*>(mcontext.gregs[REG_RBP]);
453 : #elif V8_HOST_ARCH_ARM
454 : #if V8_LIBC_GLIBC && !V8_GLIBC_PREREQ(2, 4)
455 : // Old GLibc ARM versions used a gregs[] array to access the register
456 : // values from mcontext_t.
457 : state->pc = reinterpret_cast<void*>(mcontext.gregs[R15]);
458 : state->sp = reinterpret_cast<void*>(mcontext.gregs[R13]);
459 : state->fp = reinterpret_cast<void*>(mcontext.gregs[R11]);
460 : #else
461 : state->pc = reinterpret_cast<void*>(mcontext.arm_pc);
462 : state->sp = reinterpret_cast<void*>(mcontext.arm_sp);
463 : state->fp = reinterpret_cast<void*>(mcontext.arm_fp);
464 : #endif // V8_LIBC_GLIBC && !V8_GLIBC_PREREQ(2, 4)
465 : #elif V8_HOST_ARCH_ARM64
466 : state->pc = reinterpret_cast<void*>(mcontext.pc);
467 : state->sp = reinterpret_cast<void*>(mcontext.sp);
468 : // FP is an alias for x29.
469 : state->fp = reinterpret_cast<void*>(mcontext.regs[29]);
470 : #elif V8_HOST_ARCH_MIPS
471 : state->pc = reinterpret_cast<void*>(mcontext.pc);
472 : state->sp = reinterpret_cast<void*>(mcontext.gregs[29]);
473 : state->fp = reinterpret_cast<void*>(mcontext.gregs[30]);
474 : #elif V8_HOST_ARCH_MIPS64
475 : state->pc = reinterpret_cast<void*>(mcontext.pc);
476 : state->sp = reinterpret_cast<void*>(mcontext.gregs[29]);
477 : state->fp = reinterpret_cast<void*>(mcontext.gregs[30]);
478 : #elif V8_HOST_ARCH_PPC
479 : #if V8_LIBC_GLIBC
480 : state->pc = reinterpret_cast<void*>(ucontext->uc_mcontext.regs->nip);
481 : state->sp =
482 : reinterpret_cast<void*>(ucontext->uc_mcontext.regs->gpr[PT_R1]);
483 : state->fp =
484 : reinterpret_cast<void*>(ucontext->uc_mcontext.regs->gpr[PT_R31]);
485 : #else
486 : // Some C libraries, notably Musl, define the regs member as a void pointer
487 : state->pc = reinterpret_cast<void*>(ucontext->uc_mcontext.gp_regs[32]);
488 : state->sp = reinterpret_cast<void*>(ucontext->uc_mcontext.gp_regs[1]);
489 : state->fp = reinterpret_cast<void*>(ucontext->uc_mcontext.gp_regs[31]);
490 : #endif
491 : #elif V8_HOST_ARCH_S390
492 : #if V8_TARGET_ARCH_32_BIT
493 : // 31-bit target will have bit 0 (MSB) of the PSW set to denote addressing
494 : // mode. This bit needs to be masked out to resolve actual address.
495 : state->pc =
496 : reinterpret_cast<void*>(ucontext->uc_mcontext.psw.addr & 0x7FFFFFFF);
497 : #else
498 : state->pc = reinterpret_cast<void*>(ucontext->uc_mcontext.psw.addr);
499 : #endif // V8_TARGET_ARCH_32_BIT
500 : state->sp = reinterpret_cast<void*>(ucontext->uc_mcontext.gregs[15]);
501 : state->fp = reinterpret_cast<void*>(ucontext->uc_mcontext.gregs[11]);
502 : #endif // V8_HOST_ARCH_*
503 : #elif V8_OS_MACOSX
504 : #if V8_HOST_ARCH_X64
505 : #if __DARWIN_UNIX03
506 : state->pc = reinterpret_cast<void*>(mcontext->__ss.__rip);
507 : state->sp = reinterpret_cast<void*>(mcontext->__ss.__rsp);
508 : state->fp = reinterpret_cast<void*>(mcontext->__ss.__rbp);
509 : #else // !__DARWIN_UNIX03
510 : state->pc = reinterpret_cast<void*>(mcontext->ss.rip);
511 : state->sp = reinterpret_cast<void*>(mcontext->ss.rsp);
512 : state->fp = reinterpret_cast<void*>(mcontext->ss.rbp);
513 : #endif // __DARWIN_UNIX03
514 : #elif V8_HOST_ARCH_IA32
515 : #if __DARWIN_UNIX03
516 : state->pc = reinterpret_cast<void*>(mcontext->__ss.__eip);
517 : state->sp = reinterpret_cast<void*>(mcontext->__ss.__esp);
518 : state->fp = reinterpret_cast<void*>(mcontext->__ss.__ebp);
519 : #else // !__DARWIN_UNIX03
520 : state->pc = reinterpret_cast<void*>(mcontext->ss.eip);
521 : state->sp = reinterpret_cast<void*>(mcontext->ss.esp);
522 : state->fp = reinterpret_cast<void*>(mcontext->ss.ebp);
523 : #endif // __DARWIN_UNIX03
524 : #endif // V8_HOST_ARCH_IA32
525 : #elif V8_OS_FREEBSD
526 : #if V8_HOST_ARCH_IA32
527 : state->pc = reinterpret_cast<void*>(mcontext.mc_eip);
528 : state->sp = reinterpret_cast<void*>(mcontext.mc_esp);
529 : state->fp = reinterpret_cast<void*>(mcontext.mc_ebp);
530 : #elif V8_HOST_ARCH_X64
531 : state->pc = reinterpret_cast<void*>(mcontext.mc_rip);
532 : state->sp = reinterpret_cast<void*>(mcontext.mc_rsp);
533 : state->fp = reinterpret_cast<void*>(mcontext.mc_rbp);
534 : #elif V8_HOST_ARCH_ARM
535 : state->pc = reinterpret_cast<void*>(mcontext.mc_r15);
536 : state->sp = reinterpret_cast<void*>(mcontext.mc_r13);
537 : state->fp = reinterpret_cast<void*>(mcontext.mc_r11);
538 : #endif // V8_HOST_ARCH_*
539 : #elif V8_OS_NETBSD
540 : #if V8_HOST_ARCH_IA32
541 : state->pc = reinterpret_cast<void*>(mcontext.__gregs[_REG_EIP]);
542 : state->sp = reinterpret_cast<void*>(mcontext.__gregs[_REG_ESP]);
543 : state->fp = reinterpret_cast<void*>(mcontext.__gregs[_REG_EBP]);
544 : #elif V8_HOST_ARCH_X64
545 : state->pc = reinterpret_cast<void*>(mcontext.__gregs[_REG_RIP]);
546 : state->sp = reinterpret_cast<void*>(mcontext.__gregs[_REG_RSP]);
547 : state->fp = reinterpret_cast<void*>(mcontext.__gregs[_REG_RBP]);
548 : #endif // V8_HOST_ARCH_*
549 : #elif V8_OS_OPENBSD
550 : #if V8_HOST_ARCH_IA32
551 : state->pc = reinterpret_cast<void*>(ucontext->sc_eip);
552 : state->sp = reinterpret_cast<void*>(ucontext->sc_esp);
553 : state->fp = reinterpret_cast<void*>(ucontext->sc_ebp);
554 : #elif V8_HOST_ARCH_X64
555 : state->pc = reinterpret_cast<void*>(ucontext->sc_rip);
556 : state->sp = reinterpret_cast<void*>(ucontext->sc_rsp);
557 : state->fp = reinterpret_cast<void*>(ucontext->sc_rbp);
558 : #endif // V8_HOST_ARCH_*
559 : #elif V8_OS_SOLARIS
560 : state->pc = reinterpret_cast<void*>(mcontext.gregs[REG_PC]);
561 : state->sp = reinterpret_cast<void*>(mcontext.gregs[REG_SP]);
562 : state->fp = reinterpret_cast<void*>(mcontext.gregs[REG_FP]);
563 : #elif V8_OS_QNX
564 : #if V8_HOST_ARCH_IA32
