/*

 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

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 */

#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) {

  if (thread->is_Java_thread()) {

    return local_poll_armed((JavaThread*)thread);

  } else {

    // If the poll is on a non-java thread we can only check the global state.

    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 (global_poll()) {

      SafepointSynchronize::block(thread);

    }

    if (thread->has_handshake()) {

      thread->handshake_process_by_self();

    }

  }

}

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