Revert r12889 due to Webkit test failures.

src/platform-linux.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1004 matching lines @@
 #if defined(__ANDROID__)
   // Android's C library provides gettid(2).
   return gettid();
 #else
   // Glibc doesn't provide a wrapper for gettid(2).
   return syscall(SYS_gettid);
 #endif
 }
 
 
+static void ProfilerSignalHandler(int signal, siginfo_t* info, void* context) {
+  USE(info);
+  if (signal != SIGPROF) return;
+  Isolate* isolate = Isolate::UncheckedCurrent();
+  if (isolate == NULL || !isolate->IsInitialized() || !isolate->IsInUse()) {
+    // We require a fully initialized and entered isolate.
+    return;
+  }
+  if (v8::Locker::IsActive() &&
+      !isolate->thread_manager()->IsLockedByCurrentThread()) {
+    return;
+  }
+
+  Sampler* sampler = isolate->logger()->sampler();
+  if (sampler == NULL || !sampler->IsActive()) return;
+
+  TickSample sample_obj;
+  TickSample* sample = CpuProfiler::TickSampleEvent(isolate);
+  if (sample == NULL) sample = &sample_obj;
+
+  // Extracting the sample from the context is extremely machine dependent.
+  ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context);
+  mcontext_t& mcontext = ucontext->uc_mcontext;
+  sample->state = isolate->current_vm_state();
+#if V8_HOST_ARCH_IA32
+  sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]);
+  sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]);
+  sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]);
+#elif V8_HOST_ARCH_X64
+  sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_RIP]);
+  sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_RSP]);
+  sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_RBP]);
+#elif V8_HOST_ARCH_ARM
+#if defined(__GLIBC__) && !defined(__UCLIBC__) && \
+    (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
+  // Old GLibc ARM versions used a gregs[] array to access the register
+  // values from mcontext_t.
+  sample->pc = reinterpret_cast<Address>(mcontext.gregs[R15]);
+  sample->sp = reinterpret_cast<Address>(mcontext.gregs[R13]);
+  sample->fp = reinterpret_cast<Address>(mcontext.gregs[R11]);
+#else
+  sample->pc = reinterpret_cast<Address>(mcontext.arm_pc);
+  sample->sp = reinterpret_cast<Address>(mcontext.arm_sp);
+  sample->fp = reinterpret_cast<Address>(mcontext.arm_fp);
+#endif  // defined(__GLIBC__) && !defined(__UCLIBC__) &&
+        // (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
+#elif V8_HOST_ARCH_MIPS
+  sample->pc = reinterpret_cast<Address>(mcontext.pc);
+  sample->sp = reinterpret_cast<Address>(mcontext.gregs[29]);
+  sample->fp = reinterpret_cast<Address>(mcontext.gregs[30]);
+#endif  // V8_HOST_ARCH_*
+  sampler->SampleStack(sample);
+  sampler->Tick(sample);
+}
+
+
 class Sampler::PlatformData : public Malloced {
  public:
   PlatformData() : vm_tid_(GetThreadID()) {}
 
   int vm_tid() const { return vm_tid_; }
 
  private:
   const int vm_tid_;
 };
 
 
-static void ProfilerSignalHandler(int signal, siginfo_t* info, void* context);
-
-
 class SignalSender : public Thread {
  public:
   enum SleepInterval {
     HALF_INTERVAL,
     FULL_INTERVAL
   };
 
   static const int kSignalSenderStackSize = 64 * KB;
 
   explicit SignalSender(int interval)
@@ skipping 13 matching lines @@
         (sigaction(SIGPROF, &sa, &old_signal_handler_) == 0);
   }
 
   static void RestoreSignalHandler() {
     if (signal_handler_installed_) {
       sigaction(SIGPROF, &old_signal_handler_, 0);
       signal_handler_installed_ = false;
     }
   }
 
