/*

 * Copyright (c) 1997, 2013, 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

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 */

#ifndef SHARE_VM_RUNTIME_SWEEPER_HPP

#define SHARE_VM_RUNTIME_SWEEPER_HPP

// An NmethodSweeper is an incremental cleaner for:

//    - cleanup inline caches

class NMethodSweeper : public AllStatic {

  static long      _traversals;      // Stack scan count, also sweep ID.

  static nmethod*  _current;         // Current nmethod

  static int       _seen;            // Nof. nmethod we have currently processed in current pass of CodeCache

  static int       _flushed_count;   // Nof. nmethods flushed in current sweep

  static int       _zombified_count; // Nof. nmethods made zombie in current sweep

  static int       _marked_count;    // Nof. nmethods marked for reclaim in current sweep

  static volatile int  _invocations;   // No. of invocations left until we are completed with this pass

  static volatile int  _sweep_started; // Flag to control conc sweeper

  static int       _not_entrant_seen_on_stack; // Number of not entrant nmethod were are still on stack

  // Stat counters

  static int       _total_nof_methods_reclaimed;  // Accumulated nof methods flushed

  static jlong     _total_time_sweeping;          // Accumulated time sweeping

  static jlong     _total_time_this_sweep;        // Total time this sweep

  static jlong     _peak_sweep_time;              // Peak time for a full sweep

  static jlong     _peak_sweep_fraction_time;     // Peak time sweeping one fraction

  static void release_nmethod(nmethod* nm);

  static bool sweep_in_progress();

 public:

  static long traversal_count()              { return _traversals; }

  static int  total_nof_methods_reclaimed()  { return _total_nof_methods_reclaimed; }

  static jlong total_time_sweeping()         { return _total_time_sweeping; }

  static jlong peak_sweep_time()             { return _peak_sweep_time; }

  static jlong peak_sweep_fraction_time()    { return _peak_sweep_fraction_time; }

#ifdef ASSERT

  static bool is_sweeping(nmethod* which) { return _current == which; }

  // Keep track of sweeper activity in the ring buffer

  static void record_sweep(nmethod* nm, int line);

  static void report_events(int id, address entry);

  static void report_events();

#endif

    // Request a new sweep of the code cache from the beginning. No

    // need to synchronize the setting of this flag since it only

    // changes to false at safepoint so we can never overwrite it with false.

  }

};

#endif // SHARE_VM_RUNTIME_SWEEPER_HPP