Get rid or heap allocation in stack sampler to avoid deadlocks.

src/platform.h

 // Copyright 2006-2008 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 448 matching lines @@
 // the thread that created it.
 
 // TickSample captures the information collected for each sample.
 class TickSample {
  public:
   TickSample() : pc(0), sp(0), fp(0), state(OTHER) {}
   unsigned int pc;  // Instruction pointer.
   unsigned int sp;  // Stack pointer.
   unsigned int fp;  // Frame pointer.
   StateTag state;   // The state of the VM.
-  SmartPointer<Address> stack;  // Call stack, null-terminated.
-
-  inline TickSample& operator=(const TickSample& rhs) {
-    if (this == &rhs) return *this;
-    pc = rhs.pc;
-    sp = rhs.sp;
-    fp = rhs.fp;
-    state = rhs.state;
-    DeleteArray(stack.Detach());
-    stack = rhs.stack;
-    return *this;
-  }
-
-  inline void InitStack(int depth) {
-    if (depth) {
-      stack = SmartPointer<Address>(NewArray<Address>(depth + 1));
-      // null-terminate
-      stack[depth] = 0;
-    }
-  }
+  static const int kMaxFramesCount = 5;
+  EmbeddedVector<Address, kMaxFramesCount> stack;  // Call stack.
+  int frames_count;  // Number of captured frames.
 };
 
 class Sampler {
  public:
   // Initialize sampler.
   explicit Sampler(int interval, bool profiling);
   virtual ~Sampler();
 
   // This method is called for each sampling period with the current
   // program counter.
@@ skipping 16 matching lines @@
   bool active_;
   PlatformData* data_;  // Platform specific data.
   DISALLOW_IMPLICIT_CONSTRUCTORS(Sampler);
 };
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal
 
 #endif  // V8_PLATFORM_H_