src/hotspot/share/runtime/safepointMechanism.inline.hpp

rev 47413 : Introduce SafepointMechanism
rev 47415 : Add Thread Local handshakes and thread local polling

*** 25,47 ****
  #ifndef SHARE_VM_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP
  #define SHARE_VM_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP
  
  #include "runtime/safepointMechanism.hpp"
  #include "runtime/safepoint.hpp"
! #include "runtime/thread.hpp"
  
  
  bool SafepointMechanism::global_poll() {
    return SafepointSynchronize::do_call_back();
  }
  
! bool SafepointMechanism::poll() {
    return global_poll();
  }
  
  void SafepointMechanism::block_if_requested(JavaThread *thread) {
    if (global_poll()) {
      SafepointSynchronize::block(thread);
    }
  }
  
  #endif // SHARE_VM_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP
--- 25,92 ----
  #ifndef SHARE_VM_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP
  #define SHARE_VM_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP
  
  #include "runtime/safepointMechanism.hpp"
  #include "runtime/safepoint.hpp"
! #include "runtime/thread.inline.hpp"
  
+ bool SafepointMechanism::local_poll_armed(JavaThread* thread) {
+   const intptr_t poll_word = reinterpret_cast<intptr_t>(thread->get_polling_page());
+   return mask_bits_are_true(poll_word, poll_bit());
+ }
  
  bool SafepointMechanism::global_poll() {
    return SafepointSynchronize::do_call_back();
  }
  
! bool SafepointMechanism::local_poll(Thread* thread) {
!   // Mutexes can be taken but none JavaThread. These cannot have handshakes
!   // operation but they must stop for safepoints.
!   if (thread->is_Java_thread()) {
!     return local_poll_armed((JavaThread*)thread);
!   } else {
!     return global_poll();
!   }
! }
! 
! bool SafepointMechanism::poll(Thread* thread) {
!   if (uses_thread_local_poll()) {
!     return local_poll(thread);
!   } else {
      return global_poll();
+   }
+ }
+ 
+ void SafepointMechanism::block_if_requested_local_poll(JavaThread *thread) {
+   bool armed = local_poll_armed(thread); // load acquire, polling page -> op / global state
+   if(armed) {
+     // We could be armed for either a handshake operation or a safepoint
+     if (thread->has_handshake()) {
+       thread->handshake_process_by_self();
+     } else {
+       if (global_poll()) {
+         SafepointSynchronize::block(thread);
+       }
+     }
+   }
  }
  
  void SafepointMechanism::block_if_requested(JavaThread *thread) {
+   if (uses_thread_local_poll()) {
+     block_if_requested_local_poll(thread);
+   } else {
+     // If we don't have per thread poll this could a handshake or a safepoint
      if (global_poll()) {
        SafepointSynchronize::block(thread);
      }
+   }
+ }
+ 
+ void SafepointMechanism::arm_local_poll(JavaThread* thread) {
+   thread->set_polling_page(poll_armed_value());
+ }
+ 
+ void SafepointMechanism::disarm_local_poll(JavaThread* thread) {
+   thread->set_polling_page(poll_disarmed_value());
  }
  
  #endif // SHARE_VM_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP