1 /*
   2  * Copyright (c) 2017, 2020, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP
  26 #define SHARE_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP
  27 
  28 #include "runtime/safepointMechanism.hpp"
  29 #include "runtime/safepoint.hpp"
  30 #include "runtime/thread.inline.hpp"
  31 
  32 bool SafepointMechanism::local_poll_armed(JavaThread* thread) {
  33   const intptr_t poll_word = reinterpret_cast<intptr_t>(thread->get_polling_page());
  34   return mask_bits_are_true(poll_word, poll_bit());
  35 }
  36 
  37 bool SafepointMechanism::global_poll() {
  38   return (SafepointSynchronize::_state != SafepointSynchronize::_not_synchronized);
  39 }
  40 
  41 bool SafepointMechanism::local_poll(Thread* thread) {
  42   if (thread->is_Java_thread()) {
  43     return local_poll_armed((JavaThread*)thread);
  44   } else {
  45     // If the poll is on a non-java thread we can only check the global state.
  46     return global_poll();
  47   }
  48 }
  49 
  50 bool SafepointMechanism::should_block(Thread* thread) {
  51   return local_poll(thread);
  52 }
  53 
  54 void SafepointMechanism::block_if_requested(JavaThread *thread) {
  55   if (!local_poll_armed(thread)) {
  56     return;
  57   }
  58   block_if_requested_slow(thread);
  59 }
  60 
  61 void SafepointMechanism::arm_local_poll(JavaThread* thread) {
  62   thread->set_polling_page(poll_armed_value());
  63 }
  64 
  65 void SafepointMechanism::disarm_local_poll(JavaThread* thread) {
  66   thread->set_polling_page(poll_disarmed_value());
  67 }
  68 
  69 void SafepointMechanism::arm_local_poll_release(JavaThread* thread) {
  70   thread->set_polling_page_release(poll_armed_value());
  71 }
  72 
  73 void SafepointMechanism::disarm_local_poll_release(JavaThread* thread) {
  74   thread->set_polling_page_release(poll_disarmed_value());
  75 }
  76 
  77 #endif // SHARE_RUNTIME_SAFEPOINTMECHANISM_INLINE_HPP