/*

 * Copyright (c) 2012, 2018, 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_GC_SHARED_GCTIMER_HPP

#define SHARE_VM_GC_SHARED_GCTIMER_HPP

#include "memory/allocation.hpp"

#include "utilities/macros.hpp"

#include "utilities/ticks.hpp"

class ConcurrentPhase;

class GCPhase;

class PausePhase;

template <class E> class GrowableArray;

class PhaseVisitor {

 public:

  virtual void visit(GCPhase* phase) = 0;

};

class GCPhase {

 public:

  enum PhaseType {

    PausePhaseType      = 0,

    ConcurrentPhaseType = 1

  };

 private:

  const char* _name;

  int _level;

  Ticks _start;

  Ticks _end;

  PhaseType _type;

 public:

  void set_name(const char* name) { _name = name; }

  const char* name() const { return _name; }

  int level() const { return _level; }

  void set_level(int level) { _level = level; }

  const Ticks start() const { return _start; }

  void set_start(const Ticks& time) { _start = time; }

  const Ticks end() const { return _end; }

  void set_end(const Ticks& time) { _end = time; }

  PhaseType type() const { return _type; }

  void set_type(PhaseType type) { _type = type; }

  void accept(PhaseVisitor* visitor) {

    visitor->visit(this);

  }

};

class PhasesStack {

 public:

  // Set to 6, since Reference processing needs it.

  static const int PHASE_LEVELS = 6;

 private:

  int _phase_indices[PHASE_LEVELS];

  int _next_phase_level;

 public:

  PhasesStack() { clear(); }

  void clear();

  void push(int phase_index);

  int pop();

  int count() const;

};

class TimePartitions {

  static const int INITIAL_CAPACITY = 10;

  GrowableArray<GCPhase>* _phases;

  PhasesStack _active_phases;

  Tickspan _sum_of_pauses;

  Tickspan _longest_pause;

 public:

  TimePartitions();

  ~TimePartitions();

  void clear();

  void report_gc_phase_start(const char* name, const Ticks& time, GCPhase::PhaseType type=GCPhase::PausePhaseType);

  void report_gc_phase_end(const Ticks& time, GCPhase::PhaseType type=GCPhase::PausePhaseType);

  int num_phases() const;

  GCPhase* phase_at(int index) const;

  const Tickspan sum_of_pauses() const { return _sum_of_pauses; }

  const Tickspan longest_pause() const { return _longest_pause; }

  bool has_active_phases();

 private:

  void update_statistics(GCPhase* phase);

};

class PhasesIterator {

 public:

  virtual bool has_next() = 0;

  virtual GCPhase* next() = 0;

};

class GCTimer : public ResourceObj {

  NOT_PRODUCT(friend class GCTimerTest;)

 protected:

  Ticks _gc_start;

  Ticks _gc_end;

  TimePartitions _time_partitions;

 public:

  virtual void register_gc_start(const Ticks& time = Ticks::now());

  virtual void register_gc_end(const Ticks& time = Ticks::now());

  void register_gc_phase_start(const char* name, const Ticks& time);

  void register_gc_phase_end(const Ticks& time);

  const Ticks gc_start() const { return _gc_start; }

  const Ticks gc_end() const { return _gc_end; }

  TimePartitions* time_partitions() { return &_time_partitions; }

 protected:

  void register_gc_pause_start(const char* name, const Ticks& time = Ticks::now());

  void register_gc_pause_end(const Ticks& time = Ticks::now());

};

class STWGCTimer : public GCTimer {

 public:

  virtual void register_gc_start(const Ticks& time = Ticks::now());

  virtual void register_gc_end(const Ticks& time = Ticks::now());

};

class ConcurrentGCTimer : public GCTimer {

  // ConcurrentGCTimer can't be used if there is an overlap between a pause phase and a concurrent phase.

  // _is_concurrent_phase_active is used to find above case.

  bool _is_concurrent_phase_active;

 public:

  ConcurrentGCTimer(): GCTimer(), _is_concurrent_phase_active(false) {};

  void register_gc_pause_start(const char* name, const Ticks& time = Ticks::now());

  void register_gc_pause_end(const Ticks& time = Ticks::now());

  void register_gc_concurrent_start(const char* name, const Ticks& time = Ticks::now());

  void register_gc_concurrent_end(const Ticks& time = Ticks::now());

};

class TimePartitionPhasesIterator {

  TimePartitions* _time_partitions;

  int _next;

 public:

  TimePartitionPhasesIterator(TimePartitions* time_partitions) : _time_partitions(time_partitions), _next(0) { }

  virtual bool has_next();

  virtual GCPhase* next();

};

#endif // SHARE_VM_GC_SHARED_GCTIMER_HPP