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src/hotspot/share/runtime/safepointMechanism.hpp

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rev 47413 : Introduce SafepointMechanism
rev 47414 : Move polling page allocation to SafepointMechanism initialization
rev 47415 : Add Thread Local handshakes and thread local polling

@@ -28,29 +28,63 @@
 #include "runtime/globals.hpp"
 #include "utilities/globalDefinitions.hpp"
 #include "utilities/macros.hpp"
 #include "utilities/sizes.hpp"
 
-class JavaThread;
-
 // This is the abstracted interface for the safepoint implementation
 class SafepointMechanism : public AllStatic {
+  enum PollingType {
+    _global_page_poll,
+    _thread_local_poll
+  };
+  static PollingType _polling_type;
+  static void* _poll_armed_value;
+  static void* _poll_disarmed_value;
+  static void set_uses_thread_local_poll()            { _polling_type     = _thread_local_poll; }
+
+  static void* poll_armed_value()                     { return _poll_armed_value; }
+  static void* poll_disarmed_value()                  { return _poll_disarmed_value; }
+
+  static inline bool local_poll_armed(JavaThread* thread);
+
+  static inline bool local_poll(Thread* thread);
   static inline bool global_poll();
 
+  static inline void block_if_requested_local_poll(JavaThread *thread);
+
   static void default_initialize();
   static void initialize_serialize_page();
 
   static void pd_initialize() NOT_AIX({ default_initialize(); });
 
+  // By adding 8 to the base address of the protected polling page we can differentiate
+  // between the armed and disarmed value by masking out this bit.
+  const static intptr_t _poll_bit = 8;
 public:
+  static intptr_t poll_bit() { return _poll_bit; }
+
+  static bool uses_global_page_poll() { return _polling_type == _global_page_poll; }
+  static bool uses_thread_local_poll() { return _polling_type == _thread_local_poll; }
+
+  static bool supports_thread_local_poll() {
+#if defined(AMD64) || defined(SPARC)
+    return true;
+#else
+    return false;
+#endif
+  }
 
   // Call this method to see if this thread has depending poll and appropriate action should be taken
-  static inline bool poll();
+  static inline bool poll(Thread* thread);
 
   // Blocks a thread until safepoint is completed
   static inline void block_if_requested(JavaThread* thread);
 
+  static inline void arm_local_poll(JavaThread* thread);
+  static inline void disarm_local_poll(JavaThread* thread);
+
   // Setup the selected safepoint mechanism
   static void initialize();
+  static void initialize_header(JavaThread* thread);
 };
 
 #endif // SHARE_VM_RUNTIME_SAFEPOINTMECHANISM_HPP
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