1 /*
   2  * Copyright (c) 2017, 2019, 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_THREADSMR_INLINE_HPP
  26 #define SHARE_RUNTIME_THREADSMR_INLINE_HPP
  27 
  28 #include "runtime/atomic.hpp"
  29 #include "runtime/prefetch.inline.hpp"
  30 #include "runtime/thread.inline.hpp"
  31 #include "runtime/threadSMR.hpp"
  32 
  33 // Devirtualize known thread closure types.
  34 template <class T>
  35 inline void ThreadsList::threads_do_dispatch(T *cl, JavaThread *const thread) const {
  36   cl->T::do_thread(thread);
  37 }
  38 
  39 template <>
  40 inline void ThreadsList::threads_do_dispatch<ThreadClosure>(ThreadClosure *cl, JavaThread *const thread) const {
  41   cl->do_thread(thread);
  42 }
  43 
  44 template <class T>
  45 inline void ThreadsList::threads_do(T *cl) const {
  46   const intx scan_interval = PrefetchScanIntervalInBytes;
  47   JavaThread *const *const end = _threads + _length;
  48   for (JavaThread *const *current_p = _threads; current_p != end; current_p++) {
  49     Prefetch::read((void*)current_p, scan_interval);
  50     JavaThread *const current = *current_p;
  51     threads_do_dispatch(cl, current);
  52   }
  53 }
  54 
  55 // These three inlines are private to ThreadsSMRSupport, but
  56 // they are called by public inline update_tlh_stats() below:
  57 
  58 inline void ThreadsSMRSupport::add_tlh_times(uint add_value) {
  59   Atomic::add(add_value, &_tlh_times);
  60 }
  61 
  62 inline void ThreadsSMRSupport::inc_tlh_cnt() {
  63   Atomic::inc(&_tlh_cnt);
  64 }
  65 
  66 inline void ThreadsSMRSupport::update_tlh_time_max(uint new_value) {
  67   while (true) {
  68     uint cur_value = _tlh_time_max;
  69     if (new_value <= cur_value) {
  70       // No need to update max value so we're done.
  71       break;
  72     }
  73     if (Atomic::cmpxchg(new_value, &_tlh_time_max, cur_value) == cur_value) {
  74       // Updated max value so we're done. Otherwise try it all again.
  75       break;
  76     }
  77   }
  78 }
  79 
  80 inline ThreadsList* ThreadsSMRSupport::get_java_thread_list() {
  81   return (ThreadsList*)Atomic::load_acquire(&_java_thread_list);
  82 }
  83 
  84 inline bool ThreadsSMRSupport::is_a_protected_JavaThread_with_lock(JavaThread *thread) {
  85   MutexLocker ml(Threads_lock->owned_by_self() ? NULL : Threads_lock);
  86   return is_a_protected_JavaThread(thread);
  87 }
  88 
  89 inline void ThreadsSMRSupport::update_tlh_stats(uint millis) {
  90   ThreadsSMRSupport::inc_tlh_cnt();
  91   ThreadsSMRSupport::add_tlh_times(millis);
  92   ThreadsSMRSupport::update_tlh_time_max(millis);
  93 }
  94 
  95 #endif // SHARE_RUNTIME_THREADSMR_INLINE_HPP