565 : state->pc = reinterpret_cast<void*>(mcontext.cpu.eip);
566 : state->sp = reinterpret_cast<void*>(mcontext.cpu.esp);
567 : state->fp = reinterpret_cast<void*>(mcontext.cpu.ebp);
568 : #elif V8_HOST_ARCH_ARM
569 : state->pc = reinterpret_cast<void*>(mcontext.cpu.gpr[ARM_REG_PC]);
570 : state->sp = reinterpret_cast<void*>(mcontext.cpu.gpr[ARM_REG_SP]);
571 : state->fp = reinterpret_cast<void*>(mcontext.cpu.gpr[ARM_REG_FP]);
572 : #endif // V8_HOST_ARCH_*
573 : #elif V8_OS_AIX
574 : state->pc = reinterpret_cast<void*>(mcontext.jmp_context.iar);
575 : state->sp = reinterpret_cast<void*>(mcontext.jmp_context.gpr[1]);
576 : state->fp = reinterpret_cast<void*>(mcontext.jmp_context.gpr[31]);
577 : #endif // V8_OS_AIX
578 0 : }
579 :
580 : #endif // USE_SIGNALS
581 :
582 :
583 61281 : void Sampler::SetUp() {
584 : #if defined(USE_SIGNALS)
585 61281 : SignalHandler::SetUp();
586 : #endif
587 61281 : }
588 :
589 :
590 31878 : void Sampler::TearDown() {
591 : #if defined(USE_SIGNALS)
592 31878 : SignalHandler::TearDown();
593 : #endif
594 31878 : }
595 :
596 63661 : Sampler::Sampler(Isolate* isolate)
597 : : is_counting_samples_(false),
598 : js_sample_count_(0),
599 : external_sample_count_(0),
600 : isolate_(isolate),
601 : profiling_(false),
602 : has_processing_thread_(false),
603 : active_(false),
604 63661 : registered_(false) {
605 127322 : data_ = new PlatformData;
606 63661 : }
607 :
608 773 : void Sampler::UnregisterIfRegistered() {
609 : #if defined(USE_SIGNALS)
610 773 : if (IsRegistered()) {
611 432 : SamplerManager::instance()->RemoveSampler(this);
612 : SetRegistered(false);
613 : }
614 : #endif
615 773 : }
616 :
617 63641 : Sampler::~Sampler() {
618 : DCHECK(!IsActive());
619 : DCHECK(!IsRegistered());
620 63641 : delete data_;
621 63641 : }
622 :
623 0 : void Sampler::Start() {
624 : DCHECK(!IsActive());
625 : SetActive(true);
626 : #if defined(USE_SIGNALS)
627 0 : SamplerManager::instance()->AddSampler(this);
628 : #endif
629 0 : }
630 :
631 :
632 0 : void Sampler::Stop() {
633 : #if defined(USE_SIGNALS)
634 0 : SamplerManager::instance()->RemoveSampler(this);
635 : #endif
636 : DCHECK(IsActive());
637 : SetActive(false);
638 : SetRegistered(false);
639 0 : }
640 :
641 :
642 778 : void Sampler::IncreaseProfilingDepth() {
643 778 : base::Relaxed_AtomicIncrement(&profiling_, 1);
644 : #if defined(USE_SIGNALS)
645 778 : SignalHandler::IncreaseSamplerCount();
646 : #endif
647 778 : }
648 :
649 :
650 773 : void Sampler::DecreaseProfilingDepth() {
651 : #if defined(USE_SIGNALS)
652 773 : SignalHandler::DecreaseSamplerCount();
653 : #endif
654 773 : base::Relaxed_AtomicIncrement(&profiling_, -1);
655 773 : }
656 :
657 :
658 : #if defined(USE_SIGNALS)
659 :
660 58278 : void Sampler::DoSample() {
661 58278 : if (!SignalHandler::Installed()) return;
662 58278 : if (!IsActive() && !IsRegistered()) {
663 432 : SamplerManager::instance()->AddSampler(this);
664 : SetRegistered(true);
665 : }
666 29139 : pthread_kill(platform_data()->vm_tid(), SIGPROF);
667 : }
668 :
669 : #elif V8_OS_WIN || V8_OS_CYGWIN
670 :
671 : void Sampler::DoSample() {
672 : HANDLE profiled_thread = platform_data()->profiled_thread();
673 : if (profiled_thread == nullptr) return;
674 :
675 : const DWORD kSuspendFailed = static_cast<DWORD>(-1);
676 : if (SuspendThread(profiled_thread) == kSuspendFailed) return;
677 :
678 : // Context used for sampling the register state of the profiled thread.
