src/hotspot/share/services/threadIdTable.hpp
author dtitov
Wed, 25 Sep 2019 11:10:05 -0700
changeset 58340 f4abe950c3b0
child 58504 94dd00d2da29
permissions -rw-r--r--
8185005: Improve performance of ThreadMXBean.getThreadInfo(long ids[], int maxDepth) Reviewed-by: sspitsyn, dholmes, dcubed, rehn


/*
* Copyright (c) 2019, 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.
*
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#ifndef SHARE_SERVICES_THREADIDTABLE_HPP
#define SHARE_SERVICES_THREADIDTABLE_HPP

#include "memory/allocation.hpp"

class JavaThread;
class ThreadsList;
class ThreadIdTableConfig;

class ThreadIdTable : public AllStatic {
  friend class ThreadIdTableConfig;

  static volatile bool _is_initialized;

public:
  // Initialization
  static void lazy_initialize(const ThreadsList* threads);
  static bool is_initialized() { return _is_initialized; }

  // Lookup and list management
  static JavaThread* find_thread_by_tid(jlong tid);
  static JavaThread* add_thread(jlong tid, JavaThread* thread);
  static bool remove_thread(jlong tid);

private:
  static void create_table(size_t size);

  static size_t table_size();
  static double get_load_factor();
  static void grow_if_required();
  static void grow(JavaThread* jt);

  static void item_added();
  static void item_removed();
};

#endif // SHARE_SERVICES_THREADIDTABLE_HPP