-  static void CallOldSignalHandler(int signal, siginfo_t* info, void* context) {
-    if (signal_handler_installed_ && old_signal_handler_.sa_sigaction)
-      old_signal_handler_.sa_sigaction(signal, info, context);
-  }
-
   static void AddActiveSampler(Sampler* sampler) {
     ScopedLock lock(mutex_);
     SamplerRegistry::AddActiveSampler(sampler);
     if (instance_ == NULL) {
       // Start a thread that will send SIGPROF signal to VM threads,
       // when CPU profiling will be enabled.
       instance_ = new SignalSender(sampler->interval());
       instance_->Start();
     } else {
       ASSERT(instance_->interval_ == sampler->interval());
@@ skipping 113 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(SignalSender);
 };
 
 
 Mutex* SignalSender::mutex_ = NULL;
 SignalSender* SignalSender::instance_ = NULL;
 struct sigaction SignalSender::old_signal_handler_;
 bool SignalSender::signal_handler_installed_ = false;
 
 
-static void ProfilerSignalHandler(int signal, siginfo_t* info, void* context) {
-  USE(info);
-  if (signal != SIGPROF) return;
-  SignalSender::CallOldSignalHandler(signal, info, context);
-  Isolate* isolate = Isolate::UncheckedCurrent();
-  if (isolate == NULL || !isolate->IsInitialized() || !isolate->IsInUse()) {
-    // We require a fully initialized and entered isolate.
-    return;
-  }
-  if (v8::Locker::IsActive() &&
-      !isolate->thread_manager()->IsLockedByCurrentThread()) {
-    return;
-  }
-
-  Sampler* sampler = isolate->logger()->sampler();
-  if (sampler == NULL || !sampler->IsActive()) return;
-
-  TickSample sample_obj;
-  TickSample* sample = CpuProfiler::TickSampleEvent(isolate);
-  if (sample == NULL) sample = &sample_obj;
-
-  // Extracting the sample from the context is extremely machine dependent.
-  ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context);
-  mcontext_t& mcontext = ucontext->uc_mcontext;
-  sample->state = isolate->current_vm_state();
-#if V8_HOST_ARCH_IA32
-  sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]);
-  sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]);
-  sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]);
-#elif V8_HOST_ARCH_X64
-  sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_RIP]);
-  sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_RSP]);
-  sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_RBP]);
-#elif V8_HOST_ARCH_ARM
-#if defined(__GLIBC__) && !defined(__UCLIBC__) && \
-    (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
-  // Old GLibc ARM versions used a gregs[] array to access the register
-  // values from mcontext_t.
-  sample->pc = reinterpret_cast<Address>(mcontext.gregs[R15]);
-  sample->sp = reinterpret_cast<Address>(mcontext.gregs[R13]);
-  sample->fp = reinterpret_cast<Address>(mcontext.gregs[R11]);
-#else
-  sample->pc = reinterpret_cast<Address>(mcontext.arm_pc);
-  sample->sp = reinterpret_cast<Address>(mcontext.arm_sp);
-  sample->fp = reinterpret_cast<Address>(mcontext.arm_fp);
-#endif  // defined(__GLIBC__) && !defined(__UCLIBC__) &&
-        // (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
-#elif V8_HOST_ARCH_MIPS
-  sample->pc = reinterpret_cast<Address>(mcontext.pc);
-  sample->sp = reinterpret_cast<Address>(mcontext.gregs[29]);
-  sample->fp = reinterpret_cast<Address>(mcontext.gregs[30]);
-#endif  // V8_HOST_ARCH_*
-  sampler->SampleStack(sample);
-  sampler->Tick(sample);
-}
-
-
 void OS::SetUp() {
   // Seed the random number generator. We preserve microsecond resolution.
   uint64_t seed = Ticks() ^ (getpid() << 16);
   srandom(static_cast<unsigned int>(seed));
   limit_mutex = CreateMutex();
 
 #ifdef __arm__
   // When running on ARM hardware check that the EABI used by V8 and
   // by the C code is the same.
   bool hard_float = OS::ArmUsingHardFloat();
@@ skipping 45 matching lines @@
 
 
 void Sampler::Stop() {
   ASSERT(IsActive());
   SignalSender::RemoveActiveSampler(this);
   SetActive(false);
 }
 
 
 } }  // namespace v8::internal