679 : CONTEXT context;
680 : memset(&context, 0, sizeof(context));
681 : context.ContextFlags = CONTEXT_FULL;
682 : if (GetThreadContext(profiled_thread, &context) != 0) {
683 : v8::RegisterState state;
684 : #if V8_HOST_ARCH_X64
685 : state.pc = reinterpret_cast<void*>(context.Rip);
686 : state.sp = reinterpret_cast<void*>(context.Rsp);
687 : state.fp = reinterpret_cast<void*>(context.Rbp);
688 : #elif V8_HOST_ARCH_ARM64
689 : state.pc = reinterpret_cast<void*>(context.Pc);
690 : state.sp = reinterpret_cast<void*>(context.Sp);
691 : state.fp = reinterpret_cast<void*>(context.Fp);
692 : #else
693 : state.pc = reinterpret_cast<void*>(context.Eip);
694 : state.sp = reinterpret_cast<void*>(context.Esp);
695 : state.fp = reinterpret_cast<void*>(context.Ebp);
696 : #endif
697 : SampleStack(state);
698 : }
699 : ResumeThread(profiled_thread);
700 : }
701 :
702 : #elif V8_OS_FUCHSIA
703 :
704 : void Sampler::DoSample() {
705 : zx_handle_t profiled_thread = platform_data()->profiled_thread();
706 : if (profiled_thread == ZX_HANDLE_INVALID) return;
707 :
708 : zx_handle_t suspend_token = ZX_HANDLE_INVALID;
709 : if (zx_task_suspend_token(profiled_thread, &suspend_token) != ZX_OK) return;
710 :
711 : // Wait for the target thread to become suspended, or to exit.
712 : // TODO(wez): There is currently no suspension count for threads, so there
713 : // is a risk that some other caller resumes the thread in-between our suspend
714 : // and wait calls, causing us to miss the SUSPENDED signal. We apply a 100ms
715 : // deadline to protect against hanging the sampler thread in this case.
716 : zx_signals_t signals = 0;
717 : zx_status_t suspended = zx_object_wait_one(
718 : profiled_thread, ZX_THREAD_SUSPENDED | ZX_THREAD_TERMINATED,
719 : zx_deadline_after(ZX_MSEC(100)), &signals);
720 : if (suspended != ZX_OK || (signals & ZX_THREAD_SUSPENDED) == 0) {
721 : zx_handle_close(suspend_token);
722 : return;
723 : }
724 :
725 : // Fetch a copy of its "general register" states.
726 : zx_thread_state_general_regs_t thread_state = {};
727 : if (zx_thread_read_state(profiled_thread, ZX_THREAD_STATE_GENERAL_REGS,
728 : &thread_state, sizeof(thread_state)) == ZX_OK) {
729 : v8::RegisterState state;
730 : #if V8_HOST_ARCH_X64
731 : state.pc = reinterpret_cast<void*>(thread_state.rip);
732 : state.sp = reinterpret_cast<void*>(thread_state.rsp);
733 : state.fp = reinterpret_cast<void*>(thread_state.rbp);
734 : #elif V8_HOST_ARCH_ARM64
735 : state.pc = reinterpret_cast<void*>(thread_state.pc);
736 : state.sp = reinterpret_cast<void*>(thread_state.sp);
737 : state.fp = reinterpret_cast<void*>(thread_state.r[29]);
738 : #endif
739 : SampleStack(state);
740 : }
741 :
742 : zx_handle_close(suspend_token);
743 : }
744 :
745 : // TODO(wez): Remove this once the Fuchsia SDK has rolled.
746 : #if defined(ZX_THREAD_STATE_REGSET0)
747 : #undef ZX_THREAD_STATE_GENERAL_REGS
748 : #endif
749 :
750 : #endif // USE_SIGNALS
751 :
752 : } // namespace sampler
753 : } // namespace v8
|
